https://nova.newcastle.edu.au/vital/access/manager/Index ${session.getAttribute("locale")} 5 https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33426 Wed 31 Oct 2018 15:12:41 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33416 Wed 31 Oct 2018 15:06:32 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33418 -1) was tested against the in vitro growth of Alternaria alternata. Prior to extraction, one batch of by-product was dehydrated by freeze-drying (untreated by-product), while the other batch was treated by microwave irradiation in conjunction with freeze-drying (microwave-treated by-product). High-performance liquid chromatography (HPLC) was employed for the identification of individual phenolic compounds with potent antifungal activities. Both lemon by-product aqueous extracts inhibited the mycelial growth and suppressed the spore germination of the fungus in a concentration-dependent manner. In general, the extracts obtained from the microwave-treated lemon by-product displayed enhanced antifungal activity than those obtained from the untreated one. Scanning electron microscopy (SEM) revealed that both lemon by-product extracts affected the hyphal morphology of the fungus. The antifungal activity of the extracts was attributed to their phenolic acid and ascorbic acid contents.]]> Wed 31 Oct 2018 15:06:13 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33417 Wed 31 Oct 2018 15:05:48 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:51658 pure citral > LSTT, with 1000 μL L−1 LM EO the optimal treatment. The greater response of LM over LSTT EO was attributed to its higher concentration of citral but the greater effect over citral suggested some minor constituent(s) of LM EO also had antifungal activity. While the 120 sec dips caused severe rind injury, a 30 sec dip in 1000 µL L−1 LM EO generated only slight injury and inhibited fungal wastage in Valencia and Navel oranges, mandarins and lemons. A 10 sec dip did not cause rind injury but was less effective for mould inhibition. The findings suggest LM EO as an alternative to synthetic fungicides to inhibit wastage in citrus during storage, particularly for organic produce.]]> Wed 28 Feb 2024 14:52:11 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:51836 Wed 20 Sep 2023 16:11:03 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:29969 Phyllanthus amarus (P. amarus) is a herbal plant used in the treatment of various diseases such as hepatitis, diabetes, and cancer. Efficiency of its bioactive compounds extraction and therefore the biological activity of the extracts are significantly influenced by both solvent character and extraction method. This study is aimed at the determination of the influence of six various solvents (water, acetonitrile, ethanol, methanol, ethyl acetate, and dichloromethane) and nine different extraction methods (conventional, ultrasound-assisted, microwave-assisted, and six novel methods) on the extraction efficiency and antioxidant capacity of P. amarus. The results indicated that water extracted the maximal amount of phenolics from P. amarus and had the highest antioxidant capacity, while microwave-assisted extraction provided the highest yields of phenolics and saponins, and the highest antioxidant capacity with the lowest energy consumption when compared to the other extraction methods. These findings implied that water and microwave-assisted extraction are recommended as the most effective solvent and method for the extraction of bioactive compounds from P. amarus for potential application in the pharmaceutical and nutraceutical industries.]]> Wed 19 Jan 2022 15:19:25 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:30607 Eucalyptus species using an MTT assay. The most promising extracts were further evaluated using a CCK-8 assay. Apoptotic studies were performed using a caspase 3/7 assay in MIA PaCa-2 cells. The aqueous extract of Eucalyptus microcorys leaf and the ethanolic extract of Eucalyptus microcorys fruit inhibited the growth of glioblastoma, neuroblastoma, lung and pancreatic cancer cells by more than 80% at 100 μg/mL. The E. microcorys and Eucalyptus saligna extracts showed lower GI₅₀ values than the ethanolic Eucalyptus robusta extract in MIA PaCa-2 cells. Aqueous E. microcorys leaf and fruit extracts at 100 μg/mL exerted significantly higher cell growth inhibition in MIA PaCa-2 cells than other extracts (p < 0.05). Statistically similar IC₅₀ values (p > 0.05) were observed in aqueous E. microcorys leaf (86.05 ± 4.75 μg/mL) and fruit (64.66 ± 15.97 μg/mL) and ethanolic E. microcorys leaf (79.30 ± 29.45 μg/mL) extracts in MIA PaCa-2 cells using the CCK-8 assay. Caspase 3/7-mediated apoptosis and morphological changes of cells were also witnessed in MIA PaCa-2 cells after 24 h of treatment with the extracts. This study highlighted the significance of E. microcorys as an important source of phytochemicals with efficacy against pancreatic cancer cells. Further studies are warranted to purify and structurally identify individual compounds and elucidate their mechanisms of action for the development of more potent and specific chemotherapeutic agents for pancreatic cancer.]]> Wed 19 Jan 2022 15:15:45 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:37074 Helicteres hirsuta Lour. (H. hirsuta) has been considered as a herbal medicine for the treatment of malaria and diabetes but limited studies have been conducted on its anticancer and antibacterial properties. In this study, the in vitro antibacterial and anticancer properties of the leaf and stem extracts and their two sub-fractions (aqueous and saponin-enriched butanol fractions) prepared from H. hirsuta were elucidated. MTT and CCK-8 assays were employed to assess their in vitro anticancer properties against various cancer cell lines. The antibacterial activity was assessed using the disc diffusion method and minimum inhibitory concentration (MIC) values were determined. The results revealed that the saponin-enriched fractions from H. hirsuta leaves and stems showed the highest antibacterial activity against E. coli (MIC values of 2.50 and 5.00 mg/mL, respectively) and S. lugdunensis (MIC values of 0.35 and 0.50 mg/mL, respectively). Importantly, these saponin-enriched fractions possessed strong anticancer activity in vitro towards a range of cancer cell lines including MIA PaCa-2 (pancreas); A2780 (ovarian); H460 (lung); A431 (skin); Du145 (prostate); HT29 (colon); MCF-7 (breast); SJ-G2, U87, SMA (glioblastoma) and BE2-C (neuroblastoma) at low doses (GI₅₀ values of 0.36–11.17 µg/mL). They especially revealed potent anti-pancreatic cancer activity in vitro against MIA PaCa-2, BxPC-3 and CFPAC-1 cells with IC50 values of 1.80–6.43 µg/mL. This finding provides scientific evidence of the cytotoxic activity of the extracts prepared from H. hirsuta leaves and stems, and suggests further studies to isolate active compounds for development of new anticancer agents from these plant extracts.]]> Wed 19 Jan 2022 15:15:13 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:51031 Wed 16 Aug 2023 10:16:28 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:37967 Wed 14 Jul 2021 13:23:43 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:27325 Eucalyptus (Myrtaceae) is mainly native to Australia; however, some species are now distributed globally. Eucalyptus has been used in indigenous Australian medicines for the treatment of a range of aliments including colds, flu, fever, muscular aches, sores, internal pains, and inflammation. Eucalyptus oils containing volatile compounds have been widely used in the pharmaceutical and cosmetics industries for a multitude of purposes. In addition, Eucalyptus extracts containing nonvolatile compounds are also an important source of key bioactive compounds, and several studies have linked Eucalyptus extracts with anticancer properties. With the increasing research interest in Eucalyptus and its health properties, this review briefly outlines the botanical features of Eucalyptus, discusses its traditional use as medicine, and comprehensively reviews its phytochemical and anticancer properties and, finally, proposes trends for future studies.]]> Wed 11 Apr 2018 16:37:12 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:15165 Wed 11 Apr 2018 15:52:41 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:26324 Wed 11 Apr 2018 14:05:07 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:19404 Wed 11 Apr 2018 13:19:57 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:19242 Wed 11 Apr 2018 12:53:35 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:30206 Wed 11 Apr 2018 11:52:08 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:30609 Eucalyptus robusta leaf and to evaluate the impact of solvents, temperature, sonication time and power on ultrasound-assisted extraction of these compounds. Temperature has the greatest impact on the total phenolic content (TPC) yield followed by time and power. A yield of 163.68 ± 2.13 mg GAE/g of TPC is observed using 250 W ultrasonic power for 90 min at 60°C with water. This study validates UAE as an efficient, green, and sustainable technique for extracting phenolics from E. robusta.]]> Wed 11 Apr 2018 10:37:27 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:36554 Catharanthus roseus (L.) G. Don (C. roseus) stem. C. roseus stem was powdered and extracted with methanol using ultrasound-assisted extraction to obtain the crude extract. The crude extract was further fractioned using liquid-liquid extraction technique to obtain extracts of increasing polarity including n-butanol and residual aqueous fractions. The crude extract and its derived fractions were then subjected to phytochemical screening and assayed for antioxidant, antimicrobial and cytotoxic activities. Results showed that the n-butanol fraction contained the highest levels of saponins and phenolics (3037.54 mg ESE/g and 77.87 mg GAE/g, respectively) and possessed the strongest antioxidant capacity amongst the tested extracts. HPLC analysis revealed that this n-butanol fraction had high levels of apigenin and kaempferol, whereas the aqueous fraction contained a high level of gallic acid. The n-butanol fraction was found to effectively inhibit the activity of Escherichia coli and Staphylococccus lugdunensis. The n-butanol fraction also possessed strong cytotoxic activity in vitro against a wide range of cancer cell lines including A2780 (ovarian), H460 (lung), A431 (skin), MIA PaCa-2 (pancreas), Du145 (prostate), HT29 (colon), MCF-7 (breast), BE2-C (neuroblastoma), SJ-G2, U87 and SMA (glioblastoma) at low doses (GI50 values of 5.2−21.0 µg/mL). These results indicate that the n-butanol fraction prepared from C. roseus stem is a rich source of bioactive compounds which can be isolated for further evaluation as potential antimicrobial drugs or antitumor therapeutic agents.]]> Wed 09 Mar 2022 16:00:04 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:34580 Helicteres hirsuta Lour. (H. hirsuta L.) has been used as a traditional medicine for treatment of various ailments such as malaria and diabetes in Southeast Asian countries. This study aimed to optimize the conventional extraction conditions for obtaining the highest levels of phenolics, flavonoids, and antioxidant activities within H. hirsuta L. using response surface methodology. The Box–Behnken design was employed to evaluate the effects of extraction time, temperature, and the sample‐to‐solvent ratio on bioactive compound yield and antioxidant capacity of H. hirsuta L. The results indicated that the sample‐to‐solvent ratio had the strongest impact on bioactive compounds and antioxidant power of H. hirsuta L. and revealed the optimum extraction conditions to include temperature of 60 °C, time of 35 min at the sample‐to‐solvent ratio of 1 : 100 g/mL using 40% (v/v) methanol as the solvent. Under these conditions, the highest levels of total phenolic content and total flavonoid content were 16.87 mg GAE/g and 17.55 mg CE/g, respectively, significantly higher than the values obtained using water as the solvent. When preparing powered crude extract from H. hirsuta L., the ratio of 3 : 100 (g/mL) was suggested for the saving of 67% of solvent volume and energy required for solvent removal, as similar total phenolic content and total flavonoid content yield (86–87%) as well as antioxidant activities were obtained in comparison with the ratio of 1 : 100 (g/mL).]]> Wed 09 Feb 2022 15:55:50 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33964 Helicteres hirsuta Lour. (H. hirsuta), which has been used as a traditional medicine for malaria and diabetes treatment. Results showed that either ultrasonic temperature or sample-to-solvent ratio had a greater influence on extraction efficiency of total phenolics, flavonoids and antioxidant capacity than that of methanol concentration. Optimal extraction conditions were determined to be ultrasonic temperature of 60 °C, ultrasonic time of 25 min, ultrasonic power of 150W, sample-to-solvent ratio of 3:100 g/mL, and a solvent composition of 40% (v/v) aqueous methanol. Under these conditions, 15.97 mg GAE/g of phenolics, 16.42 mg CE/g of flavonoids, and 13.34 g/100 g of extractable solids were obtained. The highest values for DPPH, ABTS and FRAP assays were also obtained under these conditions, with the exception of CUPRAC (88% maximum value). These optimal extraction conditions can be applied to prepare powdered crude extract for further isolation and purification of individual bioactive compounds for potential use in the pharmaceutical industry.]]> Wed 09 Feb 2022 15:54:39 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:24691 Phyllanthus amarus is known as a healing herb which has traditionally been used in the treatment of various diseases such as hepatitis, diabetes and cancer. The extraction parameters have great effects on the extraction efficiency of bioactive compounds and pharmacological activity of the extracts. This study sought to optimise the microwave-assisted extraction parameters for phenolic compounds-enriched extracts and antioxidant capacity from P. amarus using response surface methodology (RSM). The results showed that the optimal microwave-assisted extraction parameters were an extraction time of 30 min, an irradiation time of 14 s min⁻¹ and a ratio of solvent to sample of 150 mL g⁻¹. The total phenolic content, phenolic extraction efficiency, saponin content, 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging capacity, 2,2-diphenyl-1-picryl-hydrazil (DPPH) radical scavenging capacity and ferric reducing antioxidant power of the P. amarus achieved under these optimal parameters were 87.3 mg of gallic acid equivalents (GAE) per gram of dried sample, 69.7 %, 134.9 mg of escin equivalents (EE) per gram of dried sample, 997.8, 604.7 and 437.3 all in mg of trolox equivalents (TE) per gram of dried sample, respectively, which were not significantly different from the predicted values (86.9 mg of GAE per gram of dried sample, 67.3 %, 123.5 mg of EE per gram of dried sample, 1013.3 mg of TE per gram of dried sample, 530.6 mg of TE per gram of dried sample and 423.5 mg of TE per gram of dried sample, respectively). Accordingly, the optimal microwave-assisted extraction parameters of 30 min, 14 s min⁻¹ and 150 mL g⁻¹ are recommended for the extraction of enriched phenolics from P. amarus for potential application in the nutraceutical and pharmaceutical industries.]]> Wed 09 Feb 2022 15:54:22 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:34077 Helicteres hirsuta Lour. The results revealed that all the three powdered extracts from the leaves and the stems possessed high levels of phenolics (177.07–241.03 mg GAE g⁻¹), flavonoids (158.03–280.06 mg CE g⁻¹) and saponins (165.77–1035.33 mg ESE g⁻¹) and exhibited strong antioxidant capacity. HPLC analysis identified nine major compounds in the leaf powder crude extract; however, the leaf aqueous fraction had three extra compounds; whereas, the saponin-enriched butanol leaf fraction had seven extra compounds. For the stems, twelve main compounds were evident in either the powdered crude extract or the aqueous fraction, and five new compounds were revealed in the saponin-enriched butanol fraction. The findings revealed that the powdered aqueous fractions and saponin-enriched butanol fractions are potential sources of biologically active compounds for further investigation and industrial utilisation.]]> Wed 06 Feb 2019 14:24:17 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:43987 Wed 05 Oct 2022 14:36:22 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:43936 Wed 05 Oct 2022 12:44:37 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33432 Solanum lycopersicum L. cv Neang Pich) were exposed to 13.6 kJ m^-2 UV-C or 0.5 µL L^-1 1-MCP or combination of 13.6 kJ m^-2 UV-C and 0.5 µL L^-1 1-MCP, with appropriate untreated controls. After treatment, tomatoes were stored in air containing 0.1 µL L^-1 ethylene at 20°C and 100% RH. The untreated fruit ripened significantly faster than those of all other treatments. UV-C treatment alone was able to delay fruit ripening by up to 5 days longer compared to untreated fruits whilst the additional of 1-MCP further delayed fruit ripening. UV-C and 1-MCP treatments alone or in combination had significantly slower ethylene production rates throughout the storage period. The fruit treated with the combination of 1-MCP and UV-C was significantly firmer and had higher total phenolic content compared to that of the other treatments. However, there was no difference between treatments in soluble solids content/titratable acids ratio, chlorophyll content, lycopene content and total antioxidant activity. These results show that UV-C and 1-MCP treatment delay ripening and improve the quality of tomatoes in the presence of low-level ethylene during storage. This new treatment could be used to extend the shelf-life of mature green tomatoes through the supply chain without the use of refrigeration.]]> Wed 04 Sep 2019 09:56:41 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:50021 Tue 27 Jun 2023 15:37:42 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:32046 p‐coumaric acid content. The highest gallic acid content was recorded in the pomace dried by hot air at 110°C. The results of this study indicate that drying technique should be carefully selected according to the bioactive compounds aimed to be extracted.]]> Tue 24 Apr 2018 15:09:46 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:40821 Tue 19 Jul 2022 09:47:29 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:26014 Tue 17 Mar 2020 11:33:29 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:42901 Helicteres hirsuta Lour. (H. hirsuta L.) have been used as traditional medicines, however limited studies have been conducted on the preparation of dried material or the extraction of bioactive compounds. This study aimed to determine the effect of various solvents and drying methods on the bioactive compound yield and antioxidant capacity of the H. hirsuta L. stem. The results showed that water was the best solvent for obtaining the highest levels of phenolics and flavonoids, whereas methanol was the solvent of choice for saponin extraction. Among assessed drying methods, hot-air drying at 80C revealed as the best method to maintain the bioactive components (phenolics of 8.99 mg GAE/g, flavonoids of 9.60 mg CE/g and saponins of 15.18 mg ESE/g), and DPPH, ABTS, and FRAP antioxidant activities. Thus hot-air drying at 80C is recommended for preparation of dried H. hirsuta L. stem for further processing steps.]]> Tue 06 Sep 2022 15:35:23 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:43875 Tue 04 Oct 2022 12:28:48 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33421 Cucurbita pepo var. cylindrica) were stored at low pressure (4 kPa) at 10°C at 100% relative humidity (RH) for 11 days. Fruit quality was examined upon removal and after being transferred to normal atmosphere (101 kPa) at 20°C for three days. Zucchinis stored at low pressure exhibited a 50% reduction in stem-end browning compared with fruit stored at atmospheric pressure (101 kPa) at 10°C. The benefit of low pressure treatment was maintained after the additional three days storage at normal atmospheric pressure at 20°C. Indeed, low pressure treated fruit transferred to regular atmosphere 20°C for three days possessed a significantly lower incidence of postharvest rot compared to fruit stored at regular atmospheric pressure at 10°C. Zucchinis stored at low pressure showed higher levels of acceptability (28% and 36 % respectively) compared to fruit stored at regular atmospheres at 10°C for both assessment times.]]> Tue 03 Sep 2019 18:18:41 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:34804 -1 of ethylene at either 5, 10 or 20 °C, whilst in a parallel experiment, Navel oranges were exposed to ≤0.001, 0.1 and 1 µL L^-1 ethylene at either 1 or 10 °C. Changes in external and internal postharvest quality parameters were assessed for up to 8 weeks for 'Afourer' mandarins and 10 weeks for Navel oranges. At all storage temperatures, high levels of ethylene were found to increase the level of calyx senescence, weight loss, loss of fruit firmness and respiration rates. Also, there were significant effects of ethylene and storage temperatures on total soluble solids (TSS) content, titratable acidity (TA), and ethanol accumulation in both citrus species. Continuous exposure to high ethylene also significantly reduced vitamin C and ferric reducing antioxidant power (FRAP) in 'Afourer' mandarins after 8 weeks of storage. Overall, ethylene treatments had a significant effect on both the external and internal qualities of the fruit during storage. The relationship between ethylene concentrations and storage temperatures demonstrate that lowering atmospheric ethylene levels at reduced storage temperatures maintain fruit quality during long term storage.]]> Tue 03 Sep 2019 17:58:57 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:34803 -2). After treatment, mangoes were stored for 12 d in air (<0.005 µL L^-1 ethylene) or 0.1 µL L^-1 ethylene at 20 °C and 100% relative humidity (RH). Weight loss, peel colour, firmness, ethylene production, respiration rate, total soluble solids (TSS), titratable acidity (TA), total chlorophyll content, total phenolic content (TPC) and total antioxidant activity were assessed at 3-d intervals. The results showed that UV-C treatment delayed skin degreening, reduced endogenous ethylene production, suppressed respiration rate and lowered chlorophyll content compared to untreated control fruit. Fruit treated with UV-C had significantly higher TPC and total antioxidant activity at the end of the storage period than untreated fruits for both storage atmospheres. In addition, UV-C treated fruits remained significantly firmer than untreated fruits. UV-C treatment significantly affected TSS and TA levels in different ways. Storage of fruits in 0.1 µL L^-1 ethylene significantly affected fruit firmness, respiration rate and ethylene production, while other fruit quality parameters were similar to fruit stored in air. These results indicated that UV-C irradiation could be used as an effective and rapid method to extend the postharvest life of mature green mangoes without adversely affecting certain quality attributes in the presence of low-level ethylene during storage.]]> Tue 03 Sep 2019 17:58:50 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:31209 Cupaniopsis anacardioides) is an Australian native plant that fruits over the summer months. There are very few studies that have characterised its fruit; consequently, this study aimed to delineate the physical, phytochemical and antioxidant properties of the tuckeroo fruit. The tuckeroo skin embodied the largest weight proportion with over 77% of the total fruit weight and it had the highest levels of total phenolic compounds (TPC; 151.36 mg GAE/g), total flavonoids compounds (TFC; 95.94 mg CAE/g), and proanthocyanidins (Proanth; 164.86 mg CAE/g) content, as well as the strongest antioxidant power. The seed and flesh accounted for 23% of the total fruit weight and they possessed significantly lower levels of TPC, TFC and Proanth. This study has demonstrated that the tuckeroo fruit skin is a rich source of phenolic compounds, which can be further isolated and identified for further utilisation in the food and pharmaceutical industries.]]> Tue 01 May 2018 09:18:35 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:41193 Thu 28 Jul 2022 11:12:21 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:37278 Salacia chinensis L. root; investigate the impact of solvents on yield; optimise the ultrasound-assisted extraction (UAE) technique; and compare mangiferin yield with continuously shaking extraction (CSE) and decoction techniques. The results showed that mangiferin, with a purity of over 88%, could be achieved by HPLC using a mixture of solvent A (water: acetonitrile: orthophosphoric acid, 96.8:3:0.2 (v/v/v)) and solvent B (acetonitrile). Solvent type significantly affected the extraction yield of mangiferin, and a mixture of acetone and water gave the highest extraction yield, as compared to other solvents or mixtures. UAE conditions, such as ultrasonic power, temperature, time and concentration of acetone significantly affected the extraction of mangiferin. Optimal UAE conditions were at an ultrasonic power of 250 W, temperature of 50 °C, acetone concentration of 40% and extraction time of 60 min. These optimal conditions could extract approximately 92 mg, whereas CSE and decoction only extracted 89.20 mg and 58.71 mg of mangiferin, respectively, from 1 g of S. chinensis root. Therefore, these UAE conditions are recommended for the extraction of mangiferin from S. chinensis root for further utilisation.]]> Thu 27 Jan 2022 15:56:51 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:42563 Thu 25 Aug 2022 11:12:18 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:34760 BisP1: 1,5-diphenyl-3,7-bis(2-hydroxyethyl)-3,7-diazabicyclo[3.3.1]nonan-9-one; BisP2: 3,7-bis-(2-(S)-amino-4-methylsulfanylbutyryl)-1,5-diphenyl-3,7-diazabicyclo[3.3.1]nonan-9-one dihydrochloride; BisP3: [2-{7-[2-(S)-tert-butoxycarbonylamino-3-(1H-indol-3-yl)-propionyl]-9-oxo-1,5-diphenyl-3,7-diazabicyclo[3.3.1]non-3-yl}-1-(S)-(1H-indol-3-ylmethyl)-2-oxoethyl]-carbamic acid tertbutyl ester; BisP4: 3,7-bis-[2-(S)-amino-3-(1H-indol-3-yl)-propionyl]-1,5-diphenyl-3,7-diazabicyclo[3.3.1]nonan-9-one dihydrochloride) was assessed against PC cell lines (MiaPaca-2, CFPAC-1 and BxPC-3). Cell viability was assessed using a Cell Counting Kit-8 (CCK-8) colorimetric assay, while apoptotic cell death was confirmed using fluorescence microscopy and flow cytometry. Initial viability screening revealed significant cytotoxic activity from BisP4 treatment (1 µM⁻100 µM) on all three cell lines, with IC50 values for MiaPaca-2, BxPC-3, and CFPAC-1 16.9 µM, 23.7 µM, and 36.3 µM, respectively. Cytotoxic treatment time-response (4 h, 24 h, and 48 h) revealed a 24 h treatment time was sufficient to produce a cytotoxic effect on all cell lines. Light microscopy evaluation (DAPI staining) of BisP4 treated MiaPaca-2 PC cells revealed dose-dependent characteristic apoptotic morphological changes. In addition, flow cytometry confirmed BisP4 induced apoptotic cell death induction of activated caspase-3/-7. The bispidinone derivative BisP4 induced an apoptosis-mediated cytotoxic effect on MiaPaca-2 cell lines and significant cytotoxicity on CFPAC-1 and BxPC-3 cell lines. Further investigations into the precise cellular mechanisms of action of this class of compounds are necessary for potential development into pre-clinical trials.]]> Thu 17 Mar 2022 14:34:42 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:36553 Catharanthus roseus (L.) G. Don (C. roseus) is a well-known medicinal plant for its source of alkaloids solely found in the leaves. Other parts including the root are usually discarded after the alkaloid extraction. This study sought to investigate phytochemical profiles, antioxidant, antimicrobial and cytotoxic properties of the C. roseus root extract (RE) and its two sub-fractions including saponin-enriched (SE) and aqueous (AQ) fractions. The results showed that the RE was a rich source of saponins (1744.44 mg ESE/g) and phenolics (51.27 mg GAE/g), which comprised of gallic acid (25.74 mg/g), apigenin (1.45 mg/g) and kaempferol (1.58 mg/g). The SE fraction was enriched with 31% of saponins and 63% of phenolics higher than those of the RE; whereas the concentrations of saponins and phenolics of the AQ fraction were lower than those of the RE by 40% and 74%, respectively. The content of gallic acid in the SE fraction was 1.4-fold and 1.5-fold higher than those of the RE or AQ fraction, respectively. The SE fraction demonstrated potent antioxidant capacity, which was significantly higher than the RE or AQ fraction, and also exhibited strong anti-proliferative activity against 11 cancer cell lines including A2780 (ovarian), H460 (lung), A431 (skin), MIA PaCa-2 (pancreas), Du145 (prostate), HT29 (colon), MCF-7 (breast), BE2-C (neuroblastoma), SJ-G2, U87 and SMA (glioblastoma) with low GI₅₀ values (≤ 2.00 µg/mL). The SE fraction was also shown to effectively inhibit the growth of both bacteria (Escherichia coli, Enterobacter aerogenes and Staphylococccus lugdunensis) and fungi (Candida albicans and Aspergillus niger). These findings warrant further investigation to isolate major compounds from the SE fraction and further test their antioxidant, anticancer and antimicrobial activities.]]> Thu 17 Feb 2022 09:27:14 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:23950 Paramignya trimera (Oliv.) Guillaum) has been used as an herbal medicine for the treatment of cancer or cancer-like diseases in recent years, particularly in Vietnam. Drying is an important step for preparation of dried materials for storage and further investigation; however, the effects of drying must be taken into account when processing samples, because this can have profound effects on the stability of phytochemical compounds and the biological activity of the dried P. trimera root. As such, this study assessed the effects of four different drying methods (conventional, hot air, vacuum, and microwave) on phytochemical retention and antioxidant capacity of P. trimera root, to identify an optimal drying method for P. trimera root. The results showed that the drying methods significantly affected phytochemical levels and antioxidant capacity of P. trimera root and that among the four drying methods tested, microwave drying (400 W) had the highest levels of phytochemical compounds, with total phenolic, total flavonoid, proanthocyanidin, and saponin contents of 11.27 mg GAE, 19.88 mg RE, 3.98 mg CE, and 267.15 mg EE/gram of dried sample, respectively. Dried sample prepared using this method had antioxidant capacity comparable to that of other drying methods. In addition, this method had the shortest drying time (0.28 h) and consumed the least energy (0.28 kWh). Therefore, microwave drying should be considered for drying P. trimera root for further investigation and utilization.]]> Thu 17 Feb 2022 09:26:20 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:50836 Thu 17 Aug 2023 11:57:21 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33409 Eucalyptus microcorys extract against pancreatic cancer cell lines. In this study, bioassay-guided fractionation of the aqueous crude E. microcorys extract using RP-HPLC and subsequent assessment of the resultant fractions (F1-F5) for their antioxidant activity and cytotoxicity against pancreatic cancer cell lines were performed. The molecular mechanisms associated with the cytotoxicity was characterised by studying the effects of the most potent fraction-1 (F1) on apoptosis and cell cycle profiles as well as its phytochemical constituents by LC-ESI/MS/MS. F1 displayed significantly greater antioxidant activity in three different assays (p < 0.05). Moreover, F1 exhibited significantly greater antiproliferative activity (IC₅₀ = 93.11 ± 3.43 µg/mL) against MIA PaCa-2 cells compared to the other four fractions (p < 0.05). F1 induced apoptosis by regulating key apoptotic proteins- Bcl-2, Bak, Bax, cleaved PARP, procaspase-3 and cleaved caspase-3 in MIA PaCa-2 cells, suggesting the involvement of intrinsic mitochondrial apoptotic pathway and arrested cells at G2/M phase. A combination of gemcitabine and F1 exerted a greater effect on apoptosis and cell cycle arrest than F1 or gemcitabine alone (p < 0.05). LC-ESI/MS/MS revealed the tentative identities of phytochemicals present in F1 and their similarities with the phenolic compounds previously reported in Eucalyptus with antipancreatic cancer activity. Our study shows that the polyphenol and antioxidant-rich fraction of E. microcorys extract is a promising candidate for developing mono or combination therapies against pancreatic cancer.]]> Thu 09 Dec 2021 11:03:58 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:30611 Corymbia and Angophora. Four Angophora and Corymbia species were evaluated for their phytochemical profile and efficacy against both primary and secondary pancreatic cancer cell lines. The aqueous leaf extract of Angophora hispida exhibited statistically higher total phenolic content (107.85 ± 1.46 mg of gallic acid equiv. per g) and total flavonoid content (57.96 ± 1.93 mg rutin equiv. per g) and antioxidant capacity compared to the other tested eucalypts (P < 0.05). Both A. hispida and A. floribunda aqueous extracts showed statistically similar saponin contents. Angophora floribunda extract exerted significantly greater cell growth inhibition of 77.91 ± 4.93% followed by A. hispida with 62.04 ± 7.47% (P < 0.05) at 100 μg/ml in MIA PaCa-2 cells with IC₅₀ values of 75.58 and 87.28 μg/ml, respectively. More studies are required to isolate and identify the bioactive compounds from these two Angophora species and to determine their mode of action against pancreatic malignancies.]]> Thu 09 Dec 2021 11:03:07 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:29794 Thu 04 Nov 2021 10:39:37 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33408 Thu 04 Nov 2021 10:39:25 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:55030 Backhousia citriodora) essential oil (EO) was investigated to combat Penicillium digitatum by in vitro agar diffusion and vapour assay and in artificially infected oranges. The main constituent of LM EO was revealed as citral when analysed in gas chromatography–mass spectrometry. Pure citral was also included in the experiment for comparison. The in vitro fungal growth was significantly inhibited by LM EO at 1, 2, 3, 4 and 5 μL per disc while complete growth inhibition by both the pure citral and LM EO occurred at 4 and 5 μL per disc. Inoculated fruits treated by dipping in 1000 μL L⁻¹ LM EO solutions for 5, 10, 15, 30 and 120 s showed significantly lower fungal wounds compared to control. While longer dipping times led to some rind injuries, fruits with a 5 and 10 s dip were found free from any injury. The evaluation after dipping and storage confirmed that the fruits maintained the sensory attributes and were not compromised by the incorporation of the essential oil. The results of this study indicate that LM EO can be a promising alternative to synthetic fungicides for preserving the quality of citrus fruits during storage.]]> Thu 04 Apr 2024 10:28:37 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:31497 Sat 24 Mar 2018 08:44:08 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:7046 Sat 24 Mar 2018 08:37:54 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:8039 Sat 24 Mar 2018 08:35:04 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:1259 Sat 24 Mar 2018 08:32:47 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:1291 Sat 24 Mar 2018 08:32:46 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:1075 Sat 24 Mar 2018 08:32:09 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:1613 Sat 24 Mar 2018 08:30:33 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:1233 Sat 24 Mar 2018 08:28:34 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:2355 Sat 24 Mar 2018 08:27:55 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:1773 1000 μM. Analogues possessing good PP1 and/or PP2A inhibition also returned moderate to good anti-cancer activity. Analogues with substituents directly attached to the intact bicyclo[2.2.1]heptane skeleton were poor to moderate anti-cancer agents. This correlates well with their lack of PP1 or PP2A activity. Analogues capable of undergoing a facile ring opening of the anhydride or with a single carboxylate were good PP1 and PP2A inhibitors, largely correlating to the observed anti-cancer activity in all cases, except 11. Analogue 11, whist neither a PP1 nor a PP2A inhibitor shows anti-cancer activity comparable to 1 and 2. We believe that intracellular esterases generate the corresponding dicarboxylate, which is a potent PP1 and PP2A inhibitor, and that it is this species which is responsible for the observed anti-cancer activity.]]> Sat 24 Mar 2018 08:27:36 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:10944 Sat 24 Mar 2018 08:10:41 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:20454 Sat 24 Mar 2018 08:06:57 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:21238 N,N-dimethyl-4'-vinylbiphenyl-3-amine (M3), (4'-vinylbiphenyl-4-yl)methanol (M4), 4'-vinylbiphenyl-4-carboxylic acid (M5) and 4-hydroxy-5-methyl-4'-vinylbiphenyl-3-carboxylic acid (M6), were examined for their ability to imprint theophylline (1). Using a molecular modelling-NMR titration approach, M2 and M6 were predicted to give rise to the most specific molecularly imprinted polymers (MIPs). Rebinding analysis suggests that no imprinting effect resulted from the polymerisation of monomers M1 , M5 and M6, but modest to good levels of imprinting were evident from monomers M2, M3 and M4 with IF values ranging from 1.1 (MIP_M3, 20 mg) to 45 (MIP_M2, 10 mg). The selective recognition of 1 varied as a function of polymer mass used. At low polymer loadings MIP_M2 gave the very high IF of 45, reducing to IF = 4.1-2.3 at 20-40 mg polymer loading. With monomer M2, microwave synthesised MIP (MW-MIP_M2) was examined. The MW-MIP_M2 displayed lower specific rebinding than its conventionally produced counterpart (MIP_M2) with IF values ranging from 1.6-2.3 (cf., MIP_M2 IF 2.3-45), but significantly higher levels of rebinding with 25-52% of 1 rebound from a 0.080 mM CH₃CN solution of 1 (cf., MIP_M2 5-25%). MW-MIP_M2 displayed a lower BET surface area than MIP_M2 (185 m² g^-1vs. 240 m² g^-1), and lower surface (zeta) potential (-13.1 ± 8.22 mV vs. -31.4 ± 4.84 mV). Freundlich isotherm analysis revealed that MW-MIP_M2 possessed higher affinity binding sites for 1 than MIP_M2 with K_d values of 1.38 and 2.31 respectively. In addition, MW-MIP_M2 also exhibits a higher number of binding sites (N_⏉) compared to MW-NIP_M2 (0.72 and 0.41 mg g^-1, respectively). In specificity studies using caffeine (2), MIP_M2 displayed a two-fold preference for rebinding of 1 and MW-MIP_M2 a five-fold preference for 1 over 2 . The quantity of 2 bound in both cases was consistent with non-specific binding events. In competitive rebinding experiments, increased discrimination in favour of 1 over 2 was observed.]]> Sat 24 Mar 2018 07:53:03 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:21239 4], [BMIM][PF₆], [HMIM][PF₆] and [OMIM][PF₆] and CHCl₃ were examined. The observed IF (imprinting factor) values for MIP_BF4, MIP_PF6 and MIP_CHCl3 were 1.0, 1.98 and 4.64, respectively. The longer chain HMIM and OMIM systems returned lower IF values of 1.1 and 2.3, respectively. MIP_PF6 also showed a ~25% binding capacity reduction vs. MIP_CHCl3 (5 μmol g^-1 vs. 7 μmol g^-1 respectively). MIP_CHCl3 and MIP_PF6 differed in terms of BET surface area (306 m² g^-1vs. 185 m² g^-1), pore size (1.10 and 2.19 nm vs. 0.97 and 7.06 nm), the relative number of pores (Type A: 10.4 vs. 7.5%; Type B: 8.5 vs. 3.0%), and surface zeta potential (-37.9 mV vs. -20.3 mV). The MIP specificity for 1 was examined by selective rebinding studies with caffeine (2) and ephedrine (3). MIP_PF6 rebound higher quantities of 2 than MIP_CHCl3 , but this was largely due to non-specific binding. Both MIP_CHCl3 and MIP_PF6 showed a higher affinity for 3 than for 2. Reduction in the Room Temperature Ionic Liquid (RTIL) porogen volume had little impact on the polymer morphology, but did result in a modest decrease in IF from 2.6 to 2.3 and in the binding capacity (30% to 19%). MIP_CHCl3 retained the highest template specificity on rebinding from CHCl₃ (IF = 4.6) dropping to IF = 0.6 in MeOH/[BMIM][PF₆]. The MIP_CHCl3 binding capacity remained constant using CHCl₃, CH₂Cl₂ and MeOH (46-52%), dropped to 6% on addition of [BMIM][PF₆] and increased to 83% in H₂O (but at the expense of specificity with IF_H2O = 1.4). MIP_PF6 rebinding from MeOH saw an increase in specific rebinding to IF = 4.9 and also an increase in binding capacity to 48% when rebinding 1 from MeOH and to 42% and 45% with H₂O and CH₂Cl₂, respectively, although in the latter case the increased capacity was at the cost of specificity with IF_CH2Cl2 = 1.2. Overall the MIP_PF6 capacity and specificity were enhanced on addition of MeOH.]]> Sat 24 Mar 2018 07:53:03 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:20130 Sat 24 Mar 2018 07:51:33 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:28484 Davidsonia pruriens F. Muell) and to assess the physicochemical and antioxidant properties of the phenolic-enriched extract. The results showed that temperature, time and ratio significantly affected the extraction of TPC. Optimization of extraction conditions was performed using response surface methodology (RSM) utilising a Box–Behnken design. Optimal extraction conditions were determined to be temperature: 90 °C, extraction time: 30 min and solvent to mass ratio: 20:1 mL g⁻¹. The extracted solid obtained under these conditions had low-moisture content, high water solubility and contained 45 mg GAE g−1 of TPC, 22 mg RUE g⁻¹ of flavonoids, 3.2 mg CAE g⁻¹ of proanthocyanidins, 2 mg CGE g⁻¹ of anthocyanidins and 56 mg ACE g⁻¹ vitamin C. The extract possessed potent antioxidant capacity, but was comparatively lower than those of vitamin E and BHT. Thus, Davidson's plum should be further investigated for its potential health promoting benefits and utilisation in the nutraceutical and food industries.]]> Sat 24 Mar 2018 07:39:36 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:27329 Eucalyptus robusta (Sm.) (ER) is a widely distributed tree native to the east coast of Australia, which has also been established in numerous other countries. ER leaves contain high levels of essential oils and are rich in total phenolic compounds (TPC), which have been linked with health benefits; however, there is limited information on the bioactivity of ER leaf extracts. This study aimed to optimise water extraction conditions for TPC, prepare a spray-dried powdered extract and test its physicochemical, antioxidant and anti-proliferative properties. The results showed that optimal water extraction conditions for TPC were 85°C, 15 min and a water-to-leaf ratio of 20:1 mL/g. Under these conditions, spray-dried powdered extract was prepared with a recovery yield of 85%. The extract was water-soluble and had a TPC level of 407 mg GAE/g. It also possessed potent antioxidant capacity, comparable to pure ascorbic acid, but higher than pure α-tocopherol. In addition, the powdered extract demonstrated significant activity against a panel of cancer cell lines, which included cancers of the pancreas, breast, lung, brain, skin, colon and ovary. Of note, the ER extract exerted a more significant toxic effect on pancreatic cancer (PC) cells compared to gemcitabine, the first line chemotherapeutic agent for PC. We suggest that future studies should purify individual bioactive compounds from ER for further investigation of its potential health promoting and anti-cancer activity.]]> Sat 24 Mar 2018 07:38:37 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:27327 Vitex agnus-castus (Vitex AC) leaves have been used for medicinal purposes for many years. Drying is important to prepare starting materials for further processing, as it is associated with production cost and quality of the materials. Herein, the effects of five different drying conditions on the physical, chemical and antioxidant properties of Vitex AC were evaluated. The results showed that 30% of dried leaves with moisture content of less than 7% could be produced from fresh leaves. Vitex AC leaves dried by freeze and vacuum drying at 65C had higher levels of bioactive compounds as well as higher antioxidant capacity in comparison with other drying conditions, revealing that these drying conditions are more suitable for drying Vitex AC leaves. However, freeze drying is costly and time-consuming; thus, vacuum drying at 65C is suggested for drying the Vitex AC leaves as the starting materials for further processing steps. Practical Applications: As drying is an important process to prepare starting materials for further processing steps, it is important to compare different drying methods to identify the most suitable method with low cost and less effect on material quality. The results showed that inappropriate drying conditions resulted in big loss of bioactive compounds and antioxidant capacity. Vacuum drying at 65C was found to be the most suitable method, which can be easily applied for drying Vitex agnus-castus leaves in the industrial scale.]]> Sat 24 Mar 2018 07:38:36 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:27402 Phyllanthus amarus (P. amarus) has been used as a herbal medicine, particularly for liver support, in many countries and its extracts have been shown to possess potent antioxidant and anticancer properties in vitro. The preparation of dried sample is crucial for further extraction and isolation of phytochemicals. In this study, the effects of six different drying methods (hot air, low-temperature air, infrared, microwave, sun, and vacuum drying) on the phytochemical yield and antioxidant capacity were determined to identify the optimal drying method for P. amarus. The results showed that different drying methods, as well as different drying conditions within each method, significantly affected phytochemical yield and antioxidant capacity of P. amarus extracts. Infrared drying at 30°C was the best method for both retention of bioactive compound yield and antioxidant capacity of P. amarus extract, with 12 compounds were identified. In contrast, low-temperature-air drying at 25°C not only required the longest drying time but also significantly reduced the levels of bioactive compounds and antioxidant capacity of P. amarus. Therefore, infrared drying at 30°C is suggested for drying P. amarus for subsequent assessment of bioactivity.]]> Sat 24 Mar 2018 07:34:08 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:29718 Sat 24 Mar 2018 07:33:25 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:29664 −1. Under these conditions, the aqueous extracts had the same content of TPC and TF as well as antioxidant capacity in comparison with those of methanol extracts obtained by sonication. Therefore, these conditions could be applied for further extraction and isolation of phenolic compounds from lemon pomace]]> Sat 24 Mar 2018 07:32:23 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:29890 Sat 24 Mar 2018 07:29:53 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:25688 Sat 24 Mar 2018 07:28:23 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:28009 Eucalyptus robusta (E. robusta) has a significant value in traditional medicine and recently has been shown to possess many pharmacological properties in vitro. This study was designed to utilise microwave-assisted extraction (MAE) to yield optimal total phenolic content (TPC), total flavonoid content (TFC), proanthocyanidin levels and antioxidant capacity from E. robusta using water as the solvent, facilitated by the use of response surface methodology (RSM). A three-level-three-factor Box–Behnken design was implemented to elucidate the effect of irradiation time, power and sample-to-solvent ratio on the yields of these phytochemicals. The results highlighted the accuracy and reliability of RSM as a tool for predicting the yields of TPC, TFC, proanthocyanidins and total antioxidants using MAE. Sample-to-solvent ratio had the greatest impact on the TPC yield followed by power and irradiation time. The optimal MAE conditions for TPC and TFC were 3 min, 600 W power and 2 g/100 mL sample-to-solvent ratio. The experimental yield of TPC was 58.40 ± 1.03 mg GAE/g, and 19.15 ± 1.06 mg RE/g of TFC was obtained under these optimal conditions. These conditions, optimised for maximum TPC yield also liberated 62%, 64.6%, 66.3% and 67% of the maximum proanthocyanidins, ABTS, DPPH and CUPRAC values, respectively. This study revealed that MAE is a reliable and efficient method for extracting high yields of phytochemicals from E. robusta, with significant potential to be up-scaled for industrial, nutraceutical or pharmaceutical applications.]]> Sat 24 Mar 2018 07:27:18 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:3328 Sat 24 Mar 2018 07:23:20 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:3329 Sat 24 Mar 2018 07:23:20 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:3324 40- and >30-fold selectivity) over PP2A. Both compounds exhibited moderate PP1 activity, 3 IC₅₀ 50 μM and 6 IC₅₀ 12.5 μM. Interestingly, the corresponding mono-ester derivatives of 3 showed no such selectivity.]]> Sat 24 Mar 2018 07:23:20 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:23414 Euphorbia tirucalli (E. tirucalli) has been linked with various health benefits. This study aimed to optimize ultrasonic extraction conditions for euphol from E. tirucalli leaf. Different solvents were tested to determine the most effective solvent for extraction of euphol. Then, response surface methodology (RSM) was employed to optimize ultrasound-assisted extraction conditions including temperature, time and power for maximal extraction of euphol. Our results showed that ethyl acetate:ethanol (4:1, v/v) was the most effective solvent for the extraction of euphol. Ultrasonic temperature and time had a positive impact, whereas, ultrasonic power had a negative effect on the extraction efficiency of euphol. The optimum ultrasonic extraction conditions for euphol were identified as: solvent-to-fresh sample ratio of 100:32 mL/g; ultrasonic temperature of 60 °C; ultrasonic time of 75 min and ultrasonic power of 60% (150 W). Under these optimum conditions, approximately 4.06 mg of euphol could be obtained from one gram of fresh E. tirucalli leaf. This extract also contained phenolic compounds (2.5 mg GAE/g FW) and possessed potent antioxidant capacity. These optimal conditions are applicable for a larger scale to extract and isolate euphol for potential utilization in the pharmaceutical industry. Keywords]]> Sat 24 Mar 2018 07:13:54 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:23489 Sat 24 Mar 2018 07:13:05 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:23861 Sat 24 Mar 2018 07:12:11 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:31216 Solanum lycopersicum cv. Neang Pich) were stored at low pressure (4 kPa) at 10°C for 11 days with 100% RH. Fruit quality was examined upon removal and after being transferred to normal atmosphere (101 kPa) at 20°C for 3 days. Weight loss was significantly lower in fruits which were stored at low pressure (4 kPa) than in fruits that were stored at regular atmosphere (101 kPa) at 10°C. Fruits that were stored at low pressure (4 kPa) reduced calyx browning by 12.5%, and calyx rots by 16%, compared to fruits that were stored at regular atmosphere (101 kPa) at 10°C. Fruit firmness was not significantly different between fruits stored at low pressures (4 kPa) and the normal atmosphere (101 kPa), with an average firmness of 14 N after fruits were stored at 10°C for 11 days. There was no difference in the SSC/TA ratio. The results suggest that a low pressure of 4 kPa at 10°C has potential as an alternative, non-chemical postharvest treatment to improve tomato quality during storage.]]> Mon 23 Sep 2019 12:38:29 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:40415 Cupaniopsis anacardioides) is an Australian native tree, possessing high level bioactivity and antioxidant activity. To prevent deterioration of active constituents, appropriate drying practices must be determined. This study comparatively evaluates the impact of a range of drying methods including freeze-, microwave-, vacuum-, hot air- and sun-drying on the physical, phytochemical and antioxidant characteristics of Tuckeroo fruit. Experimental results showed that the five drying methods had significant impact on the physicochemical properties and antioxidant activity of the fruits. Of the drying methods assessed, freeze drying best preserved Tuckeroo activity, recording higher total phenolic content (TPC) (81.88 mg gallic acid equivalent (GAE)/g), total flavonoids (TFC) (107.71 mg catechin equivalent (CAE)/g), proanthocyanidins (TPro) (83.86 mg CAE/g) and exhibited the strongest antioxidant capacity. However, vacuum drying at 65 kPa, 100 ℃ for 5 h is recommended for drying Tuckeroo fruits for further processing in a large scale as it also retained high levels of TPC, TFC and TPro (58 mg GAE/g, 91 mg CAE/g and 74 mg CAE/g, respectively).]]> Mon 11 Jul 2022 14:44:41 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:55060 Mon 08 Apr 2024 12:31:58 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33429 Capsicum annum L.) were stored under low pressure (4 kPa) at 10°C for 5 and 11 days with 100% RH. The results showed that the incidence of stem decay under low-pressure storage for 5 and 11 days and storage at ambient atmosphere at 20°C for 3 days was lower compared to fruits that were stored at regular atmosphere at 10°C. Fruit that had been stored at low pressure at 10°C had no symptoms of flesh rots for up to 11 days, whilst fruit which had been stored at regular atmosphere at 10°C had 6% flesh rots after 11 days storage at 10°C.There was no difference in flesh firmness and colour retention between fruits stored at low pressure and regular pressure at 10°C. Capsicums stored at low pressure had higher overall acceptability compared to fruit that were stored at regular atmosphere at 10°C. These results demonstrate the potential of low pressure storage as an effective technique to manage capsicum fruit quality, however, there was no additional benefit when fruits were stored at low pressure for more than 5 days.]]> Fri 31 Jan 2020 11:56:09 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33404 Catharanthus roseus leaf have been used for the extraction of alkaloids, which results in a significant amount of waste that includes the stems, roots, and the extracted leaves. This study aimed to determine the optimal extraction conditions, by applying response surface methodology with Box–Behnken design to assess the interactive effect of ultrasonic parameters, including ultrasonic temperature, time, ratio of sample‐to‐solvent, and ultrasonic power on the extraction efficiency of saponins and antioxidants from the stems of C. roseus. The results revealed that a maximized saponin yield (138.21 mg ESE/g) and strong antioxidant activities (8.34, 12.06, 10.53, and 19.15 mg TE/g for DPPH, ABTS scavenging capacity, FRAP, and CUPRAC, respectively) could be obtained under the optimal extraction conditions: ultrasonic temperature of 55 °C, ultrasonic time of 35 min, sample‐to‐solvent ratio of 1/100 (g/ml), and ultrasonic power of 150 W. Practical applications: Recovering bioactive compounds from Catharanthus roseus stems, especially saponins which have been linked with various biological activities such as antimicrobial, antiherbivore, and/or cytotoxic activities, is necessary to avoid wasting bioresource from the alkaloid exploration of the leaves. This study suggested the optimal ultrasonic conditions that could be used for further extraction and isolation of saponins from C. roseus stems for potential application in the food, nutraceutical, cosmeceutical, and pharmaceutical industries.]]> Fri 26 Oct 2018 16:04:20 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:46556 Fri 25 Nov 2022 11:33:45 AEDT ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33067 Sargassum vestitum, Sargassum linearifolium, Phyllospora comosa, Padina sp., Hormosira banksii and Sargassum podocanthum, were investigated for the chemical profile and antioxidant activity. The results showed that the extracts H. banksii, S. vestitum and Padina sp. indicated the significantly higher total phenolic compound (TPC) and antioxidant activities (ABTS, DPPH and FRAP) compared to the other species (P < 0.05) and comparable to positive controls: butylated hydroxytoluene, ascorbic acid and alpha‐tocopherol at the concentrations (0.06–1 mg mL−1). Fucoxanthin was also found in six species and isolated for evaluating antioxidant activity. In addition, the phenolic compounds were mainly responsible for antioxidant activity of the extracts, while fucoxanthin showed quite high antioxidant activity. It is suggested that S. vestitum, H. banksii and Padina sp. have the potent for extracting bioactive components and further applications in food and pharmaceutical industries.]]> Fri 24 Aug 2018 13:45:12 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33071 Hormosira banksii is a rich source of polyphenols, which can be utilized in the food or pharmaceutical industries. This study aimed to determine the impact of six drying methods on properties of the alga H. banksii. Our data revealed that drying conditions significantly affected recovery yield, residual moisture, extraction yield, total phenolic content (TPC) as well as antioxidant capacity of H. banksii (P < 0.05). Optimal conditions for oven, vacuum and de‐humidification were 40, 50 and 50C, respectively, and microwave power is 840 W. Under optimal conditions, H. banksii prepared by freeze, de‐humidification and vacuum had significantly higher levels of TPC, total flavonoid content (TFC) and proanthocyanidins as well as possessing stronger antioxidant capacity in comparison with those prepared by sun, microwave and oven drying methods. As freeze drying is costly and time‐consuming, de‐humidification (50C, air in and out of 11.1 and 15.4%) and vacuum (50C, 10 psi) were recommended for drying H. banksii. Practical Applications: Algae possess various antioxidants with potential benefits for health. Drying is considered as a method for preserving materials, transport with low costs and especially first step for extraction, isolation and purification of active compounds. Thus, it is important to investigate the effects of drying conditions on the properties of the dried alga H. banksii. From the findings, the different drying conditions significantly affected the phytochemical profile and antioxidant activity of the dried alga and the optimal drying conditions could be applied for preparation of dried H. banksii for further processing (extraction, fractionation and isolation of bioactive compounds) as well as potential industrial applications (as a reference for drying H. banksii and other algae).]]> Fri 24 Aug 2018 13:45:06 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33068 Hormosira banksii for total phenolic content (TPC) and antioxidant activities including total antioxidant capacity (ABTS), DPPH free radical scavenging capacity (DPPH) and ferric reducing antioxidant power (FRAP) using response surface methodology (RSM). Box–Behnken design was employed to assess the effect of ultrasonic temperature, time and power on the TPC and antioxidant activities of the extracts. The results showed that RSM was an accurate and reliable method in predicting TPC and antioxidant activities (ABTS, DPPH and FRAP) of the extracts with R² values of 0.97, 0.96, 0.92 and 0.94, respectively. The ultrasonic temperature and time had the significant impact on TPC and antioxidant capacities. The optimal UAE conditions for the maximal values of TPC and antioxidant activities were of 30 °C, 60 min and power 60%, or 150 W. The values of TPC and antioxidant activities (ABTS, DPPH, FRAP) achieved under these parameters were 23.12 (mg GAE g⁻¹), 85.64 (mg TE g⁻¹), 47.24 (mg TE g⁻¹) and 12.56 (mg TE g⁻¹), respectively. UAE was found to be more efficient in comparison to conventional extraction, with shorter time for extraction and higher of TPC level and antioxidant activities. Therefore, ultrasonic-assisted extraction using RSM is effective for extraction and further isolation and purification of phenolic compounds from H. banksii. In addition, this alga could be a potential rich source of natural antioxidants applied in food and pharmaceutical fields.]]> Fri 24 Aug 2018 13:44:59 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33066 Fri 24 Aug 2018 13:44:52 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33063 Fri 24 Aug 2018 12:56:06 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:33060 Phyllanthus amarus. The findings indicated that the optimal MAE parameters consisted of 100% methanol, irradiation time 4 s/min, extraction time 50 min, and solvent to sample ratio 50 mL/g. Under these optimal parameters, saponin content (SC), saponin extraction efficiency (SEE), and total phenolic content (TPC) of P. amarus were 229.5 mg escin equivalents (EEs)/g dried sample, 82.8%, and 40.7 mg gallic acid equivalents (GAEs)/g dried sample, respectively. The antioxidant capacity of P. amarus in terms of 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging capacity (ARSC), 2,2-diphenyl-1-picryl-hydrazil radical scavenging capacity (DRSC), and ferric reducing antioxidant power (FRAP) were 487.3, 330.6, and 233.5 mg trolox equivalents (TEs)/g dried sample, respectively. These measured values were not significantly different from the predicted values by response surface methodology (227.9 mg EE/g dried sample, 82.1%, and 39.2 mg GAE/g dried sample for SC, SEE, and TPC and 484.8, 297.3, and 226.6 mg TE/g dried sample for ARSC, DRSC, and FRAP, respectively). Hence, the optimal MAE parameters are suggested for effective extraction of saponins from P. amarus for further investigations and applications.]]> Fri 24 Aug 2018 12:55:58 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:47830 Fri 23 Jun 2023 12:02:28 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:40015 Helicteres hirsuta Lour. (H. hirsuta) has been traditionally used in many countries for the treatment of various ailments, indicating that it contains potential therapeutic agents. This study aimed to derive different fractions from the saponin-enriched extract of H. hirsuta stem using RP-HPLC and examine the in vitro anti-pancreatic cancer activity of the derived fractions (F0–F5). With the exception of F0, the five fractions (F1–F5) possessed strong inhibitory activity against PC cells at IC50 values of 3.11–17.12 μg/mL. The flow cytometry assays revealed the active fractions caused cell cycle arrest at S phase and promoted apoptosis in MIAPaCa-2 PC cells. The LC/MS analysis revealed that the isolated fractions contained bioactive compounds, such as caffeic acid, rosmarinic acid, sagerinic acid, usnic acid, cucurbitacins and absinthin. It can be concluded that the fractions isolated from H. hirsuta stem exhibit potent in vitro anti-pancreatic cancer activity and thus warrant further in vivo studies to assess their activity against PC followed by isolation of individual bioactive compounds and the evaluation of their anti-pancreatic cancer activity.]]> Fri 22 Jul 2022 13:06:36 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:41730 Fri 12 Aug 2022 10:39:26 AEST ]]> https://nova.newcastle.edu.au/vital/access/manager/Repository/uon:34478 Catharanthus roseus (L.) G. Don (C. roseus) is well known as an important medicinal plant, with compounds such as the vinca alkaloids isolated for their anticancer activity. As such, it is important to determine the effective solvent for bioactive compound extraction from this plant and the suitable drying methods for preparation of starting material. The aims of this study were to determine the effect of extraction solvents and drying methods on bioactive compounds and antioxidant properties of C. roseus. Water was found to be the optimal solvent for phenolic and flavonoid extraction; whereas, methanol was the best solvent for saponin and proanthocyanidin extraction. The data also revealed that vacuum drying at 50°C was suitable for drying the leaf and the flower which contained high levels of phenolics and flavonoids, while infrared drying at 35°C was recommended for drying the stem and the root which had high saponin content. Practical applications: This study suggested that different parts of C. roseus had different suitable thermal drying methods. For the leaf and the flower, vacuum drying at 50°C was the optimal drying method, whereas infrared drying at 35°C was suitable for drying the stem and the root. These drying conditions can be easily applied for preparation of dried plant parts with high levels of bioactive compounds in the large scale. Importantly, the data indicated that the stem and the root of C. roseus which were considered as waste when the leaf was used for exploiting alkaloids, possessed great content of saponins. Therefore, these parts can be further used for isolation and purification of saponins.]]> Fri 03 Dec 2021 10:35:25 AEDT ]]>