https://nova.newcastle.edu.au/vital/access/ /manager/Index ${session.getAttribute("locale")} 5 https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:30608 Eucalyptus and traditionally, many Eucalyptus species have been utilised to heal wounds and treat fungal infections by the Indigenous people of Australia. In view of this, our study was designed to investigate the phytochemical, antibacterial and antifungal properties of crude aqueous extract of E. microcorys leaves. The freeze-dried powdered extract was prepared and the phytochemical profile was studied by analysing the total phenolic content (TPC), total flavonoid content (TFC), proanthocyanidins, antioxidants and saponins. The TPC, TFC and proanthocyanidin values found were: 501.76 ± 14.47 mg of gallic acid equivalents per g, 61.53 ± 0.83 mg of rutin equivalents per g and 10.76 ± 0.89 mg of catechin equivalents per g, respectively. The antioxidant values expressed in mg trolox equivalents per g of extract (mg TE/g) were: ABTS = 1073.13 ± 10.73 mg TE/g, DPPH = 1035.44 ± 65.54 mg TE/g and CUPRAC = 1524.30 ± 66.43 mg TE/g. The powdered extract was also evaluated for activity against three pathogenic bacterial strains (Escherichia coli, Enterobacter aerogenes, Staphylococcus lugdunensis); and three fungal strains (Geotrichum candidum, Aspergillus brasiliensis and Candida albicans) using the disc diffusion method and 96 well plate-based method with resazurin dye. The extract exhibited clear zones of inhibition against the tested bacteria and fungi. Minimum inhibitory concentration (MIC) values were demonstrated to be: A. brasiliensis = 2.44 μg/mL, G. candidum = 4.88 μg/mL, S. lugdunensis = 78 μg/mL, E. coli = 156.25 μg/mL, E. aerogenes = 312.5 μg/mL and C. albicans = 1250 μg/mL. These results reveal the significant potential of E. microcorys as a source of phenolics, antioxidants and antimicrobial agents and also highlight the necessity of further purification and characterisation of solitary bioactive compounds for their prospective applications in food, nutraceutical and pharmaceutical industries.]]> Tue 01 Oct 2019 13:08:19 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:32711 Fri 20 Sep 2019 02:27:30 AEST ]]>