https://nova.newcastle.edu.au/vital/access/ /manager/Index en-au 5 Microwave irradiation enhances the in vitro antifungal activity of citrus by-product aqueous extracts against Alternaria alternata 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 ]]> Effect of continuous exposure to low levels of ethylene on mycelial growth of postharvest fruit fungal pathogens https://nova.newcastle.edu.au/vital/access/ /manager/Repository/uon:33430 -1, on the growth of fungi isolated from five climacteric fruits (persimmon, pear, tomato, mango and papaya), and three non-climacteric fruits (orange, grape and blueberry). All fungi isolated from climacteric fruits had reduced mycelial growth when held in 0.1 and 1 µL L-1 ethylene but those from non-climacteric fruits showed no effect of ethylene. The finding was unexpected and suggests that fungi that colonise climacteric fruits are advantaged by delaying growth when fruits start to ripen. Since non-climacteric fruits do not exhibit any marked increase in ethylene, colonising pathogens would not need such an adaptive response.]]> Tue 03 Sep 2019 18:08:23 AEST ]]>