https://ogma.newcastle.edu.au/vital/access/ /manager/Index en-au 5 https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33431 Citrus latifolia) were exposed to 0 and 7.2 kJm^-2 UV-C. After treatments, then stored for 28 days in air at 20°C, 80% RH (control) and in air containing < 0.005 or 0.1 µL.L^-1 ethylene at 20°C and 100% RH. Weight loss, peel colour, calyx abscission, ethylene production, respiration rate, soluble solids content (SSC), titratable acidity (TA) and acceptability index were assessed. The results showed that pre-storage UV-C treatment, followed by different storage conditions significantly affected the quality of limes during storage. UV-C treatment significantly affected peel degreening at 20°C in all storage conditions, whereas treated limes showed significantly slower in peel degrening than the control. These effects reduced over the storage time, with the exception of fruits stored in < 0.005 µL.L^-1 ethylene which still produced a significantly higher in Hue value after 21 days storage relative to the control. UV-C treatment affected ethylene production during storage under all storage conditions. This effect also diminished with storage time. UV-C treatment did not affect the respiration rate, SSC or TA for all storage conditions. The UV-C treated limes had higher acceptability index than untreated limes up to 14 days storage at 20°C. Storage conditions significantly affected ethylene production, with limes that stored in air exhibiting higher ethylene production than fruits stored in the < 0.005 or 0.1 µL.L^-1 ethylene atmosphere. Storage conditions also significantly affected weight loss, with fruits stored in air showing greater weight loss compared to the other storage conditions. The results suggest that a pre-storage UV-C treatment, followed by storage in less than 0.1 µL.L^-1 ethylene atmosphere improves the quality of limes postharvest.]]> Wed 31 Oct 2018 15:20:11 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33425 Wed 31 Oct 2018 15:05:14 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36365 Wed 29 Apr 2020 14:12:05 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43695 12 hr > 6 hr with citral having greater reduction of fungal wastage than linalool. Fumigation with limonene showed no antifungal activity. Citral did not show full inhibition of green mould decay in Navel oranges, however the treatment did not cause fruit’s rind injury. It would be worthy to conduct further research as fumigation with citral has potential to provide an alternative decay control or green mould in citrus fruit.]]> Wed 28 Sep 2022 09:33:57 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43924 -1) against both A. alternata and A. citri. The results showed that lemon aqueous extracts suppressed the mycelial growth and spore germination of both species in a concentration-dependent manner. The mycelial growth inhibition (MGI) for A. alternata varied between 31 to 68%, while for the A. citri the MGI varied between 14 to 49%. Scanning electron microscopy showed that lemon waste extracts affected the morphology of both species.These results indicate that the aqueous extracts of lemon by-products contain bioactive compounds which could be potentially useful as an alternative to synthetic fungicides for controlling Alternaria.]]> Wed 05 Oct 2022 10:31:22 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36239 Tue 17 Mar 2020 12:32:29 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:48306 Tue 14 Mar 2023 14:34:38 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:43099 Tue 13 Sep 2022 12:40:25 AEST ]]> https://ogma.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://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:44712 -2 UV-C irradiation at 20°C. After treatment, tomatoes were stored in continuous air containing either < 0.005 or 0.1 µL L^-1 ethylene at 20°C and 100% RH for up to 11 days. The untreated fruit (0 kJm^-2 UV-C) ripened significantly faster than UV-C treatments for both storage conditions. UV-C treatments followed by storage at both of < 0.005 and 0.1 µL L^-1 ethylene had significantly slower ethylene production rates throughout the ripening period. There was no difference between treatments in fruit TSS, TA and, TSS/TA ratio. After storage, treated fruits with 10.5 and 13.6 kJm^-2 UV-C were significantly firmer than untreated fruits for both storage conditions. Overall, tomatoes stored at < 0.005 µL L^-1 ethylene were significantly firmer and higher in TSS/TA ratio than fruits stored at 0.1 µL L^-1 ethylene. These results show that UV-C treatment delayed ripening of tomatoes in the presence of low level of ethylene during storage. In the absence of ethylene, UV-C treatment resulted in higher firmness value, TSS and TSS/TA ratio. This new treatment could be used to extend the shelf-life of mature green tomatoes through the supply chain without the use of refrigeration.]]> Thu 20 Oct 2022 15:06:25 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:44711 Thu 20 Oct 2022 14:31:32 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:44709 -2) and stored for up to 9 days at 20°C or 28 days at 1°C. Fruit quality was assessed by stem colour, stem attachment, development of postharvest rots, flesh colour, fruit firmness, total soluble content and titratable acidity. Fruit exposed to UV-C treatment and storage at 20°C experienced significantly lower levels of postharvest rot, but this response to UVC treatment was not dose dependent. In contrast, UV-C treatment was found to have no significant effect on decay development for treated fruit when later stored for up to 28 days at 1°C. UV-C treatment exhibited no significant impact on stem colour, flesh colour, stem detachment, TSS, TA nor TSS/TA ratio for fruit stored at 20°C, although treated 'Lapin' fruits, showed significantly greater firmness retention relative to the control. Results indicated that under certain conditions, postharvest UV-C treatment has the potential to reduce the incidence of decay and maintaining flesh firmness in sweet cherries stored at ambient temperature (20°C), however, there was no significant effect when stored at 1°C.]]> Thu 20 Oct 2022 14:10:34 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:38263 Thu 19 Aug 2021 15:58:37 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:33532 Solanum tuberosum 'Innovator') were exposed to UV-C light at five different intensities (0.0, 3.4, 7.1, 10.5 and 13.6 kJ m^-2). After treatment, potatoes were stored in the dark in air at 20°C and 80% RH for up to 40 days. During storage the potatoes were assessed for the number and length of each sprout at 10 day interval and at the end of 40 days storage, all sprouts were weighed individually. UV-C irradiation significantly affected the number of sprouts. In the first 20 days of storage, the number of sprouts in irradiated potatoes was significantly lower than untreated tubers, however, this effect diminished during storage. UV-C irradiation also affected the sprout length where irradiated potatoes had significantly shorter sprouts than untreated potatoes during storage of 20 days. Similarly this effect diminished over the storage time. The individual weight of the different sprouts was not significantly different between untreated and irradiated tubers. These results indicate promise for UV-C as a potential postharvest treatment to reduce the incidence of sprouting in potato tubers stored in air at 20°C.]]> Thu 15 Nov 2018 10:18:21 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:36817 Brassica rapa subsp. chinensis) that examined the effect of fumigation with hydrogen sulphide and nitric oxide and subsequent storage at 10°C in air with and without the addition of 0.1 µL L^-1 ethylene. The results showed that treatment with nitric oxide increased the shelf life and decreased respiration rates for the pak choy heads during the storage. However, fumigation with H₂S alone or in combination with NO resulted in greater inhibition of respiration rate and extension in market life, and this effect was more pronounced in the presence of 0.1 µL L^-1 ethylene.]]> Thu 10 Jun 2021 14:07:03 AEST ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:20556 Sat 24 Mar 2018 08:02:35 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:5815 Sat 24 Mar 2018 07:48:01 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:5799 Sat 24 Mar 2018 07:44:53 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:26330 as) of a number of novel polymerisable vinyl biaryl compounds, 4-(4'-ethenylphenyl)-pyridine (M1), 4'-ethenyl-(1,1'-biphenyl)-4-ol (M2), 4'-ethenyl-N,N-dimethyl-(1,1'-biphenyl)-3-amine (M3), 4'-ethenyl-(1,1'-biphenyl)-4-methanol (M4), 4'-ethenyl-N,N-dimethyl-(1,1'-biphenyl)-4-amine (M5), 4'-ethenyl-(1,1'-biphenyl)-4-carboxylic acid (M6), 4'-ethenyl-4-hydroxy-5-methyl-(1,1'-biphenyl)-3-carboxaldehyde (M7) were determined in a mixed solvent (THF-water) potentiometric titration at 25 °C and subsequent extrapolation to pure water via the Yasuda-Shedlovsky method. The acidity and basicity of the compounds in THF-water mixtures was observed to decrease with increasing THF fraction and is attributed to the corresponding decrease in the dielectric constant of the solution. To the best of our knowledge, this is the first reported study of pK_a values undertaken for this class of compounds. The biaryls, M1-M7, were prepared by microwave-assisted Suzuki cross coupling of 4-vinylphenyl boronic acid with the appropriate aryl bromide and were custom designed for use as functional monomers in the synthesis of molecularly imprinted polymers.]]> Sat 24 Mar 2018 07:35:56 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:31025 2S) gas has been found to delay the appearance of many characteristics associated with senescence of horticultural produce but little attention has been given to its physiological role or its interaction with ethylene. This study used the green leafy vegetable, pak choy (Brassica rapa subsp. Chinensis) as the principal test commodity and examined the interaction of fumigation with hydrogen sulphide and storage at 10 °C in the presence of controlled levels of ethylene on endogenous ethylene production and a range of factors associated with postharvest deterioration. It was found that hydrogen sulphide inhibited ethylene production, chlorophyll loss, respiration, weight loss, various antioxidant factors and ion leakage. Hydrogen sulphide also inhibited chlorophyll loss and respiration of other green leafy vegetables/herbs, sweet Italian basil (Ocimum basilicum) and green curly kale (Brassica oleracea var. sabellica). The results suggest that the mode of action of hydrogen sulphide in delaying senescence could be by inhibiting both the production of ethylene and the action of ethylene. The substantial reduction in the rate of loss of chlorophyll following short-term treatment with hydrogen sulphide may have potential commercial benefit for extension in market life of green leafy vegetables.]]> Sat 24 Mar 2018 07:34:52 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:45516 2S) production and has been used to explore the mode of action of H₂S in prolonging storage of horticultural produce but little attention has been given to how PAG and H₂S interact when both are applied to produce. This study examined the effect of sequential application of PAG and H₂S on a range of postharvest senescence factors of the leafy vegetable pak choy (Brassica rapa subsp. Chinensis) stored at 10 °C. The results showed differential responses between factors when compared to application of PAG or H₂S alone. As expected, fumigation with H₂S reduced the rate of loss of leaf green colour, respiration rate, ethylene production, ion leakage and enhanced antioxidant activity and leaves sprayed with PAG showing converse effects. If PAG acted solely by inhibiting endogenous H₂S production then subsequent treatment with H₂S should fully negate any effect induced by PAG. However, for the combined PAG + H₂S treatment, respiration was similar leaves fumigated with H₂S, loss of green leaf colour was similar to the PAG single treatment and less than the untreated control, antioxidant activity was less than for PAG but greater than for control leaves, and ethylene production and ion leakage were similar to control leaves. Thus, the concept that PAG is exclusively an inhibitor of endogenous H₂S production was not validated, with PAG having effects on metabolism that are not linked to the action of endogenous H₂S. The additional actions of PAG could be through its inhibition of pyridoxyal-5′-phosphate (PHP) which is a coenzyme for numerous enzyme systems.]]> Mon 31 Oct 2022 13:48:56 AEDT ]]> https://ogma.newcastle.edu.au/vital/access/ /manager/Repository/uon:46952 Cucumis sativus L.) were stored under low pressure (4 kPa) at 10℃ for 7 and 11 days with 100% RH. Upon removal from low pressure storage and after being transferred to normal atmosphere (101 kPa) at 20℃ for 3 days, fruits were assessed for weight loss, flesh rots, color, firmness and overall acceptability. Fruit weight loss was significantly higher in fruit which stored at low pressure (4 kPa) for 11 days at 10℃ than fruits that were stored at regular atmospheres (101 kPa) at 10℃. The effect of low pressure treatment on fruit weight loss was greater after the additional three days storage at normal atmospheric pressure at (101 kPa) at 20℃. There was no difference in flesh rots, flesh firmness and color retention between fruits stored at low pressure and regular pressure at 10℃ for 7 and 11 days. Cucumbers were stored at regular pressure (101 kPa) 20℃ for 11 days had highest flesh rots and lowest acceptability compared to other treatments.]]> Fri 09 Dec 2022 15:31:41 AEDT ]]>