• Journal of the Korean Society of Food Science and Nutrition
• /
• v.23 no.2
• /
• pp.315-321
• /
• 1994

In order to prevent the postharvest decay and to promote the freshness retention of fruits and vegetables grapefruit seed extract(GFSE), natural microorganism control agent, was applied to the preservation of fresh fruits and vegetables. Freshfruits and vegetables treated with GFSE and stored in polyethylene film (0.1mm) at 1$0^{\circ}C$-15$^{\circ}C$ of natural low temperature low kept better qualities in color and texture than the GFSE -not- treated control. The treatment using GFSE ina 250ppm to 500ppm concentration seemed to be an effective one for the control of Botrytis cinerea isolated in red wine grapes. After 4 weeks of storage the firmness rate of cucumbers treated with the dilute GFSE was four times higher than that of non-treated ones. GFSE showed effective inhibitory action towards plant pathological bacteria and fungi which were involved in the decay of fruits and vegetables. Minimum inhibitory concentrations of GFSE towards them were in the range of 250ppm to 500ppm .Direct visualization of microbial cells and spores using electron microscopy showed microbial cells and fungal spores the function of which was destroyed by treating with the dilute solutions of GFSE. It was observed that GFSE would reduced disease damages and have bactericide & fungicide properties during the storage of such fruits and vegetables as egg plant, wild edible greens , kumquat, and kiwi fruit.

• Korean Journal of Food Science and Technology
• /
• v.28 no.5
• /
• pp.865-869
• /
• 1996

Biological effect of aqueous extracts of 12 plants which showed superoxide dismutase (SOD)-like activity in vitro was evaluated using Drosophila melanogaster. Survival percentage of the flies was a criterion of effect when the flies were exported to paraquat, which generated superoxide anion radical in vivo. When flies were co-administered with paraquat and aqueous extracts of garlic, lettuce, kiwi, and nameko, they showed no defensive effect against of oxygen toxicity. If flies were exposed to 60 mM paraquat after adaptation to feed containing plant extracts with SOD-like activity for 10 days, however, survival percentage of flies fed with phytochemicals was $35{\sim}63%$ while that percentage of flies fed without phytochemical was only 11%. This result indicated that adaptation of flies to plant extracts with SOD-like activity could prevent the flies from oxidative injury. On the other hand, lettuce, kiwi, nameko, onion, persimmon, fern brake and cauliflower showed a reparative effect on an oxidative stress. Dropwort, shiitake, agaric mushroom and broccoli did not show such an effect.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.18 no.6
• /
• pp.478-485
• /
• 2017

The effect of high carbon dioxide and ethylene treatment on postharvest ripening regulation of red kiwifruit (Actinidia melanandra) was investigated during cold storage. Physio-chemical properties such as weight loss, firmness, SSC, acidity, and market quality were analysed in red kiwifruit held at $10^{\circ}C$ compared to the fruit treated with carbon dioxide and ethylene during 75 days of storage. No significant weight loss was detected in red kiwifruit treated with carbon dioxide until 75 days of storage while the most rapid loss was found in fruit treated with ethylene. In ethylene-treated fruit, the firmness was dramatically reduced from 4.2kg on the first day to 1.2 kg after 27 days of storage at $10^{\circ}C$. However, the firmness of the carbon dioxide-treated fruit was 1.8kg after 54 days of storage. The highest level of SSC(%) was investigated within the 27 storage days at $10^{\circ}C$ for fresh red kiwifruit treated with exogenous ethylene, whereas the carbon dioxide-treated fruit exhibited a greatly increased SSC after 64 days. The carbon dioxide-treated red kiwifruit maintained statistically(p<.01) higher levels of acidity compared to the control and the exogenous ethylene-treated ones during 41 days of storage at $10^{\circ}C$. The SSC/Acid ratio of fruit treated with carbon dioxide was significantly lower (p<.01) maintained than the other two treatments (ethylene-treated and control fruit)throughout the 75-day experiment. Based on the quality characteristics of postharvest red kiwifruit, it could be concluded that the carbon dioxide treatment significantly delayed the ripening process and maintained the market quality of harvested red kiwifruit, which can be a potential application for commercial use in the kiwi industry.