• Journal of the East Asian Society of Dietary Life
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• v.24 no.1
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• pp.101-108
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• 2014

This study was conducted in order to compare the biological activities of water extracts and sugar immersion extracts of green pepper (Capsicum annuum L.), purslane (Portulaca oleracea L.) and shiitake (Lentinula edodes (Berk.) Pegler) by measuring total polyphenol and flavonoid contents, antioxidant activities and inhibitory effects on ${\alpha}$-amylase and ${\alpha}$-glucosidase. The contents of total polyphenols and flavonoids were higher in water extracts than in sugar immersion extracts. The anti-oxidative activities of water and sugar immersion extracts were measured using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging activity assay and reducing power assay. All extracts scavenged radicals in a concentration-dependent manner, and water extracts showed stronger radical scavenging activity and reducing power than sugar immersion extract. However, they all exhibited lower activities than ascorbic acid. Compared to the anti-diabetic drug acarbose, which was used as a positive control, the two types of extracts exhibited low ${\alpha}$-glucosidase inhibitory activities, although the activity of sugar immersion extracts were 2-fold higher than that of water extracts. ${\alpha}$-Amylase inhibitory action was not observed for any of the extracts. Finally, by cytotoxicity test, we confirmed that sugar immersion extracts were safer than water extracts. These results indicate that water extracts and sugar immersion extracts of green pepper, purslane and shiitake have different advantages in terms of their antioxidant and anti-diabetic effects, respectively.

• The Korean Journal of Mycology
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• v.34 no.2
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• pp.73-78
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• 2006

Attempts were made to investigate the physiological and genetic changes when two different shiitake (Lentinula edodes) strains are mixed. Mycelial growth of KFRI 180 strain and KFRI 1 strain were investigated 82 mm and 80 mm, respectively. Concerning the weight loss percentage of medium, KFRI 1 strain decreased 2.4% and KFRI 180 strain 1.6%. Plug-shaped spawn had no-problem to incubate and there were no differences among the ratios of mixture. Also, conditions of plug-shaped spawns were similar, When the isolated mycelia from plugshaped spawns was incubated again, KFRI 1 50%-KFRI 180 50% showed decreased growth of mycelia compared with other treatments. The same results were obtained from test tubes filled with sawdust. When surface of spawn bottles were observed, KFRI 1 50%-KFRI 180 50% showed spots, but other treatments were not different from KFRI 1 and KFRI 180. Test was made to confirm the strains by confrontation culture. The mixture of two strains was proved to be KFRI 1 regardless the ratios of mixture. However, by the RAPD primer analysis, when KFRI 1 was mixed with KFRI 180, KFRI 180 was stronger. Thus, the confrontation line on PDA was different from the bands analysis by primers. Attempts were made whether the fruit-bodies were made at the generating condition of spawn bottles. The results were that KFRI 1 100%, KFRI 1 90%-KFRI 180 10%, KFRI 1 80%-KFRI 180 20%, KFRI 1 50%-KFRI 180 50% treatment showed fruit-body formation. The shape of fruit-body was deformed, but the gill was made normally.

• Journal of Mushroom
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• v.20 no.3
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• pp.138-146
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• 2022

To optimize initial cooling conditions, forced-air cooling was applied to freshly harvested oak mushrooms at 2 levels (0℃ for 30 minutes, at 0℃ for 1 hour) followed by room cooling at 3 levels (-3℃ for 1 day, 0℃ for 1 day, 3℃ for 1 day). After initial cooling, the oak mushrooms were packaged with PVC film, then held in a storage room at 1℃ for 6 weeks. Quality characteristics and percentage marketability were then investigated. As a control, Mushrooms were placed in storage with no initial cooling. The quality factors impacting marketability of fresh oak mushrooms were color change and appearance of decay. Off-odor did not occur or developed only slightly, so it did not affect oak mushroom quality within 6 weeks of low temperature storage. In all treatment groups, the shelf life in which 100% marketability was maintained was up to 3 weeks. At week 5, percent marketability of the 3 treatment groups 1 hour room cooling treatment at 0℃, 1 hour forced air cooling, and control was 100%. 80% In the group that underwent 30 min forced air cooling retained 80% marketability, and the group exposed to 1 day in room cooling at -3℃ retained 86.7% marketability. At week 6 of 1℃ storage, the marketability ratio was 80% in the 1 day room cooling at 0℃ group, 66.7% in the 1 day room cooling at 3℃ group, 46.7% in the 1 hour forced air cooling group, and 33% or less in all other treatment groups. Therefore, the most suitable initial cooling parameter to extend shelf-life of oak mushrooms is 1 day of in room cooling at 0℃ immediately after harvest.