• Preventive Nutrition and Food Science
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• v.8 no.1
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• pp.75-78
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• 2003

We analyzed the ${\gamma}$-aminobutyric acid (GABA) content of a selection of uncooked foods. Foods with GABA concentrations in excess of 100 nmole per g dry weight included: brown rice germ, brown rice sprouts, barley sprouts, bean sprouts, beans, corn, barley, brown rice, spinach, potatoes, sweet potatoes, yams, kale and chestnuts. Cereals included: brown rice germ, brown rice sprouts, barley sprouts, bean sprouts, beans, corn, barley, and brown rice and had GABA concentrations of 718, 389, 326, 302, 250, 199, 190, and 123 nmole per g dry weight (DW), respectively. The vegetables: spinach, potatoes, sweet potatoes, yams and kale contained 414, 166, 137, 129, 122 nmole GABA per g DW, respectively. The GABA concentration of chestnut was 188 nmole per g DW. However, oatmeal, adlay, broccoli, squash, carrots, onion, apples, lentinus edodes, green laver, and lactobacillus had GABA concentrations of less than 100 nmole per g DW. These results show that brown rice germ, sprouted cereals and spinach are good sources of plant-derived GABA. These data will be useful in selecting foods for the manufacturing of uncooked foods containing a relatively high concentrations of GABA.

• Proceedings of the Korean Society for Bio-Environment Control Conference
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• 2001.04b
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• pp.43-44
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• 2001

Recently the sawdust culture of Lentinus edodes(Berk.) has been gradually extended replacing the log cultivation in Korea. It is indeed able to reduce the use of log and cultivation period in controlled facilities, but is not yet able to produce the high-quality mushroom. The objectives of this study were to examine the effects of low and alternated temperature treatments during the fruiting period on the quality of oak mushroom. At low temperature treatments of 1$^{\circ}C$ and 10$^{\circ}C$, the crack, lightness, hardness, and other characteristics for the high-quality oak mushroom were not improved. However, the crack, brightness, and hardness of cap were increased at alternated temperatures of 5-10$^{\circ}C$ than the other temperature treatments. In conclusion, the alternated temperature treatments were more effective than the low temperature treatment for improving the indices of high-quality oak mushroom such as the crack, brightness and hardness of cap.

• The Korean Journal of Mycology
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• v.17 no.3
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• pp.161-168
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• 1989

Mitochondria in L. edodes were separated and purified by stepped sucrose density gradient centrifugation. In our previous work, we have found that the activation wavelengths of the mitochondrial ATPase and ATP synthase were 680 nm and 470 nm within the range of 400-700 nm, respectively. The activities of the above enzymes with wavelengths of 300-400 nm region were investigated. The mitochondrial ATPase and ATP synthase were stimulated at 380 nm and 330 nm, respectively, for 30 min illumination compared with dark control group. They, however, were inhibited at 330 nm and 350 nm, respectively. The presence of FAD resulted in inhibition of the activity of the ATPase and stimulation of the activity of the ATP synthase by the activation and inhibition wavelengths. However, the activities of these enzymes were not changed by NADH for the above wavelengths. In the spectral properties, the oxidation of $FADH_2$ into FAD occurs in the presence of the enzymes for illumination of the activation and inhibition wavelengths. Therefore, we can predict that the mitochondrial ATPase and ATP synthase may function as oxidant in the redox reaction by the light illumination and that the light-induced pigment of the mitochondrial ATP synthase should be an oxidized form of a flavoprotein.

• Journal of Mushroom
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• v.2 no.4
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• pp.184-191
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• 2004

Mutual growth limitation was observation when the two antagonistic fungi was come in contact with each other. Brown line was formed 2day after contact with Trichoderma spp., and then, green spores formed overnight. The laccase activity of L. edodes was stimulated when this fungus wsa co-incubated with Trichoderma spp. for a few days in liquid media. In sawdust-rice bran nixtures, outstanding broun line developed when the two antagonistic fungi co-cultured. The pH of the substrates changed from 5.5 to 4.5 after overgrowth, suggesting a difference in the degradation ability and the preference of the two fungi for the lignocellulose material.

• Journal of Mushroom
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• v.10 no.3
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• pp.120-128
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• 2012

Recently sawdust cultivation of Shiitake mushroom (Lentinula edodes) is increasing. It is important to make mycelia to be brown on the substrate surface. This browned surface in sawdust cultivation plays an important role like as artificial bark of the oak log, which protects the other pests and suppresses water evaporation in the substrate. In order to isolate genes which related to brown color formation, differential display method was used. Two cDNA fragments obtained by DD-PCR were 1.2 and 1.6kb and these were expressed in white colored mycelia from L. edodes, but not brown colored mycelia. Partial sequencing of these cDNA fragments showed that the 1.6kb cDNA had 100% identity with the microsatellites gene from Dugenia polichroa. However, the other 1.2kb cDNA fragment had poly T tail on 3' region of partial open reading frame on 5' region. The new primer designed based on the sequence of 1.2kb cDNA was constructed. RT-PCR analysis using the newly designed 0.12kb cDNA specific primer showed that the gene was only expressed in white color mycelia, but not in brown color mycelia. Sequence analysis of 5' region of this 1.2kb cDNA revealed that this gene contained partial open reading frame consisted of 110 amino acid. Homology search using DNASIS database showed that this gene had high sequence homology of 66.7% in DNA level and 69.2 % in amino acid level with dTDP-glucose 4,6-dehydratases gene from Arabidopsis thaliata. The dTDP-glucose 4,6-dehydratases gene was known to be function to have tolerance with oxidation stress. These results strongly suggest that this gene isolated from white mycelia of L. edodes might have a function of repressor against mycelia browning. Therefore I designated this gene as BCR (Brown Color Repressor) gene.

• Korean Journal of Microbiology
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• v.49 no.2
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• pp.191-194
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• 2013

The fresh fruit bodies of Pleurotus eryngii var. ferulae was irradiated with ultraviolet (UV)-B (280-320 nm) in order to increase vitamin $D_2$ contents, which was assayed using HPLC (Waters 1525, USA). The vitamin $D_2$ contents were $3.5{\mu}g/g$ after 3 min UV-B irradiation ($21.6KJ/m^2$) and $6.02{\mu}g/g$ after 5 min UV-B irradiation ($36KJ/m^2$), respectively, which showed the significant increase considering the vitamin $D_2$ content ($0.01{\mu}g/g$) before UV-B irradiation. This increasing effect was confirmed also for other edible mushrooms; Pleurotus eryngii, from $0.09{\mu}g/g$ to $2.75{\mu}g/g$ (3 min) and $5.21{\mu}g/g$ (5 min); Lentinus edodes, from $0.021{\mu}g/g$ to $3.02{\mu}g/g$ (3 min) and $3.78{\mu}g/g$ (5 min); Pleurotus ostreatus, from $0.19{\mu}g/g$ to $9.63{\mu}g/g$ (3 min) and $11.6{\mu}g/g$ (5 min). Although the original content of vitamin $D_2$ was the highest in P. ostreatus, the extent of increase by UV irradiation was remarkably high in P. eryngii var. ferulae.

• Journal of Mushroom
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• v.14 no.1
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• pp.1-5
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• 2016

To minimize cultivation costs, prevent insect-pest infestation, and improve the production efficiency of thermophilic mushrooms, plant substrates obtained from local areas in Cambodia were used for production of both spawn and mushrooms. In this experiment, different sawdusts different organic wastes and grain ingredients and analyzed for improvement of spawn-production efficiency. Four thermophilic mushroom species, Pleurotus sajor-caju (oyster mushroom, Sambok), Ganoderma lucidum (deer horn shaped), Auricularia auricula (ear mushroom), and Lentinula edodes (shiitake), were used to identify efficient new substrates for spawn and mushroom production. Although the mycelia in the rubber tree sawdust medium showed a slightly slower growth rate (10.9 cm/15 days) than mycelia grown in grains (11.2 cm/15 days in rice seeds), rubber tree sawdust appeared to be an adequate replacement for grain spawn substrates. Th findings indicate that rubber tree sawdust, sugarcane bagasse, and acacia tree sawdust supplemented with rice bran and calcium carbonate could be new alternative the substrates for. Although sugarcane bagasse and rubber tree sawdust showed similarly high biological efficiencies (BE) of 60% and 60.8%, respectively, acacia tree sawdust exhibited relatively a low biological efficiency of 22.4%. However, it is expected that acacia sawdust has potential for the mushroom cultivation when supplemented with currently used sawdust substrates in Cambodia, because of its relatively low price. The price of the sawdust (20 kg sawdust= 6500 Riel or 1.6 USD) currently used was 6.5 times higher than the price of acacia sawdust (201000 Riel or 0.25 USD). Therefore, utilization for acacia sawdust for mushroom cultivation could become feasible as it would reduce by producing costs of mushrooms in rural areas of Cambodia.

• Korean Journal of Food Science and Technology
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• v.38 no.2
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• pp.188-196
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• 2006

Changes in physicochemical characteristics and functional components content of saengsik, uncooked food, were investigated to find efficient drying methods, one of important manufacturing process of saengsik. No changes in proximate compositions of all samples were observed during hot-air drying at 50, 55, and $60^{\circ}C$ and freeze-drying. Colors of carrot, Lentinus edodes, and sea mustard did not change, while a value of cabbage, L, a, and b values of Agaricus bisporos, and a value of laver changed slightly by hot-air drying at all temperatures and freeze-drying. Dietary fiber content increased by hot-air drying but not by freeze-drying. Reductions in vitamin C and ${\beta}-carotene$ contents of carrot, cabbage, sea mustard, and laver were higher by hot-air drying than by freeze-drying. Contents of total phenolics and lectin of L. edodes and A. bisporos were not affected by hot-air drying and freeze-drying. Contents of pectin, alginic acid, and porphyran in sea mustard and laver increased by hot-air drying.

• The Korea Journal of Herbology
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• v.23 no.2
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• pp.137-143
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• 2008

Objectives : Cheonggukjang(natto) is known to have anti-hyperlipidemic action in our previous study. This study was designed to investigate the safety of Prototype-cheonggukjang (PC, Herbal-natto). Methods : We investigated the effects of PC on changes in body weights, food uptake, water uptake, levels of AST/ALT, levels of BUN/creatinine and electrolytes in serum from normal mice. PC is made by cheonggukjang added Codonopsis Lanceolata, Houttuynia cordata and Lentinus edodes in indicated concetrations. Results : In this experiment, PC group showed equal levels of body weights, urine volume compared to non-treated control group. Oral administration of PC did not affect food and water uptake too. Levels of AST/ALT, which are markers of liver function, were not changed by administration of PC. In addition, levels of BUN/creatinine, which are markers of renal function, were not affected by PC too. Finally electrolytes in serum were not affected by PC. Conclusions : These results imply that oral administration of PC is safe in the framework of liver and renal function, and electrolytes in serum.

• Journal of Microbiology and Biotechnology
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• v.8 no.2
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• pp.129-133
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• 1998

The white-rot fungi Phanerochaete chrysosporium ATCC 24725, Pleurotus ostreatus ATCC 32783, Lentinus edodes ATCC 24462, and Trametes versicolor ATCC 42530 were studied for their ability to degrade lignin, phenanthrene, and anthracene. Lignin in rice-straw was degraded by 14.4, 28.73, and 33.88% by P. chrysosporium, T. versicolor, and P. ostreatus, respectively. Approximately 12% and 83% of phenanthrene was degraded in 1 and 5 days, respectively, when the pre-grown mycelIium matrix of P. ostreatus. was incubated with 10 ppm of phenanthrene in modified Kirk's medium (nitrogen limited) at $25^{\circ}C$. Approximately 2%> and 61% of phenanthrene was degraded when the phenanthrene concentration was increased to 30 ppm. Similar trends were observed with phenanthrene using P. chrysosporium. Mycelial growth of T. versicolor was less inhibited at 30 ppm phenanthrene than for P. ostreatus and P. chrysosporium. Better degradation of phenanthrene by T. versicolor may be attributed to better mycelium growth. One hundred percent of 15 ppm anthracene was degraded in 10 days by both P. chrysosporium and T. versicolor. 40 ppm anthracene inhibited the mycelial growth of P. chrysosporium. lignin peroxidase activity, which was previously reported to be involved in initial phenanthrene oxidation, was also detected from the culture broth of the strains tested. The rates of lignin peroxidase production in the cultures were not consistent with the rate of PAH hydrolysis during incubation.