The following ten species collected from the air of Seoul City and the soils in Korea are reported as undescribed to Korean fungal flora: Cladosporium sphaerospermum, C. herbarum, C. colocasiae, Alternaria chlamydospora, A. cheiranthi, A. citri, Curvularia ovoidea, C. inaequalis, C. affinis, and Eurotium repens.

Interspecific hybrids of Pleurotus ostreatus and Pleurotus florida were formed by using protoplasts of complementing auxotrophs. The genetic markers were shown to segregate and recombine in the first generation of monosporus isolates from basidiocarp of seven fusion products. The analysis provides proof of heterokaryosis and strong evidence for haploidy of vegetative nuclei, a sexual cycle consisting of nuclear fusion and meiosis. In all the crosses there was no evidence of linkage between the genetic markers. Clamp connections were formed in monosporus mycelia from basidiocarp of fusion products.

The mating system of monokaryotic isolates in Pleurotus sajor-caju was controlled by two incompatibility factors A and B of tetrapola mating system. The mycelia of dikaryotic isolates grew faster than those of their component monokaryons, but no correlation between dikaryotic and their component monokaryotic isolates was found. The primodia formed well on the potato dextrose agar (PDA) media not only in the dikaryotic isolates but also in the monokaryons under irradiated conditions. The dikaryotic isolates produced normal sporophores; however, the monokaryotic isolates produced abnormal sporophores when they were cultivated with sawdust substrates. Some dikaryotic isolates derived by mating between monokaryotic isolates showed high yields of sporophores more than those of parental strains. Both the dikaryotic mycelial growth rate and primodia formation number on the PDA plate showed significant correlation with its sporophore products on sawdust substrates.

The purposes of this study were to investigate enzyme components and its physiological activities of Sarcodon aspratus (Berk.) S. Ito which grows wildly in Korea, belonging to the family Thelephoraceae. The carpophores of the fungus was extracted with cooling distilled water and salted out by ammonium sulfate. The precipitate was purified by dialysing through visking tube against distilled water and then dissolved with pH 7.8 ammonia aqua, and the extract was filterated. The fraction of filtrate was obtained as light brown powder after lyophilization and determined proteolytic activity. Protease activity of Sarcodon aspratus (Berk.) S. Ito was about two-third of that of pepsin on casein by cup method. The proteolytic potency of this enzyme was found to be 500 unit/mg. This proved the efficacy of the mushroom when it was used as a folk medicine for treating indigestion of beef.

The volatile aroma concentrates were isolated from Pleurotus ostreatus by simultaneous distillation-extraction and analyzed by gas chromatography and combined gas chromatography-mass spectrometry. The aroma concentrates obtained had a typical raw or slightly cooked mushroom-like odor, and the yield was 123 ppm. Of 27 components identified, the major components were 3-octanone, 3-octanol, 2-octenal, n-octanol and 2, 4-decadienal, including 1-octen-3-ol contributing 67.06% of the total volatiles, and the compounds comprised about 80% of the total volatiles. On the other hand, the and alcohols in mushroom increased gradually with increase of standing time after homogenation, while aldehydes, ketones, and linoleic acid decreased, and also and compounds were significantly increased when linoleic and linolenic acid were added in homogenates. It appears that most of volatile aroma components in Pleurotus ostreatus were probably produced enzymatically from unsaturated fatty acids containing cis, cis-1, 4-pentadiene moiety.

The production of cellulolytic enzymes by Pleurotus sajor-caju JAFM 1017 was stimulated by folic acid and thiamine-HCl. Among the inorganic salts, optimum concentrations of and were 0.2% (w/v) and 0.04% (w/v), respectively, but other inorganic salts were not effective for the production of the enzymes. The optimum culture temperature and pH for the production were and 5.5 for avicelase, and and 5.0 for CMCase, and and 6.5 for , respectively.

Among the representative phenolic compounds in relation to lignin derivatives and protein synthesis inhibitors, the most effective inducer for the extracellular polyphenol oxidase (PO) of Lentinus edodes JA01 was gallic acid and ferulic acid for Pleurotus ostreatus. Optimum concentration of these inducers was 2.0 mM and 1.0 mM, respectively. Addition of gallic acid after two days culture had the best effect on production of PO enzyme of L. edodes JA01 and for P. ostreatus, and addition of ferulic acid after three days culture had the best effect. Also, in case of L. edodes JA01, polyphenol oxidase activity was parallel to growth curve, whereas the maximum enzyme activity of P. ostreatus was shown at exponential growth phase and declined thereafter.

To examine safety of Ganoderma lucidum, it was extracted with hot water (Fraction A). After the extract was dialyzed and freeze-dried, a polysaccharide fraction (Fraction B) was obtained and examined for acute and subacute toxicity. In the acute toxicity tests of Fr. A and Fr. B on mice, both agents did not show any serious and lethal effects. The results showed that 50% lethal doses were higher than 5,000 mg/kg. The experiments of oral administration of Fr. A (5,000 mg/kg) to mice for 30 days showed that there were no changes in body weight, hematological features and organ weight.

Sterigmatocystin bears a close structural relationship to aflatoxin and is a carcinogenic compound that has been shown to affect various species of experimental animals. Reaction and toxicity of sterigmatocystin in the artificial gastric juice were investigated. Sterigmatocystin was degraded in artificial gastric juice and extracted by the method of A.O.A.C. After cleaned up by silica gel column chromatography, this substance was detected and characterized by thin layer chromatography, UV, IR and mass spectra. It showed 0.4 and brick-red color by TLC. Especially, in the mass spectrum of it, fragment peak at m/e 327 was due to the loss of the and , fragment peak at m/e 341 was due to the loss of the and , and fragment peak at m/e 239 was due to the loss of the 2-chloro-tetrahydrofuran and methyl group from the parent molecule. Therefore, a degraded substance of sterigmatocystin reacted in artificial gastric juice (Sub. K) was estimated with additional formation of hydrochloric acid. In four-day-old chicken embryos, the mean lethal dose was , and 90 to 100% of the embryos were killed with 1 mg/egg. This compared with an for sterigmatocystin (acute toxicity) showed the substance to be much less toxic than sterigmatocystin.

Of the 1,200 single spore isolates of Alternaria mali causing apple leaf spot and fruit decay, the mycelial colonies showed 76, 96 and 15% growth at 100,000 of captafol, chlorothalonil and folpet, respectively, and five and three percent growth at 10,000 of iprodione and polyoxin. These isolates showed cross-tolerance of mycelial growth, spore formation, or spore germination to the above five fungicides plus captan, garbenda, and thiophanate methyl. Captafol, mancozeb, polydong, and propineb did not show any cross-tolerance of spore germination since no spore was germinated at 100 which was much lower than the concentration used by apple growers. Benomyl, fenarimol, oxidong, and triademefon showed medium degree of cross-tolerance of the fungal growth, sporulation, and spore germination.

A cellulose-degrading enzyme from Ganoderma lucidum was partially purified by ammonium sulfate precipitation and its enzymatic properties were studied. The enzyme had an optimum pH for activity at 4.0, and its stability range was pH . The optimum temperature was and the enzyme retained 80% original activity after heated at for 60 min. The activation energy of the enzyme for CMC degradation was caculated and found to be 6.2 Kcal/mole. The enzyme was activited by the addition of , but slightly inactivated by . Various enzyme inhibitors and chemical reagents did not affect the enzyme activity. The enzyme acted on native celluose as well as CMC. The Michaelis constant for CMC was calculated to be 2.4 mg glucose ep/ml.

More than 40 samples of the genus Cordyceps were collected and investigated. Among them, six species were confirmed as unrecorded ones in Korea. Unrecorded species were Cordyceps alboperitheciata, Cordyceps discoideocapitata, Cordyceps intermedia, Cordyceps nigrella, Cordyceps roseostromata and Cordyceps scarabaeicola.

Sixteen seed samples of nine vegetable crops imported from Japan were tested for plant quarantine by routine methods of seed health testing. Nineteen species of fungi including Alternara alternata were identified from the seed samples. Some species were very frequently detected in the seeds. In this experiment, Verticillium albo-atrum, V. dahliae and Macrophomina sp. from the seeds of spinach, and Cercospora capsici, Drechslera hawaiiensis and V. albo-atrum from the seeds of sweet pepper were detected for the first time, respectively. It has been reported that they had a pathogenicity on some vegetable crops in Japan and other countries. The data suggest that an epidemic damage may be occurred if the infected seeds are sown and cultivated in Korea.