• Korean Journal of Food Science and Technology
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• v.46 no.6
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• pp.739-742
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• 2014

This study investigated the effect of perforation by the Indian meal moth (Plodia interpunctella) larvae on various flexible food-packaging films, in relation to their thickness and type. Among the various flexible packaging films, polyethylene (PE), aluminum foil (AF), polypropylene (PP), polystyrene (PS), and polyethylene terephthalate (PET) were selected for this study due to their wide usage in food packaging. Based on their thickness, film penetration by P. interpunctella larvae was measured as in following order: PP, $20{\mu}m$; AF, $9{\mu}m$; PET, $12{\mu}m$; PP, $30{\mu}m$; PS, $30{\mu}m$; PE, $40{\mu}m$; PE, $35{\mu}m$; PS, $60{\mu}m$; and PET, $16{\mu}m$. P. interpunctella larvae rapidly penetrated through the packaging films regardless of their thickness and type. In particular, it was observed that PP of $20{\mu}m$ and PS of $30{\mu}m$ were completely penetrated by P. interpunctella larvae within 72 h, rendering thin PP and PS films less valuable as anti-insect packaging films. Our results show that the perforations by P. interpunctella larvae were observed in the thin films. These results imply that each packaging film has a marginal thickness against the perforations by P. interpunctella larvae.

• International Journal of Industrial Entomology and Biomaterials
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• v.15 no.2
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• pp.157-160
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• 2007

Nymph of the emma field cricket, Teleogryllus emma, were reared on several types of artificial diets. The development period of nymphs were 55.4 days when only a single food, wheat bran, was provided, and it did not show a significant difference compared to the rearing results of the Danong diet and mixed diet. The supplying period of fish meal as the animal feed, the high emergence rates were obtained at 3rd instar with 90% and 4th instar with 100%. For the added amount test, when more than 40% of the diet was added, it confirmed that the insect weight increased. The characteristics of development according to each added amount of the vegetable food (dry bean-curd residue and corn powder) were investigated to minimize the dangers of the degeneration of diet when rearing with a single feed during the $1st{\sim}3rd$ instar period. First, as the added amount of bean-curd residue increased, nymphal development period became longer and the emergence rate became low. With corn powder as the single diet, all died before becoming adult. However, when corn powder was added up to 30%, no difference existed in the breeding results.

• Journal of Life Science
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• v.30 no.12
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• pp.1054-1062
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• 2020

This study was designed to investigate whether extracts from Oxya chinensis sinuosa Mistshenk (an edible insect considered a grasshopper) could inhibit the activity of carbohydrate digestive enzymes and alleviate postprandial hyperglycemia in diabetic mice. Oxya chinensis sinuosa Mistshenk was extracted with 80% ethanol (OEE) or water (OWE) and then concentrated. The carbohydrate digestive enzyme-inhibiting activity of the resulting extracts was evaluated by examining α-glucosidase and α-amylase. The IC50 values of OEE against α-glucosidase and α-amylase were 0.229 mg/ml and 0.106 mg/ml, respectively. This result indicated that OEE has stronger inhibitory effects than OWE and positive control. The blood glucose levels of the diabetic control mice increased after one meal. However, when OEE (300 mg/kg) was added to starch, this increase in postprandial blood glucose levels was significantly suppressed. The area under the curve also significantly decreased following the administration of OEE, which exhibited no cytotoxicity. These results indicate that OEE is more efficacious than OWE and may be used as a carbohydrate digestive enzyme inhibitor, delay carbohydrate digestion and glucose absorption, and thus alleviate postprandial hyperglycemia caused by dietary carbohydrates.

• The Korean Journal of Mycology
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• v.7 no.1
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• pp.13-73
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• 1979

These studies were conducted to investigate nutrient sources and supplementary materials of synthetic compost media for Agaricus bisporus culture. Investigation were carried out to establish the optimum composition for compost of Agaricus bisporus methods of out-door fermentation and peakheating with rice straw as the main substrate of the media. The incidence and flora of harmful organisms in rice straw compost and their control were also studied. 1. When rice straw was used as the main substrate in synthetic compost as a carbon source. yields were remarkably high. Fermentation was more rapid than that of barley straw or wheat straw, and the total nitrogen content was high in rice straw compost. 2. Since the morphological and physico-chemical nature of Japonica and Indica types of rice straw are greatly dissimilar. there were apparent differences in the process of compost fermentation. Fermentation of Indica type straw proceeded more rapidly with a shortening the compost period, reducing the water supply, and required adding of supplementary materials for producing stable physical conditions. 3. Use of barley straw compost resulted in a smaller crop compared with rice straw. but when a 50%, barley straw and 50% rice straw mixture was used, the yield was almost the same as that using only rice straw. 4. There were extremely high positive correlations between yield of Agaricus bisporus and the total nitrogen, organic nitrogen, amino acids, amides and amino sugar nitrogen content of compost. The mycerial growth and fruit body formation were severely inhibited by ammonium nitrogen. 5. When rice straw was used as the main substrate for compost media, urea was the most suitable source of nitrogen. Poor results were obtained with calcium cyanamide and ammonium sulfate. When urea was applied three separate times, nitrogen loss during composting was decreased and the total nitrogen content of compost was increased. 6. The supplementation of organic nutrient activated compost fermentation and increased yield of Agaricus bisporus. The best sources of organic nutrients were: perilla meal, sesame meal, wheat bran and poultry manure, etc. 7. Soybean meal, tobacco powder and glutamic acid fermentation by-products which were industrial wastes, could be substituted for perilla meal, sesame meal and wheat bran as organic nutrient sources for compost media. B. When gypsum and zeolite were added to rice straw. physical deterioration of compost due to excess moisture and caramelization was observed. The Indica type of straw was more remarkable in increase of yield of Agricus bisporus by addition of supplementing materials than Japonica straw. 9. For preparing rice straw compost, the best mixture was prepared by 10% poultry manure, 5% perilla meal, 1. 2 to 1. 5% urea and 1% gypsum. At spring cropping, it was good to add rice bran to accelerate heat generation of the compost heap. 10. There was significantly high positive correlation (r=0.97) between accumulated temperature and the decomposition degree of compost during outdoor composting. The yield was highest at accumulated temperatures between 900 and $1,000^{\circ}C$. 11. Prolonging the composting period brought about an increase in decomposition degree and total nitrogen content, but a decrease in ammonium nitrogen. In the spring the suitable period of composting was 20 to 25 days. and about 15 days in autumn. For those periods, the degree of decomposition was 19 to 24%. 12. Compactness of wet compost at filling caused an increase in the residual ammonium nitrogen. methane and organic acid during peak heating. There was negative correlation between methane content and yield (r=0.76)and the same was true between volatile organic acid and yield (r=0.73). 13. In compost with a moisture content range between 69 to 80% at filling. the higher the moisture content, the lower the yield (r=0.78). This result was attributed to a reduction in the porosity of compost at filling the beds. The optimum porosity for good fermentation was between 41 and 53%. 14. Peak heating of the compost was essential for the prevention of harmful microorganisms and insect pests. and for the removal of excess ammonia. It was necessary to continue fer mentatiion for four days after peak heating. 15. Ten species of fungi which are harmful or competitive to Agaricus bisporus were identified from the rice compost, including Diehliomyces microsporus, Trichoderma sp. and Stysanus stemoites. The frequency of occurrance was notably high with serious damage to Agaricus bisporus. 16. Diehliomyces microsporus could be controlled by temperature adjustment of the growing room and by fumigating the compost and the house with Basamid and Vapam. Trichoderma was prevented by the use of Bavistin and Benomyl. 17. Four species of nematodes and five species of mites occured in compost during out-door composting. These orgnanisms could be controlled through peakheating compost for 6 hours at $60^{\circ}C$.

• Korean Journal of Microbiology
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• v.54 no.4
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• pp.410-419
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• 2018

It is urgently required to construct safety data on agricultural by-products imported for use as medium materials for domestic mushroom production. However, research on microorganisms is insufficient. This study was conducted to investigate the presence of bacteria that have the possibility of harmful effects on human, plants and mushroom in wheat straw, peatmoss, cottonseed hull, cottonseed meal, and beet pulp imported from Australia, Canada, China, Egypt, Germany. Bacteria were found in the range of $1.35{\times}10^2$ to $8.34{\times}10^6CFU/g$. As a result of 16S rDNA sequence analysis, total of 19 genera and 45 species of bacteria were identified. Bacillus genus was dominant, followed by Paenibacillus genus. At the species level, diverse species was in the order of Firmicute, Proteobacteria and Actinobacteria. Regarding the agricultural by-products, straw and peat moss had more diverse bacteria than other agricultural by-products. Among the indentified bacteria, 6 species of 5 genera (Enterobacter asburiae, Enterobacter ludwigii, Stenotrophomonas maltophilia, Pseudomonas monteilii, Bacillus anthracis, and Cellulosimicrobium funkei) were present as potent harmful bacteria to human. Surprisingly, both the human and plant pathogenic Klebsiella pneumoniae subsp. pneumonia was present. Bacillus altitudinis was present as a plant pathogen. Lysinibacillus sphaericus, an insect pathogen, and Ochrobactrum pseudogrignonense, a mushroom pathogen, were also present. The results of this study confirmed that several kinds of pathogenic bacteria were present in the agricultural by-products for the mushroom cultivation medium imported into Korea. Our work suggests that hygiene inspection and management is urgently needed for imported agricultural by-products to be safely used for mushroom production.