• BMB Reports
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• v.44 no.6
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• pp.387-392
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• 2011

To investigate the molecular scavenging capabilities of the larvae of Hermetia illucens, two serine proteases (SPs) were cloned and characterized. Multiple sequence alignments and phylogenetic tree analysis of the deduced amino acid sequences of Hi-SP1 and Hi-SP2 were suggested that Hi-SP1 may be a chymotrypsin- and Hi-SP2 may be a trypsin-like protease. Hi-SP1 and Hi-SP2 3-D homology models revealed that a catalytic triad, three disulfide bonds, and a substrate-binding pocket were highly conserved, as would be expected of a SP. E. coli expressed Hi-SP1 and Hi-SP2 showed chymotrypsin or trypsin activities, respectively. Hi-SP2 mRNAs were consistently expressed during larval development. In contrast, the expression of Hi-SP1 mRNA fluctuated between feeding and molting stages and disappeared at the pupal stages. These expression pattern differences suggest that Hi-SP1 may be a larval specific chymotrypsin-like protease involved with food digestion, while Hi-SP2 may be a trypsin-like protease with diverse functions at different stages.

• International Journal of Industrial Entomology and Biomaterials
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• v.35 no.2
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• pp.100-105
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• 2017

Under natural conditions, black soldier fly, Hermetia illucens (L.) (Diptera: Stratiomyidae), colonizes in warm temperate regions, and is active in Korea from May through October. Information on black soldier fly rearing, which is affected by seasonal factors in Korea, is limited. Oviposition by black soldier flies is dependent on light intensity and wavelength. Therefore, continuous mass rearing of this fly requires determination of optimal artificial conditions of illumination. In this study, we compared the number of eggs laid under an artificial light source (750 watt HPL lamp) versus nature sunlight. Our results showed that compared to oviposition under natural sunlight, the use of one or two lamps for 7 hours, resulted in only 43 and 76%, of the total number of eggs laid under natural sunlight, respectively. We also investigated the hatchability of oviposited eggs under artificial illumination and under natural sunlight. The hatching rate under the former was much significantly lower than under the latter. Further detailed research is required to develop methods for successful mass rearing of black soldier fly throughout the year by means of an indoor system.

• Journal of Life Science
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• v.32 no.8
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• pp.601-610
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• 2022

P. tenebrifer (PT) belongs to the Diptera order and Stratiomyidae family. Recently, insect industry have been focused as food, animal feed and environmental advantages. γ-aminobutyric acid (GABA) and melatonin have been associated with regulating sleep and depression. GABA is the primary inhibitory neurotransmitter and is synthesized via biotransformation of monosodium glutamate (MSG) to GABA by lactic acid bacteria. In this study, we first used a GABA-enhanced PT extract, wherein GABA was enhanced by feeding MSG to PT. The underlying mechanisms preventing stress and insomnia were investigated in a corticosterone (CORT)-induced endoplasmic reticulum (ER) stress and chronic restraint stress (CRS)-exposed mouse model, as well as in pentobarbital (45 mg/kg)-induced sleep behaviors in mice. In the present study, the GABA peak was detected in high-performance liquid chromatography-evaporative light scattering detector (HPLC-ELSD) analysis and showed in Ptecticus tenebrifer water extract (PTW) but not in non-PTW extract. The results showed that PTW and Ptecticus tenebrifer with 70% ethanol extract (PTE) exerted neuroprotective effects by protecting against CORT-induced downregulation of phosphorylated extracellular signal-regulated kinase 1/2 (ERK1/2) and cAMP-response element binding protein (CREB) expression. In addition, PTW (300 mg/kg) significantly reduced CORT levels in CRS-exposed mice. Furthermore, PTW (100 and 300 mg/kg) significantly reduced sleep latency and increased total sleep duration in pentobarbital (45 mg/kg)-induced sleeping behaviors, which was related to serum melatonin levels. In conclusion, our results suggest that PTW exerts anti-stress and sleep-enhancing effects by regulating serum CORT and melatonin levels.

• Korean journal of applied entomology
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• v.54 no.4
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• pp.409-417
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• 2015

This study aimed to summarize the characteristics of visitor experience for different market segments based on insect experience orientation in order to develop Ptecticus tenebrifer (Diptera: Stratiomyidae [Walker]) experience programs using local resources in the insect industrial market. A total of 325 effective samples were collected, and the attributes of insect experience orientation were connected to education, emotion, society, and ego. The survey respondents were students and parents of school-age children. Cluster analysis showed that the respondents were classified into two or three groups that were all found to be high in the prediction validity and discriminant analysis. Based on this result, the respondents were properly subdivided into three clusters for final analysis. Those three groups were: the passive group, the moderate group, and the active-orientation group. As a group aiming for various insect experiences, the active-orientation group consisted of parents whose children range in age from either 5 to 9 or from 10 to 14. This group was willing to spend 7 ~ 8,000 won on each experience program, and they preferred emotional experience programs. The passive and moderate orientation groups were most interested in having an educational experience. In order to increase people's interest in experience programs, education-oriented programs should be developed and promotional marketing should be reinforced. The results and implications of this study may be useful for the development of insect experience programs that can meet various visitor experience orientations as basic data that can contribute to the vitalization of the 6th industrialization plan for the insect industry.