• International Journal of Industrial Entomology and Biomaterials
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• 제48권2호
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• pp.67-77
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• 2024

This study aims to assess the efficacies of exogenous enzymes, derived from invertebrate gut-associated microbes, as feed additives, in reducing volatile organic compound (VOC) emissions using an in vitro pig intestine continuous fermentation system. An in vitro continuous fermentation model was used to simulate a comparable bionic digestion system by co-reacting feed, enzymatic additives (arazyme, mannanase, and xylanase, derived from the gut bacteria of Nephila clavata, Eisenia fetida, and Moechotypa diphysis, respectively), and gastrointestinal microbes, followed by an analysis of their correlations. A significant correlation was observed between exogenous enzyme supplementation and reduced VOC emissions in the fecal phase of continuous fermentation (p < 0.05). The concentration of VOCs decreased by 3.75 and 2.75 ppm in the treatment group following arazyme and multi-enzyme supplementation, respectively, compared to that in the control group (7.83 ppm). In addition, supplementation with arazyme and multiple enzymes significantly affected the microbial composition of each fermentation phase (p < 0.05). In particular, Lactiplantibacillus pentosus and Pediococcus pentosaceus, which changed in abundance according to arazyme or multi-enzyme supplementation, exhibited a positive relationship with VOC emissions. These results suggest that exogenous enzymes derived from invertebrate gut-associated bacteria can be efficiently applied as feed additives, leading to a reduction in VOC emissions.

• Journal of Microbiology and Biotechnology
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• 제16권11호
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• pp.1753-1759
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• 2006

Paenibacillus sp. HY-8 isolated from the digestive tracts of the longicorn beetle, Moechotypa diphysis, produced an extracellular endoxylanase with a molecular weight of 20 kDa estimated by SDS-PAGE. The xylanase was purified to near electrophoretic homogeneity from the culture supernatant after ammonium sulfate precipitation, gel filtration, and ionexchange chromatography. The purified xylanase exhibited the highest activities at pH 6.0 and $50^{\circ}C$. The $K_m\;and\;V_{max}$ values were 7.2 mg/ml and 16.3 U/mg, respectively, for birchwood xylan as the substrate. Nucleotide sequence of the PCR-cloned gene was determined to have the open reading frame encoding a polypeptide of 212 amino acids. The N-terminal amino acid sequence and the nucleotide sequence analyses predicted that the precursor xylanase contained a signal peptide composed of 28 amino acids and a catalytically active 19.9-kDa peptide fragment. The deduced amino acid sequence shared extensive similarity with those of the glycoside hydrolase family 11 of xylanases from other bacteria. The predicted amino acid sequence contained two glutamate residues, previously identified as essential and conserved for active sites in other xylanases of the glycoside hydrolase family 11.

• Journal of Microbiology
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• 제45권5호
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• pp.394-401
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• 2007

In this study, bacterial communities within the guts of several longicorn beetles were investigated by a culture-dependent method. A total of 142 bacterial strains were isolated from nine species of longicorn beetle, including adults and larvae. A comparison of their partial 16S rRNA gene sequences showed that most of the bacteria constituting the gut communities can typically be found in soil, plants and the intestines of animals, and approximately 10% were proposed as unreported. Phylogenetic analysis demonstrated that the bacterial species comprised 7 phyla, and approximately half were Gammaproteobacteria. Actinobacteria were the second most populous group (19%), followed by Firmicutes (13%) and Alphaproteobacteria (11%). Betaproteobacteria, Flavobacteria, and Acidobacteria were minor constituents. The taxonomic compositions of the isolates were variable according to the species of longicorn beetle. Particularly, an abundance of Actinobacteria existed in Moechotypa diphysis and Mesosa hirsute, which eat broadleaf trees; however, no Actinobacteria were isolated from Corymbia rubra and Monochamus alternatus, which are needle-leaf eaters. Considerable proportions of xylanase and pectinase producing bacteria in the guts of the longicorn beetles implied that the bacteria may play an important role in the digestion of woody diets. Actinobacteria and Gammaproteobacteria were the dominant xylanase producers in the guts of the beetles.

• 생명과학회지
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• 제18권3호
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• pp.363-368
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• 2008

국내의 자생곤충 76종으로부터 다양한 용매를 이용하여 304종의 추출물을 조제한 후, 이들의 항혈전 활성을 평가하였다. 먼저 트롬빈 저해활성 평가 결과, 방아깨비, 왕잠자리, 비단노린재 및 끝검은메뚜기의 DMSO 추출물 4종, 알락수염노린재, 가시길쭉바구미, 잔날개여치, 털두꺼비하늘소, 송장벌레과 유충 및 등빨간거위벌레의 물 추출물 6종에서 우수한 활성을 확인하였다. 선정된 10종을 대상으로 aPTT 측정결과 비단노린재, 방아깨비 및 잔날개여치 추출물에서 미약한 증가가 나타났으나, 전반적으로 혈전 생성 저해의 유의적인 변화는 인정되지 않아, 이들 추출물들은 트롬빈을 직접 저해하는 것으로 추측되었다. 한편 항트롬빈 활성이 우수한 10종 추출물 중에서 방아깨비, 가시길쭉바구미, 알락수염노린재 및 송장벌레과 유충 추출물에서는 우수한 DPPH 소거능을 나타내어 이들의 약용 곤충자원으로의 개발 가능성을 확인하였다.