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To clarify the anti-obesity effect of Allomyrina dichotoma larvae (ADL), we previously reported that ADL block adipocyte differentiation on 3T3-L1 cell lines through downregulation of transcription factors, such as peroxisome proliferator-activated receptor-γ (PPARG) and CCAAT/enhancer binding protein-α (CEBPA). In this study, we tested whether ADL prevent obesity in mice fed a high-fat diet (HFD) and further investigated the mechanism underlying the effects of ADL. All mice were maintained on a normal-fat diet (NFD) for 1 week and then assigned to one of five treatment groups: (1) NFD; (2) HFD; (3) HFD and 100 mg·kg−1·day−1 ADL; (4) HFD and 3000 mg·kg−1·day−1ADL; or (5) HFD and 3000 mg·kg−1·day−1 yerba mate (Ilex paraguariensis, positive control). ADL and yerba mate were administered orally daily. Mice were fed experimental diets and body weight was monitored weekly for 6 weeks. Our results indicated that ADL reduced body weight gain, organ weight and adipose tissue volume in a dose-dependent manner. Body weight gain was approximately 22.4% lower compared to mice fed only HFD, but the difference did not reach the level of statistical significance. Real-time polymerase chain reaction (PCR) analysis revealed that gene expression levels of PPARG, CEBPA and lipoprotein lipase (LPL) in the epididymal fat tissue of HFD-fed mice receiving 3000 mg·kg−1·day−1 ADL were reduced by 12.4-, 25.7-, and 12.3-fold, respectively, compared to mice fed HFD only. Moreover, mice administered ADL had lower serum levels of triglycerides and leptin than HFD-fed mice that did not receive ADL. Taken together our results suggest that ADL and its constituent bioactive compounds hold potential for the treatment and prevention of obesity.

Beetles Protaetia brevitarsis seulensis Kolbe (Coleoptera: Cetoniidae) and Allomyrina dichotoma Linn. (Coleoptera: Scarabaeidae) are widely used in traditional medicine, and the number of insect-rearing farms is increasing in South Korea. The purpose of this study was to establish a multiplex PCR-based assay for rapid simultaneous detection of multiple pathogens causing insect diseases. Six insect parasites such as fungi Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Cordycipitaceae) and Metarhizium anisopliae (Metschn.) Sorokin (Hypocreales: Clavicipitaceae), bacteria Bacillus thuringiensis Berliner (Bacillales: Bacillaceae), Pseudomonas aeruginosa Migula (Pseudomonadales: Pseudomonadaceae), and Serratia marcescens Bizio (Enterobacteriales: Enterobacteriaceae), and Oryctes rhinoceros nudivirus were chosen based on the severity and incidence rate of insect diseases in South Korea. Pathogen-specific primers were designed and successfully applied for simultaneous detection of multiple infectious agents in farm-bred insects P. b. seulensis and A. dichotoma using multiplex PCR and high resolution capillary electrophoresis. Our results indicate that multiplex PCR is an effective and time-saving method for simultaneous detection of multiple infections in insects, and the QIAxcel capillary electrophoresis system is useful for quantitative evaluation of the individual impact of each infectious agent on the severity of insect disease. The approach designed in this study can be utilized for rapid and accurate diagnostics of infection in insect farms.© 2015 The Korean Society of Sericultural Sciences Int. J. Indust. Entomol. 30(2), 64-74 (2015) IntroductionFollowing a global trend of using natural products from insects, the Korean government has been encouraging the development of insect resources for environmental and dietary purposes, traditional medicine, and as pets (Kim et al., 2013 Vol. 30, No. (1), pp. 64-74 (2015) Pseudomonas aeruginosa is reported as a virulent bacterial pathogen not only for insects but also for mammals (Jander et al., 2000), where it causes infection of the respiratory tract, especially in cystic fibrosis patients (Spiker et al., 2004). Similar to Pseudomonas aeruginosa, Serratia marcescens is known as an opportunistic bacterium (El-Aasar et al., 2013); it is also used to control apple maggot fly population and as a source of insecticidal agents such as toxin luxA (Hejazi and Falkiner, 1997; Lauzon et al., 2003). Oryctes rhinoceros virus Rhabdionvirus oryctes Hüger was first discovered in oil palms in Malaysia 40 years ago and is currently used for the control of rhinoceros beetle population in Malaysia (Huger, 2005;Ramle et al., 2005).We have identified this virus in an A. dichotoma-breeding farm in 2014 in Korea (Lee, 2015).Extensive large-scale insect breeding has resulted in frequent occurrence of insect infection due to multiple pathogens. Here, we developed a multiplex PCR-based approach that allowed simultaneous detection of six insect pathogens using specific primer se...

To investigate whether Serratia marcescens (Enterobacteriales: Enterobacteriaceae) isolated from Protaetia brevitarsis seulensis(Coleoptera: Cetoniidae) acts as an opportunistic bacterium in peroral infection, the primary entomopathogenic bacteria Bacillus thuringiensis (Bacillales: Bacillaceae) and Paenibacillus popilliae (Eubacteriales: Bacillaceae) were added to sawdust to perform a bioassay experiment. We found that peroral infection caused by S. marcescens could be fatal beyond a concentration of 4 × 10 8 pfu/mL in 2 nd stage P. b. seulensis larvae and at 6 × 10 8 pfu/mL in 3 rd stage P. b. seulensis larvae. In particular, mortality resulting from a combination of P. popilliae and S. marcescens was markedly increased in 2 nd stage P. b. seulensis larvae. Therefore, we confirmed that mortality was increased when S. marcescens was infected together with other entomopathogenic bacteria, and that peroral infection itself can be fatal beyond certain concentrations.