• Korean journal of applied entomology
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• v.56 no.3
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• pp.301-308
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• 2017

Locusts, Locusta migratoria (Orthoptera: Acrididae) are periodical unpredictable agricultural pests worldwide and cause serious damage to crop production; however, little consideration has been given to the management of this pest. Herein, we constructed a locust-pathogenic fungal library and confirmed that some fungi could be used as resources for locust management. First, the entomopathogenic fungi were collected from sampled soils using a Tenebrio molitor-based baiting system. For the locust assay, a locust colony was obtained from the National Institute of Agricultural Science and Technology. A total of 34 entomopathogenic fungal granules, which were produced by solid cultures, were placed in the plastic insect-rearing boxes (2 g/box) and nymphs of locust were contained in the box. In 3-7 days, mycosis was observed on the membranous cuticles of the head, abdomen, and legs of locusts. In particular, Metarhizium anisopliae, M. lepidiotae, and Clonostachys rogersoniana exhibited high virulence against the locust. Given that the 34 isolates could be used in field applications, their conidial production and stability (thermotolerance) were further characterized. In the thermotolerance assay, Paecilomyces and Purpureocillium isolates had higher thermotolerance than the other isolates. Most of the fungal isolates produced ca. >$1{\times}10^8conidia/g$ on millet grain medium. In a greenhouse trial, the granular application of M. anisopliae isolate on the soil surface resulted in 85.7% control efficacy. This work suggests that entomopathogenic fungi in a granular form can be effectively used to control the migratory locust.

• Korean Journal of Food Science and Technology
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• v.51 no.5
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• pp.480-485
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• 2019

The present study was conducted to compare antioxidant capacities of protein hydrolysates from four different edible insects (Protaetia brevitarsis larvae, Allomyrina dichotoma larvae, Gryllus bimaculatus imago, and Tenebrio molitor larvae) which have recently been registered as food varieties in Korea. Protein hydrolysates were prepared from each insect using enzymatic hydrolysis using alcalase, and were then separated into a fraction containing ${\leq}3kDa$. According to $RC_{50}$ values and trolox equivalent antioxidant capacity results obtained from five different antioxidant analyses, the Gryllus bimaculatus (GB) hydrolysate showed relatively high levels of antioxidant capacity and, in particular, the GB hydrolysate showed considerably strong antioxidant activities in 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and in ferric reducing antioxidant power (FRAP) assays. The GB hydrolysate also showed the strongest inhibitory effect on peroxidation of linoleic acid, and its rate of inhibition at $100{\mu}g/mL$ on day 3 of treatment was 60.26%. These results suggest that protein hydrolysates from edible insects including GB represent potential sources of natural antioxidants.