• Korean Journal of Agricultural Science
• /
• v.49 no.3
• /
• pp.511-520
• /
• 2022

Insect-resistant transgenic rice (Bt-T) expresses a toxic protein (mcry1Ac1) derived from the soil bacterium Bacillus thuringiensis found in the rice cultivar Dongjin with an insecticidal property against rice leaf roller (Cnaphalocrocis medinalis). In this study, to investigate the impact of Bt-T on non-target organisms, the feed and oviposition preferences and biological parameters of brown planthopper (Nilaparvata lugens Stål) were comparatively analyzed in four rice cultivars: Dongjin (parent variety), Ilmi (reference cultivar), Chinnong (brown planthopper resistant cultivar) and Bt-T. In the Bt-T and Dongjin cultivars, the feed preferences were 32.4 ± 8.3 and 34.1 ± 6.8%, and the oviposition preferences were 32.5 ± 5.1 and 30.0 ± 5.3% respectively, and there was no statistical significance between these rices. Additionally, in the Bt-T and Dongjin cultivars, the total lifespans from egg to adult were 39.5 ± 6.9 and 40.0 ± 5.8 days, and the weights of adult females were 1.78 ± 0.14 and 1.72 ± 0.16 mg, respectively. Therefore, there was no statistical difference in the biological parameters between these two varieties. Overall, the results indicate that the insect-resistant transgenic rice (Bt-T) did not negatively affect the reproduction and life cycle of brown planthopper, a non-target organism.

• Journal of Life Science
• /
• v.29 no.9
• /
• pp.996-1001
• /
• 2019

Edible insects are reported to be rich in protein, minerals and vitamins, and much attention has been paid to them as a future food source. In Korea, they were massively reared and sold. In order to enhance the market value of edible insects for industrialized mass production, it is important to develop the safe and nutritious feed sources for rearing them are needed. In this study, a chlorella-free control feed (Exp1) and six experimental feeds supplemented with 0.5~2.0% liquid or powder types of chlorella were formulated. Protaetia brevitarsis and Allomyrina dichotoma, registered as food ingredients in Korea, were fed with the designed feeds and parameters of growth including larval survivorship, larval body weight, and larval period were analyzed. When chlorella added, larval survivorship was increased 2~13%(p>0.05) and 9~22%(p<0.05) in each beetle compared to the control. Interestingly, the larval period of chlorella powder-added groups was shortened by 24 days (Exp3, p<0.05) in P. brevitarsis and 19 days (Exp4, p<0.01) in A. dichotoma. Meanwhile, some parameters, crude protein, crude fiber, copper, zinc, potassium, magnesium, and phosphorous, in chlorella-added groups of P. brevitarsis were also higher than the control group. Therefore, chlorella could promote the larval growth performance of these two beetles and be used as a feed additive in rearing them.

• Korean journal of applied entomology
• /
• v.58 no.3
• /
• pp.219-224
• /
• 2019

The super mealworm, Zophobas morio, is mainly used as food for pets, fish, reptiles, amphibians, birds, and as snacks. An experiment was conducted to investigate the effects of temperature, supplementary feeding, and spawning interval on super mealworm rearing. To efficiently rear this species, the insects were bred at a temperature of $27^{\circ}C$ or higher and reached a weight of over 0.6 g at 80 days after hatching. Supplementary feed (with high protein content: 10% of soybean meal and 10% of fish meal) enabled larvae to reach a weight of over 0.7 g at 80 days after hatching. Mass rearing of super mealworm requires increase in egg production (i.e., high yield) and uniformity of larvae. Adults were transferred to spawning bases every 5, 10, or 15 days (three treatments), which resulted in a total of 7,256, 5,439, 2,060 hatched larvae, respectively. It is possible to obtain more than 7,000 larvae by transferring the egg-laying frame to the spawning base at intervals of 5 days and with nine spawning operations; this procedure generates larvae weighing over 0.68 g each.

• Biotechnology and Bioprocess Engineering:BBE
• /
• v.2 no.2
• /
• pp.113-116
• /
• 1997

The hydrogel process is a different form of ultrafiltration and has been used to separate biological molecules. In this study, the gel pore size was predicted by pulse NMR technique and neural network using a database obtained from gel filtration chromatography and diffusion experiment. Recombinant alkaline phosphatase expressed in insect cells was concentratred 1.5 times by hydrogel ultrafiltration by swelling at 2$0^{\circ}C$ and collapsing at 35$^{\circ}C$ at 53-65% separation efficiency and 78-83% enzyme recovery. Wild and recombinant Autographa californica unclear polyhedrosis viruses (AcNPV) were also concentrated 1.4 and 1.6 times of the feed solution at 48.5 and 60.0% separation efficiency, respectively Hydrogel ultrafiltration appears to be an attractive alternative for the concentration of AcNPV and recombinant proteins from insect cells.

• Korean journal of applied entomology
• /
• v.61 no.1
• /
• pp.221-227
• /
• 2022

In accordance with Article 6 of the 「Insect Industry Promotion and Support Act」, the National Institute of Agricultural Sciences conducted a fact-finding investigation in the insect industry for related workers in 2020. Most commonly, insect industry workers were involved in production (98.5%), the male ratio was high (80.4%), while those in their 50s comprised 36.4% of the workers. As for the uses of industrial insects, 66.5% was for food and medicine, 12.7% for feed, and 20.7% as pets. The most commonly produced industrial insect species by use were the white-spotted flower chafer (69.6%), Protaetia brevitarsis seulensis (Kolbe), for food and medicine; crickets (31.2%) for feed; and the rhinoceros beetle (45.6%), Allomyrina dichotoma (Linnaeus), as pets. Powder was the most common product form at 68.5%, and live insects constituted 40.9%. Insect farms with an annual income accounted for 77.3%, of which 65.4% had annual sales of less than 20 million won. Market acquisition was rated by most insect industry workers (84.0%) as the primary challenge. In conclusion, although the number of people employed in the insect industry is increasing annually, the number of young insect farmers (20s to 40s) is decreasing. The production of industrial insects was limited to a few species, and more than half of insect farms have very low incomes. Furthermore, insect farms have the greatest difficulty in market acquisition, necessitating the development of utilization technology to promote the consumption of industrial insects.

• Journal of Sericultural and Entomological Science
• /
• v.53 no.2
• /
• pp.78-81
• /
• 2015

This study aimed to determine a feed withdrawal duration time of Gryllus bimaculatus (Gb), for removal of intestinal feces. Finally, this species of cricket has been temporarily approved for use as a human food source in Korea. To commercialize Gb as an edible insect, we attempted to prevent the proliferation of micro-organisms and improve taste of Gb by removing intestinal feces of live crickets. Our study showed that weak crickets were damaged in 2 days after feed withdrawal in farm. The microscope findings also revealed that feces of strong crickets' intestine almost disappeared at 1 day after feed withdrawal and instead, some of arms and legs of weak crickets were observed in the former's intestine. The results suggest that 1 day is deemed to be an adequate time for feed withdrawal, when it usually takes 1 day to deliver live crickets from the farm to a destination.

• Food Science and Industry
• /
• v.55 no.2
• /
• pp.188-202
• /
• 2022

In the insect industry, as the scope of application of insects is expanded from pet insects and natural enemies to feed, edible and medicinal insects, the demand for quality control of insect raw materials is increasing, and interest in securing the safety of insect products is increasing. In the process of expanding the industrial scale, controlling the temperature and humidity and air quality in the insect breeding room and preventing the spread of pathogens and other pollutants are important success factors. It requires a controlled environment under the operating system. European commercial insect breeding facilities have attracted considerable investor interest, and insect companies are building large-scale production facilities, which became possible after the EU approved the use of insect protein as feedstock for fish farming in July 2017. Other fields, such as food and medicine, have also accelerated the application of cutting-edge technology. In the future, the global insect industry will purchase eggs or small larvae from suppliers and a system that focuses on the larval fattening, i.e., production raw material, until the insects mature, and a system that handles the entire production process from egg laying, harvesting, and initial pre-treatment of larvae., increasingly subdivided into large-scale production systems that cover all stages of insect larvae production and further processing steps such as milling, fat removal and protein or fat fractionation. In Korea, research and development of insect smart factory farms using artificial intelligence and ICT is accelerating, so insects can be used as carbon-free materials in secondary industries such as natural plastics or natural molding materials as well as existing feed and food. A Korean-style customized breeding system for shortening the breeding period or enhancing functionality is expected to be developed soon.

• Journal of Microbiology and Biotechnology
• /
• v.19 no.12
• /
• pp.1628-1634
• /
• 2009

Small heat shock proteins (sHSPs) function as molecular chaperones that protect cells against environmental stresses. In the present study, the genes of hsp17.6 and hsp17.7, cytosolic class I sHSPs, were cloned from a tropical plant, Ageratina adenophorum. Their C-terminal domains were highly conserved with those of sHSPs from other plants, indicating the importance of the C-terminal domains for the structure and activity of sHSPs. The recombinant HSP17.6 and HSP17.7 were applied to determine their chaperone function. In vitro, HSP17.6 and HSP17.7 actively participated in the refolding of the model substrate citrate synthase (CS) and effectively prevented the thermal aggregation of CS at $45^{\circ}C$ and the irreversible inactivation of CS at $38^{\circ}C$ at stoichiometric levels. The prior presence of HSP17.7 was assumed to suppress the thermal aggregation of the model substrate CS. Therefore, this report confirms the chaperone activity of HSP17.6 and HSP17.7 and their potential as a protectant for active proteins.

• International Journal of Industrial Entomology and Biomaterials
• /
• v.39 no.2
• /
• pp.54-59
• /
• 2019

Yellow mealworms (Tenebrio molitor Linnaeus) are very promising insects for the food and feed industry. Because mealworms are in the spotlight as an alternative protein source in the future, it is necessary to develop efficient rearing techniques for mass production. To evaluate the effects of brewer's yeast (BY) on the growth of mealworms, Tenebrio molitor Linnaeus, the mealworms were fed with wheat bran (WB) diets containing different levels of BY (0, 10, 30, 50, and 70%). Larval survival, larval weight, development time, pupal weight and eclosion rate were monitored for 12 weeks. The results showed that mealworms fed on the diets containing 30% and 50% of BY have significantly higher weight gain, specific growth rate and daily weight gain, and lower larval duration than fed the control diet (100% WB) and other BY diets (10% and 70% BY). Larval survival on the diets containing 30% and 50% of BY was higher than on control diet. Pupal weight and eclosion rate were not significantly different among all diets. In conclusion, we suggest feeding the diet containing 30% of brewer's yeast with wheat bran in order to increase the production of mealworms.

• Korean Journal of Veterinary Research
• /
• v.61 no.4
• /
• pp.36.1-36.8
• /
• 2021

The objective of this study was to evaluate the beneficial effects of the short-term application of insect-based diet in canine allergic dermatitis. Total 19 atopic dogs with concurrent cutaneous adverse food reactions were enrolled and classified into 3 groups. The treatment group (n = 7) was fed insect-based diet, the positive control group (n = 6) was fed salmon-based diet, and the negative control group (n = 6) was fed commercial or homemade diet for 12 weeks. The degree of skin lesions was evaluated based on canine atopic dermatitis extent and severity index (CADESI-4). Additionally, transepidermal water loss (TEWL) and pruritus visual analog scale were evaluated. All indices were evaluated every 4 weeks after the initial administration of hypoallergenic diets. In the treatment group, significant decrease in the CADESI-4 score was observed at 8 weeks compared to the baseline score (p = 0.031). There were significant differences in the CADESI-4 score between the groups at 8 weeks (p = 0.008), 12 weeks (p = 0.012), and TEWL at 12 weeks (p = 0.022). This preliminary result demonstrates the potential hypoallergenicity of an insect-based diet through features that diminish cutaneous lesions and skin barrier dysfunction.