The white-spotted chafer, Protaetia brevitarsis (Coleoptera: Scarabaeidae) was recently listed as a temporal food ingredient by the Korean Ministry of Food and Drug Safety. Traditionally, this beetle has been regarded as a medicine for suppressing live cancer and preventing liver-related disease. Based on these facts, this beetle has been focused as a economically important insects in Korea. Therefore, this beetle is commercially reared and distributed in Korea. As the economic importance is growing, we have investigated to enhance insect rearing conditions for better commercial value. In this study, we compared two food supplements, clay and charcoal, on the larval weight gain for second instar larvae of P. brevitarsis. Clay and charcoal are generally known as a good adsorbent for heavy metals and bio-waste. However, clay and charcoal is not a conventional feed supplements, so its effects were not investigated for insect rearing. The second instar P. brevitarsis larvae were fed fermented sawdust with seven different combinations of cla and/or charcoal, and measured body weight for 17 weeks until pupated. Addition of clay at 2.5 % w/w of the fermented sawdust diet had no negative effect on larval weight gain, and thus may improve the quality of P. brevitarsis as a commercial food.

Antimicrobial peptides (AMPs) can be produced in mealworms. In this work, we integrated Bombyx mori (Bm) AMP, cecropin A to Beauveria bassiana ERL1170 by restriction enzyme-mediated integration method, which was confirmed by RT-PCR and an antibacterial activity assay. For the extracellular secretion of Bm cecropin A protein, the active domain of the cecropin A gene was tailed to the signal sequence of B. bassiana chitinase (Bbs). To exchange Bbs-cecropin A gene with egfp gene in pBARKS1-egfp, Bbs-cecropin A fragment was cut from pGEMBbs-cecropin A using XbaI/blunted and BamHI and ligated with cut pBARKS1-egfp using NcoI/blunted and BamHI, designated as pBARKS1-Bbs-cecropin A. After the transformation, transformants were grown on Czapek’s solution agar containing 600 μg ml-1PPT. Expression of Bm cecropin A was confirmed by RT-PCR. Strong clear zone was observed in the co-culture of the transformant D-6 and Bacillus subtilis on fourth strength Sabouraud dextrose agar 1 day after the culture at 25°C, whereas the wild type had no clear zone. This work suggests that Bm cecropin A can be efficiently produced in this mealworm-based fungal expression platform, thereby increasing the value of mealworms in the animal feed additive industry.

Antimicrobial peptides (AMPs) can be produced in mealworms, currently being used as animal feeds, by the infection of genetically engineered-entomopathogenic fungi. In this work, we integrated Bombyx mori (Bm) AMP, cecropin A to Beauveria bassiana ERL1170 by restriction enzyme-mediated integration method, which was confirmed by RT-PCR and an antibacterial activity assay. For the extracellular secretion of Bm cecropin A protein, the active domain of the cecropin A gene was tailed to the signal sequence of B. bassiana chitinase (Bbs). To exchange Bbs-cecropin A gene with egfp gene in pBARKS1-egfp, Bbs-cecropin A fragment was cut from pGEM-Bbs-cecropin A using XbaI/blunted and BamHI and ligated with cut pBARKS1-egfp using NcoI/blunted and BamHI, designated as pBARKS1-Bbscecropin A. After the transformation, transformants were grown on Czapek’s solution agar containing 600 μg ml-1PPT. Expression of Bm cecropin A was confirmed by RT-PCR. Strong clear zone was observed in the co-culture of the transformant D-6 and Bacillus subtilis on fourth strength Sabouraud dextrose agar 1 day after the culture at 25°C, whereas the wild type had no clear zone. This work suggests that Bm cecropin A can be efficiently produced in this mealworm-based fungal expression platform, thereby increasing the value of mealworms in the animal feed additive industry.

파김치에서 분리한 마늘 내성 유산균인 Lactobacillus plantarum TJ-LP-002 균주의 균체생육과 항균활성에 영향을 미치는 배양조건 및 배지조건을 조사하였다. 선정 유산균의 배양 상등액 내에는 acetic acid, citric acid, lactic acid, tartaric acid와 같은 유기산이 존재하였고, 배양 중에 lactic acid와 acetic acid의 생성이 크게 증가하는 것으로 확인되었다. 단백질분해효소를 비롯한 각종 효소 처리에 의해 항균활성이 소실되지 않아, 선정 유산균이 생산하는 항균활성은 단백질성 물질이 아닌 산 생성에 의한 작용일 것으로 판단되었다. 항생제와 생균제의 병용 가능성을 확인하기 위하여 선정 유산균의 항생제 감수성을 조사한 결과, neomycin sulfate, spectinomycin dihydrochloride, lincomycin hydrochloride에 내성을 나타내었고, streptomycin sulfate에는 감수성을 나타내었으며, ampicillin trihydrate, chloramphenicol, erythromycin, tetracycline hydrochloride, kanamycin sulfate에는 중간 내성을 나타내었다. L. plantarum TJ-LP-002는 배양온도 30oC, 초기 pH 7.0, 24시간의 배양 조건에서 최적의 균체생육과 항균활성을 나타내었으며, 탄소원은 glucose 3%(w/v), 질소원은 yeast extract 3%(w/v) 첨가 시에 균체생육과 항균활성이 높게 나타났다. 무기염류는 manganese sulfate와 ammonium citrate가 항균활성에 많은 영향을 주는 것으로 나타났으며, 각 성분을 단독 첨가하는 것보다 혼합 첨가하는 것이 더 우수한 영향을 나타내는 것으로 확인되었다.

마늘의 항균력에 저항성을 갖는 유산균을 분리하기 위해서 마늘 추출물이 첨가된 배지에서 생육하는 112 균주를 김치, 젓갈, 장아찌류로부터 분리하였다. 이 중에서 14균주에 대해서 내산성 및 내담즙성 그리고, 가축 병원성 세균인 Salmonella choleraesuis, Escherichia coli, Staphylococcus aureus, Shigella flesneri에 대해 항균력을 조사한 결과, 파김치 유래의 P'GW50-2 균주가 가장 우수한 특성을 지니고 있어 생균제로 이용 가능한 균주로 선발하였다. 선발된 균주는 16S rRNA 유전자의 염기서열 분석결과 Lactobacillus plantarum으로 동정되었고 L. plantarum TJ-LP-002으로 명명하였다. L. plantarum TJ-LP-002는 Bacillus cereus, S. aureus, Clostridium perfringens와 같은 Gram 양성균과 Aeromonas hydrophila, E. coli, Pseudomonas, Salmonella, Shigella와 같은 Gram 음성균에 대해서 비교적 넓은 항균활성을 나타내었다.

We investigate the effects of the immune function (HI titer) in broilers fed diets containing Hermetia illucens (H. illucens) peptide extract over a 40-day period. Twenty-four broiler chicks (Arbor Acres, 1 d old) were divided into four groups and fed different diets (control, 0.1%, 0.5%, and 1% H. illucens peptide extract). To evaluate HI titer, all broilers were vaccinated with H9H2 vaccine subcutaneously on the lateral thorax, according to the manufacturer’s recommendations. Similar HI titer was observed with 1% H. illucens peptide extract treatment compared to the control after 40 days (p>0.01). Groups fed 0.5% H. illucens peptide extract demonstrated the most effective immune effects (p<0.01), followed by groups fed 0.1% H. illucens peptide extract. In conclusion, using 0.1% or 0.5% H. illucens peptide extract before or after vaccination improved HI titer immune function in broilers.

The influence of various forms of Houttuynia cordata with fermented red koji as feed additives on the performance of duck livestock was evaluated through a field study. Two hundred and forty ducks (Pekins) aged 0–38 d were used. They were randomly assigned to four treatment groups (0%, 1% H. cordata powder with fermented red koji, 1% H. cordata pelleted with fermented red koji, and 1% H. cordata coated with fermented red koji) with four replicates (15 ducks per replication). Foreconomic evaluation, the data (a total of 240 duck) obtained from each treatment were applied to 10,000 ducks per treatment 38-d after the feeding trial. Overall, the results of economic evaluation were the highest in the treatment with 1% H. cordata coated with fermented red koji, followed by 1% H. cordatapelleted with fermented red koji, 1% H. cordatapowder with fermented red koji, and control. In conclusion, using 1% H. cordatawith fermented red koji as coating and pellet type duck diets might be of economic advantage for sustainable environmental management.

This study made an economic evaluation of duck using Houttuynia cordata (H. cordata) powder as feed additives after 6 weeks. A total of 300 ducks (Pekins) were randomly assigned to one of the three treatments (0%, 0.5% and 1% H. cordata powder), with 5 replicates of 20 ducks each. After 6-week feeding trial, an economic improvement in all the treatments was found in following order: T2 (1% H. cordata powder) > T1 (0.5% H. cordata powder) > control. The results suggested that the addition of H. cordata powder to duck diets provided significantly greater economic benefits, indicating sustainable environmental management of the duck industry.