• Animal Bioscience
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• 제35권4호
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• pp.556-566
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• 2022

Objective: This study aimed to determine the appropriate supplementation level of lactic acid bacteria (LAB; Lactobacillus plantarum and Bacillus clausii), yeast (Saccharomyces cariocanus and Wickerhamomyces anomalus) for degrading free gossypol and glucosinolate in the fermented total mixed ration (TMR) containing cottonseed meal (CSM) or rapeseed meal (RSM), to improve the utilization efficiency of these protein sources. Methods: For LAB, L. plantarum or B. clausii was inoculated at 1.0×10⁸, 1.0×10⁹, 1.0×10¹⁰, and 1.0×10¹¹ colony-forming unit (CFU)/kg dry matter (DM), respectively. For yeast, S. cariocanus or W. anomalus was inoculated at 5×10⁶, 5×10⁷, 5×10⁸, and 5×10⁹ CFU/kg DM, respectively. The TMR had 50% moisture and was incubated at 30℃ for 48 h. After fermentation, the chemical compositions, and the contents of free gossypol and glucosinolate were determined. Results: The results showed that the concentration of free gossypol content was reduced (p<0.05), while that of the crude protein content was increased (p<0.05) in the TMR containing CSM inoculated by B. clausii (1×10⁹ CFU/kg DM) or S. cariocanus (5×10⁹ CFU/kg DM). Similarly, the content of glucosinolate was lowered (p<0.05) and the crude protein content was increased (p<0.05) in TMR containing RSM inoculated with B. clausii (1×10¹⁰ CFU/kg DM) or S. cariocanus (5×10⁹ CFU/g DM). Conclusion: This study confirmed that inclusion of B. clausii with 1.0×10⁹ or 1.0×10¹⁰ CFU/kg DM, or S. cariocanus (5×10⁹ CFU/kg DM) to TMR containing CSM/RSM improved the nutritional value and decreased the contents of anti-nutritional factors.

• 한국동물위생학회지
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• 제45권2호
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• pp.117-124
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• 2022

In the event of an outbreak of a livestock epidemic, it has been considered that the existing burial-centered carcass disposal method should be improved ecofriendly for prevention of leachate and odors from burial basically in regard of pathogen inactivation. Therefore, the aim of this study is whether it was possible to treat the carcass of cattle and chickens using the chemical carcass treatment method. It was conducted to establish detailed treatment standards for the chemical treatment method of cattle and chicken carcasses based on the results of the proof of the absence of infectious diseases in cattle chickens. After inoculating cattle carcass with 10 pathogens (foot and mouth disease virus, bovine viral diarrhea virus, Mycobacterium bovis, Mycobacterium avium subsp. Paratuberculosis, Brucella abortus, Bacillus anthracis, Clostridium chauvoei, Clostridium perfringens, Escherichia coli, and Salmonella Typhimurium) and chicken carcasses with low pathogenic avian influenza virus, Clostridium perfringens type C, E. coli and Salmonella Typhimurium, these were treated at 90℃ for 5 hours in a potassium hydroxide liquid solution corresponding to 15% of the body weight. This method liquefies all cadaveric components and inactivates all inoculated pathogens by PCR and culture. Based on these results, it was possible to prove that chemical treatment of cattle and chicken carcasses is effective in killing pathogens and is a safe method without the risk of disease transmission. The chemical treatment method of livestock carcasses can be suggested as an alternative to the current domestic burial-centered livestock carcass treatment method, preventing environmental pollution, and contributing to public health.

• 한국수산과학회지
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• 제56권2호
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• pp.182-187
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• 2023

Fifteen samples of dried laver Pyropia tenera were collected from markets and processing plants in Korea for an assessment of their microbial and chemical hazards, in accordance with the Korean food code. The contamination levels of total viable bacteria, coliforms, Escherichia coli, and nine other pathogenic bacteria (Staphylococcus aureus, Salmonella spp., Vibrio parahaemolyticus, Clostridium perfringens, Listeria monocytogenes, Enterohemorrhagic Escherichia coli, Yersinia enterocolitica, Bacillus cereus, and Campylobacter jejuni) were evaluated The concentrations of heavy metals (lead, cadmium, total mercury, and total arsenic) and radioactive isotopes (¹³¹I, and ¹³⁴Cs+¹³⁷Cs) in the laver samples were also determined. The total viable count of bacteria was 2.62±0.80 (1.48-4.45) CFU/g. The contamination levels of lead, cadmium, total mercury, and total arsenic were 0.024±0.005 (0.018-0.035), 0.090±0.038 (0.041-0.146), 0.008±0.005 (0.003-0.018) and 1.315±0.372 (0.814-1.930) mg/kg, respectively. All samples tested negative for significant levels of radioactivity, the nine pathogenic bacteria, coliforms, and E. coli (<1.00 CFU/g). We assume that ensuring the microbiological and chemical safety of dried laver can increase the demand for its exportation. The present study may serve as a basis for microbiological and chemical hazard assessment of dried lavers.

• 한국미생물·생명공학회지
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• 제50권3호
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• pp.347-353
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• 2022

본 연구는 기존의 probiotics로서의 안전성을 입증한 B. cabrialesii sp. K1과 prebiotics 중 inulin 3%와 혼합하여 synbiotics로서의 넙치의 성장과 비특이적 면역 반응 및 세균성 감염에 따른 폐사에 미치는 영향을 검토하였다. 8주 동안 단일 프로바이오틱스 B. cabrialesii sp. K1과 inulin 3% 를 혼합한 신바이오틱스를 급이 한 결과 성장에서는 유의적인 차이를 보이지 않았다. 혈액학적 검사의 경우 AST, total protein 및 cholesterol에서 유의적인 차이를 보였고 ALT와 glucose는 유의적인 차이가 없었다. 비특이적 면역반응에서는 유산균 첨가 또는 주사제로 인한 라이소자임 활성이 유익 하다고 알려져 있으나 본 연구에서는 8주동안 대조구와 비교시 유의적 차이가 없었다. 또한 B. cabrialesii K1의 경우 단일 프로바이오틱스구보다 신바이오틱스구가 대조구에 비해 NBT 활성이 증가된 것을 확인할 수 있었다. 다음 넙치의 사이토카인 발현을 확인한 결과 B. cabrialesii sp. K1를 단일 (probiotics구)로 사용했을 경우 대조구와 비교 시 비장에서 유의적으로 낮게 발현되었으나 synbiotics구의 경우 비장에서 발현이 유의하게 증가되었다. 그러나 나머지 간과 장, 신장에서는 세 개의 그룹 간의 유의적 차이를 나타내지 않았다. 마지막으로 2주동안의 인위 감염을 검토한 결과 대조구는 E. tarda 95%, S. parauberis 85%, S. iniae 85%로 각 각의 폐사율을 나타냈다. Probiotics구는 E. tarda 85%, S. parauberis 80%, S. iniae 80%의 폐사율을 보였고, synbiotics 구는 E. tarda 80%, S. parauberis 80%, S. iniae 85%로 각 각 나타났다.

• 한국식품영양학회지
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• 제36권1호
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• pp.33-41
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• 2023

To increase antioxidant and antibacterial activities of seasoned soy sauce, five kinds of oriental medicinal plant(Scutellaria baicalensis (P1), Coptis japonica makino (P2), Citriunshius pericarpium (P3), Zizyphi spinosi semen (P4), Crataegus pinnatifida(P5)) and four kinds of medicinal mushrooms(Inonotus obliquus (M1), Hericium erinaceus (M2), Phellinus linteus (M3), Lentinula edodes(M4)) were added to seasoned soy sauce. Soluble solid content, pH, salinity, total polyphenol & flavonoid contents were determined. DPPH & ABTS radical scavenging activities, SOD-like activity, and antibacterial activity were analyzed. Experimental sauces showed decreased pH but significant increases of soluble solid content and salinity. Total polyphenol content was 12.76 ㎍ GAE/g in the control. However, M1 and P1 sauce had significantly higher polyphenol contents at 352.14 and 528.25 ㎍ GAE/g, respectively. Total flavonoids content also showed the same pattern. DPPH free radical scavenging activity was the lowest in the control at 15.75%. It was the highest at 81.80% in M1 and 68.88% in P1. ABTS free radical scavenging activity and SOD-like activity showed the same tendencies. They were higher in the experimental groups than in the control. As for the antibacterial activity analyzed by the paper-disc method, the activity increased the most in P1 and P2. In particular, P2 had the strongest antibacterial activity. Its activity against different microorganisms was in the order of Staphylococcus aureus > Bacillus cereus > Escherichia coli > Salmonella typhimurium. In conclusion, these new sauces show increased antioxidative and antioxidant activities. Therefore, they are expected to be used in various ways as a functional soy sauce.

• Fisheries and Aquatic Sciences
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• 제25권11호
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• pp.579-586
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• 2022

Research on the potential biological activity of red alga Symphyocladia spp. has been limited to Symphyocladia latiuscula, which is widely used as a food ingredient in Korea. Here, we examined the biological activity of another species, Symphyocladia linearis, which is found in Korea and was reported as a new species in 2013. The aim of this study was to evaluate the antioxidant, anti-inflammatory, and antibacterial properties of a 70% ethanol extract of S. linearis. Antioxidant activity, which was evaluated using radical scavenging assays, revealed half maximal inhibitory concentration values for 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) and 2,2'-azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) of 34.57 and 11.70 ㎍/mL algal extract, respectively. Anti-inflammatory activity of the S. linearis ethanolic extract was evaluated using RAW 264.7 cells by measuring the inhibition of lipopolysaccharide-induced nitric oxide (NO) and prostaglandin E₂ (PGE₂) production. The potential cytotoxicity of NO and PGE₂ was first examined, confirming no toxicity at concentrations ranging from 10-100 ㎍/mL. NO production was inhibited 61.1% and 78.0% at 50 and 100 ㎍/mL S. linearis extract, respectively; and PGE₂ production was inhibited 69.1%, 83.2%, and 94.8% at 25, 50, and 100 ㎍/mL S. linearis extract, respectively. Thus, the S. linearis extract showed very strong efficacy against PGE₂ production. The cellular production of reactive oxygen species, measured using 2',7'-dichlorofluorescin diacetate fluorescence, was inhibited 48.8% by the addition of 100 ㎍/mL S. linearis extract. Antibacterial activity was evaluated using the disc diffusion method and minimum inhibitory concentration (MIC). S. linearis was effective only against gram-positive bacteria, exhibiting antibacterial activity against Staphylococcus aureus with a MIC of 256 ㎍/mL extract and against Bacillus cereus with a MIC of 1,024 ㎍/mL extract. Based on these results, we infer that a 70% ethanolic extract of S. linearis possesses strong anti-inflammatory properties, and therefore has the potential to be used in the prevention and treatment of inflammatory and immune diseases.

• Journal of Microbiology and Biotechnology
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• 제33권1호
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• pp.51-60
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• 2023

The foodborne illness is the important public health concerns, and the livestock feces are known to be one of the major reservoirs of foodborne pathogens. Also, it was reported that 45.5% of foodborne illness outbreaks have been associated with the animal products contaminated with the livestock feces. In addition, it has been known that the persistence of a pathogens depends on many potential virulent factors including the various virulent genes. Therefore, the first step to understanding the public health risk of livestock feces is to identify and describe microbial communities and potential virulent genes that contribute to bacterial pathogenicity. We used the whole metagenome shotgun sequencing to evaluate the prevalence of foodborne pathogens and to characterize the virulence associated genes in pig and chicken feces. Our data showed that the relative abundance of potential foodborne pathogens, such as Bacillus cereus was higher in chickens than pigs at the species level while the relative abundance of foodborne pathogens including Campylobacter coli was only detected in pigs. Also, the microbial functional characteristics of livestock feces revealed that the gene families related to "Biofilm formation and quorum sensing" were highly enriched in pigs than chicken. Moreover, the variety of gene families associated with "Resistance to antibiotics and toxic compounds" were detected in both animals. These results will help us to prepare the scientific action plans to improve awareness and understanding of the public health risks of livestock feces.

• Journal of Microbiology and Biotechnology
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• 제33권2호
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• pp.219-227
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• 2023

Lettuce is one of the most consumed vegetables worldwide. However, it has potential risks associated with pathogenic bacterial contamination because it is usually consumed raw. In this study, we investigated the changes in the bacterial community on lettuce (Lactuca sativa L.) in Chungcheong-do, South Korea, and the prevalence of foodborne pathogens on lettuce in different seasons using 16S rRNA gene-based sequencing. Our data revealed that the Shannon diversity index showed the same tendency in term of the number of OTUs, with the index being greatest for summer samples in comparison to other seasons. Moreover, the microbial communities were significantly different between the four seasons. The relative abundance of Actinobacteriota varied according to the season. Family Micrococcaceae was most dominant in all samples except summer, and Rhizobiaceae was predominant in the microbiome of the summer sample. At the genus level, the relative abundance of Bacillus was greatest in spring samples, whereas Pseudomonas was greatest in winter samples. Potential pathogens, such as Staphylococcus and Clostridium, were detected with low relative abundance in all lettuce samples. We also performed metagenome shotgun sequencing analysis on the selected summer and winter samples, which were expected to be contaminated with foodborne pathogens, to support 16S rRNA gene-based sequencing dataset. Moreover, we could detect seasonal biomarkers and microbial association networks of microbiota on lettuce samples. Our results suggest that seasonal characteristics of lettuce microbial communities, which include diverse potential pathogens, can be used as basic data for food safety management to predict and prevent future outbreaks.

• 한국자원식물학회지
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• 제36권4호
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• pp.264-274
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• 2023

본 연구는 제주지역에서 대량 발생하고 있는 생태계 교란 외래식물을 기능성 바이오소재로서의 이용 가능성을 확인하기 위한 연구의 일환으로서, 5종 외래식물체의 70% 에탄올 추출물을 대상으로 항산화, 항염증 및 항균 효과와 유효성분을 조사하였다. 외래식물의 총 폴리페놀 및 플라보노이드 함량은 애기수영 > 서양금혼초 ≥ 가시상추 > 환삼덩굴 ≥ 왕도깨비가지 순서로 나타났다. 외래식물의 DPPH 및 ABTS 라디칼 소거능 역시 애기수영에서 가장 높았으며, 항산화 효과는 식물 추출물의 총 폴리페놀 및 플라보노이드 함량과 연관된 것으로 확인되었다. LPS로 자극시킨 RAW 264.7 세포에서 외래식물체 에탄올 추출물(100 ㎍ SE/mL)의 NO 및 PGE₂ 생성 억제 효과는 각각 약 20~60%와 10~70%로 나타났고, 애기수영 및 환삼덩굴이 다른 3종에 비해 우수한 것으로 나타났다. 4종의 식중독 유발 미생물 및 5종의 구강 미생물을 대상으로 식물 추출물의 항균 효과를 조사한 결과, 환삼덩굴, 애기수영 및 왕도깨비가지의 에탄올 추출물은 B. subtilis, E. coli, V. parahaemolyticus 및 V. vulnificus 4종 식중독균 모두에 대해 강한 항균 활성을 보였다. 구강충치 유발 미생물인 E. faecalis, L. casei, R. dentocariosa, S. epidermidis, S. mutans에 대한 항균 효과는 환삼덩굴 추출물이 효과적이었으며, 항균 활성에 관여하는 주 유효성분은 pentadecylic acid, palmitic acid, clionasterol 등인 것으로 예측되었다. 이상의 결과는 생태계 교란 외래식물, 특히 애기수영 및 환삼덩굴의 기능성을 갖는 유효성분 분리 및 이용화 연구에 중요한 기초자료가 될 것이며, 항산화, 항염증 및 항균제 개발을 위한 바이오소재 발굴 등에도 중요한 정보를 제공할 수 있을 것으로 사료된다.

• 한국식품위생안전성학회지
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• 제38권1호
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• pp.26-30
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• 2023

본 연구에서는 자외선 살균기의 미생물 오염 상태를 분석하고 위생관리 방안을 제시하고자 하였다. 본 실험에 사용된 자외선 살균기는 전라남도 소재 일부 보육시설 98곳의 자외선 살균기를 대상으로 하였다. 일반세균 및 대장균군은 식품공전 미생물 시험법에 따라 실험하였다. 일반 세균은 98개 보육시설 중 67개소(68.4%), 대장균군은 5개 소(5.1%)에서 검출되었다. 식중독세균 실험 결과 Salmonella spp. 등 6종의 식중독세균은 검출되지 않았지만 B. cereus 는 98개 보육시설 중 1개소(2.8%)에서 검출되었다. 자외선 램프 교체 주기에 따른 일반세균 검출율은 3개월 이내가 6개 보육시설 중 3개소(50%), 3개월 이상 6개월 이내가 5개 보육시설 중 3개소(60%), 6개월 이상이 87개 보육시설 중 61개소(70.1%)로 나타났다. 대장균군 검출율은 6개월 이내에는 검출되지 않았으나 6개월 이상이 87개 보육시설 중 5개소(5.7%)로 나타났다. 자외선 살균기의 미생물 오염도는 램프 교체 주기가 길어질수록 미생물 오염도가 높게 나타났다. 또한 자외선 램프 교체 주기가 6개월 이상인 87개 보육시설 중 23개소(26.4%)의 자외선 살균기 반사판에는 물기가 있고 청소상태가 불량한 것으로 나타났다. 이러한 결과를 종합해 볼 때 보육시설에서 사용 중인 자외선 살균기의 위생관리를 위해 주기적인 청소 와 자외선 램프 교체가 필요한 것으로 판단된다. 또한 보육시설 급식담당자들에게 자외선 살균기 청결과 램프 교체에 대한 지속적인 교육이 필요할 것으로 판단되었다.