• 생명과학회지
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• 제31권1호
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• pp.83-89
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• 2021

개불 라이소자임(Uu-ilys)은 개불(Urechis unicinctus)로부터 정제된 무척추형 라이소자임으로 병원균에 대한 방어에 주요하게 작용하는 선천성 면역 물질이며, 비효소적 항균 활성을 가지고 있어 항균 활성을 지닌 유도체의 개발 가능성을 가지고 있다. 본 논문은 개불 라이소자임에서 유래된 항균 활성을 가지는 유도체의 디자인과 생산을 기술하고 있다. 여러 항균성 펩타이드(antimicrobial peptide, AMP) 데이터베이스에서 제공하는 항균성 펩타이드 예측 도구를 사용하여 개불 라이소자임에서 항균 활성을 가지는 부위를 예측하였다. 개불 라이소자임 C-말단의 절편이 항균 활성을 나타낼 것으로 예측되었으며, 이 펩타이드는 C-말단 절편, Uu-ilys-CF라 명명하였다. Uu-ilys-CF은 이형 발현 시스템인 TrxA-Uu-ilys-CF 퓨전 단백질을 사용하여 생산하였다. 만들어진 퓨전 단백질은 브롬화시안을 사용하여 메티오닌 잔기를 절단하였으며, 절단된 Uu-ilys-CF은 고성능액체크로마토그래피와 역상 컬럼인 CapCell-Pak C18을 사용하여 분리되었다. Uu-ilys-CF의 항균 활성을 조사하기 위해서 여러 균주(그람양성균 4개, 그람음성균7개, 진균 1개)를 사용하였다. Uu-ilys-CF의 항균 활성은 살모넬라에서 가장 높은 반응을 보였다. 비록 Uu-ilys-CF는 진균에 활성을 나타내지 않았지만, 사용한 균주들에서 넓은 범위의 항균 활성을 나타내었다.

• 생명과학회지
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• 제32권6호
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• pp.438-446
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• 2022

꽃은 특유한 모양, 색, 향, 맛으로 인한 시각적, 후각적 관능성이 우수하다. 최근에는 식용 꽃을 건조한 후 열수로 우려내는 침출차가 사회적 관심을 받고 있으며, 식용꽃을 이용한 기능성 식의약품 소재 개발도 진행되고 있다. 그러나 현재까지 건조꽃차의 유해 미생물, 중금속 및 잔류농약에 대한 위해성 평가는 거의 이루어진 바 없으며 농산물과 달리 건조꽃차에 대한 안전성 규격도 마련되어 있지 않다. 본 연구에서는 시판 건조꽃차의 유해 미생물, 중금속 및 잔류농약 오염도를 평가하였다. 먼저 유해 미생물 오염도 평가에서 23종 꽃차 시료 모두에서 대장균군 및 리스테리아균은 검출되지 않았다. 그러나 갈화, 캐모마일꽃, 아카시아꽃, 진달래꽃, 달맞이꽃, 유채꽃, 벚꽃의 경우 3.24~3.85 Log CFU/g의 일반세균이 검출되었으며, 황색포도상구균도 23종 꽃차 중 11종에서 검출되었다. 살모넬라균 역시 23종 꽃차 중에서 8종에서 검출되어 시판 꽃차의 유해 미생물 관리가 필요함을 확인하였다. 한편 대부분의 꽃차에서는 Pb, Cd, Co, Cr, Cu, Ni 및 As 유해 중금속은 검출되지 않았으나, 원추리꽃차에서만 0.08 ppm의 Pb가 검출되었다. 따라서 시판 꽃차에서 별도의 중금속 위해는 없을 것으로 판단된다. 건조꽃차의 경우 일부 꽃에서 잔류농약이 검출되었으나 극미량(0.01~0.08 ppm)으로 유해성은 없으리라 판단되었으며, 다만 국화꽃차에서 검출된 chlorpyrifos (0.215 ppm)의 경우 잠재적 위해 가능성이 인정되었다. 본 연구 결과는 건조꽃차의 잔류농약기준 설정이 필요하며, 식용꽃차의 안전성 확보를 위해 식용꽃차와 농약 사용이 허용되는 관상용 꽃의 엄격한 재배 구분이 필요하며, 꽃의 수확, 가공, 유통 단계에서 미생물적 오염 방지 노력도 필요함을 제시하고 있다.

• 한국축산식품학회지
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• 제42권1호
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• pp.153-174
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• 2022

This trial was conducted to evaluate the effect of overwrap, vacuum, and modified atmosphere packaging (MAP) on poultry breast fillets' microbiological, biochemical shelf life and sensory attributes. The fillets were divided into 4 groups, and each of the treatments was replicated 3 times with 60 breast fillets. The first group was a control group with overwrap packaging; the second group was vacuum packed (VP); the third and fourth groups were MAP-1: 0% O₂, 40% CO₂, 60% N₂, and MAP-2: 20% O₂, 40% CO₂, 40% N₂. The microbiological and biochemical analyses were performed for the total viable count, coliform count, Pseudomonas count, Salmonella count, total volatile basic nitrogen (TVB-N), pH, cooking loss, color, lipid oxidation, tenderness, and sensory analysis. The data were analysed through two-way ANOVA by Minitab (Minitab 17.3.1). Meat treated with understudy MAP compositions and vacuum packaging reduced total viable count, Pseudomonas count, and total coliform count than control (p<0.05). TVB-N remained below the recommended limit throughout storage except aerobic packaging (p<0.05). Cooking loss (%) was lowered and showed non-significant results (p>0.05) between vacuum packaging and both MAP concentrations. The meat stored in MAP-2 was characterised by higher (p<0.05) visual scores. Whilst MAP-1 showed higher (p<0.05) L^* values and overall acceptability. Sample packaged under aerobic packaging showed significant (p<0.05) results for b^* and thiobarbituric acid reactive substances (TBARS). Meat stored in aerobic packaging showed higher (p<0.05) shear force values. The outcome of this trial may help to promote the application of understudy MAP compositions and rapid detection of microbes by biochemical analysis under local conditions.

• 한국식품과학회지
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• 제54권2호
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• pp.209-217
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• 2022

본 연구에서는 모유 유래 유산균 E. faecalis BMSE-HMP005의 다제내성 균주에 대한 항균효과 및 probiotics로써 잠재적인 가능성을 확인하였다. E. faecalis BMSE-HMP005는 다제내성 균주 20주(Enterococcus spp., Staphylococcus spp., Escherichia spp., Pseudomonas spp., Salmonella spp., Klebsiella spp., Enterobacter spp.)에서 모두 MBC가 확인되어 다제내성 균주에 대한 우수한 항균효과를 입증하였다. 또한 RP-HPLC를 이용하여 배양액 내 bacteriocin을 확인하였으며, 이에 대한 분획은 gram 양성 및 gram 음성균주에서 모두 항균력이 나타나, E. faecalis BMSE-HMP005가 생산하는 bacteriocin의 광범위한 항균 스펙트럼을 입증하였다. E. faecalis BMSE-HMP005는 발암 화합물을 유발하는 β-glucuronidase에 대한 활성과 용혈성은 나타나지 않아 안전한 것으로 판단된다. E. faecalis BMSE-HMP005는 vancomycin에 대해서는 내성을 보이나, kanamycin (>0.058), ampicillin (>0.002), erythromycin (>0.002)은 EFSA 기준의 허용범위보다 낮은 MIC가 확인되었다. 또한 인공위액(pH 2.0) 및 인공 담즙산(0.3% bile acid) 조건에서 각각 98.67%, 95.70%의 생존율을 보였다. 이와 같은 결과는 본 연구에서 분리한 모유 유래 유산균 E. faecalis BMSE-HMP005가 다제내성 균주에 대한 우수한 항균활성을 갖는 probiotics로써 잠재적인 가능성을 보여준다. 따라서 건강기능식품의 기준 및 규격에 제시된 바와 같이 Enterococcus spp.는 항생제 내성 및 독성 유전자가 없는 경우에 한하여 probiotics로 사용이 가능한 고시하고 있어 E. faecalis BMSE-HMP005의 안전성에 대한 추가적인 검증이 필요할 것으로 판단된다.

• 한국수산과학회지
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• 제54권6호
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• pp.896-903
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• 2021

For the safety assessment of microbiological and chemical hazards in raw short-neck clam Ruditapes philippinarum distributed in the Yeongnam and Honam areas during the spring season, the contamination levels of total viable bacteria, coliforms, Escherichia coli, and nine pathogenic bacteria (Staphylococcus aureus, Salmonella spp., Vibrio parahaemolyticus, Clostridium perfringens, Listeria monocytogenes, enterohemorrhagic Escherichia coli, Yersinia enterocolitica, Bacillus cereus, Campylobacter jejuni) as microbiological hazards, and heavy metals (lead, cadmium, total mercury), benzopyrene, shellfish poison (paralytic, diarrhetic, amnesic), and radioactivity (¹³¹I, ¹³⁴Cs+¹³⁷Cs) were also analyzed in 15 samples based on the methods of the Korean Food Code. The average contamination levels of total viable bacteria were 3.11 (1.40-4.49) log CFU/g, and coliforms were detected in 5 out of 15 samples (1.18-1.85 log CFU/g). E. coli and S. aureus were not detected in all samples. Furthermore, the presence of 8 pathogens were not detected in all samples. The average contamination levels of lead, cadmium, and total mercury were 0.155 (0.079-0.264), 0.160 (0.040-0.287), and 0.017 (0.008-0.026) mg/kg, respectively. Benzo(a)pyrene, shellfish poison, and radioactivity were not detected in all samples. The results of this study suggest that the safety against all microbiological and chemical hazard factors in raw short-neck clams distributed in markets has been assured.

• 한국수산과학회지
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• 제54권6호
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• pp.904-911
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• 2021

For the safety assessment of microbiological and chemical hazards in dried sea mustard, fifteen samples of dried sea mustards Undaria pinnatifida were purchased from the supermarkets distributed throughout Korea. The contamination levels of total viable bacteria, coliforms, Escherichia coli, and nine pathogenic bacteria [Staphylococcus aureus, Salmonella spp., Listeria monocytogenes, Bacillus cereus, Vibrio spp., Clostridium perfringens, Enterohemorrhagic Escherichia coli (EHEC), Yersinia enterocolitica and Campylobacter jejuni/coli] were quantitatively or qualitatively assessed. Also, the heavy metals (lead, cadmium, total mercury, and inorganic arsenic), and radioactivity (¹³¹I, ¹³⁴CS+¹³⁷CS) were quantitatively assessed. This microbial and chemical analysis was performed using standard methods in Korean food code. The total viable bacteria ranged from 4.3×10² (5.0×10-1.5×10³) CFU/g. Coliforms and E. coli were not detected in all samples (ND, <1 log₁₀ CFU/g). All nine pathogenic bacteria were qualitatively detected as negative. The contamination levels of lead, cadmium, total mercury, and inorganic arsenic were 0.036 (0.015-0.051), 0.117 (0.088-0.156), 0.030 (0.017-0.048), and 0.058 (0.056-0.064) mg/kg, respectively. Radioactivity was also not detected in any sample. The microbial contamination levels determined in the current study may be potentially used as basis for performing microbial risk assessments of dried sea mustards.

• Animal Bioscience
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• 제35권11호
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• pp.1752-1759
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• 2022

Objective: Effects of direct-fed Enterococcus faecium plus bacteriophages (EF-BP) were investigated as potential substitutes for pharmacological ZnO for weanling pigs. Methods: Dietary treatments were supplementations to a basal diet with none (NC), 3,000-ppm ZnO (PC), 1×10¹⁰ colony-forming units of E. faecium plus 1×10⁸ plaque-forming units (PFU) of anti-Salmonella typhimurium bacteriophages (ST) or 1×10⁶ PFU of each of anti-enterotoxigenic Escherichia coli K88 (F4)-, K99 (F5)-, and F18-type bacteriophages (EC) per kg diet. In Exp 1, twenty-eight 21-day-old crossbred weanling pigs were individually fed one of the experimental diets for 14 days and euthanized for histological examination on intestinal mucosal morphology. In Exp 2, 128 crossbred weanling pigs aged 24 days were group-fed the same experimental diets in 16 pens of 8 piglets on a farm with a high incidence of post-weaning diarrhea. Results: None of the diarrheal score or fecal consistency score (FCS), average daily gain (ADG), gain: feed ratio, structural variables of the intestinal villus, and goblet cell density, differed between the EF-BP (ST+EC) and NC groups, between EF-BP and PC, or between ST and EC, with the exception of greater gain: feed for EF-BP than for PC (p<0.05) during days 7 to 14 (Exp 1). In Exp 2, ADG was less for EF-BP vs PC during days 0 to 7 and greater for EF-BP vs NC during days 7 to 14. FCS peaked on day 7 and declined by day 14. Moreover, FCS was less for EF-BP vs NC, did not differ between EF-BP and PC, and tended to be greater for ST vs EC (p = 0.099). Collectively, EF-BP was comparable to or slightly less effective than PC in alleviating diarrhea and growth check of the weanling pigs, with ST almost as effective as PC, when they were group-fed. Conclusion: The E. faecium-bacteriophage recipe, especially E. faecium-anti-S. typhimurium, is promising as a potential substitute for pharmacological ZnO.

• 농업과학연구
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• 제49권3호
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• pp.539-545
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• 2022

The aim of this study was to evaluate the effect of beekeeping by-products added to drinking water on the growth performance and intestinal and fecal microflora of Institute of Cancer Research (ICR) mice. A total of 72 five-week-old ICR mice with an initial body weight (BW) of 24.57 ± 0.60 g were used in a two-week experiment. The four treatment groups were as follows; 1) CON, normal distilled water; 2) T1, CON with 0.7% beehive extract; 3) T2, CON with 0.7% propolis (PRO); and 4) T3, CON with 0.7% royal jelly (RJ). Each treatment consisted of 6 replicate cages with 3 mice per cage. At 0 - 1 week, T3 showed a significantly higher (p < 0.05) body weight gain (BWG) and feed efficiency (G : F) than that of CON. Compared with CON, T2 showed a significantly higher (p < 0.05) BWG and feed intake at 1 - 2 weeks. During the entire period, T2 and T3 showed a significantly higher (p < 0.05) BWG and G : F compared to CON. The amount of Salmonella and Lactobacillus in the large intestine was significantly decreased and increased (p < 0.05) in T2 and T3, respectively, compared to CON. The amount of Escherichia coli in the fecal matter was significantly reduced (p < 0.05) compared to CON in all treatment groups to which beekeeping by-products were added. In conclusion, the addition of PRO or RJ to the drinking water of ICR mice had a positive effect on the growth performance and the intestinal and fecal microflora.

• 생명과학회지
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• 제32권12호
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• pp.997-1004
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• 2022

비지박을 포함하는 먹이원을 급이한 흰점박이꽃무지 유충의 영양학적 우수성과 안전성을 검증하고자 비지박 함유 먹이원과 참나무 발효톱밥만으로 사육한 유충의 영양성분과 유해물질을 비교분석하였다. 조단백질 함량은 비지박 함유 먹이원을 급이한 유충(SCC)에서 50.0%로 참나무 발효톱밥으로 사육한 유충(FOS) 44.7%보다 1.1배 많았다. 다량무기질 중 가장 많은 함량을 나타낸 칼륨은 SCC (3169.6 mg/100 g)에서 FOS(1245.9 mg/100 g)보다 2.5배 더 많았다. 미량무기질 중 아연은 SCC (103.0 mg/100 g)에서 FOS (8.2 mg/100 g)보다 12.6배 높은 함량을 나타냈다. 유해물질 분석 결과, SCC와 FOS에서 납, 카드뮴, 비소 모두 식용곤충 중금속 기준에 적합하였고, 병원성 미생물인 대장균과 살모넬라균은 모두 불검출되었다. 위의 연구 결과에 따르면, 비지박을 급이한 흰점박이꽃무지 유충은 다양한 영양성분을 포함하고 있으며, 안전성 또한 검증되었으므로 식용으로 활용하기에 적합할 것으로 판단된다.

• Journal of Animal Science and Technology
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• 제64권1호
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• pp.70-83
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• 2022

A set of studies was performed to determine the influence of dietary ZnO concentration and source during two phases (days 0 to 14 and days 15 to 28). Experiment 1: 168 weaned piglets were allocated to four treatment groups in six replicates. The treatments included a basal diet without ZnO supplementation (control), 2,500 mg ZnO/kg (In2500), 500 mg nano-ZnO/kg (N500), and 150 mg nano-ZnO/kg (N150). Experiment 2: 168 weaned piglets were divided into three treatment groups with eight replicates. The treatments included control, In2500, N300, and 150 mg nano-ZnO/kg (N150). An in vitro trial showed that the growth of Listeria monocytogenes, Escherichia coli, and Salmonella typhimurium was inhibited when exposed to 300 and 500 ppm of ZnO after 24 h of incubation. In experiment 1, the average daily gain (ADG) by the pigs was improved in the N500 and IN2500 treatment groups. Colonization of coliforms and Clostridium spp. significantly decreased in the pigs fed the N500 and IN2500 diets in phase 1. The total plasma antioxidant capacity was greater in the IN2500 and N500 treatment groups than in the control. Superoxide dismutase (SOD) activity was greater in pigs fed the IN2500 (phase 1) or the IN2500 and N500 (phase 2) diets than in the control and N150 treatment group. In experiment 2, pigs in the N300 treatment group showed a higher ADG and lower fecal score colonization of coliforms and Clostridium spp. compared with those in the N150 treatment group. In conclusion, nano-ZnO at a dose of 300 ppm showed the same growth as the pharmacological dose of Zn. This provides an option to the pharmacological dose.