• 한국식품영양학회지
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• 제7권2호
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• pp.151-158
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• 1994

This study was carried out to clear up the cause of low-acid producing phenomenon occurred In non-fat dry milk during liquid-yoghurt fermentation by Lactobacillus case, and to present its improving methods. All samples of non-fat dry milks which were low in TCA-soluble peptides showed low-acid production, but those high in TCA-soluble peptides showed high-acid production. The addition of trypsin-hydrolysate of Na-caseinate to non-fat dry milk showed some improving effect on acid production but that of papain-hydrolysate did not show any improving effect and that of bacterical neutral protease-hydrolysate showed some inhibitory effect. The improving effects on growth and acid production of lactic acid bacteria were more prominent when the trypsin-hydrolysate of Na-caseinate was added. to such fermenting system in which the levels of TCA-soluble peptides and the proteolytic ability of starter bacteria were abnormally low. The liquid-yoghurt made with non-hydrolysed Na-caseinate and defective non-fat dry milk showed precipitate occurrence but that with trypsin-hydrolysate of Na-caseinate and defective non-fat dry milk did not make any precipitate during storage as with normal non-fat dry milk.

• Preventive Nutrition and Food Science
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• 제20권4호
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• pp.276-283
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• 2015

Hydrocolloids have many applications in foods including their use in dysphagia diets. We aimed to evaluate whether hydrocolloids in foods affect the digestibility of starch and protein, and their effects on antioxidant capacity. The thickening hydrocolloids: locust bean gum and carboxymethyl cellulose, and the gel-forming agents: agar agar, konjacglucomannan, and Hot & Soft Plus were blended with corn starch and soy protein, skim milk, or grape juice and were examined for their in vitro-digestability by comparing the reducing sugar and trichloroacetic acid (TCA)-soluble peptide, for antioxidant capacity by total polyphenol contents and the 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity. The hydrocolloids resulted in a decrease in starch digestibility with the gel-forming agents. Hydrocolloids diminished TCA-soluble peptides in skim milk compared to soy protein with the exception of locust bean gum and decreased free radical scavenging capacities and total phenolic contents in grape juice. Our findings may provide evidence for the use of hydrocolloids for people at risk of nutritional deficiencies such as dysphagia patients.

• Animal Bioscience
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• 제35권12호
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• pp.1892-1903
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• 2022

Objective: A series of experiment were conducted to evaluate the effects of replacing a part of soybean meal (SBM) at 6% of broiler diets with fermented soybean meal (FSBM) obtained by single or two-stage fermentation by measuring growth performance, antioxidant activity in the jejunum and distal intestinal microflora. Methods: Soybean meal samples were prepared by single-stage fermentation using Bacillus velezensis (Bv) (FSBM_B), or Lactobacillus spp. (as commercial control) (FSBM_L). Additional SBM sample was prepared by two-stage fermentation using Bv and subsequently using Lactobacillus brevis ATCC 367 (Lb) (FSBM_B+L). Enzyme activity, chemical composition, trichloroethanoic acid-nitrogen solubility index (TCA-NSI) and antioxidant activity were measured. Then, in an in vivo study, 320 Ross308 broilers were divided into four groups with ad libitum supply of feed and water. Four groups were fed either a corn-soybean meal diet (SBM), or one of fermented SBM diets (FSBM_B+L, FSBM_B, and FSBM_L). Growth, serum characteristics, microflora, and the mRNA expression of selected genes were measured. Results: Compared to SBM, FSBM_B+L contained lower galacto-oligosaccharide, allergic protein, and trypsin inhibitor, and higher TCA-NSI by about three times (p<0.05). Reducing power and 1,1-diphenyl-2-picrylhydrazyl free radical scavenging ability correlated positively with the TCA-NSI content in FSBM. Growth performances were not significantly different among four groups. In jejunum of 35-day-old broilers, partial replacement of SBM by FSBM_B+L increased the activity of superoxide dismutase and catalase (CAT), and the FSBM_B group had the highest catalase activity (p<0.05). Partial replacement of SBM by FSBM increased relative mRNA expressions of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and peptide transporter 1 (PepT1) (p<0.05); however, FSBM_B+L increased CAT mRNA level to 5 times of the control (p<0.05). Conclusion: Using Bv- and Lb-processed SBM through two-stage fermentation to partially replace 6% of diets will improve the gut's antioxidant activity under commercial breeding in broilers.

• Journal of Dairy Science and Biotechnology
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• 제30권1호
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• pp.45-53
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• 2012

본 연구는 모유를 섭취하고 있는 생후 7일째 신생아의 분변으로부터 L. acidophilus를 분리 및 동정하고, 이들의 생리적 특성을 규명하여 상업적 이용가능성을 검토하고자 실시하였다. 이를 위해 pH 5.5에서 생장하는 lactobacilli 43균주를 분리하고, 그 중 pH 2.5에서 생존율이 약 80% 이상이고, homo 젖산 발효를 하는 lactobacilli 14균주를 1차 분리하였으며, 분리된 lactobacilli 14균주의 생화학적 특성, 당 이용성 및 균체 지방산 조성의 확인을 통해 동정된 L. acidophilus 9균주(NB 201~NB 209)를 시험 균주로 선발하였다. 내산성 실험 결과, 시험 균주를 pH 2.5에서 2시간 배양하였을 때 모든 시험 균주가 80% 이상의 생존율을 나타내었으며, L. acidophilus NB 204는 pH 2.0에서도 71%의 생존율을 보여 내산성이 높은 것으로 나타났다. 담즙산 내성은 73%의 생존율을 보인 L. acidophilus NB 206을 제외한 8균주가 bile extract가 1%의 농도로 첨가된 배지에서 생존율이 85% 이상으로 담즙산 내성이 매우 우수한 것으로 확인되었다. 또한 시험 균주 모두가 단백질 분해 활력이 있는 것으로 확인되었으며, yeast extract 0.1% 첨가한 것과 비교하여 0.2% 첨가 시 또는 24시간 배양과 비교하여 48시간 배양 시 TCA 가용성 펩타이드 및 유리 아미노산 생성량이 높았으며, 특히 L. acidophilus NB 204와 NB 209가 높은 생성량을 보였다(또는, yeast extract의 첨가량 및 배양시간이 증가함에 따라 TCA 가용성 펩타이드 및 유리 아미노산 생성량이 증가하였으며, 특히 L. acidophilus NB 204와 NB 209가 높은 생성량을 보였다). 시험 균주들의 ${\beta}$-galactosidase 활성은 1.97~2.45 unit/mL의 범위를 나타내었다.

• 한국식품과학회지
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• 제28권1호
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• pp.99-104
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• 1996

탄수화물을 갖고 있지 않은 caseinomacropeptide (CMP)를 감성유청분말로부터 12% TCA법에 의해 분리한 결과 100 g의 감성유청분말로 부터 2.7 g을 얻을 수 있었다. 분리된 CMP는 전기영동과 아미노산 조성을 분석한 결과 매우 순도가 높은 CMP로 나타나 12% TCA침전법은 감성유청분말로 부터 CMP를 분리하는 효과적인 방법임을 알 수 있었다. 트립신을 pore glass beads에 carbodiimide (EDC) 방법으로 amide결합에 의해 고정화시켰으며 고정화된 트립신의 양은 1 g glass beads당 20 mg이었다. 수용성 트립신에 의한 CMP 가수분해는 24시간이 지나면 거의 완료되었으며 고정화 트립신은 24시간이 지난 후에도 가수분해가 진행되고 있었다. 가수분해물을 Bio-Gel P4 column에 의해 분획한 후 혈소판 응집 저해작용을 측정한 결과 고정화 트립신에 의해 24시간 가수분해시킨 CMP 분해물이 가장 높은 혈소판 응집 억제능을 보였다.