• The Korean Journal of Food And Nutrition
• /
• v.9 no.2
• /
• pp.167-175
• /
• 1996

This studies were conducted to select optimal enzyme that produced hydrolysate from soybean, and to evaluated functionality of hydrolysate. Soybean powder was suspended with water and hydrolyzed by seven commercial proteases. Hydrolysate produced with protease from Bacillus subtilis showed the highest inhibition effect on the activity of angiotension converting enzyme(ACE), and the condition of enzymatic hydrolysis was 5cA substrate concentration, 0. l% enzyme concentration, 4 hour hydrolysis time. Under above optimum condition, soybean was hydrolyzed with protease from Bacillus subtilis yielding a DH (degree of hydrolysis) of about 49%. Hyrophobicity of hydrolysate was not correlated with the inhibition effect on ACE activity. The functionality of hydrolysate was significantly influenced by pH. Solubility of hydrolysate at alkali solution was greater than that at acidic solution.

• Journal of Microbiology and Biotechnology
• /
• v.25 no.1
• /
• pp.26-32
• /
• 2015

Four types of straw, namely, soybean, wheat, corn, and rice, were investigated for use in lactic acid production. These straws were mainly composed of cellulose, hemicellulose, and lignin. After pretreatment with ammonia, the cellulose content increased, whereas the hemicellulose and lignin contents decreased. Analytical results also showed that the liquid enzymatic hydrolysates were primarily composed of glucose, xylose, and cellobiose. Preliminary experiments showed that a higher lactic acid concentration could be obtained from the wheat and soybean straw. However, soybean straw was chosen as the substrate for lactic acid production owing to its high protein content. The maximum lactic acid yield (0.8 g/g) and lactic acid productivity (0.61 g/(l/h)) were obtained with an initial reducing sugar concentration of 35 g/l at 30℃ when using Lactobacillus casei (10% inoculum) for a 42 h fermentation period. Thus, the experimental results demonstrated the feasibility of using a soybean straw enzymatic hydrolysate as a substrate for lactic acid production.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.1
• /
• pp.8-13
• /
• 2010

The angiotensin converting enzyme (ACE) inhibition effect of soybean protein isolate hydrolysate was studied using protease. Soybean protein isolate was hydrolysed by seven enzymes (Alcalase 2.4 L, Flavourzyme 500 MG, GC 106, Multifect Neutral, Neutrase 0.8 L, Papain 30,000 and Protamex), enzyme concentrations (0, 0.5, 1.0 and 1.5%), at various hydrolysis times (0, 1, 2, 3, 4, 5 and 6 hr) and suspension concentrations (1, 5, 7, 10 and 15%). Absorbance at 280 nm, brix and ACE inhibitory activity of soybean protein isolate hydrolysates were investigated. Absorbance at 280 nm and brix of Alcalase 2.4 L treatment were higher than other enzyme treatments. The optimum condition of hydrolysis was Alcalase 2.4 L, 1% enzyme concentration, 5% suspension concentration for 4 hr. $IC_{50}$ value of ACE inhibitory activity of soybean protein isolate hydrolysate was $79.94 {\mu}g/mL$. These results suggest that soybean isolate protein hydrolysate from Alcalase 2.4 L may be of benefit for developing antihypertensive therapeutics.

• 한국생물공학회:학술대회논문집
• /
• 2000.11a
• /
• pp.765-766
• /
• 2000

Cerebrosides were isolated from soybean, deunjang and chungkukjang and their constituents were investigated. The principal fatty acid of soybean cerebroside was 2-hydroxy-palmitic acid but chungkukjang cerebroside consisted palmitic acid, elaidic acid(trans 18:1), oleic acid and stearic acid. The only sugar in cerebrosides was glucose. TLC analysis of cerebroside hydrolysate elucidated soybean and chungkukjang had same sphingold bases, mainly dihydroxy bases, trans-4, trans-sphingadienine. But, alkali stable glycolipid fractions of chungkukjang and deunjang had $2{\sim}3$ different primary amines.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.25 no.6
• /
• pp.1031-1036
• /
• 1996

Effect of soybean hydrolysate prepared by ultrafiltration(UF-peptide) was evaluated regarding its action on blood pressure, selected biochemical changes in spontaneously hypertensive rats(SHR). Male SHR were divided into three groups and fed diet with 0, 3, 10% UF-peptide for 6 weeks. Development of hypertension was determined by tail cuff method during the experimental period. After the experimental period, angiotension I converting enzyme(ACE) activity in serum and vascular tissue, and lipids level in serum were measured. Spontaneous elevation of blood pressure was suppressed by the UF-peptide supplementation after two weeks of feeding. After five weeks of feeding the development of hypertension was significantly inhibited in the UF-peptide administered groups compared to the control. In addition, the UF-peptide was effective for lowering serum lipids level such as triglyceride and total cholesterol, as well as ameliorating some pathological changes in SHR.

• Preventive Nutrition and Food Science
• /
• v.17 no.3
• /
• pp.223-227
• /
• 2012

This study examined the effects of corn gluten (CG), wheat gluten (WG), and soybean protein isolate (SPI), as well as their hydrolysates, on weight reduction in rats fed a high-fat diet. Eight-month-old male Sprague-Dawley rats (n=70) were fed a high-fat diet (40% of the calories were fat) for 4 weeks. Rats were then randomly divided into seven groups and were fed isocaloric diets with different protein sources for 8 weeks. The protein sources were casein (control group), intact CG (CG group), CG hydrolysate (CGH group), intact WG (WG group), WG hydrolysate (WGH group), intact SPI (SPI group), and SPI hydrolysate (SPIH group). Body weight gain, adipose tissue weights, lipid profiles in plasma and liver; and hepatic activities of carnitine palmitoyl transferase, fatty acid synthase (FAS), malic enzyme, and glucose-6-phosphate dehydrogenase were assessed. The CGH group showed significant weight reduction compared with the other groups. Epididymal fat pad and plasma triglycerides in the CGH group were the lowest and were significantly different than those in the control group. FAS activity in the CGH group was significantly lower than that in the other groups. In conclusion, the CGH diet of these experimental animals demonstrated a weight-reducing effect by lowering the adipose tissue weight and by affecting the activities of hepatic lipogenic enzymes.

• Food Science and Preservation
• /
• v.12 no.5
• /
• pp.460-464
• /
• 2005

In order to produce functional soy hydrolysates, we investigated the characteristics of soy hydrolysates prepared with 4 kinds of commercial proteases. The yield was high in protease(B), in which 43.2% soy flour and 61.6% SPI were obtained. The solubility and the contents of total phenolic compound were greatly increased by the treatment of protease(B) along with protease(C). The calcium intolerance was improved after the protease(B) treatment in soy flour or Soybean Protein isolate (SPI). Consideration for the physicochemical characteristics including yield, protease(B) has potential application for the production of soy hydrolysates. After the protease treatment, the beany flavor of soy flour became weak and the bitter taste was strong in both soy flour and SPI. However, there was no difference of beany flavor and bitter taste among delete protease hydrolysates. Nevertheless, further modifications and improvements to the sensory characteristics would be required for the development of a range of products with the hydrolysate.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.22 no.2
• /
• pp.226-233
• /
• 1993

Enzymatic hydrolysates of food proteins (defatted soybean cake, egg albumin and casein) were tested for inhibitory activity against angiotensin-I converting enzyme (ACE). Food proteins were hydrolysed with complex enzyme, bromelain, alcalase, $\alpha$-chymotrypsin, trypsin, papain and pepsin by heating method. The hydrolysates obtained from the treatment of complex enzyme and bromelain showed the higher ACE inhibitory activity. ACE inhibitory activity of hydrolysates exhibited a tendency to be increased until 8hrs and increased with increment of concentration. The activity was also stable by heat treatment at 10$0^{\circ}C$ for 20min. Molecular weight of active fraction was about 1, 400 and defatted soybean cake hydrolysate below 1, 400 in case of defatted soybean cake hydrolysate treated with alcalase. Amino acid of the active fractions was abundant in Asp, Glu, Lys, lle, Leu, Ala and Val.

• KSBB Journal
• /
• v.23 no.6
• /
• pp.509-512
• /
• 2008

The hydrolysis reaction of soybean oil was conducted experimentally by various source enzymes. The analytical result of hydrolysate of soybean oil showed that the compositions were linoleic acid, olic acid, palmitic acid, and stearic acid in order. The enzymes CR-E and CC-E from Candida rufosa and Candida cylindracea had two hold or more hydrolysis conversions than those of Lipase 16, Novozyme 871, and Lipolase-100L under the same conditions. Therefore CR-E and CC-E were selected for further experiments. These two enzymes had similar ranges of optimun conditions as follows: pH 3-6, $35-45^{\circ}C$, and water to soybean oil ratio of 3.3 or above. They finally got conversions 95% above.

• KSBB Journal
• /
• v.26 no.1
• /
• pp.41-48
• /
• 2011

To enhance cyclo-His-Pro (CHP) content, soybean hydrolysate was obtained using the strains isolated from Chungkukjang and further purified by various purification steps. First, twenty two strains were screened from Chungkukjang containing high level of CHP. Among them, the strain No. 12, which showed higher productivity of CHP from soybean ferment and have homologous sequence with 16S rDNA of Bacillus amyloliquefaciens, was named B. amyloliquefaciens CHP-12. Through various purification processes, CHP was concentrated from soybean ferment using ultrafiltration, which showed the best efficiency of CHP production, with the yield (71.3%) and CHP content (2.14 mg/g). Moreover, when glucose tolerance test was performed in Type I Sprague-Dawley rat induced by streptozotocin using the soybean ferments [0.5 g soybean ferment/kg body weight (CHP-0.5 group)] and 1.0 g soybean ferment/kg body weight (CHP-1.0 group), there were significant differences in glucose levels between diabetes-control group (265.3 mg/dL) and soybean ferment-treated groups (CHP-0.5 group: 84.3 mg/dL and CHP-1.0 group: 85.3 mg/dL) 120 min after glucose injection (2 g/kg body weight) (p < 0.05). Accordingly, it is suggested that the soybean ferment containing high level of CHP might be a candidate material as an anti-diabetic supplement for manufacturing functional healthy foods.