• Journal of Nutrition and Health
• /
• v.43 no.4
• /
• pp.342-350
• /
• 2010

This study was aimed to investigate whether soy protein hydrolysates had beneficial effects on serum and tissue lipid contents and appetite-related hormones as compared with intact soy protein. Four-week-old male Sprague-Dawley rats were fed AIN-93M diet containing high fat (18% w/w) with low protein (10% w/w). After four weeks, the rats were divided into four groups (n = 8/group) and fed experimental diets with different nitrogen sources and levels, respectively; 10% soy protein isolate (10SPI), 25% soy protein isolate (25SPI), 25% soy protein hydrolysates (25SPH) and 25% soy macro-peptide fractions (25SPP, MW $\geq$ 10,000) for six weeks. Weight gain was significantly higher in 25% nitrogen sources-fed groups than in 10% group (10SPI). In 25SPP, perirenal fat mass and serum total lipid were significantly lower than in other groups. As for appetite-related hormones, serum ghrelin concentration was not shown to be different among groups but leptin concentration was significantly decreased in 25SPP. It can be concluded that soy macro-peptide fractions as compared with intact soy protein may have beneficial effects on reducing fat mass and serum lipid.

• Food Science of Animal Resources
• /
• v.34 no.1
• /
• pp.14-19
• /
• 2014

This study investigated the effects of protease treatments (trypsin, chymotrypsin, and pepsin) under various pressure levels (0.1-300 MPa) for the characteristics of porcine placenta hydrolysates. According to gel electrophoretic patterns, the trypsin showed the best placental hydrolyzing activity followed by chymotrypsin, regardless of the pressure levels. In particular, the peptide bands of tryptic-digested hydrolysate were not shown regardless of applied pressure levels. The peptide bands of hydrolysate treated chymotrypsin showed gradual decreases in molecular weights ($M_w$) with increasing pressure levels. However, the pepsin did not show any evidences of placental hydrolysis even though the pressure levels were increased to 300 MPa. The gel permeation chromatography (GPC) profiles showed that the trypsin and pepsin had better placental hydrolyzing activities under high pressure (particularly at 200 MPa), with lower $M_w$ distributions of the hydrolysates. Pepsin also tend to lower the $M_w$ of peptides, while the major bands of hydrolysates being treated at 300 MPa were observed at more than 7,000 Da. There were some differences in amino acid compositions of the hydrolysates, nevertheless, the peptides were mainly composed of glycine (Gly), alanine (Ala), hydroxyproline (Hyp) and proline (Pro). Consequently, the results indicate that high pressure could enhance the placental hydrolyzing activities of the selected proteases and the optimum pressure levels at which the maximum protease activity is around 200 MPa.

• Food Science of Animal Resources
• /
• v.35 no.3
• /
• pp.360-369
• /
• 2015

Milk proteins have many potential sequences within their primary structure, each with a specific biological activity. In this study, we compared and investigated the bioactivities of hydrolysates of the domestic (A, B) and imported (C, D) skim milk powders generated using papain digestion. MALDI-TOF analysis revealed that all milk powder proteins were intact, indicating no autolysis. Electrophoretic analysis of hydrolysates showed papain treatment caused degradation of milk proteins into peptides of various size. The antioxidant activity of the hydrolysates, determined using 2,2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) and total phenolic contents (TPC) assays, increased with incubation times. In all skim milk powders, the antioxidant activities of hydrolysates were highest following 24 h papain treatment (TPC: A, 196.48 μM GE/L; B, 194.52 μM GE/L; C, 194.76 μM GE/L; D, 163.75 μM GE/L; ABTS: A, 75%; B, 72%; C, 72%; D, 57%). The number of peptide derived from skim milk powders, as determined by LC-MS/MS, was 308 for A, 283 for B, 208 for C, and 135 for D. Hydrolysate A had the highest antioxidant activity and the most potential antioxidant peptides amongst the four skim milk powder hydrolysates. A total of 4 β-lactoglobulin, 4 α_s1-casein, and 56 β-casein peptide fragments were identified as potential antioxidant peptides in hydrolysate A by LC-MS/MS. These results suggest that domestic skim milk could have applications in various industries, i.e., in the development of functional foods.

• Food Science of Animal Resources
• /
• v.22 no.1
• /
• pp.87-93
• /
• 2002

Angiotensiri-I converting enzyme(ACE) catalyst the removal of the C-terminal dipeptide from the angiotensin-I to give the angiotensin-II, a potent peptide that causes constriction of regulation of blood pressure. Recently, ACE inhibitor peptides have been isolated from enzymatic digests of food protein. The aim of this study was to identify bovine casein hydrolysates with ACE inhibitory properties in different enzymatic hydrolysis conditions. The casein were hydrolyzed neutrase, alcalase, protamax, flavourzyme, premed 192, sumizyme MP, sumizyme LP and pescalase alone and with an enzyme combination. Premed 192 produced ACE inhibitory peptides most efficiently. In order to ACE inhibitory peptide produced enzymatic hydrolysis condition were premed 192 added to casein ratio of 1:100(w/w), and incubated at 47$\^{C}$ for 12hrs. Casein hydrolysate gave 50% inhibition(IC$\_$50/ value) of ACE activity at concentration with 248ug/ml(general method) and 265ug/ml(pretreatment method) respectively.

• Food Science of Animal Resources
• /
• v.39 no.6
• /
• pp.966-979
• /
• 2019

Muscle-based by-products are often undervalued although commonly reported having a high amount of natural bioactive peptides. In this study, elastin was isolated from the protein of broiler hen skin while its hydrolysate was prepared using Elastase. Assessment of antioxidative properties of elastin-based hydrolysate (EBH) was based on three different assays; 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical, 2,2'-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical and metal chelating ability. The EBH was purified further using ultrafiltration, gel filtration and Reverse- Phase High-Performance Liquid Chromatography (RP-HPLC). The IC₅₀ of ABTS radical activities for EBH were decreased as EBH further purified using ultrafiltration (EBH III; 0.66 mg/mL)>gel filtration (EB-II; 0.42 mg/mL)>RP-HPLC (EB-II4; 0.12 mg/mL). The sequential identification of the peptide was done by matrix-assisted laser desorption/ionization time-of-flight/time-of-flight mass spectrometry (MALDI-TOF/ TOF-MS) of the potent fractions obtained from RP-HPLC (EB-II4). The presence of hydrophobic amino acids (Val and Pro) in the peptide sequences could potentially contribute to the high antioxidant activity of EBH. The sequences GAHTGPRKPFKPR, GMPGFDVR and ADASVLPK were identified as antioxidant peptides. In conclusion, the antioxidative potential from poultry skin specifically from elastin is evident and can be explored to be used in many applications such as health and pharmaceutical purposes.

• Food Science of Animal Resources
• /
• v.29 no.5
• /
• pp.633-639
• /
• 2009

The principal objective of the current study was to prepare low molecular weight peptides from milk proteins using enzymatic hydrolysis techniques, in an effort to assess the antioxidant activity of these peptides. The casein and whey proteins isolated from fresh milk were treated with several proteolytic enzymes, such as chymotrypsin, pepsin, and trypsin and the resulting low molecular weight peptides were collected by TCA precipitation. Their identity was confirmed by SDS-PAGE analysis. The hydrolysis experiments indicated that whey protein treated with chymotrypsin displayed the highest degree of protein hydrolysis. The antioxidant activity of milk protein hydrolysates was determined by measuring the ABTS-radical scavenging activity. The results of these experiments showed that hydrolysis of the milk protein was effective in increasing their antioxidant activities. Especially, the tryptic digested casein displayed the highest radical scavenging activity (80.7%). The hydrolyzed low molecular weight milk protein was isolated using an ultrafiltration membrane. The casein hydrolysate passed through a membrane with molecular weight cut-off (MWCO) of 3 kDa displayed the strongest antioxidant activity.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.47 no.2
• /
• pp.147-153
• /
• 2021

Collagen hydrolysate (CH) is known to prevent skin aging by stimulating skin dermal fibroblasts to promote synthesis of extracellular matrix such as collagen and elastin. Recently, among the various factors that cause skin aging, advanced glycation end products (AGEs) have received particular attention. However, the effect of CH on AGE accumulation has not been studied. Since CH could affect AGE accumulation by promoting production of skin structural proteins, clinical trial was performed using low molecule collagen peptide (LMCP), which were CH containing 25% tripeptide and 4% Gly-Pro-Hyp. Skin autofluorescence (SAF) values were measured using an AGE reader to evaluate accumulation of AGE in skin. As a result of applying 0.5% and 1.0% LMCP solutions to the subject's forearm for 8 weeks, the SAF value at the test site significantly decreased compared to the control site. Additionally, in vitro test was performed using CCD-986sk to evaluate the promotion of collagen synthesis in skin fibroblasts by LMCP. As a result, 800 ㎍/mL of LMCP significantly increased synthesis of human pro-collagen Iα1 (COL1A1) in CCD-986sk. Through this study, we have confirmed that tropical LMCP applications can promote collagen synthesis to help anti-glycation effects, suggesting that LMCP has potential as an anti-aging cosmetic material.

• Journal of Applied Biological Chemistry
• /
• v.59 no.3
• /
• pp.265-271
• /
• 2016

Recently, liver damage contributes to big percentage of the morbidity and mortality rates worldwide. Excessive intake of alcohol is one of the major causes of liver injury. When liver injury is repeated and becomes chronic, it leads to development of fibrosis and cirrhosis. In the liver, TGF-${\beta}$ is a profibrogenic cytokine, which participates in various critical events cause liver fibrosis. Seahorse (Hippocampus abdominalis) is a common traditional Chinese medicine and has been widely used for centuries. Seahorse has been known to have a variety of bioactivities, such as anti-oxidant, anti-fatigue, and anti-tumor. Peptide is one of the main compounds of seahorse. In this study, we isolated enzymatic hydrolysate from seahorse H. abdominalis by alcalase hydrolysis and investigated the effect of the hydrolysate on liver injury. In the present in vitro studies, the hydrolysate increases cell viability of Chang cells and protects Huh7 cells from ethanol toxicity. In addition, the hydrolysate inhibits TGF-${\beta}$-induced responses. In vivo studies show that the pretreatment of hydrolysate reduces alcohol-induced increases of serum Glutamic oxaloacetic acid transaminase and Glutamic pyruvate transaminase activities and increases liver weight and body weight. These results suggest that seahorse may have a hepatoprotective effect.

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.3
• /
• pp.417-424
• /
• 2003

Inhibitory activities against angiotensin I-converting enzyme (ACE) of enzymatic hydrolysates of porcine skeletal muscle proteins were investigated. Myosin B, myosin, actin, tropomyosin, troponin and water-soluble proteins extracted from pork loin were digested by eight kinds of proteases, including pepsin, $\alpha$-chymotrypsin, and trypsin. After digestion, hydrolysates produced from all proteins showed ACE inhibitory activities, and the peptic hydrolysate showed the strongest activity. In the case of myosin B, the molar concentration of peptic hydrolysate required to inhibit 50% of the activity increased gradually as digestion proceeded. The hydrolysates produced by sequential digestion with pepsin and $\alpha$-chymotrypsin, pepsin and trypsin or pepsin and pancreatin showed weaker activities than those by pepsin alone, suggesting that ACE inhibitory peptides from peptic digestion might lose their active sequences after digestion by the second protease. However, the hydrolysates produced by sequential digestion showed stronger activities than those by $\alpha$-chymotrypsin, trypsin or pancreatin alone. These results suggested that the hydrolysates of porcine meat were able to show ACE inhibitory activity, even if they were digested in vivo, and that pork might be a useful source of physiologically functional factors.

• Applied Biological Chemistry
• /
• v.46 no.2
• /
• pp.130-133
• /
• 2003

A method for separating heme-iron from hemoglobin (Hgb) hydrolysate by dialysis was developed. Recovery of heme-iron increased with increasing Hgb concentration, whereas rejection of peptide and separation effciency expressed by HP ratio (heme-iron/peptide) did not show significant differences. HP ratio increased with increases in the degree of hydrolysis of Hgb and $KH_2PO_4$ concentrations of dialysis solution. Recovery of heme-iron decreased with increase in the pH of dialysis solution due to wash-out of heme-iron across the dialysis membrane caused by increase in solubility of heme-iron. Rejections of peptide were 74.5 and 87.5% (2 and 5 kDa of cut off size, respectively), whereas recovery of heme-iron decreased from 86.5 (2 kDa) to 63.1% (25 kDa). Amounts of heme-iron and peptide of dried heme-iron product were 21.7 and 77.0%, and HP ratio and production yield were 28.2 and 6.5%, respectively.