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

• Applied Biological Chemistry
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• v.42 no.1
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• pp.49-57
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• 1999

Enzymatic hydrolysis with tuna pyloric caeca crude enzyme(TPCCE) was performed to recover a protein hydrolysate from hoki frame, fish processing by-product. Optimum hydrolytic conditions were pH 10.0, temperature $50^{\circ}C$, and incubation time 12 hrs, and then the degree of hydrolysis was about 60%. The yield of the hydrolysate from hoki frame by enzymatic hydrolysis was approximately 77% on a dry weight basis. The prepared protein hydrolysates were also fractionated through a series of 30, 10, 5 and 1 kDa molecular weight cut-off (MWCO) membranes in order to investigate the effect of their functionalities according to the difference of their molecular size. As the result of studying functionalities of the hydrolysates, 1 K hydrolysate showed the highest solubility over all pHs, and 30 and 10 K hydrolysate showed more excellent emulsifying property and whippability than the other hydrolysates.

• Journal of the Korean Home Economics Association
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• v.36 no.8
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• pp.51-61
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• 1998

This paper discussed the assessment of hand of polyester fabrics changed by alkaline hydrolysis. This study analyzed the relations between the change of mechanical property and the hand value according to the weight loss of polyester fabrics. The results are as follows; Objective hand by KES-FB system, revealed that for tensile properties, as the weight loss increased, WT, RT increased and LT decreased. For bending properties, as the weight loss increased, B and 2HB showed smaller values. For shear properties, as the weight loss increased, G, 2HG and 2HG5 decreased. For surface properties, as the weight loss increased, MIU increased, but MMD and SMD did not show any trend. For compression properties, LC, WC and RC did not show significant differences according to the degree of weight loss. In case of hand value, Koshi(stiffness), Hari(anti-drape stiffness), Kisimi(scrooping feeling) and Shinayakasa(flexibility with soft feeling) showed a meaningful results depending on the degree of weight loss. However, Shari(crispness) and Fukurami(fullness and softness) did not show meaningful result. Koshi, Hari and Shinayakasa are high correlation with tensile property, bendibg property shear properties, thickness and weight. Kisimi is high correlation with tensile property, bending property, thickness and weight. Shari, Fukurami and THV did not show any meaningful difference whth any mechanical properties.

• Journal of Applied Biological Chemistry
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• v.42 no.2
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• pp.81-84
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• 1999

Blood glue was prepared to reutilize porcine blood. Plasma proteins after lyophilization were treated by addition of wood flour, sodium hydroxide, sodium silicate, and hydrated lime to make blood glue with a suitable adhesivity. Characteristics of the prepared blood glue was monitored by measuring the viscosity with time, and the relationship between degree of hydrolysis of plasma proteins by addition of various amounts of sodium hydroxide and adhesivity was studied. To prevent the emission of formaldehyde during manufacturing of plywood by blood glue, the cross-linking reaction of plasma protein with formaldehyde was also examined. Fourier transform infrared, circular dichroism, and fluorescence spectroscopy study showed that blood plasma proteins react with formaldehyde, resulting in removal of formaldehyde by cross-linking reaction.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.43 no.1
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• pp.29-35
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• 2011

Since the role of lignin in the wood cell wall is to keep integrity and structure rigidity of lignocellulosic substrate, lignin of the cell wall has to be destroyed before enzymatic hydrolysis of wood polysaccharides. The aspen wood meals were delignified with ozone in acidic condition. The chemical characteristics of wood meal were investigated. The 60% of lignin and almost zero % of polysaccharides in aspen wood meal was degraded with 10min. ozone treatment. The phenolic hydroxyl groups of lignin in ozonated wood meal were increased with ozonation time. The sugar composition of ozonated wood meal showed that the hemicellulose was more susceptible to ozonation than cellulose. The yield of aldehyde was increased in some degree with 10min. ozone treatment and decreased with longer ozone treatment.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.2
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• pp.148-153
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• 2006

Effects of ${\alpha}$-chymotrypsin modification on degree of hydrolysis (DH), solubility, emulsifying capacity and thermal aggregation of laboratory-purified soy protein isolate (SPI) using a lipoxygenase-defected soybean (Jinpum-kong) and commercial soy protein isolate (Supro 500E) were compared. SPIs were hydrolyzed by ${\alpha}$-chymotrypsin at pH 7.8 and $37^{\circ}C$ for 30 min. DHs of Supro 500E and Jinpum-kong SPI were increased by ${\alpha}$-chymotrypsin modification, and DH of Supro 500E was higher than that of Jinpum-kong SPI. DH of ${\alpha}$-chymotrypsin treated Jinpum-kong SPI was similar with untreated Supro 500E and DH of treated Supro 500E was the highest. Solubility, emulsifying capacity and thermal aggregation of SPIs were increased by ${\alpha}$-chymotrypsin modification, and these changes were highly related to changes in DH. Functional properties of Supro 500E were higher than Jinpum-kong SPI in both of untreated and ${\alpha}$-chymotrypsin treated SPIs.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 1999.11b
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• pp.56-60
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• 1999

In this paper, a series of amphoteric polyacrylamide(PAM) with different molecular weight and charge were synthesized and used as retention and dewatering aids. Better products had been selected and tested under varied conditions. Effects of molecular weight, cationic charge density, degree of hydrolysis and other factors of PAM on retention and dewatering of papermaking were also considered. Finally, synthesized quaternary and tertiary ammonium amphoteric polyacrylamide were practised in paper mill trial.

• Toxicological Research
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• v.23 no.1
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• pp.47-53
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• 2007

Amygdalin is a cyanogenic glycoside which is commonly found in almonds, bamboo shoots, and apri-cot kernels, and peach kernels. Amygdalin was first hydrolysed into prunasin, then degraded into cyanohydrin by sequential two-stage mechanism. The objective of this study was to examine the amygdalin decomposition and cyanide formation at various in vitro conditions, including acid, enzyme and anaerobic microbes (AM) in human feces (HF). In acid hydrolysis mimicking gastric environment, amygdalin was degraded to cyanide up to 0.2% in specific pH. In contrast, enzyme assay showed higher cyanide generation either by ${\beta}$-glucosidase, or by incubation with microbe. In conclusion, we are convinced of cyanide generation are occurred mainly by microbiological activities of the gut flora up to 41.53%. After ingestion with some staff, the degree and site of degradation in an organism is a key parst of regulatory decision making of that staff.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.5
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• pp.784-787
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• 1997

Enzymatically hydrolyzed soy sauce(eHSS) was prepared by the treatment of defatted soy flake using two types of proteases, followed by maillard reaction and formulation with some ingredients. The eHSS was mixed with fermented soy sauce(FSS) to make enzymatically hydrolyzed mixed soy sauce(eHMSS). The properties and sensory characteristics were evaluated and compared with commercially available soy sauces. The control of salt and total nitrogen contents in eHSS and eHMSS was easy, and the production of soy sauce of low salt and high protein was possible. However, the free amino acid content of eHSS was lower than FSS. due to lower degree of hydrolysis. In sensory evaluation, the eHSS have no loss taste and overall acceptance than FSS. Consequently, the eHSS and eHMSS have the potential for use with FSS to produce high quality soy sauce of low salt and high protein contents.

• Journal of Microbiology
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• v.43 no.6
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• pp.487-492
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• 2005

This study demonstrated that the brown rot basidiomycete Fomitopsis palustris was able to degrade crystalline cellulose (Avicel). This fungus could also produce the three major cellulases (exoglucanases, endoglucanases, and $\beta-glucosidase$) when the cells were grown on $2.0\%$ Avicel. Avicel degraded by F. palustris showed a decrease in relative crystallinity from $83\%\;to\;78.5\%$ after 14 days of incubation. The characterization study indicated that optimum pH was 4.5 and optimum temperature was $70^{\circ}C$ for exoglucanase (cellobiohydrolase) activity. Hydrolysis of Avicel by the crude enzyme from F. palustris yielded 1.6 mg/ml of glucose after 43 h, which corresponded to a cellulose conversion degree of $3.2\%$. Therefore, this study revealed for the first time that the brown rot basidiomycete F. palustris produces cellulases capable of yielding soluble sugars from crystalline cellulose.