• Korean Journal of Food Science and Technology
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• v.26 no.4
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• pp.436-441
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• 1994

To investigate the lowering effects of in vitro enzymatic hydrolysis by the treatment of chymotrypsin, trypsin, pancreatin, or protease from Aspergillus oryzae on the antigenicity of whey protein isolate (WPI) against rabbit anti ${\alpha}-LA$ antiserum, competitive inhibition ELISA (cELISA) and passive cutaneous anaphylaxis (PCA) test using guinea pig were performed. The results of cELISA showed that the monovalent antigenicity of the whey protein hydrolysates (WPH) to the antiserum was decreased to $10^{-2.5}-10^{-5.5}$ and less by the hydrolysis. The monovalent antigenicity of the WPH hydrolyzed by trypsin, or protease from Asp. nryzae was much lowered by the pretreatment of heat denaturation. The antigenicity of the WPH hydrolyzed by chymotrypsin, trypsin, or pancreatin was much lowered by the pretreatment of pepsin. Especially, the antigenicity of TDP (trypic hydrolysate with pretreatment of heat and pepsin) was found almost to be removed. However, there was not consistency between degree of hydrolysis(DH) and the monovalent antigenicity of the WPH. By the heterologous PCA it was found that all of the PGPH lost the polyvalent antigenicity regardless of the pretreatments although WPI and ${\alpha}-LA$ had the positive high antigenicity. The results suggested that the peptides derived from ${\alpha}-LA$ in WPH could bind specific antibodies but they could not induce allergy. Therefore, it was elucidated that the allergenicity of ${\alpha}-LA$ in whey protein could be destroyed easily by the enzymatic hydrolysis.

• Korean Journal of Agricultural Science
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• v.39 no.3
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• pp.395-405
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• 2012

Lipozyme TL IM-catalyzed esterification was carried out to produce functional hard fat (structured lipid, SL) using palm stearin (PS) and hydrolysate of pomegranate seed oil (HPSO) of 1:6 molar ratio. HPSO contained conjugated linolenic acid (CLnA, about 80%). The reaction was performed at non-solvent system and solvent (n-hexane) system using Lipozyme TL IM (10% of total substrates, w/w) for 12, 24, and 72 hr in a shaking water bath ($55^{\circ}C$ and 185 rpm), respectively. SL synthesized in non-solvent system (NH-SL) and SL synthesized in n-hexane system (H-SL) were refined after deacidification, respectively. Their physicochemical properties were compared to obtain desirable functional hard fat. The content of CLnA in NH-SL increased from 34.38% to 40.63% with increasing reaction time. Similar results also observed in H-SL resulting in 36.81~45.83% of CLnA. In triacylglycerol (TAG) composition, the main molecules of LnLnLn (Ln=linolenic acid, PN=36) and the LnLnP (P=palmitic acid, PN=40) were newly synthesized in NH-SL and H-SL with increasing reaction time. After 72 hr reaction, iodine values of NH-SL (136.49) and H-SL (140.37) showed high values because of the high content of CLnA. Solid fat index (SFI) in NH-SL was higher than that in H-SL at each measured temperature. The predominant polymorphic forms of NH-SL and H-SL obtained after esterification for 72 hr were the desirable crystalline structure of the ${\beta}$' form.

• Journal of the Korean Applied Science and Technology
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• v.38 no.3
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• pp.824-831
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• 2021

1, 2-Octanediol galactoside (OD-gal) has been synthesized from 1, 2-octanediol (OD), as a safer cosmetic preservative, using recombinant Escherichia coli β-galactosidase (β-gal). To confirm the molecular structure of synthesized OD-gal, mass spectrometry and NMR (¹H- and ¹³C-) spectroscopy of OD-gal were carried out. In the reaction mixture, a sodium adduct ion of OD-gal (m/z=331.1732) was identified using mass spectrometry analysis. In addition, ¹H NMR spectrum of OD-gal showed multiple peaks corresponding to the galactosyl group, which is evidence of galactosylation on OD. Downfield proton peaks at δ_H 4.39 ppm and multiple peaks from δ_H 3.98~3.55 ppm were indicative of galactosylation on OD. Up field proton peaks at δ_H 1.52~1.26 ppm and 0.89 ppm showed the presence of CH₂ and CH₃ protons of OD. ¹³C NMR spectrum revealed the presence of 24 carbons suggestive of α- and β-anomers of OD-gal. Among 14 carbon peaks from each anomer, the 4 peaks at δ_C 31.4, 29.0, 22.3, and 13.7 ppm were assigned to be overlapped showing only 24 peaks out of a total of 28 peaks. The mass value from mass spectrometry analysis of OD-gal, and ¹H and ¹³C NMR spectral data were in good agreement with the expecting structure of OD-gal. Finally, we identified a galactose molecule from the hydrolysate of OD-gal using β-gal. We are expecting that through future study it will eventually be able to develop a safe cosmetic preservative.