分别用碱性蛋白酶、中性蛋白酶、木瓜蛋白酶、胃蛋白酶和胰蛋白酶制备山杏仁蛋白酶水解物,通过格里斯实验和ELISA方法,研究山杏仁蛋白酶水解物对巨噬细胞产生炎症因子NO、TNF-α和IL-1β的影响。结果表明山杏仁木瓜蛋白酶水解物显著抑...分别用碱性蛋白酶、中性蛋白酶、木瓜蛋白酶、胃蛋白酶和胰蛋白酶制备山杏仁蛋白酶水解物,通过格里斯实验和ELISA方法,研究山杏仁蛋白酶水解物对巨噬细胞产生炎症因子NO、TNF-α和IL-1β的影响。结果表明山杏仁木瓜蛋白酶水解物显著抑制炎症因子NO、TNF-α和IL-1β产生,其抑制率分别为62%、11%和21%,而其它四种蛋白酶水解物没有显示明显的抗炎作用。将山杏仁木瓜蛋白酶水解物分离制备为5~10,3~5,1~3 k Da和小于1 k Da等不同分子量组分,进一步研究其抗炎活性,结果表明小于1 k Da低分子量组分具有较高抗炎活性,其对NO、TNF-α和IL-1β产生的抑制率分别为81%、59%和46%。分析氨基酸组成与含量结果表明,抗炎活性较强的小于1 k Da组分中,疏水性氨基酸和亲水性氨基酸含量均较高,同时谷氨酸、天冬氨酸和精氨酸等具有抗炎作用的氨基酸含量也较高。以上结果表明,山杏仁蛋白被木瓜蛋白酶水解后能够释放抗炎生物活性肽,该活性肽的分子量小于1 k Da,可能是具有两亲性的结构。展开更多
[Objective] To investigate the optimal enzyme for the hydrolysis of corn gluten meal and the optimal hydrolysis conditions for the enzyme. [Method] Nine kinds of enzymes were used to hydrolyze the corn gluten meal, us...[Objective] To investigate the optimal enzyme for the hydrolysis of corn gluten meal and the optimal hydrolysis conditions for the enzyme. [Method] Nine kinds of enzymes were used to hydrolyze the corn gluten meal, using the formaldehyde titration method for the determination of hydrolysis degree, and orthogonal test was used to determine the optimal hydrolysis conditions for double enzymes hydrol- ysis of corn gluten meal. [Result] The optimal pretreatment condition for corn gluten meal is heating at 121 ~C for 30 min. The double enzyme hydrolysis for the pro- treated corn gluten meal using 2709 alkaline protease and flavourzyme showed that the degree of hydrolysis could reach 32.4% with enzyme addition amount of 4%, hy- drolysis time of 4 h at 45℃ and pH=7.0. [Conclusion] This study laid the foundation for the study on the preparation of bioactive peptides such as oligopeptide with high F value and antihypertensive peptides, further improving the corn intensive process- ing industrial chain.展开更多
Three kinds offish frame protein hydrolysates （PPH, APH and FPH） were prepared from fish frame of red drum （ Sciaenops ocellatus ） by papain, alkaline proteinase and flavorzyme treatment. The hydrolysates were mai...Three kinds offish frame protein hydrolysates （PPH, APH and FPH） were prepared from fish frame of red drum （ Sciaenops ocellatus ） by papain, alkaline proteinase and flavorzyme treatment. The hydrolysates were mainly composed of peptide （83.5 % -84.6% ） and displayed different molecular weight distribution pattern. The protective effects of hydrolysates on the freeze-induced denaturation of myofibrillar protein （Mf） from bighead carp （Aristichthys nobilis） mince during storage at -20℃ for 12 weeks were investigated. The hydrolysate （5 % dried weight/wet weight） reduced the freeze-induced denaturation of Mf as evidenced by the lowered decrease in Ca-ATPase activity and reactive sulfllydryl contents as well as the impeded increase in surface hydrophobicity. Microscopic photographs indicated that the hydrolysates inhibited the growth of ice crystal in fish mince, and then prevented the aggregation of Mf during frozen storage. The protective effects of hydrolysates on freeze-induced denaturation of Mf were influenced by the molecular weight distribution. PPH had strongest cryoprotective ability among three hydrolysates.展开更多
Gelatin extracted from the body wall of the sea cucumber （Stichopus japonicus） was hydrolyzed with flavourzyme. Low-molecular-weight gelatin hydrolysate （LMW-GH） of 700-- 1700 Da was produced using an ultrafiltrat...Gelatin extracted from the body wall of the sea cucumber （Stichopus japonicus） was hydrolyzed with flavourzyme. Low-molecular-weight gelatin hydrolysate （LMW-GH） of 700-- 1700 Da was produced using an ultrafiltration membrane bioreaetor system. Chemiluminescence analysis revealed that LMW-GH scavenges high free radicals in a concentration-dependent manner; IC50 value for superoxide and hydroxyl radicals was 442 and 285 μgmL-1, respectively. LMW-GH exhibited excellent inhibitory characteristics against melanin synthesis and tyrosinase activity in B16 cells. Furthermore, LMW-GH notably increased in- traeellular glutathione （GSH）, which in turn suppressed melanogenesis. LMW-GH performs antioxidation activity, holding the potential of being used as a valuable ingredient in function foods, cosmetics and pharmaceuticals or nutriceuticals.展开更多
The growth ofCandida utilis NRRL Y-1084 in acid and enzymatic hydrolysates of cassava peel and on glucose in a mineral salts medium was investigated in aerobic submerged cultivation. Kinetic and stoichiometric paramet...The growth ofCandida utilis NRRL Y-1084 in acid and enzymatic hydrolysates of cassava peel and on glucose in a mineral salts medium was investigated in aerobic submerged cultivation. Kinetic and stoichiometric parameters for growth were determined. The cardinal temperatures of this yeast strain were 14 ℃, 33 ℃ and 41 ℃. C. utilis exhibited no absolute requirement for growth factors, although its maximum specific growth rate （μmax） was higher in the mineral salts medium with yeast extract than without, but its biomass yield coefficient （Yx/s） did not differ much in these two media. In the enzymatic hydrolysate, its Yx/s value on sugar was 0.44 with a μmax of 0.35 h^-1, whereas the corresponding values were 0.52 and 0.48 h^-1 in the acid hydrolysate and 0.50 and 0.37 h^-1 in the mineral salts medium without yeast extract. The crude protein content of biomass grown in the glucose medium and the acid and enzymatic hydrolysates were 47.5%, 49.1% and 56.7%, respectively. The amino acid profile of the yeast biomass compared favourably with the FAO standard. Cassava peel hydrolysate has potential as a cheap carbohydrate feedstock for the production of yeast single cell protein by using C. utilis.展开更多
文摘分别用碱性蛋白酶、中性蛋白酶、木瓜蛋白酶、胃蛋白酶和胰蛋白酶制备山杏仁蛋白酶水解物,通过格里斯实验和ELISA方法,研究山杏仁蛋白酶水解物对巨噬细胞产生炎症因子NO、TNF-α和IL-1β的影响。结果表明山杏仁木瓜蛋白酶水解物显著抑制炎症因子NO、TNF-α和IL-1β产生,其抑制率分别为62%、11%和21%,而其它四种蛋白酶水解物没有显示明显的抗炎作用。将山杏仁木瓜蛋白酶水解物分离制备为5~10,3~5,1~3 k Da和小于1 k Da等不同分子量组分,进一步研究其抗炎活性,结果表明小于1 k Da低分子量组分具有较高抗炎活性,其对NO、TNF-α和IL-1β产生的抑制率分别为81%、59%和46%。分析氨基酸组成与含量结果表明,抗炎活性较强的小于1 k Da组分中,疏水性氨基酸和亲水性氨基酸含量均较高,同时谷氨酸、天冬氨酸和精氨酸等具有抗炎作用的氨基酸含量也较高。以上结果表明,山杏仁蛋白被木瓜蛋白酶水解后能够释放抗炎生物活性肽,该活性肽的分子量小于1 k Da,可能是具有两亲性的结构。
文摘[Objective] To investigate the optimal enzyme for the hydrolysis of corn gluten meal and the optimal hydrolysis conditions for the enzyme. [Method] Nine kinds of enzymes were used to hydrolyze the corn gluten meal, using the formaldehyde titration method for the determination of hydrolysis degree, and orthogonal test was used to determine the optimal hydrolysis conditions for double enzymes hydrol- ysis of corn gluten meal. [Result] The optimal pretreatment condition for corn gluten meal is heating at 121 ~C for 30 min. The double enzyme hydrolysis for the pro- treated corn gluten meal using 2709 alkaline protease and flavourzyme showed that the degree of hydrolysis could reach 32.4% with enzyme addition amount of 4%, hy- drolysis time of 4 h at 45℃ and pH=7.0. [Conclusion] This study laid the foundation for the study on the preparation of bioactive peptides such as oligopeptide with high F value and antihypertensive peptides, further improving the corn intensive process- ing industrial chain.
文摘Three kinds offish frame protein hydrolysates （PPH, APH and FPH） were prepared from fish frame of red drum （ Sciaenops ocellatus ） by papain, alkaline proteinase and flavorzyme treatment. The hydrolysates were mainly composed of peptide （83.5 % -84.6% ） and displayed different molecular weight distribution pattern. The protective effects of hydrolysates on the freeze-induced denaturation of myofibrillar protein （Mf） from bighead carp （Aristichthys nobilis） mince during storage at -20℃ for 12 weeks were investigated. The hydrolysate （5 % dried weight/wet weight） reduced the freeze-induced denaturation of Mf as evidenced by the lowered decrease in Ca-ATPase activity and reactive sulfllydryl contents as well as the impeded increase in surface hydrophobicity. Microscopic photographs indicated that the hydrolysates inhibited the growth of ice crystal in fish mince, and then prevented the aggregation of Mf during frozen storage. The protective effects of hydrolysates on freeze-induced denaturation of Mf were influenced by the molecular weight distribution. PPH had strongest cryoprotective ability among three hydrolysates.
基金supported by the National High-Tech Research and Development Project of China (No.2007AA091805)National Natural Science Foundation of China (Nos.30871944 and 30972284)National Key Technology Research and Development Program of China (No.2008BAD94B05)
文摘Gelatin extracted from the body wall of the sea cucumber （Stichopus japonicus） was hydrolyzed with flavourzyme. Low-molecular-weight gelatin hydrolysate （LMW-GH） of 700-- 1700 Da was produced using an ultrafiltration membrane bioreaetor system. Chemiluminescence analysis revealed that LMW-GH scavenges high free radicals in a concentration-dependent manner; IC50 value for superoxide and hydroxyl radicals was 442 and 285 μgmL-1, respectively. LMW-GH exhibited excellent inhibitory characteristics against melanin synthesis and tyrosinase activity in B16 cells. Furthermore, LMW-GH notably increased in- traeellular glutathione （GSH）, which in turn suppressed melanogenesis. LMW-GH performs antioxidation activity, holding the potential of being used as a valuable ingredient in function foods, cosmetics and pharmaceuticals or nutriceuticals.
文摘The growth ofCandida utilis NRRL Y-1084 in acid and enzymatic hydrolysates of cassava peel and on glucose in a mineral salts medium was investigated in aerobic submerged cultivation. Kinetic and stoichiometric parameters for growth were determined. The cardinal temperatures of this yeast strain were 14 ℃, 33 ℃ and 41 ℃. C. utilis exhibited no absolute requirement for growth factors, although its maximum specific growth rate （μmax） was higher in the mineral salts medium with yeast extract than without, but its biomass yield coefficient （Yx/s） did not differ much in these two media. In the enzymatic hydrolysate, its Yx/s value on sugar was 0.44 with a μmax of 0.35 h^-1, whereas the corresponding values were 0.52 and 0.48 h^-1 in the acid hydrolysate and 0.50 and 0.37 h^-1 in the mineral salts medium without yeast extract. The crude protein content of biomass grown in the glucose medium and the acid and enzymatic hydrolysates were 47.5%, 49.1% and 56.7%, respectively. The amino acid profile of the yeast biomass compared favourably with the FAO standard. Cassava peel hydrolysate has potential as a cheap carbohydrate feedstock for the production of yeast single cell protein by using C. utilis.
