摘要
本研究以酱渣为原料,研究了中性蒸煮、酸性蒸煮、纤维素酶酶解与中性蒸煮联合酶解法制得的可溶性膳食纤维(SDF)延缓葡萄糖扩散能力及对猪胰腺α-淀粉酶(PPA)抑制机理。所有SDF的葡萄糖透析延迟指数(GDRI)在30min前均达到峰值(15.20%~60.39%),均展现出了PPA抑制活性,质量浓度为100mg/mL时,抑制率为30%~35%。酸性蒸煮制得酱渣SDF(SZ-SDF)具有最好的综合特性,故研究其对于PPA的抑制类型及机制。酶解初始速率与酶浓度的关系曲线及Lineweaver-Burk拟合曲线结果表明,SZ-SDF对PPA的抑制为可逆的线性混合型抑制。荧光猝灭实验结果表明,PPA的荧光发射峰出现在340nm附近,且随着添加SZ-SDF质量浓度的增加荧光强度降低。Stern-Volmer及双对数曲线拟合的结果表明,KSV随着温度升高而减小。SZ-SDF对PPA荧光淬灭类型为静态猝灭。PPA的表面疏水性与SZ-SDF的质量浓度呈负相关。因此,酱渣SDF均具有延缓体外葡萄糖扩散及PPA酶活抑制能力,其抑制PPA酶活性的机制可能是通过降低酶的表面疏水性使内部亲水基团暴露导致酶活性中心结构发生改变。
This research investigated,the ability to retard glucose diffusion and the mechanism of inhibition of porcine pancreaticα-amylase(PPA)of soluble dietary fiber(SDF)obtained from soy sauce residue by neutral high-temperature processing,acidic high-temperature processing,cellulase digesting,and cellulase digesting after high-temperature processing were studied.The glucose dialysis retardation index of all SDFs peaked before 30 min(15.20%~60.39%),demonstrated PPA inhibitory activity,with inhibition rates of 30%~35%when the concentration was 100 mg/mL.Soy sauce residue SDF produced by acidic high-temperature processing(SZ-SDF)has the most favorable comprehensive properties.SZ-SDF was selected for further investigation of PPA inhibition type and mechanism.The results of the curves of the initial rate of enzyme digestion versus enzyme concentration and the Lineweaver-Burk fitting curves indicated that SZ-SDF exerted reversible inhibition on PPA in a mixed-type inhibition manner.The results of fluorescence quenching experiments showed that the fluorescence emission peak of PPA appeared near 340 nm,and the fluorescence intensity decreased with the increase of the mass concentration of SZ-SDF.The results of Stern-Volmer and double logarithmic curve fitting showed that KSV decreased with increasing temperature and the type of PPA fluorescence quenching by SZ-SDF was static quenching.Surface hydrophobicity of PPA was negatively correlated with the mass concentration of SZ-SDF.Therefore,SDFs of soy sauce residue had the ability to retard in vitro glucose diffusion and inhibit PPA.The mechanism of its inhibition might be through the reduction of the surface hydrophobicity of PPA so that the internal hydrophilic groups were exposed leading to changes in the structure of the enzyme's active center.
作者
许树荣
夏忠悦
邓莎
许訢彧
张佳琪
吕远平
XU Shu-rong;XIA Zhong-yue;DENG Sha;XU Xin-yu;ZHANG Jia-qi;LV Yuan-ping(College of Biomass Science and Engineering,Sichuan University,Chengdu,Sichuan 610065,China;New Hope Dairy Co.,Ltd.,Chengdu,Sichuan 610000,China)
出处
《粮油食品科技》
北大核心
2025年第5期212-222,共11页
Science and Technology of Cereals,Oils and Foods
基金
四川大学泸州市人民政府战略合作项目一般项目“酱渣综合利用关键技术研究及其产业化应用”(2021CDLZ 18)。
