菊芋酶解制备低聚果糖糖浆的工艺优化及功能评价

菊芋块茎富含菊糖,是制备低聚果糖（Fructooligosaccharides,FOS）的主要原料之一,新鲜菊芋块茎直接酶法加工用于功能性糖浆的制备可以丰富菊芋综合加工的应用。本研究以新鲜菊芋块茎为原料,通过系统研究菊芋内源酶、菊粉内切酶、葡聚糖内切酶、木聚糖酶、聚半乳糖醛酸酶和单宁酶在鲜菊芋酶法加工制备低聚果糖糖浆中的作用规律和酶解效果,建立并优化了酶法制备低聚果糖糖浆的工艺。结果表明,最优酶解工艺如下：菊芋浆在50℃和pH5.0条件下,加入0.08 U/g单宁酶酶解4 h,再加入0.08 U/g葡聚糖内切酶、0.08 U/g木聚糖酶、0.07 U/g聚半乳糖醛酸酶和12 U/g菊糖内切酶组合酶解8 h,酶解液浓缩2倍后获得低聚果糖糖浆成品。成品中低聚果糖和单宁的含量分别为53.72和3.11 g/L,DPPH自由基清除率、羟基自由基清除率和总抗氧化能力分别为82.23%、30.47%和2.78μmol/mL。以制备的低聚果糖糖浆为唯一碳源替代MRS培养基中的葡萄糖,植物乳杆菌、嗜热链球菌和副干酪乳杆菌的生长速率较未经酶解的菊芋原浆作为MRS培养基的唯一碳源时,分别提高了33.33%...     

响应面法优化β-半乳糖苷酶法制备低聚半乳糖工艺

本文以乳糖为起始原料,在单因素实验的基础上,结合响应面分析法考察加酶量、反应温度、反应时间、反应pH等因素对低聚半乳糖总产率和低聚半乳四糖产率的影响,优化β-半乳糖苷酶法制备低聚半乳糖工艺。结果表明,β-半乳糖苷酶法制备低聚半乳糖的最佳工艺参数为起始乳糖浓度300 g/L、加酶量8.25 U/g乳糖、反应温度49 ℃、反应时间16 h、反应pH5.6。在此条件下,低聚半乳糖总产率为14.61%,低聚半乳四糖产率为3.31%。该方法针对性提高高聚合度低聚半乳糖的产率,可为低聚半乳糖的功能性应用及特医食品的研发提供参考。     

功能性低聚糖的制造与生物技术

介绍了低聚异麦芽糖、低聚果糖、低聚木糖的结构组成及特性，研究了酶法制备的工艺流程     

酶法制备低聚木糖研究进展

本文对游离酶法制备低聚木糖的碱-酶法、酸-酶法、蒸汽爆破-酶法和微波辅助-酶法,以及固定化酶法制备低聚木糖的工艺过程与工艺参数分别进行总结和比较,以期为进一步的研究提供参考。     

酶法处理油茶籽壳制备低聚木糖工艺的优化

优化酶解处理油茶籽壳制备低聚木糖的工艺条件。以油茶籽壳为原料,经碱法制备木聚糖粗提液。以所得的木聚糖粗提液为原料,低聚木糖浓度为考核指标,酶解温度、木聚糖酶使用量、酶解时间和木聚糖底物浓度为变量因子,进行单因素试验。在单因素试验基础上,利用响应面法对酶法制备低聚木糖工艺进行优化研究。结果表明,最佳的制备工艺为:酶添加量5%、酶解时间10 h、酶解温度49℃、底物浓度2%。在此优化酶解工艺条件下,测得低聚木糖浓度为11.63 g/L,比未优化前提高4.63 g/L。试验所得到的酶解处理油茶籽壳制备低聚木糖的工艺条件具有实用价值,能为提高利用油料加工副产物油茶籽壳的附加值提供理论依据。     

微波-酶法处理小麦麸皮制备低聚木糖的工艺研究

以小麦麸皮为原料制备低聚木糖,先微波消解,后加酶水解,研究微波酶法制备低聚木糖过程中微波功率、微波处理时间、液料比、加酶量和酶解时间5个因素对低聚木糖提取率的影响.经单因素和正交试验,确定最佳工艺条件为:微波功率600 W、微波处理时间7 min、加酶量2.5％和酶解时间8h,低聚木糖提取率为47.5％.该工艺成本较低,所得到的粗提取液颜色较浅,便于脱色,明显优于传统单一的微波消解法和酶解法.     

两种制备海藻糖的生物酶转化工艺技术

海藻糖作为具有特殊生物保护功能的非还原性双糖,被广泛应用在食品、医药等各个领域。以双酶法和单酶法为代表的生物酶转化技术是制备海藻糖的研究热点。双酶法以淀粉为原料,在低聚麦芽糖基海藻糖合成酶和低聚麦芽糖基海藻糖水解酶的协同作用下,将直链淀粉转化成海藻糖。双酶法具有原料便宜易得、工艺较成熟、转化率较高等优点,是最早实现酶法工业化生产海藻糖的方法。单酶法直接利用海藻糖合酶将麦芽糖转化为海藻糖。单酶法因为具有反应过程易控、工艺流程简单、副产物少等优点而受到广泛关注。提高酶的耐高温性能及转化效率是目前2种方法的主要研究方向。随着蛋白基因工程领域的发展,生物酶的优化构建技术日趋成熟,为双酶法的进一步完善和单酶法的工业应用奠定了基础。     

响应面法优化玉米芯中低聚木糖的酶法提取工艺

为提高玉米芯中低聚木糖的得率,试验以玉米芯为原料,研究酶法提取低聚木糖的最优工艺条件,对底物浓度、加酶量、酶解温度、酶解时间4个因素分别进行单因素试验,根据单因素试验结果设计BoxBenhnken中心组合试验,以还原糖含量为指标值,采用响应面分析法确定提取低聚木糖的最优工艺参数,并通过HPLC进行水解产物的分析。结果表明:最优工艺条件为底物浓度3%,加酶量40 m L/g(底物),50℃时酶解5 h所得的低聚木糖含量为3.86 mg/m L。水解产物经HPLC分析后发现其中含有较高的木二糖、木三糖等低聚木糖组分,低聚木糖(木二~木五)的相对含量达68.1%,说明优化后的酶法提取工艺能够较好的制备低聚木糖。     

微波—酶法提取低聚木糖的研究

利用微波—酶法在玉米芯中提取低聚木糖,根据实验确定最佳工艺条件为：微波压力为1.5 MPa、微波处理时间为6 min、加酶量为1.5%和酶解时间为8 h,可制备含木二糖和木三糖的低聚木糖,提取率为43.8%。     

以糖蜜为原料利用双酶法制备低聚果糖

以制糖业的加工副产品糖蜜为原料,利用糖蜜中蔗糖通过双酶法转化开发一种饲料级低聚果糖的加工工艺,以提高糖蜜的附加值及利用率.以果胶酶和果糖基转移酶为复合酶液,通过单因素实验确定的糖蜜酶反应制备低聚果糖的最佳条件为:反应温度55℃、pH 5.5、果胶酶与果糖基转移酶的体积比为20∶1、酶反应时间10 h.在最佳条件下,低聚...     

功能性寡糖调控肠道健康的研究进展

功能性寡糖是不易被肠道吸收,但却能改善肠道健康的一类碳水化合物。近年来,人们关于功能性寡糖的生物活性,尤其是在寡糖对肠道健康的影响方面,开展了广泛地研究。功能性寡糖可通过提高消化酶活性、改善肠道组织及产生乳酸等方式来促进肠道对营养物质和矿物元素的吸收,也可通过调节肠道菌群、改善肠道组织、增加短链脂肪酸的产生等途径来缓解代谢综合症、减轻炎症、增强免疫反应以及改善肠道黏膜屏障等,为肠道提供一个良好的内部环境。本文对功能性寡糖的肠道健康调控作用进行了综述,以期为功能性寡糖的深入研究与应用提供理论依据。     

酶法联合超声技术制备灵芝寡糖及其对乳酸杆菌的增殖作用

为探究酶解联合超声法制备灵芝寡糖的最佳工艺及灵芝寡糖对乳酸杆菌的增殖作用。以灵芝水提物为原料,优化了酶解和超声条件,对比了原料液和酶解联合超声处理后经3000 Da超滤膜处理所得寡糖得率和结构的差异,分析了其对乳酸杆菌的体外增殖作用。结果表明,酶解条件为酶解时间9 h、温度50 ℃、pH5、酶用量1000 U/g底物、超声时间60 min、超声功率480 W时,灵芝寡糖得率最高,为1.76%,比原料液中提高了61.46%。经傅里叶红外光谱分析,灵芝寡糖样品具有典型的β-型糖苷键特征和吡喃环化合物的特征。乳酸杆菌增殖实验表明灵芝寡糖对乳酸杆菌具有良好的增殖效果,且其增殖效果优于灵芝多糖。实验为灵芝寡糖的制备及其应用于功能性食品的开发提供了依据。     

裙带菜功能低聚糖的制备工艺优化

为了实现裙带菜的高值化利用,采用酶解法降解裙带菜多糖制备裙带菜功能低聚糖。采用果胶酶、纤维素酶和植物水解酶,以单酶和混合酶的形式水解裙带菜多糖,以低聚糖得率及低聚糖对副干酪乳杆菌（Lactobacillus paracasei）TYM201增殖效果为指标筛选水解酶,并以低聚糖得率为考察指标,通过单因素试验及响应面试验对低聚糖的制备工艺条件进行优化。结果表明,混合酶的酶解效果优于单酶,且果胶酶-纤维素酶（1∶1）酶解效果最好,低聚糖得率为13.89%,对菌株TYM201增殖作用良好（OD600 nm值为0.18）。裙带菜功能低聚糖的最佳制备工艺参数为：酶解pH值5.9、酶解温度51℃、酶解时间237 min,加酶量0.6%(V/V)。在此优化条件下,裙带菜低聚糖得率为12.43%。     

马尾藻功能低聚糖的制备及酶解工艺优化

为了实现马尾藻功能低聚糖生产的低成本化和高效率化，该实验采用水提醇沉法从干马尾藻中提取马尾藻粗多糖，通过酶解工艺将其降解为马尾藻低聚糖（SPO）。以马尾藻还原糖增量及低聚糖对副干酪乳杆菌（Lactobacillus paracasei）TYM201增殖效果为指标筛选最适水解酶。以还原糖增量为评价指标，在单因素试验基础上，运用Plackett-Burman试验设计筛选出3个影响显著的关键因素——酶底比、酶解温度和酶解pH，再通过最陡爬坡试验和Box-Behnken试验设计优化酶解工艺。结果表明，马尾藻功能性低聚糖的最佳酶解工艺条件为酶解温度54.5 ℃，酶底比7∶1 000，酶解pH值5.46。此优化条件下，马尾藻多糖经酶解后的还原糖增量可以达到21.44%。     

Effect of various conditions on the formation of oligosaccharides in milk treated with beta-galactosidase

Fresh pasteurized milk was inoculated with beta-galactosidase from two different microbial sources at three levels and analyzed for oligosaccharides by high performance liquid chromatography. Five oligosaccharides were observed in the course of hydrolysis. However, only two of these showed measurable increases in concentration. Rate of oligosaccharide formation during hydrolysis was influenced by source and amount of enzymes, reaction time, and temperature. Maximum concentrations of the two oligosaccharides occurred between .5 and 3 d at 7 degrees C and between 1 and 3 d at 1 degrees C, depending on the level of the enzyme used. The higher level of enzyme formed a higher concentration of oligosaccharides than the low level, except at 37 degrees C. After maximum concentration was reached, the two oligosaccharides decreased following hydrolysis, but rate of decrease was dependent upon time, temperature, and enzyme concentration. Hydrolysis of the oligosaccharide was faster at 7 degrees C and at the higher enzyme concentration. Maximum concentration of oligosaccharides was .374 g/100 g milk but was negligible after 7 d, except when the low level of enzyme was used. The total concentration of the oligosaccharides formed in enzyme-treated milk was insignificant.     

Inulin Potential for Enzymatic Obtaining of Prebiotic Oligosaccharides

Oligosaccharides have been marketed since the 80s as low-calorie agents and recently have gained interest in the pharmaceutical and food industry as functional sweeteners and prebiotic enriching population of Bifidobacteria. Currently, they have an approximated value of $200 per kg and recently, inulin has been proposed as a feedstock for production of oligosaccharides through selective hydrolysis by action of endoinulinase. High optimum temperature (60°C) and thermostability are two important criteria that determine suitability of this enzyme for industrial applications as well as enzyme cost, a major limiting factor. Significant reduction in cost can be achieved by employing low-value and abundant inulin-rich plants as Jerusalem artichoke, dahlia, yacon, garlic, and onion, among others. In general, the early harvested tubers of these plants contain a greater amount of highly polymerized sugar fractions, which offer more industrial value than late-harvested tubers or those after storage. Also, development of recombinant microorganisms could be useful to reduce the cost of enzyme technology for large-scale production of oligosaccharides. In the case of fungal inulinases, several studies of cloning and modification have been made to achieve greater efficiency. The present paper reviews inulin from vegetable sources as feedstock for oligosaccharides production through the action of inulinases, the impact of polymerization degree of inulin and its availability, and some strategies to increase oligosaccharide production.     

马铃薯淀粉磷酸寡糖研究进展

磷酸寡糖是指麦芽低聚糖中的某些葡萄糖残基与磷酸根共价连接的一种新型的功能性低聚糖类。除了具有一般低聚糖的生理功能外,还具有促进钙、铁等矿物质吸收的功能。本文对马铃薯淀粉磷酸寡糖的研究历程、结构和功能特性,以及目前存在的问题做了较为详细的阐述,并对磷酸寡糖的开发前景进行展望。     

Production of soya milk containing low flatulence‐causing oligosaccharides in a packed bed reactor using immobilised α‐galactosidase

Peanut α‐galactosidase was immobilised in calcium alginate beads and used to hydrolyse the flatulence‐causing oligosaccharides, raffinose and stachyose, in soya milk in batch and in packed bed reactor with recycle. The immobilised enzyme exhibited a slightly lower activity than the free enzyme. The activity yield of immobilised α‐galactosidase was 75.1% and the immobilisation yield was 82.6%. Batch hydrolysis using immobilised enzyme at 55 °C resulted in 96% reduction in the oligosaccharides after 12 h. For the continuous process, a packed bed reactor with recycle was used. More than 98% of the oligosaccharides were hydrolysed after 6 h of reaction at 55 °C. The immobilised enzyme also proved to be stable up to three repeated hydrolysis reactions.     

酶法制备透明质酸寡糖及其透皮吸收活性研究

为研究透明质酸寡糖的透皮吸收活性,采用透明质酸裂解酶对透明质酸进行酶法降解,制备透明质酸寡糖,通过红外光谱与质谱对透明质酸寡糖进行分析,并对其吸湿性能、体表保湿性能和透皮吸收性能进行评价.结果显示,透明质酸裂解酶酶解制备透明质酸寡糖的最适底物浓度为1％,最适加酶量为3.0 U/mg,酶解制备透明质酸寡糖基本没有基团脱落...     

Biological activities of chitosan and chitooligosaccharides

Chitosan and its oligosaccharides, which are known to possess multiple functional properties, have attracted considerable interest due to their biological activities and potential applications in the food, pharmaceutical, agricultural and environmental industries. Many researchers have focused on chitosan as a potential source of bioactive materials in the past few decades. This review focuses on the biological activities of chitosan and chitooligosaccharides based on our and others’ latest research results, including hypocholesterolemic, antimicrobial, immunostimulating, antitumor and anticancer effects, accelerating calcium and iron absorption, anti-inflammatory, antioxidant and Angiotensin-I-converting enzyme (ACE) inhibitory activities and so on, which are all correlated with their structures and physicochemical properties. The bioactivities summarized here may provide novel insights into the functions of chitosan, its derivatives or oligosaccharides and potentially enable their use as functional-food components and additives.