Val bean (Lablab purpureus L.) proteins: composition and biochemical properties

Val bean (Lablab purpureus L.) proteins were fractionated using the Osborne protein fractionation scheme and biochemically characterized. The seed flour contained 302 g kg^?1 protein (micro‐Kjeldahl N × 6.25) on a dry weight basis. Albumin, globulin, prolamin, and glutelin accounted for 22.8%, 45.1%, 1.8% and 30.3%, respectively, of the total soluble seed proteins. Among the solvents tested, 0.1 mol L^?1 aqueous NaOH was the most effective protein solubilizer. Isoelectric focusing indicated the seed proteins to be predominantly acidic (pI range was ～4–7). Val globulin is a glycoprotein composed of at least three polypeptides in the molecular mass range 51–64 kDa. Albumin fraction had the highest trypsin inhibitory activity, while the globulin fraction registered the highest hemagglutinating activity. Sulfur amino acids were the first limiting amino acids in the total seed proteins. The proportion of essential to total [E/T(%)] amino acids for the bean flour was 36.97%. Among the protein fractions, glutelin fraction had the highest E/T (42.86%) followed by albumin (41.57%), globulin (39.87%), and prolamin (39.15%). Native globulin, although resistant to pepsin, was effectively digested in vitro upon moist heat (100 °C, 30 min) denaturation. Copyright © 2007 Society of Chemical Industry     

藤本豆多肽对小鼠免疫调节作用的影响

研究藤本豆多肽对正常小鼠和免疫抑制小鼠免疫功能的调节作用。分别以50、100、150 mg/kg剂量的藤本豆多肽给正常小鼠和免疫抑制小鼠灌胃,对照组灌胃等量的生理盐水,每天给药1次,持续10 d后,通过小鼠胸腺系数、脾系数、小鼠碳粒廓清实验、Con A诱导小鼠脾淋巴细胞转化实验、血清溶血素测定及白介素-2水平来观察藤本豆多肽的免疫调节作用。实验结果表明,与对照组比较,藤本豆多肽中、高剂量组可显著提高正常小鼠的胸腺系数、脾系数、校正碳廓清指数、脾淋巴细胞转化指数、血清溶血素含量及白介素-2的水平;藤本豆多肽对免疫抑制小鼠的免疫指标均有显著提高。因此,藤本豆多肽具有一定的免疫调节作用。     

红曲霉产蛋白酶特性研究

通过对红曲蛋白酶活力的测定初步研究了红曲蛋白酶的特性。实验表明，红曲霉分泌蛋白酶的旺盛期在培养的第4d～6d。红曲蛋白酶的最适反应pH4．0～8．0，在pH5．0～6．0有较好的稳定性。红曲蛋白酶的最适反应温度在35℃-45℃，40℃时酶活力最大。红曲蛋白酶在35℃-40℃有较好的热稳定性。0．5％硫酸铜和0．5％醋酸铅对红曲蛋白酶有抑制作用，0．5％氯化钠对红曲蛋白酶则有激活作用。     

红曲霉产淀粉酶特性研究

通过对红曲淀粉酶活力的测定初步研究了红曲淀粉酶的特性。实验表明，淀粉酶分泌的旺盛期在培养的第4d-7d，红曲淀粉酶的最适反应温度55℃～65℃，在45℃～70℃有较好的热稳定性。最适反应pH5．0-6．0，在pH4．0～7．0有较好的稳定性。0.5％的Pb（NO3）2、CuSO4溶液对红曲淀粉酶有抑制作用，而0．5％的MgSO4、CaCl2、NaCl溶液对红曲淀粉酶有激活作用。     

一株紫色红曲霉菌强化制曲的工艺优化

红曲霉菌的代谢产物和酯化酶等对促进白酒固态发酵过程中的风味和品质提高具有重要意义。为制备适合白酒酿造生产的酯化红曲,该研究对红曲霉菌进行液体培养,再分别以大米、麸皮及混合料等为原料进行纯种培养,选取种子液添加量、培养温度、培养时间和曲料含水率等作为影响因素,制备高酯化力的酯化红曲。结果表明,混合料明显优于大米或麸皮等单独作为原料制备酯化红曲,在培养温度35 ℃、培养时间3 d、曲料含水率55%、乳酸添加量4‰条件下,混合料成品酯化红曲的酯化力为716 mg/100 mL,糖化力为1 065 mg/（g·h）,发酵力为2.01 g/（0.5 g·72 h）,表明该菌株制备的酯化红曲具有较高的应用价值。     

Effect of selected Hofmeister anions on functional properties of protein isolate prepared from lablab seeds (Lablab purpureus)

Effects of selected Hofmeister anions, namely Na₂SO₄, NaCl, NaBr, NaI, NaClO₄ and NaSCN, on the functional properties of a protein isolate prepared from lablab seeds (Lablab purpureus) were investigated. The results of water absorption capacity indicated that highest water absorption was recorded in solutions of Na₂SO₄, and the lowest in NaSCN solutions. Reduction in water absorption capacity followed the Hofmeister series in the order Na₂SO₄ > NaCl > NaBr, NaI > NaClO₄ > NaSCN. Protein solutions prepared in chaotropic (NaI, NaClO₄, NaSCN) salts had better foam capacity, foam stability, emulsifying activity and emulsion stability than solutions prepared with kosmotropic salts (Na₂SO₄, NaCl, NaBr). The results also indicate that increase in foam capacity and stability followed the Hofmeister series in the order Na₂SO₄ < NaCl < NaBr, NaI < NaClO₄ < NaSCN. When least gelation concentration (LGC) was used as the index of gelation capacity, at various salts concentrations, the lowest LGC were observed in NaSCN and the highest LGC in protein solutions prepared with Na₂SO₄. Copyright © 2005 Society of Chemical Industry     

红曲发酵过程中杂菌污染原因分析

目的查找红曲霉菌发酵过程中出现大面积污染造成发酵产量、含量严重下降的原因。方法随机对照分组实验,对实验数据结果作对比分析判断。结果由菌种造成的污染率约为4.31%;由接种操作造成的污染率约为1.76%。结论菌种不纯、接种操作不规范是造成污染的主要原因。     

不同诱变方法对紫红曲霉产红色素的影响

比较了微波、超声波、氯化锂3种不同诱变方法单独和复合诱变对纯种紫红曲霉产红曲色素的影响.结果表明复合诱变比单一诱变效果好,其中超声波诱变35min、微波20s、氯化锂浓度为1.4‰时复合诱变得到的1株菌,其发酵液色价由原始菌株的3.02u/mL提高到了3.86u/mL,相对于原始菌株增加了27.8%.     

Production and antioxidant activity of alcoholic beverages made from various cereal grains using Monascus purpureus NBRC 5965

Monascus sp., which produces red pigments, has been utilized for brewing red alcoholic beverages and fermented foods in China and Okinawa, Japan. Novel red alcoholic beverages with antioxidant activity were made from cereal grains of various colours utilizing the saccharifying activity of Monascus purpureus NBRC 5965. The alcoholic beverage made from black rice and beni koji prepared with M. purpureus NBRC 5965 showed a deep red colour, and the DPPH radical scavenging activity of the alcoholic beverage made from black rice and beni koji was around a 3300 µm Trolox equivalent/mL‐beverage. The antioxidant activity of this alcoholic beverage is thought to be a result of the combination of Monascus pigments and black rice anthocyanin. The DPPH radical scavenging activity and inhibitory activity of lipid peroxidation of an alcoholic beverage made with beni koji were higher than those of an alcoholic beverage made with ki koji prepared with Aspergillus oryzae. Copyright © 2016 The Institute of Brewing & Distilling     

红曲霉菌微胶囊化培养

采用NaCS PDMDAAC微胶囊对红曲霉菌进行了固定化培养试验 ,在进行连续 6批的培养中发现 ,红曲霉菌可以很好地在NaCS PDMDAAC微胶囊生长和产红曲色素。与游离培养细胞的比较表明 ,微囊化培养的糖耗时间会远远少于游离培养 ,红曲色素的浓度在前 3批略低于游离培养 ,一但达到稳定后 ,就会高于游离培养。同时也表明 ,微囊化培养时红曲霉菌的浓度远远大于游离培养。     

藤本豆豆荚总黄酮对小鼠免疫功能的影响

研究藤本豆豆荚总黄酮对正常小鼠免疫功能及体内抗氧化活性的影响。以小鼠免疫器官系数、脾淋巴细胞增殖活性、巨噬细胞吞噬能力、细胞因子水平、血清SOD、GSH-Px和MDA为指标评价藤本豆豆荚总黄酮的免疫功能和体内抗氧化活性。结果表明,与阴性对照组比较,灌胃给予正常小鼠藤本豆豆荚总黄酮30d后,小鼠胸腺系数和脾脏系数分别增加12.34%和8.67%,小鼠脾脏淋巴细胞的增殖活性和巨噬细胞的吞噬能力分别增加114.68%和27.16%,小鼠血清IFN-γ、AKP、SOD和GSH-Px的活性分别提高8.25%,82.52%,10.47%,12.16%,血清MDA水平降低32.97%。藤本豆豆荚总黄酮具有增强正常小鼠免疫功能和体内抗氧化活性的作用。     

紫色红曲霉液态发酵产糖化酶的工艺研究

通过培养基和发酵条件的优化提高紫色红曲霉G6液态发酵产糖化酶活力。研究接种菌龄、碳源、氮源、金属离子、培养基初始pH、接种量、装液量、摇床转速以及温度等对产酶的影响。结果表明,最佳培养基配方（w/v）为大米粉8%,蛋白胨1%,KCl0.1%,ZnSO₄0.01%,FeSO₄0.005%,MnSO40.015%,培养基初始pH为4.0;最适发酵条件:装液量50mL/250mL,转速150r/min,温度32℃,接种量12%（v/v）;在此条件下发酵10d,糖化酶活力为1652.36U/mL比优化前（109.54U/mL）提高了14.08倍。      

Fermentation of Monascus purpureus on Bacterial Cellulose-nata and the Color Stability of Monascus-nata Complex

Nata, a bacterial cellulose produced by Acetobacter aceti ssp. xylinum , was colored by means of fermentation with Monascus purpureus. Scanning electron microscopy (SEM) observations showed that the Monascus mycelium could grow through the cellulose network of nata. Rice powder as a major carbon source and monosodium glutamate (MSG) as a nitrogen source gave an appealing coloration after 12 d of fermentation at 30 °C. Compared to dyed nata, the color of the Monascus -nata complex had better resistance to washing, heat, freezing, acidification, and alkalization. A 66.1% decolorization was found under irradiation with 366 nm ultraviolet light after 36 h. The Monascus -nata complex has the potential to be a new vegetarian foodstuff.     

紫色红曲霉FBKL3.0018产酯化酶的酶学性质研究

以从紫色红曲霉FBKL3.0018中固态发酵得到的粗酶制剂为研究对象,对该菌株的酯化酶酶学性质进行了较系统的研究。通过单因素实验确定该酶最适温度为40 ℃,在30 ℃条件下稳定性较好,最适pH值为6.5,在pH5.5～7.5条件下稳定性好。Fe2+、Na+、Mn2+、Mg2+、Li+、Zn2+对酯化酶酶活力有抑制作用,Ca2+在低浓度时有促进作用,高浓度时有抑制作用。K+对酯化酶酶活力有促进作用,并且随着K+浓度的升高,促进作用逐渐增强。吐温-80、十二烷基硫酸钠（SDS）、聚乙二醇6000、阿拉伯胶4种表面活性剂对酯化酶酶活力都有抑制作用。另外,甲醇和乙醇对该酯化酶酶活力有抑制作用,甲酸、乙酸、乳酸对酯化酶酶活力有促进作用。乙酸乙酯在低浓度时对酯化酶酶活力有抑制作用,含量为30%时反而有促进酶活力的作用。酯化酶最大反应速度Vmax为0.016 mol/（L·min）,米氏常数Km为0.015 4 mol/L。     

红曲霉发酵高温豆粕高产可溶性多肽

通过利用红曲霉发酵高温豆粕产生可溶性多肽,确定菌株对变性蛋白质有一定的分解作用;并采用紫外诱变红曲霉,经初筛和复筛,最终筛选出能高产可溶性多肽的菌株。结果表明：红曲霉发酵可分解高温豆粕中的蛋白质,并且产生分子质量介于7.8～20.1 kD的可溶性多肽。发酵120 h可产生（13.41±0.20） mg/mL的可溶性多肽,是原豆粕的3.60 倍。15 W紫外线灯35 cm处,搅拌条件下照射50 s,红曲霉的致死率为（82.70±2.20）%。在此诱变条件下得到一株高产可溶性多肽的突变红曲霉0501100菌株。该菌株在发酵豆粕96 h时产生的可溶性多肽含量达到（17.20±0.18） mg/mL,是原菌株在同等发酵时间条件下产生可溶性多肽的1.47 倍,是原豆粕的4.61 倍,缩短了发酵时间并且有较好的遗传稳定性。     

红曲霉液态法生产红色素发酵条件的优化

研究了菌株紫红曲霉No．1-18-54液态发酵产红色素的发酵条件。结果表明，适宜的发酵条件为起始pH6．0，摇瓶装料量20mL／250mL三角瓶，接菌种龄48h，接种量10％（v／v），发酵温度30℃，摇床转速180r／min，发酵周期132h。实验研究还发现在发酵培养基中添加0．2％味精有利于红色素的生成，平均色价为66．7U／mL。     

紫色红曲霉中新型酯酶ESM1的纯化及其酶学特性研究

该研究以白酒大曲中筛选出的一株高产酯酶菌株HQ为研究对象,采用分子生物学对其进行菌种鉴定。通过硫酸铵二级沉淀、丁基琼脂糖凝胶柱和Superdex G-200柱对其所产的酯酶进行纯化,并进行N-端序列、质谱和酶学性质分析。结果表明,菌株HQ被鉴定为紫红曲霉（Monascus purpureus）,经纯化获得一个分子质量为60 kDa的酯酶,命名为ESM1。酯酶ESM1具有一段酸性蛋白酶的肽段序列,最适温度为60 ℃、最适pH值为7.0,在温度为50 ℃的环境和中性环境中表现出良好的稳定性。Zn2+、Ca2+和Na+对ESM1有促进作用,其中Zn2+促进作用最高,Cu2+、Mg2+、Fe2+和Mn2+有抑制作用,其中Cu2+的抑制作用最强。     

紫红曲霉发酵大米淀粉糖化酶的制备

对紫红曲霉液体发酵生产糖化酶的大米淀粉培养基进行优化,研究了NaNO3、大米淀粉、KH2PO4浓度对紫色红曲霉产糖化酶的影响,通过三因素实验确立了产糖化酶培养基三种主要成分的最优条件：NaNO3 0.6g/100mL,大米淀粉3g/100L,KH2PO4 0.5g/100mL.在250mL三角瓶装50mL培养基,接种量4%,培养时间120h,在上述条件下生物量干重0.3392g,发酵液糖化酶活166.95U/mL,比初始条件下高出2.4倍.     

不同营养元素对紫色红曲霉液态发酵产酯化酶的影响初探

以紫色红曲霉（Monascus purpureus）FBKL3.0018为研究对象,发酵产酯化酶的酶活力为考察指标,初步探究了维生素、氨基 酸及其他营养元素等对紫色红曲霉FBKL3.0018产酯化酶的影响。 结果表明,在发酵培养基中分别添加0.20%维生素B2、0.3% L-谷氨酸、 0.7% D-半乳糖对菌株产酯化酶的能力较好,其中添加0.7% D-半乳糖对产酯化酶起显著促进作用,酯化酶酶活最大值为919.12 U/mL, 而蔗糖对酯化酶酶产量影响最小,但对红曲霉生物量产量起积极作用,最大生物量为68.94 mg/mL。 结果显示,酯化酶酶活与相应的 生物量积累量不呈正相关。