黑曲霉耐酸性α-淀粉酶的固态发酵条件研究

研究了固态发酵条件对黑曲霉(Aspergillus niger)PZ301合成酸性α-淀粉酶的影响。结果表明,固态发酵最佳培养基组成:麸皮7.0g,葡萄糖0.07g,淀粉0.21g,(NH4)2SO40.07g,起始pH 4.2;最佳培养条件为培养温度35℃,料水比为1∶1,接种量3mL(孢子浓度为107个/mL)。在上述条件下培养72h,酶活力可达19.6IU/g干培养基。另外还测定了PZ301固态发酵中生物量的变化,PZ301菌株的生物量和耐酸性α-淀粉酶在72h时均达到最高,这表明耐酸性α-淀粉酶系同步合成型酶。     

米曲霉固态发酵麻疯树籽饼产中性蛋白酶条件的研究

以实验室筛选出的米曲霉(Aspergillus oryzae)Asp-1为菌种,麻疯树籽饼为发酵主料,采用固态发酵法生产中性蛋白酶.考察了固态发酵培养基液固比、初始pH、接种量等发酵条件,以及麻疯树籽饼中添加麸皮、碳源、氮源对该菌株产酶能力的影响.经单因素和正交实验获得最佳发酵条件为:培养基液固比1:1,初始pH 6,接种量每10 g培养基含有1×108个孢子,培养基中麸皮添加量10%、葡萄糖添加量0.5%、蛋白胨添加量1%.最佳条件下发酵2 d酶活可达3 759.8 U/g.     

少根根霉γ-亚麻酸固态发酵条件的研究

通过He-Ne激光、紫外线和化学诱变剂LiCl复合诱变，获得高产GLA菌株少根根霉RC378，摇瓶培养含油脂量47．8％，GLA含量12．6％。经发酵条件优化得到菌株RC378固态发酵条件，培养基基本配比为∶麸皮∶玉米粉∶菜籽粕∶大米粉＝6∶4∶2∶1，培养基料与水分比例为1∶1．5，在添加2％蔗糖，0．2％NH4NO3，0．4％柠檬酸钠，0．3％ZnSO4的情况下，采用孢子悬液接种，发酵前期（72h)30℃培养，后期（60h）24℃培养基固态发酵干基油脂含量可达9．4％－12．9％，GLA含量可达9．8％－12．6％。     

复合菌种固态发酵豆粕生产蛋白饲料的研究

采用黑曲霉、米曲霉复合菌株固态发酵法生产豆粕饲料.研究了发酵培养基和发酵条件对固态发酵的影响,得到了最佳工艺条件,结果表明:接种总量0.75％,麸皮添加量5％,牛肉膏添加量0.2％,发酵温度30℃,发酵时间43 h,粗蛋白质质量分数可达54.23％,蛋白酶活力达到776.2 U/g.     

黑曲霉固态发酵产生果胶酶条件的优化

以黑曲霉为菌株,以农产品加工副产物为主要物料,采用固态发酵方法生产果胶酶,优化发酵培养基主要物料和培养条件.实验结果表明:培养基的主要物料为麸皮与豆粕,其比例为8:2,加入3.5%的硫酸铵,培养基初始pH自然,250 mL三角瓶中适宜装料量为15 g,料水比为1:1.5,接种量为106个孢子/g干基,在此优化条件下,果胶酶活力可以达到2262 U/g.     

高产类胡萝卜素的蛹虫草固体发酵体系研究

蛹虫草类胡萝卜素是一种水溶性天然色素,具有抗炎、抗氧化、免疫调节等多种功效,在食品工业中具有广泛的应用空间,是一类亟待开发的新型色素。以类胡萝卜素含量为指标,采用谷物类培养基优化3株类胡萝卜素高产菌株的固体发酵培养基,结果表明:菌株CM10的类胡萝卜素产量最高,其最佳培养基配方为小麦73%、麸皮20%和玉米7%。通过两段培养和单因素及响应面试验,确立蛹虫草CM10的最佳固体发酵体系为:基质颗粒度10目,基质初始含水量48%,自然pH,接种量25%,黑暗培养时间12 d,黑暗培养温度22℃,装料量25 g,光照温度25℃和光照时间14 d。此时,类胡萝卜素含量最高,达346μg/g。     

基于响应面法分析菌比和辅料对发酵麸皮多糖含量的影响

本实验旨在以Plackett-Burman设计和响应面法探讨菌种比例和辅料对发酵麸皮中多糖含量的影响,为麸皮深加工利用提供了科学依据。Plackett-Burman实验结果表明,豆粕粉添加量、玉米粉添加量和酿酒酵母接种量三个因素显著(p<0.05)影响发酵产物中多糖含量;进一步利用响应面法建立二次多项数学模型,曲面回归方程拟合性良好。优化得到菌种比例和辅料添加量为:发酵总体系为100%,双菌总接种量10%(酿酒酵母接种量6.73%,枯草芽孢杆菌接种量3.27%),固态培养基由40.23%麸皮、4.66%豆粕粉和5.11%玉米粉组成,料水比1:1。在此优化条件下,发酵麸皮中多糖含量可达55.92 mg/g,与预测值55.15 mg/g相近。     

高地芽孢杆菌的筛选鉴定及其对雪茄烟叶发酵产香的影响

该研究从雪茄烟叶表面筛选具有解磷作用的菌株，结合形态观察和16S r DNA序列分析对筛选出的菌株进行鉴定。以烟叶自然发酵为对照，分别以添加筛选菌株、添加筛选菌株和营养剂的方式进行发酵，分析发酵过程中生物量、无机磷、还原糖和游离总氨基酸含量及致香成分的变化，并对接种量进行优化。结果表明，获得的7株具有解磷作用的菌株，其中菌株Q627解磷作用最好，经鉴定为高地芽孢杆菌(Bacillus altitudinis)。与自然发酵及接种发酵方式相比，接种菌株Q627及添加营养剂的发酵方式解磷效果较好，发酵结束时，其无机磷含量为1.60μg/g，比自然发酵(1.28μg/g)和接种菌株Q627发酵(1.18μg/g)分别提高29%和37%，且生物量、还原糖、总游离氨基酸含量分别为1.20×10⁷ CFU/g、15.01 mg/g、1.44 mg/g；发酵6 d时，其美拉德反应产物、类胡萝卜素降解产物和西柏烷类降解产物含量最高，分别为20.31μg/g、47.57μg/g、47.83μg/g，香气成分总含量为156.18μg/g；确定雪茄烟叶发酵最佳接种量为7.5×10     

绿僵菌Ma83固态发酵几丁质酶和部分酶学性质的初步研究

研究了金龟子绿僵菌MetarhiziumanisopliaeMa83菌株产几丁质酶的固态发酵条件和粗酶液的酶学性质。研究结果显示 ,当以麸皮∶蚕蛹粉为 3∶1作为培养基 ,最适氮源为1%NaNO3,起始pH为 6 5 ,发酵温度为 31℃ ,接种量为 2mL液态种子时酶活力最高。此外 ,添加稻壳对Ma83产几丁质酶有促进作用。该菌株在生长 2d时 ,酶活力达 33 9U /g干培养基。酶的最适反应温度为 5 0℃ ,最适反应 pH为 6 0 ;不同温度保温 1h后 ,酶的半失活温度为 42℃。不同 pH值的缓冲溶液中 (2 5℃ )放置 1h后 ,酶在pH 5 0～ 6 0条件下稳定性最高     

产耐酸陛α-淀粉酶菌株固态发酵条件的优化

对产耐酸性α-淀粉酶黑曲霉菌株AS-Y的固态发酵条件进行了优化。经过单因素实验和正交试验，影响产耐酸性α-淀粉酶的菌株产酶量的主要因素为含水量〉接种量〉附加氮源〉Ca^2＋。固体发酵条件中，水：麸皮为1：1，麸皮量为15g，接种量为4mL，温度为30℃～32℃。发酵培养基中，麸皮：硫酸铵为1：0．05，CaC12为0．01g。在上述最佳的发酵条件下，确定其固体发酵时间为60h～72h，酶活达到286．64U/g。     

Amylase production in solid state fermentation by the thermophilic fungus Thermomyces lanuginosus

The production of extracellular amylase by the thermophilic fungus Thermomyces lanuginosus was studied in solid state fermentation (SSF). Solid substrates such as wheat bran, molasses bran, rice bran, maize meal, millet cereal, wheat flakes, barley bran, crushed maize, corncobs and crushed wheat were studied for enzyme production. Growth on wheat bran gave the highest amylase activity. The maximum enzyme activity obtained was 534 U/g of wheat bran under optimum conditions of an incubation period of 120 h, an incubation temperature of 50 degrees C, an initial moisture content of 90%, a pH of 6.0, an inoculum level of 10% (v/w), a salt solution concentration of 1.5:10 (v/w) and a ratio of substrate weight to flask volume of 1:100 with soluble starch (1% w/w) and peptone (1% w/w) as supplements.     

里氏木霉利用麦糟生产纤维素酶

利用里氏木霉（Ｔｒｉｃｈｏｄｅｒｍａｒｅｓｅｉ）,以啤酒厂的废糟为原料,添加适量麸皮和稻草粉为培养基进行固态发酵,采用固体种曲混合接种,在４８ｈ翻曲,经１４４ｈ发酵后ＦＰＡ酶活达到３５７Ｕ／ｇ。以补加３％麸皮的酒糟水为培养基,调起始ｐＨ６．５培养９２ｈ的液体种子接种,ＦＰＡ酶活为１７８Ｕ／ｇ。     

高效液相色谱法测定糜子中酚酸类化合物

为探索糜子麸皮和糜米中酚酸类物质的成分和含量,采用福林-酚法和高效液相色谱法测定比较糜子麸皮 和糜米中自由酚含量和酚酸类物质的种类。结果表明：不同品种糜子麸皮之间自由酚含量差异不显著,糜米之间自 由酚法差异极其显著（P＜0.01）。同一品种糜子麸皮和糜米之间自由酚含量差异显著（P＜0.05）,糜子麸皮自由 酚含量远高于糜米。赤糜2号麸皮和糜米中自由酚含量最高,麸皮中为159.22 mg没食子酸/100 g,糜米中为47.98 mg 没食子酸/100 g。糜子中检测到的酚酸类物质有绿原酸、丁香酸、香草酸、p-香豆酸、阿魏酸。     

香菇菌丝体液体发酵的研究

利用麸皮浸提液配制发酵培养基,研究了香菇菌丝体发酵培养基对胞外内多糖和菌丝体生物量的影响.结果表明,最适宜培养基配方为麦麸60％、蔗糖1％、MgSO40.15％、KH2PO40.2％.研究了香菇液体菌种发酵过程中菌丝体生物量、pH值、胞外多糖含量的变化,确定了最佳接种量为12％,最佳发酵时间为11d,发酵液的最终pH值在4.2左右.     

不同固态培养基对蛹虫草子实体品质的影响

通过测定不同固态培养基培养蛹虫草子实体的生长情况,虫草素、虫草酸、虫草多糖含量,1,1-二苯基-2-三硝基苯肼（DPPH）自由基清除率及2,2'-联氮-双-3-乙基苯并噻唑啉-6-磺酸（ABTS）自由基清除能力,研究不固态培养基对蛹虫草子实体品质的影响。结果表明,不同固体培养基培养蛹虫草子实体的活性物质与抗氧化活性差异显著（P＜0.05）,其中小米+麦麸培养基培养蛹虫草子实体的生长情况较佳,出芽时间最快,为12 d,子实体最长,为（6.50±0.15） cm,鲜质量最重,为（8.58±0.07） g,其虫草素和虫草酸含量最高,分别为（6.53±0.06） mg/g和（7.66±0.21） mg/g;薏仁米培养基培养蛹虫草子实体虫草多糖含量最高,为（59.07±1.89） mg/g,薏仁米＋麦麸培养基抗氧化活性最强,DPPH自由基清除率和ABTS自由基清除率分别为（66.84±0.77）%、（68.28±0.26）%。     

Antioxidant profiling of native and modified cereal brans

Bran is detached from cereals during roller-milling operations and considered as a byproduct of milling. Bran carries phenolics and antioxidants in appreciable quantities which can be heightened by modification. In the present project, four cereals were under study that is, wheat, barley, millet and sorghum. Bran was separated from cereal grains and was subjected to size reduction that is, fine (1 mm) and coarse (2 mm) and enzymatic modification by using xylanase and cellulase. Total phenolic content (TPC), total flavonoids content (TFC) and phytic acid were determined spectrophotometrically and phenolic acids through HPLC. TPC and TFC were recorded highest in xylanase-treated millet bran (0.304 mg GAE g⁻¹ and 211.42 μg g⁻¹ QE respectively). In vitro antioxidant activity assessed by DPPH and FRAP was found to be highest in coarse millet bran (89.51% inhibition) and native sorghum bran (722.52 μMFeSO4 g⁻¹) respectively. Phytic acid was observed highest in xylanase-treated barley bran (5.80 g per 100 g).     

Single‐cell protein production through microbial conversion of lignocellulosic residue (wheat bran) for animal feed

Agricultural residue (wheat bran) rich in carbohydrates was utilized in the fermentation process to produce microbial biomass. Single‐cell biomass consists of the dried cells of microorganisms, which are used as protein supplements in human food and in animal feed. In the present study, two different microorganisms (Candida utilis and Rhizopus oligosporus) were studied for biomass production. To enhance the nutritional contents of wheat bran, a number of different fermentation parameters (effect of inoculum size, age of inoculum, incubation period, moisture to substrate ratio and incubation temperature) were optimized. Maximum yield was obtained at an inoculum size of 10% (v/w), with the age of the inoculum being a 48 h old culture. A fermentation period of 48 h was found to give the maximum protein yield and viable counts of yeast cells and mould hyphae. The microorganisms showed good growth at 30 °C. After complete optimization of the fermentation parameters, a batch of wheat bran was fermented with C. utilis and R. oligosporus under the optimized conditions, resulting in a maximum crude protein yield of 41.02% compared with the 4.21% crude protein of the non‐fermented wheat bran. Copyright © 2015 The Institute of Brewing & Distilling     

纳豆芽孢杆菌固态发酵小米糠产抗氧化肽工艺优化

为提高小米糠蛋白资源的利用率,为小米糠的深加工提供参考,采用纳豆芽孢杆菌对小米糠进行固态发酵以获得小米糠抗氧化肽。在单因素试验的基础上以小米糠发酵后水提液的总抗氧化能力(total antioxidant capacity,T-AOC)为指标,使用Plackett-Burman试验对发酵条件进行筛选,然后使用响应面法对发酵条件进行优化,并测定优化后小米糠水提液的多肽含量和1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除能力。结果显示最适发酵条件为:小米糠平均粒径0.22 mm(60~80目)、菌液接种量0.4 mL(约108 CFU/mL)、初始pH 6.7、发酵时间26 h、发酵温度35℃。此条件下小米糠固态发酵后提取液的T-AOC实际值为(344.51±8.02)U/g小米糠,多肽提取量为(68.37±0.92)mg/g小米糠,清除DPPH自由基IC50为0.12 mg/mL。该研究表明,小米糠固态发酵条件经过优化后能够获得具有较高抗氧化能力的生物活性肽。     

INCREASED GLUCOAMYLASE PRODUCTION USING AGRICULTURAL BY-PRODUCTS

ABSTRACT Media prepared from agricultural by-products including malt, wheat bran, corn steep liquor and soybean flour, were found to be an excellent substrate for proliferation of Aspergillus niger #57. Glucoamylase yields obtained using various combinations of the above materials were ten to fifteen times higher than those obtained uisng semi-synthetic media. A medium comprising 10%wheat bran extract and 8% defatted soybean flour gave the highest enzyme yield of 42 IU/ml as compared with a yield of 2.8 IU/ml obtained using optimal concentrations of glucose and peptone.