利用发酵促进剂提高红酵母β-胡萝卜素产率

为提高红酵母生物合成β-胡萝卜素的产量,分别研究了几种添加物对发酵过程的促进效应。试验结果表明:分别添加硫胺素、核黄素、大豆油和番茄汁可以显著促进红酵母合成β-胡萝卜素。当按单因素试验确定的最优添加量联合添加硫胺素1.5mg/L、核黄素3mg/L、大豆油5mg/L、番茄汁6mg/L时,试验证实β-胡萝卜素发酵产率可比对照提高80%以上,值得进一步研究。     

阿舒假囊酵母摇瓶分批补料发酵产核黄素的研究

利用摇瓶分批补料培养模式考察了补料基质对核黄素合成的影响.首先考察了葡萄糖补加浓度对阿舒假囊酵母菌体生长和核黄素合成的影响,结果表明,葡萄糖的补加对阿舒假囊酵母的菌体生长具有促进作用,但是当葡萄糖的补加浓度超过0.5g/100mL发酵液时,会对核黄素的合成产生严重的阻遏或抑制效应.在此基础上,考察了补加不同碳源对核黄素发酵的影响,结果显示,补加1.0g/100mL发酵液的蔗糖或麦芽糖虽然均利于菌体生长,但同样会对核黄素的合成具有负作用.最后考察氮源的补加对阿舒假囊酵母发酵的影响,结果表明,补加酵母膏和玉米浆能显著促进菌体的生长,且二者最终的核黄素合成量分别为1582.1mg/L和1816.77mg/L,均明显高于不补加任何氮源实验方案下的1135.48mg/L.     

添加剂及金属离子对类胡萝卜素产率的影响

本文研究了番茄酱、花生油及几种金属离子对粘红酵母发酵产类胡萝卜素的影响,实验表明番茄酱和花生油两种添加剂均对类胡萝卜素的产量有较明显的影响,当添加量分别为4.5g/L和1.0ml/100ml时,类胡萝卜素产量分别比对照组提高了24.75%和13.1%。通过均匀设计试验从六种离子中选出最佳的金属离子组合为K2SO4 1%、MgSO4·7H2O 0.0476%、CuSO4·5H2O 0.00449%,得到的类胡萝卜素产量比起对照组提高了17.03%。     

海洋红酵母产类胡萝卜素的研究

从海洋中筛选出1株产类胡萝卜素能力较强的红酵母RY-8。研究了不同碳源、氮源、装液量和pH值对菌株RY-8生物量和产类胡萝卜素的影响，并通过正交试验优化其产类胡萝卜素的发酵条件。结果表明，红酵母菌株RY-8产类胡萝卜素的最佳发酵条件为：葡萄糖25g/L，酵母膏10g／L，装液量60mL/250mL，pH值6．0。在此优化条件下，红酵母RY-8的生物量和类胡萝卜素产量分别为48．8g／L和4．76mg／L，依次比初始产量提高了20．8％和38．4％。     

高产类胡萝卜素红酵母的筛选及其发酵条件

通过对数株红酵母培养后发酵液中菌体生物量及类胡萝卜素含量的测定比较,从中选出了1株产类胡萝卜素能力较强的红酵母RY-98;研究了该菌株产类胡萝卜素的最适碳源和氮源,并对其主要营养与环境条件进行了选择及优化,获得了最佳发酵条件葡萄糖40g/L、(NH     

黏红酵母高静水压诱变及其β-胡萝卜素发酵培养基的优化

利用300MPa的高静水压处理黏红酵母(Rhodotorula glutinis)RY06菌株10min,获得一株突变株RY06-27,其β-胡萝卜素产量从原来的6.30mg/L增加到9.64mg/L,提高了53%。通过响应面分析法优化发酵培养基,可使该突变株β-胡萝卜素产量达13.43mg/L,其优化培养基组成为酵母膏4.23g/L、接种量30mL/L、番茄汁2.5mL/L、培养基装量40mL/250mL、花生油0.5mL/L、pH6.7、葡萄糖12.11g/L、硫酸铵5g/L。     

桑葚果酒分批发酵动力学研究

以桑葚汁为原料,探讨果酒发酵过程中菌体生长、产物生成和底物消耗变化规律,利用Logistic模型方程拟合菌体生长、产物生成、基质消耗曲线,建立发酵动力学模型。结果表明,当发酵液初始含糖量为200g/L时,接种5%活化酵母,28℃发酵100h后,残糖含量降为3.86g/L,酵母数量增长为2.83×108 CFU/mL,乙醇含量达到9.01%,菌体生长、产物生成、基质消耗的动力学模型拟合度良好,模型R2分别为0.974,0.988,0.991,模型能较好地反映和预测桑葚果酒发酵变化的过程。     

红酵母生产类胡萝卜素5L流加发酵的动力学研究

在前期三角瓶发酵培养的基础上,研究了利用红酵母生产类胡萝卜素在5L发酵罐中的培养.比较了不同的补糖方式、不同pH及不同溶氧条件下红酵母生物量、类胡萝卜素含量和类胡萝卜素产量,结果表明,对于三种条件过高或过低的值都不利于类胡萝卜素产量的提高.最终得出最佳条件应为:总糖浓度80g/L,并且糖的补给方式应为流加,发酵过程中糖浓度应保持在1020g/L之间,酵母粉20g/L,pH为6.0,DO值维持在15%25%之间.为了更好的掌握微生物生长和类胡萝卜素产生的动态过程,利用MATLAB软件对发酵过程进行研究,实验数据采用三次实验结果的平均值,建立了红酵母生长动力学模型和类胡萝卜素形成的动力学模型.比较拟合值和实验值表明拟和模型能较好反映类胡萝卜素分批发酵过程.     

1 株类胡萝卜素产生菌的鉴定及其发酵培养基的优化

利用形态学、生理生化和rDNA-ITS序列分析相结合的方法鉴定1 株产类胡萝卜素的菌株K-1,采用比色法测定其生长和所产类胡萝卜素的稳定性,借助单因素试验和正交试验优化K-1菌株的发酵条件。结果表明,菌株K-1为胶红酵母（Rhodotorula mucilaginosa）,最适生长温度30?℃,生长pH值范围2～7;含有红酵母烯,所产色素的基本稳定性良好,但高温（＞60?℃）、强光和添加氧化剂H2O2可使其稳定性下降。菌株K-1产类胡萝卜素的最适发酵条件为20?g/L葡萄糖、20?g/L?(NH4)2SO4、2?g/L无水CaCl2、5?g/L柠檬酸三钠（培养温度30?℃、接种量10%、摇床转速150?r/min、装瓶量50?mL/250?mL、初始pH?5.5、培养5?d）;优化条件下类胡萝卜素产量达（180.14±2.45）μg/g（干菌体）。研究表明,菌株K-1具有高产类胡萝卜素的潜能,色素稳定性良好,可为微生物类胡萝卜素的发酵生产提供菌种资源。     

红酵母RY-08产类胡萝卜素的发酵条件研究

研究不同碳源和氮源对红酵母RY-08产类胡萝卜素的影响,并用正交试验对碳源、氮源、装液量及发酵时间进行优化。结果表明在葡萄糖40 g/L,蛋白胨20 g/L,装液量30 mL/250 mL,发酵时间72 h的发酵条件下其生物量、类胡萝卜素含量和产量分别达到19.7 g/L,418.6μg/g,8.2 mg/L。     

某些添加物对红酵母生长及类胡萝卜素合成的影响

研究了在培养基中添加蕃茄汁、花生油、V     

放射型根瘤菌辅酶Q_(10)发酵助剂的研究

研究了几种促进剂和前体对放射型根瘤菌细胞生长及其辅酶Q10发酵的影响,结果表明,在培养基中适量添加番茄汁、胡萝卜汁、蛋氨酸、VB1和对羟基苯甲酸均可明显提高辅酶Q10的产量。在所试浓度范围内,VB1、胡萝卜汁和蛋氨酸3种添加物最高可使辅酶Q10产量比对照组分别提高25%、18%和13%。     

五种添加剂对异养小球藻生产叶黄素的影响

研究了番茄汁、缬氨酸、亮氨酸、大豆油和乙醇五种添加剂对异养小球藻C .protothecoides CS-41生物量和合成叶黄素的影响,发现番茄汁和亮氨酸对异养小球藻积累叶黄素具有更显著的促进作用,其中番茄汁在最适添加量下(3 mL/L)最高生物量浓度达到10. 04g,L,叶黄素含量和产量分别达到2. 18mg/g和21. 89mg/L,比对照显著提高(P<0. 05).     

Physicochemical parameters that influence carotenoids bioaccessibility from a tomato juice

In vitro digestion models have been developed to estimate carotenoid bioavailability but most do not consider that their diffusion from fruit matrix to the lipid phase of the bolus could be a limiting step. Therefore we designed a model in which tomato juice is mixed with oil or oil/water emulsions, and the carotenoids diffusing to oil are measured by spectrometry. Temperature, pH and tomato juice/peanut oil ratio were evaluated for their influence on carotenoid diffusion. When oil/tomato ratio was between 0.11 and 1, extraction of lycopene was limited by the saturation of the oil phase. With a large excess of oil, diffusion was also limited, as only 31 ± 1% of lycopene could be extracted from the juice. Diffusion did not vary significantly with pH but doubled when temperature rose from 10 °C to 37 °C.     

Optimization of carotenoids by <Emphasis Type="Italic">Rhodotorula glutinis</Emphasis>

Response surface methodology was applied to maximize the yield and productivity of carotenoids by Rhodotorula glutinis strain 1151 using supplemented tomato waste based medium. Higher concentration of tomato waste extract and yeast extract favored the production of carotenoids. In contrast to carotenogenesis higher concentration of yeast extract negatively affected the formation of biomass whereas higher amount of glucose in the medium favored biomass indicating that carotenogenesis is not correlated to biomass. The optimal concentration of medium components for maximum total carotenoids and corresponding biomass production as obtained from model were calculated to be as 660 mL/L, 1.5, 4.5, 7.4, and 10 g/L for tomato extract, malt extract, yeast extract, peptone, and glucose, respectively.     

Optimization of beta-carotene production by Rhodotorula glutinis using high hydrostatic pressure and response surface methodology

ABSTRACT:  Rhodotorula glutinis RG6 was treated by high hydrostatic pressure (HHP) of 300 MPa for 15 min for improving its ability of β-carotene production. After the treatments of 5 repeated cycles, the mutant strain RG6p was obtained, β-carotene production of which reached 10.01 mg/L, increased by 57.89% compared with 6.34 mg/L from parent strain RG6. To optimize the medium for β-carotene fermentation by mutant RG6p, a response surface methodology (RSM) approach was used in conjunction with a factorial design and a central composite design, and the maximum yield of β-carotene (13.43 mg/L), an increase of 34.17% compared to the control, was obtained at a pH 6.7 with an optimum medium (40 mL/250 mL) of yeast extract (4.23 g/L), glucose (12.11 g/L), inoculum (30 mL/L), tomato extract (2.5 mL/L), peanut oil (0.5 mL/L), and (NH₄)₂SO₄ (5 g/L).     

锁掷酵母与海洋红酵母的营养成分分析

研究了锁掷酵母与海洋红酵母中的类胡萝卜素,氨基酸、脂肪酸组成。锁掷酵母与海洋红酵母中的总类胡萝卜素含量分别为21.42 mg/L,8.02 mg/L。锁掷酵母中含有较多的β-胡萝卜素,而海洋红酵母中以红酵母烯为主。锁掷酵母中含有的β-胡萝卜素以全反式结构为主,全反式结构占总β-胡萝卜素的60%左右,顺式结构主要有13-顺和9-顺β-胡萝卜素。锁掷酵母和海洋红酵母中的蛋白质中均含有常见的20种氨基酸,不饱和脂肪酸占总脂肪酸的比例分别为74%和76%。文中对锁掷酵母与海洋红酵母中含有的类胡萝卜素、蛋白质和脂肪酸进行了比较分析,为锁掷酵母在饲料行业的深入应用奠定了基础。     

Solid-state fermentation for recovery of carotenoids from tomato waste

Tomato waste is an excellent source of nutrients, micronutrients, and bioactive compounds. Some extraction technologies have been used to recover these pigments for their proven biological activities. In this study, solid-state fermentation with Aspergillus niger GH1 was used as a bioprocess for carotenoid extraction and recovery in tomato waste. The chemical composition was evaluated, in addition to the viability of the tomato waste as a solid-fermentation substrate. The results showed that at 70% humidity, pH 4.0, 30 °C, 1 × 10⁶ spores/g of inoculum concentration, and 36 h of fermentation gave the optimal yield. A biomass/carotenoids ratio of 0.164 mg/L of total carotenoids was realized. The number of carotenoids extracted from tomato waste was improved from 0.062 mg/L from zero hours of fermentation to 0.164 mg/L of total carotenoids after 36 h of fermentation. Solid-state fermentation with Aspergillus niger GH1 was a viable approach to enhance the extraction and recovery of carotenoids.