1株高产多糖红曲霉菌株的分离鉴定及生物学特性研究

从市售红曲米和红腐乳中分离纯化得到56株红曲霉菌株,通过摇瓶发酵试验筛选出1株胞外多糖产量为4.73 g/L的红曲霉菌株M-6;依据形态特征、生理生化特征和ITS序列将菌株M-6鉴定为红色红曲霉（Monascus rubber）。并对其部分生物学特性进行了研究。     

红曲霉属的一个新种

本文报告了从安徽省望江酒厂大曲中分离到的红曲霉属(Monascus van Tieghem)的一个新种——橙色红曲霉 Monascus aurantiacus Li sp. Nov. AS 3.4384。 该菌株不仅具有很强的糖化酶活力,而且在形态上与芝曲霉属的已知种有较明显的差异。对这个新的分类单位作了汉文和拉丁文描述,并讨论了定为新种的理由。     

云南省可培养丝孢真菌资源的调查研究Ⅰ*

作者于1992年在云南省实地考察,历时60天。在此期间共采集了土壤样品和其他材料共414号,并从这些基物中分离到大量菌株,研究结果将陆续整理并发表。除新种、罕见种和我国新记录种进行详细描述并附图外,其他物种均以名录形式予以报道。本文报道曲霉属（Aspergillus）的8个分类单位：帚状曲霉,烟色曲霉原变种,烟色曲霉椭孢变种,绿垂曲霉,棒曲霉,矮棒曲霉,烟束曲霉和爪甲曲霉。     

红曲霉T-DNA插入突变库中色素突变子的筛选

红曲霉（Monascus purpureus）是我国重要的传统食用和药用微生物,能分泌红曲色素、莫纳卡琳（Mo-nacolin K）、γ-氨基丁酸、麦角固醇等物质,被广泛用于生产食品发酵剂、食品着色剂、保健食品和药品等,在我国有上千年的应用历史。本实验以根癌农杆菌（Agrobacterriumtum efaciens）介导的红曲霉突变体库中754株突变子菌株为材料,通过乙醇提取法筛选出了9株产红曲色素发生显著变化的色素突变子,其中S50在505 nm波长处的色价降为原始菌株S的0.12倍,几乎变为白化株。300~600 nm波长下UV-VIS扫描图谱特征显示,色素突变子不仅色价发生了变化,而且吸收波长、吸收峰值也发生了不同程度的变化。最后,对色素突变子菌落形态、显微结构、潮霉素抗性、遗传稳定性以及产桔霉素能力等进行分析,为研究红曲霉产色素相关基因奠定了基础。     

不产桔霉素的红曲霉菌种深层发酵生产莫纳可林K

对三株在YES培养基中不产桔霉素的红曲霉菌种,在摇瓶中研究了它们液体发酵生产莫纳可林K的情况。在大米粉培养基中,红色红曲霉不产莫纳可林K,但是紫色红曲霉和烟灰色红曲霉均能产莫纳可林K,前者产量高于后者。在葡萄糖．甘油培养基中,后两者的产量均很低,但是如果在该培养基中添加酵母膏,紫色红曲霉能产生较为可观的莫纳可林K。在2L的发酵罐中,利用添加了酵母膏的葡萄糖-甘油培养基,紫色红曲霉在第13d的莫纳可林K产量可达104mg/L,培养过程中无桔霉素产生。     

红光对红曲霉生长及次级代谢产物的影响

光照作为重要的环境因子之一,对包括真菌在内的多种生物的生长及生理过程起着重要作用.研究发现,红色单色光对平板培养的红曲霉(Monascus M10)菌落形态有明显的影响;在液态发酵时,红光在发酵初期可促进红曲霉的生长并促进其提前进入色素合成期,但对其生物量无明显影响;红光培养与黑暗培养对照相比,其发酵液、菌丝及单位菌丝中产生的色素都有明显提高,并在一定程度上降低了桔霉素的产量.     

红色红曲霉Mr-1的次级代谢产物生物活性成分分析

【背景】红曲霉(Monascus)是一种重要的药食同源性真菌,其自身产生的次级代谢产物具有多种生理活性功能,然而红曲霉中的生物活性成分却鲜有报道。利用红曲霉发酵液进行药效物质成分追溯,对了解红曲霉药效物质基础具有十分重要的意义。【目的】对红色红曲霉(M.ruber)Mr-1次级代谢产物中的生物活性成分和生物学功能进行研究。【方法】采用硅胶柱、SephadexLH-20凝胶柱等色谱技术对活性成分进行分离纯化,通过核磁共振和高分辨质谱技术对化合物结构进行解析;对鉴定的化合物进行体外抗氧化、抑菌和酶活性测定。【结果】从红色红曲霉Mr-1次级代谢产物中分离得到4个活性化合物,鉴定为3个黄酮类化合物Luteolin(1)、Hesperetin(2)、Glycitein(3)和1个萜类化合物Ursolic acid(4)。化合物1、2、4为首次从红曲菌科中分离得到。在抗氧化试验中,化合物1对ABTS⁺、DPPH和OH^-自由基具有较强的清除能力,IC₅₀分别为13.36、8.74和32.75μg/mL;在抑菌试验中,化合物4对金黄色葡萄球菌(Staphylococcus aureus)和李斯特菌(Listeria monocytogenes)表现出中等强度的抑菌能力,抑菌圈直径分别为13.4 mm和11.9 mm;在α-葡萄糖苷酶抑制活性试验中,化合物4表现出很强的抑制能力,IC₅₀为21.34μg/mL。【结论】红色红曲霉Mr-1是宝贵的微生物种质资源,其产生的次级代谢产物生物活性成分多样,具有开发成功能性食品原料的潜能。     

一株高产洛伐他汀红曲霉的筛选与液态发酵条件优化

【背景】洛伐他汀(lovastatin)是红曲霉的次生代谢产物,是重要的临床用降血脂药物。在液态发酵条件下,红曲霉的洛伐他汀产量较低,难以满足工业化生产的要求。【目的】筛选获得一株高产洛伐他汀的红曲霉株,并通过优化液态发酵条件提高洛伐他汀的产量。【方法】从红曲米中筛选获得一株高产洛伐他汀的红曲霉株,依据形态学特征、生理生化特性及18S rRNA基因序列分析对分离菌株进行鉴定;通过响应面法对其产洛伐他汀的液态发酵条件进行优化。【结果】获得一株产洛伐他汀的紫红曲霉(Monascus purpureus M4),该菌在甘油57.80g/L、酵母浸粉5.52 g/L、接种量为6.90%条件下,洛伐他汀产量(173.60 mg/L)较优化前提高了4.8倍。【结论】菌株M4产洛伐他汀最优液态发酵条件的建立,为洛伐他汀的大规模生产及该菌株的工业化应用提供了技术支撑。     

农杆菌介导的紫色红曲霉遗传转化体系的建立和优化

通过优化各种转化因素,建立了根癌农杆菌(Agrobacterium tumefaciens)介导红曲霉(Monascus)的高效转化体系:红曲霉在PDA培养基培养21 d后收集孢子,制备红曲霉孢子悬浮液,浓度为106个/mL,根癌农杆菌浓度为OD600值0.5,诱导剂AS浓度为100μmol/L,农杆菌与红曲霉在25℃共培养3 d。采用此转化体系构建了含有530多个转化子的红曲霉T-DNA插入突变体库。随机选取50株转化子菌株进行分子验证和稳定性检测,证明T-DNA成功插入红曲霉基因组DNA中,并能稳定遗传。最后,通过形态观察筛选出8株变异较大的菌株,为以后的红曲霉基因功能研究奠定了一定的基础。     

基于多基因分析对我国红曲霉属Monascus真菌的系统发育研究

红曲霉属Monascus具有重要的经济和生态价值,但对该属的物种识别和系统发育学研究有限。本研究首先对红曲霉属红色组内物种开展ITS和LSU序列的测定并综合分析,结合GenBank中相关物种序列及菌株的形态学特征,探讨红曲霉属的系统发育关系,鉴定出红色组3个种,弗罗里达组7个种。其次采用红曲霉色素表型控制基因簇部分基因pksKS序列进行分析,以期解决ITS和LSU等基因序列分析无法有效区分红色红曲与紫色红曲不同形态种的问题。通过分子克隆测序与直接测序结果的比较,以及对3个血红红曲菌株单核苷酸多态性的分析,解析了血红红曲种内遗传差异,首次在红曲霉属真菌中发现疑似红色红曲血红自然杂交种。最后综合ITS、LSU、pksKS序列和形态学分析的结果,统一了红曲霉属内物种的系统发育关系,确认红色组包括3个种：红色红曲M. ruber、紫色红曲M. purpureus、血红红曲M. sanguineus;发现3个变种：红色红曲发白变种M. ruber var. albidulus、紫色红曲橙色变种M. purpureus var. aurantiacus及紫色红曲火红色变种M. purpureus var. rutilus;弗罗里达组包括7个种：弗罗里达红曲M. floridanus、苍白红曲M. pallens、新月红曲M. lunisporas、阿根廷红曲M. argentinensis、累西腓红曲M. recifensis、黄色红曲M. flavipigmentosum、蜂蜜红曲M. mellicola。另外,发现1个疑似杂交种：红色红曲血红杂种M. ruber × sanguineus。结果表明,红曲霉属具有丰富的物种多样性,而且通过多基因和形态学分析可以将相近种区分开来。     

Pigments and citrinin biosynthesis by fungi belonging to genus Monascus

Citrinin is a mycotoxin, which is produced by fungi belonging to the genus Monascus, known in biotechnology as producers of azaphilone pigments. The relation between biosynthesis of these secondary metabolites was investigated in different species of the genus Monascus in batch-culture at the following cultivation conditions: T = 28 degrees C, agitation 220 rpm, and a medium, which induce citrinin production, containing ethanol as a carbon source. The screening was carried out with 16 fungal strains and the biosynthesis of citrinin and pigments was monitored quantitatively at the standard conditions mentioned above. Some kinetic parameters of the process have been determined. The values of the growth yield coefficient Y(X/C) were between 0.32 and 0.57. The amount of the extracellular red and orange pigments at the end of cultivation varied for the different strains between 0.09 and 1.33 OU/ mg dry weight, and 0.15 and 0.96 OU/mg dry weight, respectively. The amount of the total pigments measured was between 0.16 and 3.6 OU/mg dry weight, and between 0.21 and 3.39 OU/mg dry weight. The determined ratio 500 nm/400 nm, characterizing the pigment production, ranged between 0.60 and 1.06. Twelve of the investigated strains produced citrinin and pigments, two of them produced only pigments. Two strains were not able to produce neither pigments nor citrinin. Thus, the biosynthesis of citrinin appeared to be strain-specific and does not correlate with the pigments' biosynthesis by the fungal strains belonging to the genus Monascus.     

The effect of different nitrogen sources on pigment production and sporulation of Monascus species in submerged, shaken culture.

Thirty-nine strains from the genus Monascus were cultivated aerobically to study the relation between nitrogen nutrition and sporulation and pigment production. The effects of yeast extract, nitrate, ammonium, and ammonium nitrate have been compared. During cultivation the pHs of the different media are not the same, resulting in the formation of different coloured pigments. When the source of nitrogen is yeast extract or nitrate the pH is around 6.5 and red pigments are formed, whereas with ammonium or ammonium nitrate the pH is around 2.5 and the pigments are orange. It is proposed that only the orange pigments, monascorubrin and rubropunctatin, are produced biosynthetically and that the other pigments are formed from these by chemical transformations depending on the cultural conditions. The presence of organic nitrogen is optimal for growth and unfavourable for pigment production. Reduced growth and best pigment formation occurs with the three other nitrogen sources. Nitrate stimulates conidiation and sexual reproduction, while ammonium is inhibitory. Pigment production is better when conidiation is reduced. A mechanism is proposed for the control of sporulation and pigment production.     

Growth kinetics of biopigment production by Thai isolated <Emphasis Type="Italic">Monascus purpureus</Emphasis> in a stirred tank bioreactor

Monascus purpureus is a biopigment-producing fungi whose pigments can be used in many biotechnological and food industries. The growth kinetics of biopigment production were investigated in a liquid fermentation medium in a 5-l stirred tank bioreactor at 30°C, pH 7, for 8 days with 100 rpm agitation and 1.38 × 10⁵ N/m² aeration. Thai Monascus purpureus strains TISTR 3002, 3180, 3090 and 3385 were studied for color production, growth kinetics and productivity. Citrinin as a toxic metabolite was measured from the Monascus fermentation broth. The biopigment productions were detected from fermentation broth by scanning spectra of each strain produced. Results showed a mixture of yellow, orange and red pigments with absorption peaks of pigments occurring at different wavelengths for the four strains. It was found that for each pigment color, the color production from the strains increased in the order TISTR 3002, 3180, 3090, 3385 with 3385 production being approximately 10 times that of 3002. Similar results were found for growth kinetics and productivity. HPLC results showed that citrinin was not produced under the culture conditions of this study. The L*, a* and b* values of the CIELAB color system were also obtained for the yellow, orange and red pigments produced from the TISTR 3002, 3180, 3090 and 3385 strains. The colors of the pigments ranged from burnt umber to deep red.     

Pigmentation and Antibacterial Activity of Fast Neutron- and X-Ray-induced Strains of Monascus purpureus Went

Seven new strains of Monascus purpureus Went were induced by neutron and x-ray irradiation. The quantity and quality of pigments produced by these strains differed. Strains N4S and N11S produced twice as much pigment as normal, while another strain, N14S, was albino. An unknown orange pigment was found in young colonies of the N11S strain. This orange pigment reacted with alcohols and malt extract medium to form red pigments. Strains N4S, N11S, X2P, and wild type inhibited the growth of certain bacteria, especially the Bacillus species. Strain N11S had more antibacterial activity than wild type. A major active compound was isolated with an ultraviolet absorption spectrum that was related to those of the red pigments found in this fungus. The active compound(s) was named monascidin.     

Production of Extracellular Pigment by a Mutant of Monascus kaoliang sp. nov

A hyperpigment-producing mutant, R-10847, was derived from Monascus kaoliang F-2 (ATCC 26264) through a series of mutagenesis steps. The mutant produced a large quantity of Monascus pigment when grown in mantou (steamed bread) by solid culture. The mutant produced pigments extracellularly by extruding the pigments outside the cell in a lump together with some viscous substances. The productivity of pigment was about 100-fold greater than that of the wild type. The mutant lost the capability of spore formation, the growth rate decreased, and both the size and quantity of conidia were reduced. The color of the pigment produced by the mutant changed from orange to deep red.     

Production of water-soluble yellow pigments via high glucose stress fermentation of Monascus ruber CGMCC 10910

Monascus pigments are secondary metabolites of Monascus species and are mainly composed of yellow pigments, orange pigments and red pigments. In this study, a larger proportion of Monascus yellow pigments could be obtained through the selection of the carbon source. Hydrophilic yellow pigments can be largely produced extracellularly by Monascus ruber CGMCC 10910 under conditions of high glucose fermentation with low oxidoreduction potential (ORP). However, keeping high glucose levels later in the culture causes translation or a reduction of yellow pigment. We presume that the mechanism behind this phenomenon may be attributed to the redox level of the culture broth and the high glucose stress reaction of M. ruber CGMCC 10910 during high glucose fermentation. These yellow pigments were produced via high glucose bio-fermentation without citrinin. Therefore, these pigments can act as natural pigments for applications as food additives.

     

红曲色素的两种新结构

从中国科学院微生物研究所保藏红曲菌中,筛选得到一株高产红色素的红曲菌菌株(AS.3.4617)。经鉴定属于红色红曲菌(Monascus anka Sato).通过有机溶剂的萃取和两次硅胶柱层析,从该菌株中分离得到两种色素样品,高压液相色谱测定为纯色素样品。通过元素组成分析,核磁共振谱,快离子轰击,质谱和高分辨质谱分析确定,这两种色素与已知的六种红曲菌色素不同,为新发现的红曲菌色素,它们可能的分子式为:C_(25)H_(31)O_5N和C_(23)H_(27)O_5N。     

红曲菌利用甘油促进色素产生及其机制的研究进展

红曲色素(Monascus pigments,MPs)是红曲菌(Monascus sp.)的主要次生代谢产物,作为食品着色剂在我国已有上千年的应用历史。甘油,特别是生物柴油等生产过程中产生的甘油,作为一种相对廉价的碳源可被红曲菌等微生物利用,并可促进红曲色素的产生。本文对甘油促进红曲菌色素产生的相关研究进行综述,并对其机制进行分析。     

Change of Monascus pigment metabolism and secretion in different extractive fermentation process

Bioprocess and Biosystems Engineering - Monascus pigments that were generally produced intracellularly from Monascus spp. are important natural colorants in food industry. In this study, change of...     

红曲菌的色素与产生菌

介绍了红曲菌所产各种色素及其衍生物的化学结构和产生菌研究进展,以及红曲菌色素作为食品添加剂及防腐功能,活血、调节血脂、降血压及治疗胺血症等临床药效的原理。着重报道了作者筛选出的紫色红曲菌MonascuspurpureusNH4产生红斑素、红曲红素的培养条件,色素的提取及所产色素的理化特性。