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1.
真菌来源的抗氧化活性物质研究进展   总被引:1,自引:0,他引:1  
本文综述了食用菌、野生大型真菌、海洋真菌、植物内生真菌、虫生真菌、酵母等不同真菌产生抗氧化活性物质的研究进展,提出真菌来源的抗氧化活性物质研究建议,展望从真菌中提取抗氧化活性物质的发展前景。  相似文献   

2.
研究水分、温度对稻谷储存过程中真菌生长和主要储存品质的影响。将稻谷设为含水量分别为12.1%、13.1%、14.0%、15.1%、16.0%的样品,分别置于10、15、20、25、30、35℃温度条件下模拟储存180 d后,检测稻谷样品中真菌生长、发芽率和脂肪酸值的变化。结果表明,水分是真菌生长的决定因素,13.1%水分处于真菌生长临界水分以下,即使温度适宜真菌也不生长;14.0%处于真菌生长临界水分以上,水分越高越利于真菌孢子萌发生长,温度越高真菌生长速度越快;脂肪酸值受真菌生长的影响程度要大于水分和温度,13.1%以下水分稻谷,没有真菌生长,脂肪酸值上升缓慢。14.0%以上水分稻谷,一旦真菌生长,就会加速脂肪酸值的升高;发芽率受温度影响程度最大,高温储存半年,无论是否有真菌生长,发芽率基本降为0,低温储存不仅能抑制真菌生长还利于保持种子发芽率。  相似文献   

3.
评价DNA条形码用于蛋糕污染真菌鉴定的可行性,分析是否存在潜在的致病菌。从4种不同风味的霉变蛋糕上分离真菌菌株,依据真菌通用DNA条形码ITS序列对获得的真菌菌株进行鉴定。结果:从霉变蛋糕上共分离到34株真菌,根据ITS序列97%的相似性阈值鉴别出9种真菌,隶属于枝孢属、脉孢菌属、青霉属、曲霉属、链格孢属和鲁氏接合酵母等,这些多为空气中常见的真菌。这些真菌在ISHAM数据库中都能找到近缘的具有致病性的菌株,其中一些真菌属还包括产毒素的物种。虽然从每种风味蛋糕上分离到的真菌物种数有限,但回接试验表明分离到的真菌在两种不同风味的测试蛋糕上都可以生长,且蛋糕低温保藏可以延缓这些真菌的生长。结论:提高了对蛋糕上污染真菌多样性的认识,仅靠ITS序列难以将污染蛋糕的真菌准确鉴定到种,需要使用其它备用DNA条形码。本研究结论对蛋糕的合理保藏和食品安全具有一定的指导意义。  相似文献   

4.
提取6种甜酒酒曲的总DNA,利用真菌18S rRNA基因片段的通用引物NS1、Fung-GC,采用变性梯度凝胶电泳(PCR-DGGE)方法,进行不同甜酒酒曲中真菌多样性的分析。结果表明,6种甜酒酒曲中共分离出3属真菌和不可培养真菌,湖南韶山的甜酒曲中主要是扣囊复膜酵母属和根霉属的菌株;湖南湘潭甜酒曲中的真菌为酿酒酵母属、扣囊复膜酵母属和根霉属;湖南祁东、福建福州和浙江丽水甜酒曲中的真菌均为酿酒酵母属、扣囊复膜酵母属、根霉属和不可培养真菌;浙江兰溪甜酒曲中的真菌为根霉属和不可培养真菌。在传统的酒曲中的真菌主要是酿酒酵母属和扣囊复膜酵母属,此外不可培养真菌在甜酒酒曲中也起到非常重要的作用。  相似文献   

5.
云南复烤烟叶不同地点醇化过程中可培养真菌种群分析   总被引:1,自引:0,他引:1  
为较全面的了解云南复烤烟叶在不同地点醇化过程中真菌多样性,挖掘其中的有益微生物,提高烟草醇化品质,以复烤烟叶为试验材料,利用18S rDNA克隆测序技术,系统研究了其醇化过程中可培养真菌的种群结构。结果表明,醇化过程中,复烤烟叶叶面真菌数量除曲靖仓库在6月有所上升外,其余各地均随着醇化的进行而逐渐下降,其中曲靖和楚雄两地非常接近,元江最少;通过形态特征及18S rDNA鉴定,烟叶叶面真菌包括根霉属真菌、青霉属真菌、曲霉属真菌等24个真菌属(种)。不同地点,不同时期烟叶叶面真菌的数量、种类及优势种群不尽相同,而根霉属真菌始终为优势种群。  相似文献   

6.
真菌生长会导致粮食品质下降甚至真菌毒素污染,是造成粮食损失,引起食品卫生安全隐患的重要因素之一。当前,世界各国都十分重视粮食上真菌及真菌毒素污染的问题,明确粮食上真菌群落组成是真菌及毒素污染防控的关键。本文对粮食真菌的分类、危害以及我国粮食真菌群落组成及多样性研究进展进行了综述,介绍了真菌群落组成与真菌毒素污染的关系并探讨了真菌群落组成及多样性研究的应用前景,旨在为全面系统研究粮食真菌提供方法,从而为粮食真菌毒素精准防控的深入研究提供参考。  相似文献   

7.
利用nested PCR-DGGE技术分析江苏啤酒大麦真菌群落结构   总被引:1,自引:1,他引:0  
为了探索真菌群落对啤酒大麦麦芽的影响,首先要了解啤酒大麦真菌群落结构。文中采用9种不同方法提取了啤酒大麦总DNA,利用嵌套聚合酶链式反应-变性梯度凝胶电泳(nested PCR-DGGE)技术,分析了啤酒大麦真菌群落结构,明确了啤酒大麦中优势真菌种属信息。不同DNA提取方法,nested PCR-DGGE分析结果有显著差异。啤酒大麦中的主要真菌为Cochliobolus sativus、Alternaria alternata、Fusarium sporotrichioides、Coniothyrium fuckelii、Aspergillus sp.和Saccharomyces cerevisiae等子囊菌门真菌以及Sporobolomyces roseus、Cryptococcus magnus和Entorrhiza fineranae等担子菌门真菌。该研究丰富了对啤酒大麦真菌群落结构的认识,同时也证明nested PCR-DGGE技术是一种能够快速有效地研究啤酒大麦真菌群落结构的技术。  相似文献   

8.
真菌被认为是影响稻谷安全储藏的重要风险因素,明晰真菌在稻谷中的生长规律,有效监测储藏过程中真菌的动态变化,并研发应用具有针对性的防控措施是减少真菌危害的关键。本文综述了国内外稻谷储藏中真菌生长特性、监测方法及防控技术的研究现状,以期为储藏稻谷中真菌危害的进一步研究及实际防控提供参考。  相似文献   

9.
食用真菌因其味道鲜美被广泛食用,并具有较高的营养价值和药用价值。多糖是食用真菌中最重要的活性成分之一。大量研究表明,食用真菌多糖具有抗氧化、抗肿瘤、抗炎和降血糖等功效。食用真菌多糖在医疗、食品和化妆品等领域被广泛应用。近年来,关于食用真菌多糖的提取、分离纯化及结构表征的相关研究越来越受重视。但提取和纯化方式不同将会导致多糖的生物学活性存在很大的差异。该文对食用真菌多糖的提取方法、纯化方法和结构特征进行整理、归纳和阐述,以期为食用真菌多糖的进一步研究提供理论参考。  相似文献   

10.
储存水分、温度和真菌生长对大豆品质的影响   总被引:1,自引:0,他引:1  
研究大豆储存过程中水分、温度和真菌生长对其品质的影响。采用11.2%、11.8%、12.7%、13.9%和14.7%水分的大豆,分别置于10、15、20、25、30、35℃下模拟储存,周期180 d,检测储存真菌、发芽率和脂肪酸值的变化情况。结果表明,大豆储存中,真菌生长受储存水分和温度的影响,水分是决定真菌生长的主要因素,而温度影响真菌生长速度。真菌生长临界水分(11.8%左右)以下储存,种子发芽率和脂肪酸值主要受温度的影响,20℃以下低温储存能维持较高的发芽率,30℃以上储存会加剧脂肪酸值升高。真菌生长临界水分以上储存,种子发芽率和脂肪酸值受真菌生长和温度协同作用的影响,大豆储存水分越高,真菌生长越快,即使低温也会在一定程度上导致大豆品质劣变。  相似文献   

11.
Background and Aims: This study investigated flavonoid composition and C13-norisoprenoids (β-damascenone and β-ionone) in Shiraz grapes and wines, their relationships and links to wine sensory properties. Methods and Results: Differences in the grape berry flavonoid profile were created by exposing bunches to varying levels of sunlight intensity through canopy manipulation. Grapes were harvested at similar maturity and three replicate wines were made for each treatment in both vintages. Grapes produced under shaded canopy conditions had reduced anthocyanins and skin tannins, but little effect on seed tannins was observed. Pigmented polymers and tannins in wines were related to berry flavonoid composition (anthocyanins, skin and seed tannins, and their ratios). In grapes and wines, no significant effects were observed in response to canopy manipulation for two hydrolytically released C13-norisoprenoids, β-damascenone and β-ionone. Relationships were established for wine flavonoid composition, wine colour density, sensory perception of the astringency-related mouth-feel attributes and a quality scale. A positive relationship between wine quality score and hydrolytically released β-damascenone in both berries and wines was found, but not for free β-damascenone or any quantified forms of β-ionone. Conclusion: Higher concentrations of anthocyanins and skin tannins in berries, coupled with a lower concentration of seed tannins were associated with higher wine quality. The ratio anthocyanins*skin tannins/seed tannins is proposed as an indicator of wine flavonoid composition, wine colour and wine quality. Excessive canopy shade was detrimental to berry and wine composition and intensified sensory detection of ‘straw’ and ‘herbaceous’ characters in the wines. Significance of the Study: This study increases the understanding of the balance and composition of flavonoid compounds and C13-norisoprenoids in berries and their relationship with wine composition and wine sensory properties, but also highlights the importance of a canopy microclimate assessment.  相似文献   

12.
Links between textiles, fashion, and architecture are examined in terms of their visual aesthetics and methods of realization. Both garments and buildings touch our everyday lives and can be seen as similar types of “outfits.” Pragmatic and expressive they provide protection and shelter while also reflecting taste and identity. As ever-new textiles and technologies are emerging, these are infiltrating both the world of fashion and that of architecture. Fashion references architecture, and architecture references fashion in human scale/proportions and harmony/balance of forms, while the correct choice of textile is crucial to their realization. Fashion is traditionally seen as being ephemeral and temporal and architecture as monumental and permanent but these notions are rapidly changing. Fashion is slowing down to embrace issues of sustainability, timelessness, and longevity while architecture is speeding up to take on aspects of flexibility, mobility, and change. It is proposed that the future will move towards a convergence that includes the bespoke where new textiles and technologies enable “outfits” to be made for wearing and for living in that are intimate and individual—tailored to suit and responsive to need.  相似文献   

13.
The physicochemical, milling and cooking characteristics of three commercial varieties of paddy viz. Jaya, PR 106 and Pb. Basmati no. 1 as affected by different dates of sowing nursery and transplanting, were investigated. Grain yield was adversely affected with late sowing and transplanting dates. Significant differences were recorded on the yield of head rice and brokens in the three varieties grown under different sowing and transplanting dates. The effect of normal and late dates of sowing on 1000-kernel weight and grain dimensions was significant for both paddy and milled rice. Protein content of rice was not affected by sowing dates but late transplantings resulted in higher values. Free fatty acids in rice and bran were significantly increased with late sowing and transplanting dates, however, the amylose content decreased under these situations. Late transplanting dates decreased the minimum cooking time but increased the solid losses in gruel. The late transplantings deteriorated the organoleptic properties of cooked rice and had higher values for clearing and spreading.  相似文献   

14.
A fluorometric-coupled reaction for the accurate and rapid determination d- and l-lactate and lactose, galactose in foods is presented. The method was found useful for an accurate determination of these metabolites in heterogeneous, opaque and colourful foods without pretreatments. Example for the determination of lactose, galactose, d- and l-lactate in milk, and yogurts and d- and l-lactate in milk, wine and beer is provided. Unexpectedly, we found that the composition of some commercial bio-yogurts produced in Israel is not consistent with the classical definition of yogurts. Thus, this method offers rapid and accurate methodology, which should be particularly valuable in food quality control.  相似文献   

15.
Cumin is a seed spice belonging to the family umbelliferae. Cumin and value added products from cumin are used in food flavoring and perfumery. Cumin contains volatile oil (3–4%), cuminaldehyde, the major active principle, which is present to an extent of 45–50%. Cumin and value added products from cumin, viz., cumin oil and oleoresin are exported. Cumin powder forms the main component of many spice mixes and curry powders. Cuminaldehyde is an important phytochemical and possesses many health benefits. Alcohol and water extract of cumin are reported to possess many nutraceutical properties like antiallergic, antioxidant, anti-platelet aggregation, and hypoglycemic. Cumin and value added products from cumin can be a good source of nutraceuticals with many biological activities. Incorporation of cumin into food products will have the benefits of a flavorant and nutraceutical at the same time. In the present review, the chemistry, processing, and biological activities of cumin and its components are discussed.  相似文献   

16.
Lipid analysis, providing an understanding of chemistry and structure, begins in Continental Europe during the 18th century. However, it necessarily takes until the mid 20th century before methodology develops sufficiently for the production of fast accurate and quantitative data. Up to 1922 analytical methodology relies on good observation and painstaking care, but only achieves bulk properties. Key early workers are Tachen and Scheele, followed by the great Chevreul, while Pelouze and Berthelot later added to his work. Thus by 1900 we had knowledge of the basic structure and composition of fat, enabling Lewkowitsch to publish manuals of data and simple analytical methodology in 1901 and 1922. Hilditch, in the UK from 1925 to 1952, much improved analytical methods and knowledge, leading to publication of the major work, The Chemical Constitution of Natural Fats. In 1951 Martin and James published the key development of gas chromatography. It led to rapid advancement of knowledge in structure, chemistry and biochemistry of lipid. Parallel and future develoments in thin layer and high performance liquid chromatography complemented this. Other developments, in particular NMR and mass spectrometry, have created an exciting completion to the success of 20th century lipid analysis. © 2001 Society of Chemical Industry  相似文献   

17.
为研究赤霞珠葡萄果实发育过程中不同组织(果皮、果肉和种子)内源激素的含量变化及其与果实成熟的关系,用高效液相色谱-质谱联用技术测定果实发育过程中果皮、果肉以及种子中脱落酸(abscisic acid,ABA)、生长素(indole acetic acid,IAA)、赤霉素(gibberellin A_3,GA_3)、茉莉酸(jasmonic acid,JA)和水杨酸(salicylic acid,SA)的含量。结果发现,在葡萄果实生长发育过程中,葡萄果皮和果皮中ABA含量呈双S型变化,花后20 d左右,ABA含量较高,随着果实膨大开始下降,随后开始上升,至转色中期达到最大值,随着果实的成熟缓慢下降;果皮、果肉和种子中GA_3含量均是从果实膨大期开始上升,膨大后期下降,随后在转色初期又开始上升,随后下降;JA含量的变化与GA_3类似;果皮和果肉中IAA含量首先略微下降,在果实快速生长期迅速上升,并达到峰值,随着果实进入转色期,含量逐渐下降并保持稳定,果实膨大期之前,种子中IAA含量较高,随着果实膨大降低,并维持在较低水平,SA含量的变化与IAA类似。结论:ABA、GA_3、JA含量与赤霞珠果实成熟有关,IAA、GA_3、SA、JA含量与赤霞珠果实生长有关。  相似文献   

18.
The purpose of this study was to evaluate the levels of cadmium, mercury, iron, copper, manganese and zinc in lamb liver and kidney from six areas in Iceland and to compare the results against aerial deposition data for the same elements obtained using moss as an indicator organism. The total number of samples was 96 for each organ. Cadmium was determined by graphite furnace atomic absorption spectrophotometry, mercury by coldvapour atomic absorption, and iron, copper, manganese and zinc by inductively coupled plasma atomic emission spectrophotometry. Analysis of variance determined significance differences among means for areas, and Pearson's correlation coefficients were calculated to study correlation among trace elements in liver and kidney. The mean fresh weight concentrations in lamb liver and kidney respectively were 0.045 and 0.058mg kg -1 for cadmium, 0.009 and 0.012mgkg -1 for mercury, 141 and 52.7mgkg -1 for iron, 28.1 and 2.89mgkg -1 for copper, 4.01 and 1.13mgkg -1 for manganese and 48.7 and 25.2mgkg -1 for zinc. Concentrations of cadmium, mercury and copper in the liver and kidney of the Icelandic lamb were low compared with data from other countries. Iron concentrations in the organs, however, were high. No sample exceeded 46% of the proposed maximum level for cadmium in organs for human consumption in the EC. Cadmium, mercury, iron and copper in the liver and kidney differed significantly between areas. Deposition of cadmium and copper in moss was not a useful indicator in the evaluation of the susceptibility of the Icelandic lamb to accumulation of cadmium and cop per. However, iron levels in Icelandic lamb liver showed the same pattern as results for iron from the moss study. The cadmium and mercury levels of organs from lambs grazing in the vicinity of Mount Hekla a few months after its eruption did not indicate a significant contamination from volcanic activity.  相似文献   

19.
窖泥微生物总DNA的提取纯化研究   总被引:1,自引:1,他引:1  
窖泥是产生白酒中香味物质的功能菌的生长繁殖载体,白酒中的呈香呈味物质主要是由窖泥微生态中的己酸菌、丁酸菌、甲烷菌等代谢产生和酯化生化反应生成。从窖泥中提取微生物总DNA,经纯化、PCR扩增等处理分析,可跟踪检测不同时期、不同轮次发酵后窖泥中的各菌种、菌群的变化,对养窖护窖、发酵过程控制、提高发酵糟醅质量和酒质等生产都具有指导意义。  相似文献   

20.
The aim of this paper was to establish the correspondence between the anthocyanic profiles of grapes and wines produced in Uruguay. For this purpose, Tannat, Cabernet-Sauvignon and Merlot vineyards in 2002 and 2003 were considered. Grapes samples were taken in the harvest and were peeled, and the skins were stored at −20 °C until analysis. After that, skins were macerated in a 12% ethanol and pH 3,2 solution for 24 hours. Vinifications were carried out with 50 kg of grapes and two replications per vineyard. The anthocyanic composition of the skins extracts and the wines were analysed by H.P.L.C. Delphinidin, petunidin and non-acylated glucosides proportions were significantly higher in Tannat skins and wines. Malvidin and acetates proportions were significantly higher in Cabernet-Sauvignon grapes and wines. Peonidin and coumarates proportions were higher in Merlot skins and wines. The relation between the acetyl and coumarylic forms allowed the differentiation of Cabernet-Sauvignon grapes and wines from Merlot and Tannat, but not these among themselves. The combined consideration of the anthocyanic forms proportions allowed the discrimination of the totality of the grapes and wines samples of each variety.  相似文献   

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