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1.
红酵母及红酵母产类胡萝卜素研究进展   总被引:1,自引:0,他引:1  
类胡萝卜素是安全有效的营养添加剂,因此被广泛用作药品、食品的着色剂和营养强化剂及饲料添加剂等。本文评述了红酵母利用农副产品和工业废料发酵产类胡萝卜素的研究进展,对影响类胡萝卜素产量和酵母生物量的多种因素进行了探讨。以廉价的农副产品作为营养源可降低成本,实现工业废料的资源化利用,减少对环境的污染,具有实际意义和社会意义。  相似文献   

2.
类胡萝卜素是对人体有益、色泽鲜艳的一类有机物,现如今被认为是最有发展潜力的食用色素添加剂之一,市场需求量巨大。微生物法发酵生产类胡萝卜素以其菌种种类多、发酵周期短、产品生理活性高等优点被业界所关注。对比分析利用4类不同微生物生产类胡萝卜素在生产条件、产品特性等方面的异同,提出提高产品产量和质量的措施和建议,为微生物发酵生产类胡萝卜素的深入研究和工业化生产提供参考。  相似文献   

3.
研究了红酵母RY-98菌株产生类胡萝卜素的营养与环境条件,并对发酵过程生理现象的变化作了测试。结果表明:培养基组成、糖浓度和添加剂以及培养基初始pH值、通气量(摇瓶装量)与培养时间等,均对该菌细胞生物量和类胡萝卜素产量有影响,其中ZS添加剂的加入可以明显促进菌体类胡萝卜素的形成,这是本次研究的新发现,在初步优化的培养基组成(葡萄糖40g/L、玉米浆15g/L、(NH4)2SO42g/L、ZS添加剂1g/L)和培养条件下,菌体生物量与类胡萝卜素含量分别为27mg/mL和498.2μg/g,发酵液产色素能力为13.3mg/L。通过观测发酵过程生理现象的变化,认为该菌类胡萝卜素是菌体的次生代谢产物,主要形成于对数生长期的末期和稳定期。  相似文献   

4.
以废弃的柚子皮为原料,探讨不同萃取剂、料液比、时间、温度对类胡萝卜素提取得率的影响;同时研究光照、温度、酸碱度、金属离子、氧化剂、还原剂及常用食品添加剂对类胡萝卜素稳定性的影响。结果表明,柚子皮中最佳提取工艺条件:萃取剂为丙酮,料液比为1∶30g/mL,浸提时间为60min,提取温度为20℃,类胡萝卜素的得率为305.98mg/kg。柚皮中类胡萝卜素的稳定性差,强光照射能加速类胡萝卜素降解;温度越高类胡萝卜素分解得越快;氧化剂对类胡萝卜素的稳定性有破坏作用,还原剂对类胡萝卜素的稳定性影响不大;酸性条件下类胡萝卜素稳定,高碱性条件下类胡萝卜素不稳定;金属离子Cu2+、Fe2+、Fe3+对类胡萝卜素分解有破坏作用;酸味剂能促进类胡萝卜素的降解,防腐剂与甜味剂对类胡萝卜素的影响不大。  相似文献   

5.
红酵母产生类胡萝卜素的研究   总被引:10,自引:0,他引:10  
研究了红酵母RY-98菌株产生类胡萝卜素的营养与环境条件,并对发酵过程生理现象的变化作了测试.结果表明培养基组成、糖浓度和添加剂以及培养基初始pH值、通气量(摇瓶装量)与培养时间等,均对该菌细胞生物量和类胡萝卜素产量有影响.其中ZS添加剂的加入可以明显促进菌体类胡萝卜素的形成,这是本次研究的新发现.在初步优化的培养基组成(葡萄糖400g/L、玉米浆15g/L、(NH4)2SO42g/L、ZS添加剂1g/L)和培养条件下,菌体生物量与类胡萝卜素含量分别为27mg/mL和498.2μg/g,发酵液产色素能力为13.3mg/L.通过观测发酵过程生理现象的变化,认为该菌类胡萝卜素是菌体的次生代谢产物,主要形成于对数生长期的末期和稳定期.  相似文献   

6.
红酵母类胡萝卜素发酵研究   总被引:13,自引:0,他引:13  
对红酵母 RY-98菌株产生类胡萝卜素的培养基组成和培养条件进行了初步研究 ,并对发酵过程作了动态分析 .结果表明 :培养基组成、糖浓度和添加剂以及培养基初始 p H值、摇瓶装量与培养时间等 ,均对该菌细胞生物量和类胡萝卜素产量有影响 ,其中 ZS添加剂的加入可以明显促进菌体类胡萝卜素的形成 .在初步优化的培养基组成 (葡萄糖 4 0 g/L,玉米浆 1 5g/L,( NH4) 2 SO42 g/L,ZS添加剂 1 g/L)和培养条件 (培养基初始 p H6.0 ,装量 60 m L/2 50m L摇瓶 ,2 8℃培养 60 h)下 ,菌体生物量及类胡萝卜素含量分别为 2 7mg/m L和 4 98.2 μg/g.通过观测发酵过程生理现象的变化 ,确认该菌类胡萝卜素是菌体的次生代谢产物 ,主要形成于对数生长期的末期和稳定期 .  相似文献   

7.
虾青素的结构与功能   总被引:1,自引:0,他引:1  
虾青素是一种酮式类胡萝卜素,常用作鱼虾等水产养殖动物的饲料添加剂。动物实验表明虾青素有抑制肿瘤发生、增强免疫功能、延缓衰老等多方面的功能,在功能食品、饲料、化妆品和医药等方面有着广阔的应用前景。  相似文献   

8.
天然类胡萝卜素是一大类重要的食品着色添加剂、营养强化剂和抗氧化剂,本文概括了叶黄素、玉米黄质、虾青素、番茄红素和β-胡萝卜素的理化性质和卓越的生理功能,介绍了以上各类色素的加工工艺,展示了多种不同的主要剂型与在产品中的应用,说明了类胡萝卜素潜在的巨大的市场价值和提升空间。  相似文献   

9.
添加剂及金属离子对类胡萝卜素产率的影响   总被引:1,自引:0,他引:1  
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%。  相似文献   

10.
对动物组织中类胡萝卜素的分析、分布和类胡萝卜素特异性结合蛋白的研究进行了综述。动物组织中类胡萝卜素的提取主要采用混合有机溶剂提取;分析检测主要采用反相高效液相色谱法和二极管阵列检测器;类胡萝卜素主要由小肠黏膜吸收;脂蛋白被认为参与类胡萝卜素的转运;β-胡萝卜素可经生物转化生成视黄醇;动物各组织对类胡萝卜素表现出选择性吸收,且这种选择性吸收因物种不同而差异显著;类胡萝卜素在吸收过程中相互之间存在交互作用,且这种交互作用主要发生在碳氢类胡萝卜素和含氧类胡萝卜素之间;类胡萝卜素的选择性吸收与交互作用被认为与组织中某种特异性结合蛋白的存在相关。  相似文献   

11.
Mycotoxins in botanicals and dried fruits: A review   总被引:1,自引:0,他引:1  
Botanicals are used in many countries for medicinal and general health-promoting purposes. Numerous natural occurrences of mycotoxins in botanicals and dried fruits have been reported. Aflatoxins or ochratoxin A (OTA) have been found in botanicals such as ginseng, ginger, liquorice, turmeric, and kava-kava in the USA, Spain, Argentina, India, and some other countries, while fumonisins have been found in medicinal wild plants in South Africa and in herbal tea and medicinal plants in Turkey. Zearalenone was identified in ginseng root. Dried fruits can be contaminated with aflatoxins, OTA, kojic acid, and, occasionally, with patulin or zearalenone. One main area of concern is aflatoxins in dried figs; bright greenish yellow fluorescence under ultraviolet light is associated with aflatoxin contamination. OTA in dried vine fruits (raisins, sultanas, and currants) is another concern. There are also reports of aflatoxins in raisins and OTA in dried figs, apricots, dried plums (prunes), dates, and quince. Maximum permitted levels in the European Union include 4 µg kg-1 for total aflatoxins in dried fruit intended for direct consumption and 10 µg kg-1 for OTA in dried vine fruit. This review discusses the occurrence of mycotoxins in botanicals and dried fruits and analytical issues such as sampling, sample preparation, and methods for analysis. Fungal contamination of these products, the influence of sorting, storage, and processing, and prevention are also considered.  相似文献   

12.
The content of ash, P, K, Ca, Mg, Na, Fe, Zn, Mn, Cu, Cr and Ni was determined in four species of brassicas: Brussels sprouts, broccoli, and green and white cauliflowers. The investigation covered the raw material, the material blanched or cooked before freezing and frozen products after 12 months of refrigerated storage and prepared for consumption. Frozen products were obtained by the traditional method of freezing the blanched material or by the modified method of freezing the cooked material. The processing of vegetables before freezing (washing, grinding, blanching or cooking) caused statistically significant decreases in most constituents analysed. Blanching did not basically change the content of sodium and calcium; or that of chromium in both types of cauliflower; copper and nickel in white cauliflower; and nickel and phosphorus in Brussels sprouts. Cooking in brine, however, caused increases in the content of ash, sodium and calcium in white cauliflower, decreases in the content of potassium and iron and, in some species, of the remaining constituents. In comparison with the traditional method, a greater content of most analysed elements was found in frozen products obtained by the modified technology and prepared for consumption. However, no significant differences were noted in the level of chromium in all the samples; in the level of calcium in broccoli and green cauliflower; of nickel in broccoli; of nickel, copper and zinc in white cauliflower; and of copper in green cauliflower.  相似文献   

13.
This study determined the distribution of drugs to different milk fractions according to their physicochemical properties. Hydrophilic drugs tend to concentrate in skim milk, whereas lipophilic drugs tend to concentrate in cream. The concentration of a drug in casein is related to its degree of binding to milk proteins. Thus, we aimed to determine whether withdrawal time in whole milk differs from that in cream, casein, and skim milk. Amoxicillin and tylosin were selected as prototype hydrophilic and lipophilic drugs, respectively. The study was conducted in vitro and in vivo to determine whether in vitro conditions reflect the distribution of drugs in the different milk fractions in vivo. The in vivo study was conducted using a crossover design on 6 healthy Holstein dairy cattle. First, amoxicillin (i.m., single dose, 14 mg/kg) was administered to cows. Following a 1-wk washout period, tylosin (i.m., single dose, 15 mg/kg) was administered. Concentrations of amoxicillin and tylosin in milk and milk fractions were measured using HPLC-UV. In the in vitro study, 0.04 to 400 μg/g of amoxicillin and 0.05 to 50 μg/g of tylosin were spiked to drug-free milk and the concentrations in milk and milk fractions were measured. In addition, the percentage of total protein in milk and milk fractions was determined. Amoxicillin accumulated more in skim milk than in cream and casein, both in vitro (92%) and in vivo (73%, skim milk-to-whole milk ratio). The distribution of tylosin in whole and skim milk was similar to that of amoxicillin in the in vitro study, in contrast to the accumulation of tylosin in cream seen in vivo. However, the accumulation ratio of tylosin in cream was lower than expected. By either method, tylosin was less concentrated in casein than in skim milk and cream. The percentage of total protein was similar in skim milk and whole milk and higher than in cream. Thus, amoxicillin accumulates less in cream and casein, suggesting that these fractions would pose a lower risk to the consumer. Tylosin was still present at the maximum residue limit (50 μg/kg) 24 h after injection in the casein fraction and 48 h after injection in the cream fraction.  相似文献   

14.
We investigated the contents in yolk and albumen of the trace minerals Se, Zn, Mn, Co, Cu, Mo, V, Cr, Ni, Tl, As and Cd in eggs from hens from three husbandry systems by ICP-MS. Conventional hens were given a commercial feed with added minerals, organic hens were given a feed based on organic feedstuffs also with added minerals, and courtyard hens were fed on cereals, legumes, grass and swill. Dietary Se, Zn, Mn, Co and Cu concentrations were lower in courtyard compared to conventional and organic diets; Cr concentration was highest in courtyard compared to organic diet. Trace element contents in yolks were higher than those in albumen. The highest content of Se in yolks was in organic, followed by conventional eggs. Zn contents were highest in courtyard yolk, followed by conventional, which in turn was higher than organic. Mn yolk contents were lowest in courtyard eggs; Cr contents were highest in courtyard eggs. The differences in albumen were in Zn and Cr values, which were highest in courtyard eggs. Τhe results provide baseline measurements of trace mineral contents of eggs and suggest measurable differences amongst eggs from hens in different husbandry systems; the physiological significance of these differences are discussed.  相似文献   

15.
目的了解大连市部分食品中重金属、有机磷及氨基甲酸酯农药残留、有机氯及菊酯农药残留以及环己基氨基磺酸钠的污染现状,对食品安全进行有效控制。方法按GB/T 5009—2003《食品卫生检验方法理化部分》检测铅、镉、汞、有机氯及菊酯农药残留、环己基氨基磺酸钠、有机磷及氨基甲酸酯农药残留。结果 39份样品中铅超标5份;镉和汞无超标样品。50份蔬菜样品中检出毒死蜱农药残留1份,超标1份;氯氰菊酯农药残留2份,超标1份。10份茶叶样品中检出联苯菊酯农药残留1份,无超标样品。有机磷及氨基甲酸酯农药、有机氯及菊酯农药、环己基氨基磺酸钠均无检出。结论大连市部分水产品中铅含量较高,污染较明显。需要进一步加强监测,控制污染。农药残留水平较低,只在个别蔬菜和茶叶中有不同程度的检出。  相似文献   

16.
湖北省十堰市烟田杂草的种类与分布   总被引:1,自引:0,他引:1  
为了明确湖北省十堰市主要烟叶产区烟田杂草的种类及分布,确定危害烟叶生产的主要杂草种类,为高产优质烟叶生产提供技术支撑,笔者于2011年9月在湖北省十堰市植烟面积比较大的郧西县、竹山县和房县的8个乡镇进行了烟田杂草种类及分布普查。普查采用对角线五点取样法,样方50 cm×50 cm,调查样方中的所有杂草种类和株(分蘖)数。结果表明,十堰市烟田杂草有62种,隶属于27个科。优势种为马唐、旱稗、尼泊尔蓼、铁苋菜和牛膝菊。发生频度较高的几种杂草依次为马唐、铁苋菜、尼泊尔蓼、腺梗豨莶和牛膝菊。危害最严重的杂草种类为马唐、铁苋菜和尼泊尔蓼,应作为防除重点。海拔高度对杂草的种类及分布有一定影响,在海拔较低的烟田中杂草种类较多。  相似文献   

17.
红车轴草不同部位中异黄酮含量的测定   总被引:11,自引:0,他引:11  
采用反相高效液相色谱法对红车轴草不同部位(花、茎和叶)中四种主要异黄酮(鸡豆黄素A、芒柄花黄素、染料木素和大豆黄素)的含量进行了测定,结果表明:以占干物质计,4种异黄酮总量,叶中含量最高(0.856%),茎次之(0.403%),花中含量较低(0.258%)。鸡豆黄素A和芒柄花黄素是红车轴草中两种最主要的异黄酮,主要分布在叶中,其次是茎,花中含量较低。染料木素和大豆黄素,无论是花、茎还是叶,含量均较低。  相似文献   

18.
Effects of duration of grain feeding on the concentration of endotoxic lipopolysaccharide (LPS) in digesta throughout the digestive tract and on acute phase proteins and LPS in peripheral blood were determined in Holstein yearling calves. Twenty-five Holstein yearling steer calves received either a forage-based diet containing 92% hay and 8% of a mineral and vitamin pellet on a dry matter basis (CON) or a moderate-grain diet, obtained by replacing 41.5% of the hay in the forage-based diet with barley grain, for 3 (MG3), 7 (MG7), 14 (MG14), or 21 d (MG21) before slaughter. Immediately before slaughter, blood samples were collected from the jugular vein. Immediately after slaughter, digesta samples were collected from the rumen, jejunum, ileum, cecum, colon, and rectum. Rumen liquid digesta, digesta from the intestines, and peripheral blood plasma were analyzed for LPS. Peripheral blood plasma and serum were analyzed for the acute phase proteins amyloid A, haptoglobin, and LPS-binding protein. Feeding the grain diet increased the LPS concentration in rumen fluid linearly from 15,488 endotoxin units (EU)/mL for CON to 70,146 EU/mL for MG7. Concentrations of LPS in rumen fluid in MG14 and MG21 were 61,944 and 56,234 EU/mL, respectively, and did not differ. The LPS concentrations in jejunal digesta were much lower than that in digesta elsewhere in the digestive tract, which suggests that ruminal LPS is broken down in the abomasum or proximal jejunum. The concentration of digesta LPS in the ileum was higher than that of digesta elsewhere in the intestines and similar to that in rumen fluid. The duration of grain feeding increased the LPS concentration in digesta in the ileum and cecum and tended to increase that in the colon cubically. Concentrations of LPS in this part of the digestive tract were highest in the MG3 and MG21 groups. The highest concentrations of LPS in digesta in the cecum, colon, and rectum were 3.7, 3.8, and 5.6 times higher than that in CON, respectively. Grain feeding and the increase in LPS in digesta were not accompanied by an acute phase response or a detectable concentration of LPS in peripheral blood. The absence of LPS in peripheral blood and the lack of increase in acute phase proteins indicated that the grain feeding protocol used in the current study and the accompanying changes in LPS concentrations of the digesta did not result in systemic inflammation.  相似文献   

19.
研究了云南省不同地区、不同品种及不同成熟度,不同部位烟叶中有机酸及乙醚提取挥发性成分含量.经分析得出,红河地区的烟叶有机酸含量较高,昆明、大理地区较低,但挥发性成分含量相反,大理地区最高,红河地区较低,玉溪、楚雄、昆明居中.评吸得分玉溪、大理地区烟叶相对好于其它地区.品种中以V2的有机酸含量最高,NC82的有机酸含量最低,挥发性成分含量相反,NC82较高,V2较低,云烟85、K326、红花大金元居中.初熟和适熟烟叶中有较高的挥发性成分含量,有机酸含量也较稳定,未熟和过熟烟叶中有机酸和挥发性成分依品种而定.对不同部位的烟叶,上部烟叶有较高的挥发性成分含量,中、下部烟叶次之,有机酸含量则中部叶最高,上、下部叶次之.  相似文献   

20.
Fungi are distributed worldwide and can be found in various foods and feedstuffs from almost every part of the world. Mycotoxins are secondary metabolites produced by some fungal species and may impose food safety risks to human health. Among all mycotoxins, aflatoxins (AFs), ochratoxin A (OTA), trichothecenes, deoxynivalenol (DON and T‐2 toxin), zearalenone (ZEN), and fumonisins (FMN) have received much attention due to high frequency and severe health effects in humans and animals. Malaysia has heavy rainfall throughout the year, high temperatures (28 to 31 °C), and high relative humidity (70% to 80% during wet seasons). Stored crops under such conditions can easily be contaminated by mycotoxin‐producing fungi. The most important mycotoxins in Malaysian foods are AFs, OTA, DON, ZEN, and FMN that can be found in peanuts, cereal grains, cocoa beans, and spices. AFs have been reported to occur in several cereal grains, feeds, nuts, and nut products consumed in Malaysia. Spices, oilseeds, milk, eggs, and herbal medicines have been reported to be contaminated with AFs (lower than the Malaysian acceptable level of 35 ng/g for total AFs). OTA, a possible human carcinogen, was reported in cereal grains, nuts, and spices in Malaysian market. ZEN was detected in Malaysian rice, oat, barley, maize meal, and wheat at different levels. DON contamination, although at low levels, was reported in rice, maize, barley, oat, wheat, and wheat‐based products in Malaysia. FMN was reported in feed and some cereal grains consumed in Malaysia. Since some food commodities are more susceptible than others to fungal growth and mycotoxin contamination, more stringent prevention and control methods are required.  相似文献   

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