富硒虫草的研究进展

虫草是传统名贵中药,具有抗癌、抗菌、调节免疫、降血脂、降血糖等广泛的药理作用;硒是人体必需的微量元素,具有抗癌、抗氧化、抗衰老等多种生理功能,与许多种疾病密切相关。利用虫草菌将无机硒转化为有机硒,实现虫草与硒的有机结合,研究功能更好的富硒虫草,无论作为药用、保健品还是补硒食品都具有很重要的现实意义。本文综述二十余年来富硒虫草的研究状况。     

秦巴山区富硒蛹虫草有效成分及硒存在形态分析

为探究秦巴山区富硒蛹虫草有效成分及硒存在形态,以秦巴山区蛹虫草CM-1518为研究对象,研究不同质量分数亚硒酸钠(0～500 mg/kg)对蛹虫草生长发育的影响,并对其有效成分及硒存在形态进行分析。试验结果表明当亚硒酸钠质量分数为100 mg/kg时,蛹虫草鲜质量最高,为293.41 g/盒。当亚硒酸钠质量分数为200 mg/kg时,虫草素、虫草酸含量最高,分别为1.06 mg/g和2.10 mg/g,表明硒与虫草素和虫草酸可协同增效,但虫草多糖含量变化规律不明显,亚硒酸钠的添加不利于腺苷的合成积累。经计算,富硒蛹虫草中有机硒所占百分比均高达99.9%,低浓度的亚硒酸钠可促进可溶性蛋白和可溶性多糖中硒的合成,但高浓度的硒却降低其合成,且富硒蛹虫草中可溶性多糖中硒含量高于可溶性蛋白硒含量。试验表明适宜浓度的亚硒酸钠可促进蛹虫草生长发育及有效成分合成积累。     

富硒条件下蜜环菌菌株硒耐受性及胞外酶生物活性的研究

[目的]通过对蜜环菌(Armillaria mellea)的富硒驯化,研究各菌株硒耐受性、有机硒含量及生物活性的变化规律,从而获得生物活性更强的蜜环菌,并对富硒蜜环菌的生物学特征进行初步研究.[方法]以Na2SeO3为无机硒试剂对蜜环菌进行富硒驯化;采用氢化物原子荧光光谱法测定蜜环菌的硒含量,热水浴法测定蜜环菌的无机硒...     

富硒产品中硒的形态分析及化学评分模式的建立

采用微波水解、HPLC-HG-AFS法测定了硒蛋白粉、硒蛋白片、肽粉、富硒原料等19种硒产品中的总硒、硒代氨基酸和亚硒酸根离子[Se(IV)],分析了硒代氨基酸、Se(IV)和其他形态硒占总硒的百分比及不同形态硒代氨基酸的组成比例。以此为依据,将硒产品分为硒蛋白型、单一硒代氨基酸型、其它形态硒型及有机无机硒混合型。根据DBS42/002-2014规定建立了富有机硒产品评分模式,其中18种为富有机硒产品;根据适硒地区母乳中硒代氨基酸的组成比例提出了硒代氨基酸的化学评分模式,评分结果显示13种以蛋白态硒为主的硒产品中硒代氨基酸的组成比例均与母乳相差甚远,不利于人体平衡吸收利用,其中10种SeMet含量远远超过人体所需,SeCys_2为限制硒代氨基酸。该评分模式的建立对硒产品的开发具有指导意义。     

丙酸菌乳酸菌富硒发酵蔬菜的研制

目的 对丙酸菌乳酸菌富硒发酵蔬菜进行初步研制。方法 富硒丙酸菌、乳酸菌泡菜制作工艺流程：原料（洗涤整理）切分→盐水浸泡→装坛并放入辅料→加入老盐水（含乳酸菌）接种丙酸菌、Ｎａ２ＳｅＯ３１００μｇ／ｍｌ→培养。按泡菜、酸菜感官评分方法及评分标准,对不同处理的泡菜进行色、香、味、气、质地及滋味评分。并作产品无害化指标：Ｅ．Ｃｏｌｉ及亚硝酸盐浓度检测。采用３,３’－－二氨基联苯胺萃取分光光度法测定发酵蔬菜硒含量。蔬菜试样的试验指标有总硒质量分数「μｇ／ｇ」,有机硒质量分数「μｇ／ｇ」,以及有机硒占总硒的质量分数,分别代表该蔬菜对硒的吸收率变化及把无机硒转化成有机硒的转成率变化。结果 蔬菜虽未加硒作预泡处理,而是直接进行富硒发酵,泡制二天即可达到要求,随着泡制时间延长有机硒占总硒的质量分数有所下降,但下降幅度不如前者明     

硒的检测技术研究进展

硒是人和动物必需的微量元素之一,其存在形态划分为有机硒和无机硒,本文对总硒、有机硒的多种检测方法、原理及研究进展进行了综述,为硒产品开发研究工作提供依据。     

饲料中添加高剂量有机硒和无机硒对异育银鲫生长性能、组织硒蓄积和血液生化指标的影响

为探究饲料中高剂量的有机硒和无机硒对异育银鲫(Carassius auratus gibelio var. CAS V)的生长性能、硒蓄积和血浆生化指标等方面的影响,以硒代蛋氨酸(有机硒)和亚硒酸钠(无机硒)作为不同类型的硒源,初始体重为(62.95±0.23) g异育银鲫为研究对象,进行了为期90d的养殖实验。实验结果表明,饲料中添加0、10和20 mg/kg的有机硒和无机硒对异育银鲫的存活和饲料干物质的表观消化率无显著影响;有机硒处理组硒的表观消化率随饲料有机硒的添加量增加而显著升高(P<0.05);饲料中添加无机硒对硒消化率无显影响(P>0.05)。在饲料中添加有机硒可以提高异育银鲫的生长(P<0.05),在20 mg/kg处理组中达到最高(P<0.05);而饲料中添加10 mg/kg无机硒处理组未显著改变异育银鲫的特定生长率(P>0.05),但高浓度的无机硒则显著降低了其特定生长率(P<0.05)。饲料中添加有机硒显著降低了异育银鲫的肝体比,添加10 mg/kg无机硒显著降低异育银鲫的肝体比(P<0.05);饲料中添加有机硒和无机硒对异...     

钝顶螺旋藻富硒培养条件的优化

硒是人和动物必需的微量元素 ,补硒可以防治多种疾病。有机硒具有低毒、高生物利用度的优点 ,目前主要寄希望于生物转化的途径来获得有机硒[1 ] 。植物对硒的生物有机化作用已有综述[2 ] ,并开发有富硒酵母[3 ] 、富硒菇类[4] 、富硒大蒜、富硒黄芪、富硒西洋参、富硒麦芽、富硒茶以及富硒鸡蛋、富硒牛奶等[5] 。螺旋藻是一种很有开发利用前景的藻类 ,但其含硒量极微 ,实验报道富硒螺旋藻对60 Ｃｏ γ射线胸部照射大鼠诱发肺炎和早期肺、肝纤维增生有防治作用[6] 。在培养液中添加亚硒酸钠可以实现藻类对硒的富集和转化 ,而且螺旋藻对无机硒…     

中国不同地区畜禽水产品硒含量分析

目的：检测中国不同地区普通和富硒猪肉、鸡肉、鱼肉中总硒含量,为评估居民硒摄入量以及指导富硒产业发展提供依据。方法：2017年7—9月采集中国10个地区代表城市普通和富硒样品共516份,采用原子荧光光谱法测定总硒含量。结果：普通和富硒产品中,鱼肉总硒含量最高,其次猪肉,鸡肉与猪肉接近;西安三种产品总硒水平最高,克山和安康总硒水平最低。富硒产品与普通相比,猪肉和鸡肉总硒水平显著提高,富硒鱼肉略高于普通鱼肉。结论：鱼肉是很好的居民膳食硒来源,但富硒作用不显著;富硒猪肉和鸡肉产业发展不平衡,亟需制定相应的科学技术与国家相关标准。     

富硒生物样品中硒的价态和形态分析

本文利用2,3—二氨基萘(DAN)荧光法测定了富硒玉米粉、硒酵母蛋白等样品中四价硒、六价硒、有机硒含量及总硒量。进一步验证了差减法测定不同价态硒含量的实验方法     

Biological immobilization of fertilizer phosphorus

Summary Comparable uncultivated and cultivated Coastal Plain soils of New Jersey were analyzed for total inorganic and total organic soil P. Inorganic P was found to be greatly increased as a result of intensive fertilization. Organic P increased in most soil series examined, and up to 30 per cent of gains in total P in cultivated soils could be accounted for as increases in soil organic P. C: organic-P ratios in uncultivated soils were much higher than those usually encountered in soils containing humified organic matter. Cultivation has led to a considerable lowering of these ratios, as a result of decreases in organic-C contents and increases in organic-P contents.Paper of the Journal Series, New Jersey Agricultural Experiment Station, Rutgers University. The author is now with the Agricultural State University, Wageningen, Netherlands     

高生物量富硒酵母的选育及培养条件初步优化

通过筛选、单倍体分离、诱变和原生质体融合,从融合子中选育了一株高生物量富硒酵母菌株（编号为ZFF-28）,其细胞硒总含量分别是原始亲株ZY-67和ZY-198的2.8倍和2.0倍。通过单因素实验和正交试验设计,确定了优化培养条件：6%糖浓度的蔗糖糖蜜,添加0.5% (NH4)2SO4、0.1% H3PO4、60μg/mL Se,pH60～6.5,装液量50mL/250mL三角瓶,接种量10%,培养时间25h。在优化培养条件下,菌株ZFF_28的生物量可达8.2g/L,细胞中硒的含量达2050μg/g,硒总含量达到了16810μg/L,是培养条件优化前的1.3倍。细胞硒含量的91%为有机硒。     

库拉索芦荟富硒栽培技术研究

通过在大棚条件下盆栽芦荟,以不同浓度梯度的硒营养液作为外源硒,采用根系施硒和叶面喷洒施硒两种方式,分别在补硒后的不同时间段检测芦荟总硒、有机硒、芦荟苷、芦荟多糖、芦荟总氨基酸的含量,研究施不同浓度硒营养液对库拉索芦荟营养成分的影响。结果表明,在大棚条件下,使用400mg/L硒营养液叶面喷施时,库拉索芦荟硒富集效果最好,于叶喷后第一周期、第二周期、第三周期取样检测,总硒分别为:11.75、31.40和59.70mg/kg,有机硒分别为:8.99、27.00和52.60mg/kg;芦荟苷含量分别为2 690、1 830和4 350mg/kg,芦荟多糖含量分别为39.13、55.31和30.13mg/mL,氨基酸含量分别为0.41、0.47和0.63g/100g,该处理明显优于其它处理组。说明芦荟适当进行补硒会促进芦荟多糖、氨基酸的合成。     

Influence of selenium sources on age-related and mild heat stress-related changes of blood and liver glutathione redox cycle in broiler chickens (Gallus domesticus)

Selenium is an essential trace element that up-regulates a major component of the antioxidant defense mechanism by controlling the body's glutathione (GSH) pool and its major Se-containing antioxidant enzyme, glutathione peroxidase (GPX). Evidence has emerged suggesting that organic selenium, natural seleno-amino acids found in plants, grains and selenized yeast, maintains the antioxidant defense system more efficiently than inorganic selenium. Inorganic selenium is a pro-oxidant, whereas organic selenium possesses antioxidant properties itself. As a pro-oxidant, inorganic selenium is not suitable for animals or humans. Therefore, we examined the GSH–GPX system in broiler chickens and determined that organic selenium was indeed more beneficial than inorganic selenium. Chickens fed the organic selenium as Sel-Plex^®, a selenized yeast, had elevated GPX activity in both blood and liver in a thermoneutral environment and after heat distress. More importantly, the ability to reduce the oxidized glutathione (GSSG to 2 GSH) was enhanced and facilitated by maintenance of glutathione reductase activity. Organic selenium-fed chickens were less affected by mild heat distress than inorganic selenium-fed chickens, and this assessment was based upon less induction of heat shock protein 70 (hsp70) in organic selenium-fed chickens. Our results clearly show that heat distress, a potent inducer of oxidative stress and hsp70, can be partially ameliorated by feeding organic selenium. We attribute this observation to an enhanced GSH–GPX antioxidant system in organic selenium-fed chickens.     

Efficient Preparation of Selenium/Glutathione-Enriched Candida utilis and Its Biological Effects on Rats

The main purpose of this study was to prepare selenium/glutathione-enriched Candida utilis and investigate its effect on growth performance, antioxidant capacity, and immune response in rats. The preparation of the selenium/glutathione-enriched yeast was conducted using fed-batch culture for high cell density. The optimal culture conditions for increased intracellular organic selenium and glutathione contents were as follows: the concentrated medium was fed beginning at 12?h using a polynomial feeding strategy until a total glucose concentration of 150?g/l was reached, and sodium selenite was continuously added together with glucose to a total concentration of 60?mg/l. As a result, 81?% of sodium selenite was assimilated and transformed into organic selenium by C. utilis under optimal conditions, which in turn resulted in greater glutathione accumulation and lower malondialdehyde cellular content in the yeast. To investigate and compare the effects of the prepared selenized C. utilis and other dietary supplements, 40 female rats were divided into five groups of eight rats each, following a randomized block design. Experimental feeding was conducted for a period of 6?weeks. Selenium supplementation with inorganic selenium (sodium selenite) and organic selenium (selenized C. utilis) showed better results than the control and other groups supplemented with yeast with or without glutathione. The body mass of rats, selenium deposition, and oxidative enzymes activities in both serum and liver samples, and immunity responses were all significantly improved by selenium supplementation, and between the two sources, organic selenium was more effective than inorganic selenium.     

硒肥对马铃薯硒素吸收、转化及产量、品质的影响

通过设对照(CK)、保水缓释硒肥(W)、生物炭基硒肥(C)、硒酸钠硒肥(S)4个处理来研究不同硒肥对马铃薯(品种为早大白)硒素吸收、转化及产量、品质的影响。结果表明:各处理马铃薯各器官硒含量在生育期内总体上呈下降趋势,马铃薯各器官的硒含量呈现:苗期根茎叶片;成熟期叶片茎块茎的特点;随着硒肥用量的增加,W处理下的总硒、无机硒、有机硒含量呈增大趋势,产量、有机硒转化率、粗蛋白、还原糖和Vc呈先升高后降低的趋势;C处理和S处理下,马铃薯以上各指标均呈先升高后降低的趋势,在低施硒量(0.126 kg/hm2)时,3种硒肥显著降低了马铃薯块茎淀粉含量,之后随着施硒量的增加淀粉含量变化不显著;与对照相比,3种硒肥在适宜施硒量(0.379 kg/hm2)时,马铃薯产量提高了4.87%—5.44%,粗蛋白含量增加了12.18%—20.03%,还原糖提高了6.45%—12.90%,Vc含量提高-0.54%—3.11%,有机硒转化率增加13.00%—15.10%,淀粉含量增加了-0.73%—1.12%;综合考虑3种硒肥对马铃薯含硒量、产量、品质的影响,W处理最佳,C处理次之,S处理最差。     

Organic carbon dynamics in shelf edge sediments off the hebrides: A seasonal perspective

A benthic transect across the Hebridean Shelf Edge was sampled 9 times during 1995–96. Sediment samples from within the surface mixed layer were analysed for organic and inorganic carbon content, porosity, grain size and stable carbon isotope ratio. The organic carbon content is always <1% dry weight. Inorganic carbon content is 17–65% CaCO₃. There is no significant seasonal variation in organic or inorganic carbon contents despite changing productivity in the water column. However, there is an inverse relationship between organic carbon content and median grain size. The isotopic composition shows strong seasonal variation which reflects the increase in phytoplankton detritus at the sediment-water interface during spring/summer. The results suggest a small but rapid burial flux. However, the study area is not a significant depocentre for organic carbon.     

超临界CO_2萃取冬虫夏草子座挥发性成分的GC-MS研究

报道冬虫夏草挥发性成分的组成,为其进一步的研究工作奠定基础。采用超临界CO2萃取法从冬虫夏草子座中提取挥发性成分,气相色谱-质谱联用技术对其化学成分进行分析。超临界流体萃取物共鉴定了39种组分,占总馏出组分的86.6%以上,占色谱总馏出峰面积的98.56%以上。已鉴定组分中,含量最高的为油酸,相对含量25.6%;其次为亚油酸,相对含量22.67%;再次为棕榈酸11.86%。超临界CO2萃取法能更真实、全面的反映药材中的化学成分,适合于珍稀中药材相关组分的测定。     

纳米硒对紫色马铃薯生长及其矿质元素含量和品质特性的影响

以紫色马铃薯品种‘黑美人’为试材,采用水培法,分别用不同浓度(0、0.38、0.19和0.095 mmol/L)纳米硒溶液对紫色马铃薯进行叶面喷施处理,研究纳米硒对紫色马铃薯生长、矿质元素含量及品质特性的影响。结果表明:(1)与对照相比,各硒处理马铃薯的生物量与单株结薯数均显著增加,其中喷施0.095 mmol/L硒处理的生物量最高且增幅达1.5倍,喷施0.19 mmol/L硒处理的单株结薯数显著增加2.2倍。(2)纳米硒能够显著提高紫色马铃薯叶片、根系、块茎硒含量,各器官硒含量大小呈现:根系>叶片>块茎的特点,且喷施0.095 mmol/L硒处理块茎总硒含量达0.106 mg/kg,较对照显著提高0.65倍,达到了马铃薯块茎的富硒标准;同时纳米硒可在不同程度上调控K、Ca、Mg、Mn、Zn在马铃薯各器官中的分配。(3)随施硒浓度的增加,紫色马铃薯块茎中淀粉、可溶性蛋白及游离氨基酸含量呈先增加后降低的变化趋势,均在喷施0.19 mmol/L硒处理下达到最大值,且较对照分别显著增加56.33%、26.91%和27.89%;块茎中花青素、可溶性糖含量呈下降趋势,均在喷施0.095 mmol/L硒处理下达到最大值,且较对照分别显著提高24.73%、25.33%;而块茎中硝态氮含量呈上升趋势,在喷施0.095 mmol/L硒处理下最低并较对照显著降低34.82%。研究表明,叶面喷施0.095~0.19 mmol/L纳米硒溶液能够显著促进紫色马铃薯生长和单株结薯数,提高硒元素含量,调控矿质元素含量在器官中分配,有效改善其块茎品质特性。     

冬虫夏草及杜仲磷脂成分的研究

本文对不同产地的冬虫夏草及杜仲磷脂成分进行了分析研究。以钼蓝比色法测定了它们的总磷脂含量,采用薄层色谱扫描和吸光度比例系数校正法测定了其磷脂组成及相对百分含量。冬虫夏草约含8种磷脂组分,主要成分为磷脂酰胆碱、磷脂酰叽醇、磷脂酰丝氨酸、磷脂酰乙醇胺和磷脂酸。杜仲约含6种磷脂组分,其中以溶血磷脂酰胆碱和磷脂酰胆碱为主。