黄曲霉毒素及其产毒菌株的实验室去毒法研究

目的 研究黄曲霉毒素及其产毒菌株的实验室去毒方法。方法 根据黄曲霉毒素及其产毒菌株的特点，采用强碱氢氧化钠和氧化剂次氯酸钠对其进行去毒处理。结果 采用4％～5％的次氯酸钠处理5min或2．0mol／L的氢氧化钠处理20min，均能达到破坏黄曲霉毒素的效果。结论 次氯酸钠和氢氧化钠均为黄曲霉毒素的良好去毒剂。     

用果胶酶产生测定法综合检验黄曲霉产毒性能

本文报道用果胶酶产生测定法测定黄曲霉的产果胶酶能力,结合黄曲霉产生黄曲霉毒素的能力,综合评价它们的产毒性。实验发现黄曲霉菌株的果胶酶产生能力大小不等。作者认为用实验室条件下的产毒能力和果胶酶产生能力二项指标检验菌株的实际产毒能力比单—用前者更符合实际情况。     

福建省厦门市同安区环境霉菌生态研究:4.产毒霉菌分布与原发性肝癌的关系

目的：探讨福建省厦门市同安区环境中产毒霉菌分布与原发性肝癌发生的关系。方法：对当地土壤、井水进行霉菌分离鉴定，检测黄曲霉毒素（AF）及杂色曲霉毒素（ST）产生菌株的产毒能力，与各乡镇原发性肝癌死亡率进行相关性比较。结果：在当地环境中检出大量可产生各种致肝癌毒素的霉菌菌株，而且AF及ST产生菌株检出率与各乡镇肝癌死亡率高低相吻合。其中散布着产毒能力极强的黄曲霉菌株，平均AFBI产量为1．88×105ng／g。结论：同安区环境中的产毒霉菌可能是当地原发性肝癌发生的一个致病因素。     

应用薄层层析技术快速检出黄曲霉毒素产毒菌株

应用薄层层析技术快速检出黄曲霉毒素产毒菌株马群飞蔡一新张荣标应用薄层层析技术（ＴＬＣ）进行产毒霉菌的分类鉴定时［１］，在某些黄曲霉（Ａｓｐｅｒｇｉｌｕｓｆｌａｖｕｓ）菌株的色谱带中，可见蓝色荧光斑点出现，并最终由实验确证为黄曲霉毒素（Ａｆｌａｔｏｘｉ...     

黄曲霉菌产毒和产菌核性能关系研究

对浙江省粮食中分离的８０株黄曲霉菌进行产菌核性能实验研究，在含３％ＮａＮＯ３蔡氏琼脂培养基上３０℃培养１２天，有５１．３％的黄曲霉菌株产生菌核，平均产菌核直径是８２７±１３１μｍ；没有发现产丰富小菌核产毒Ｓ型菌株；产菌核菌株大都是Ｌ型菌株；产毒菌株和非产毒菌株在产菌核比率及数量上差异不明显；在产菌核大小上，两类菌株有差异，产毒菌株产生较小的菌核。     

启东肝癌中黄曲霉毒素白蛋白加成物水平和p53蛋白表达的研究

对３０例启东肝癌病例和１６例对照用竞争抑制放射免疫法检测血清黄曲霉毒素白蛋白加成物，７例血清ＨＢｓＡｇ、抗－ＨＢｃ均阳性的手术病例的石蜡包埋组织用免疫组化法检测ｐ５３蛋白表达。结果表明，病例组黄曲霉毒素白蛋白加成物水平在１．０７～３．４６ｐｍｏｌＡＦＢ１／ｍｇ白蛋白之间，对照组在０．８５～２．９９ｐｍｏｌＡＦＢ１／ｍｇ白蛋白之间，两组比较无显著性差异。６例癌组织、４例癌旁组织ｐ５３蛋白表达阳性，且这６例阳性者黄曲霉毒素白蛋白加成物平均水平为１．８１５±０．６２２ｐｍｏｌＡＦＢ１／ｍｇ白蛋白。提示较长时间内病例和对照黄曲霉毒素暴露的蓄积剂量并无显著性差异。启东肝癌病例ｐ５３蛋白表达率很高，但引起ｐ５３高蛋白表达率的原因尚不能确定     

生物学法降解花生油中黄曲霉毒素的研究

以Ｆ２５（Ａｓｐｅｒｇｉｌｕｓｎｉｇｅｒ）为出发菌株制备的生物制剂ＢＤＡ，在使用量为油样的５％～１０％时，能使花生油中的ＡＦＢ１由１００～２０μｇ／ｋｇ降至２２．３～１．９μｇ／ｋｇ。在放大试验中，ＢＤＡ能使花生油中的ＡＦＢ１含量从２０μｇ／ｋｇ降至５μｇ／ｋｇ以下，ＢＤＡ的最适解毒温度为４５～４８℃，解毒时间２小时。ＢＤＡ选择谷壳等为解毒酶和水份的共同载体，通过固体发酵方式制备，经解毒处理的花生油样保持浓郁的花生油香味，对其酸价、过氧化值、折光系数、含水量几项指标均无明显的影响     

谷氨酰胺与谷氨酰胺双肽在小肠移植病人中的应用（附1例报告）

本文报道谷氨酰胺（ＧＩｎ）与甘氨酸谷氨酰胺双肽（Ｇｌｙ－ＧＩｎ）的小肠移植病人营养支持中的应用，一男性短肠综合征病人接受小肠移植，术后行全肠外营养支持，营养支持时添加ＧＩｎ０．３～０．４ｇ／（ｋｇ．ｄ）或Ｇｌｙ－ＧＩｎ０．６ｇ／（ｋｇ．ｄ）结果证实ＧＩｎ与Ｇｌｙ－ＧＩｎ均能提高静脉血ＧＩｎ浓度，减轻淤胆。     

乳酸菌对霉菌生长及产毒的影响

乳酸菌广泛应用于多种发酵食品中,黄曲霉和寄生曲霉及其毒素,即黄曲霉毒素是乳制品中主要的食源性致病物,现有资料表明某些乳酸菌可抑曲霉生长及产毒,本就乳酸菌抑制曲霉生长及产毒和可能的机制进行综述。     

脱氧雪腐镰刀菌烯醇,黄曲霉毒素G1对体外培养人外周血淋巴细胞凋？…

以细胞培养、流式细胞义ＤＮＡ含量分析及ＤＮＡ琼脂糖凝胶电泳方法研究了我国食管癌高发区磁县居民粮食中优势污染霉菌毒素脱氧雪腐镰刀菌烯醇（ＤＯＮ）和黄曲霉毒素Ｇ１（ＡＦＧ１）对人淋巴细胞凋亡的影响,流式细胞术（ＦＣＭ）检测结果显示,ＤＯＮ、ＡＦＧ１处理组淋巴细胞出现了典型的亚二倍体凋亡细胞峰,凋亡百分率与毒素作用时间（ＤＯＮ,２－７２小时;ＡＦＧ１;２－２４小时）及测量（ＤＯＮ;５０－２０００μｇ／Ｌ     

上海地区小麦中霉菌毒素的污染调查

采集上海郊县1995年的小麦样品100份．应用薄层层析法检测黄曲霉毒素B1（AFB1），用气相色谱法检测镰刀菌毒素脱氧雪腐镰刀菌烯酸（DON）和雪腐镰刀菌烯酸（NIV）。样品中DON、NIV和AFB1的污染率分别为53．0％、35．0％和45．0％，平均含量分别为280．9μg/kg、103．4μg／kg和0．86μg/kg。有17份样品同时检出AFB1，DON和NIV，可见镰刀菌毒素和黄曲霉毒素可共同污染粮食。本次调查我们还发现小麦中DON和NIV的含量存在相关关系（r＝0．55．P＜0．01），而AFB1与这两种毒素之间不存在相关关系（r＜0.10，P＞0.05）。     

Apple flavonols and n-3 polyunsaturated fatty acid–rich fish oil lowers blood C-reactive protein in rats with hypercholesterolemia and acute inflammation

Both quercetin glycosides and omega-3 polyunsaturated fatty acids (n-3 PUFA) are well established for their individual health benefits in ameliorating metabolic disease. However, their combined effects are not well documented. It was hypothesized that the beneficial properties of quercetin glycosides can be enhanced when provided in combination with n-3 PUFA. Therefore, the aim of the present study was to investigate the effects of apple flavonols (AF) and fish oil (FO), alone and in combination, on proinflammatory biomarkers and lipid profiles in rats fed a high-fat diet. Sixty male Wistar rats were randomly divided into 5 groups (n = 12) and fed a high-fat diet for 4 weeks. One of the 5 groups of rats was used as the high-fat control. The other 4 groups of rats were injected with lipopolysaccharide (LPS) (5 mg/kg body weight) intraperitoneally, 5 hours before euthanization. One of these 4 groups was used as the hypercholerolemic and inflammatory control (high-fat with lipopolysaccharide [HFL]), and the other 3 received AF (HFL + 25 mg/kg per day AF), FO (HFL + 1 g/kg per day FO), or the combination (HFL + AF + FO). Compared to the HFL group, the AF, FO, and AF + FO groups showed lower serum concentrations of interleukin-6 and C-reactive protein (CRP) levels. The AF, FO, and AF + FO also had lowered serum triacylglycerol and non–high-density lipoprotein cholesterol (HDL-C) concentrations, but higher HDL-C levels relative to the HFL group. An additive effect was observed on serum CRP in the AF + FO group as compared with the AF or FO groups. The results demonstrated that AF and FO inhibited the production of proinflammatory mediators and showed an improved efficacy to lower serum CRP when administered in combination, and they significantly improved blood lipid profiles in rats with diet-induced hyperlipidemia and LPS-induced acute inflammation.     

Interaction between caffeine intake and heart zinc concentrations in the rat

The purpose of the present study was to determine the levels of zinc in the hearts of growing post-weaning offspring, fetuses and their dams chronically fed caffeine. A further study was conducted to determine the distribution of Zn in subcellular heart fractions affected by acutely injecting caffeine into the veins of the adult rats. After delivery pups were raised on a 200 g protein/kg diet until day 22 of weaning. On day 22 randomly selected male offspring from each litter were divided into two groups. Group 1 was fed continuously on the same diet as a control, whereas in the experimental group offspring were fed on a 200 g protein/kg diet supplemented with caffeine (20 mg/kg). On day 49 the animals were killed and Zn, calcium and magnesium concentrations of the hearts were measured. In the second series of studies pregnant dams were randomly divided into two groups. Group 1 was fed on a 200 g protein/kg diet from day 3 of gestation, whereas in the experimental group dams were fed on the diet supplemented with caffeine. On day 22 of gestation the fetuses were surgically removed. The Zn, Ca and Mg concentrations of hearts of fetuses and dams were determined. In the third phase a caffeine solution was injected into the vein. After 45 min the hearts were removed and Zn levels in the subcellular fractions determined. The hearts of the growing offspring fed on a caffeine-supplemented diet consistently showed decreased Zn and Ca levels compared with the non-caffeine group.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of prior ethanol exposure on ethanol self-administration in a continuous access situation using retractable drinking tubes.

To examine whether exposure to ethanol influences subsequent ethanol consumption using a continuous access procedure, two groups of rats were given differing initial exposure to ethanol. One group underwent a sucrose-substitution initiation procedure. The second group received abbreviated initiation consisting of one-session exposure to each ethanol/sucrose combination used in standard initiation. The animals were then provided with 23 h/day access to ethanol (10%, v/v) from a retractable drinking tube. Food pellets were available following a single-lever press, and water was available from a sipper tube. After 5 weeks, the data indicated that few significant differences existed between the groups on total ethanol (g/kg), food or water consumed. The overall intake (g/kg/day), number of ethanol bouts per day, and amount consumed per bout (g/kg/bout) were substantially lower than observed in previous research using ethanol presented in a dipper. However, differences in g/kg per ethanol bout did differ significantly between the two groups with the group receiving standard initiation showing more ethanol consumed per bout. These data agree with our previous work indicating that initiation results in larger drinking bouts.     

Alcohol inhibition of suckling-induced prolactin release in lactating rats: threshold evaluation

Prolactin release in response to suckling was examined in primiparous lactating rats two hours after alcohol administration. Litters were adjusted to eight pups on lactation day 2 and dams were implanted with an atrial catheter on day 6. On day 10, pups were separated from the mother at 0800 h. An extension was attached to the catheter at 1100 h. Following removal of a baseline blood sample an hour later, rats were infused with alcohol doses of 0, 0.5, 1.0, 2.0 or 2.5 g/kg body weight. Two hours later, pups were returned to dams. Subsequent blood samples were obtained 10, 30, 60, 120 and 180 min after the onset of suckling. Following 10 min of suckling, plasma prolactin for groups of rats infused with alcohol at 2.0 and 2.5 g/kg body weight were lower than control, 0.5 and 1.0 g/kg groups. The blood alcohol level (BAL) for the 2.0 g/kg group was 94 +/- 8 mg% and for the 2.5 g/kg group was 162 +/- 4 mg%. After 30 min, the BAL for the 2.5 g/kg group was 134 +/- 5 mg% and plasma prolactin was suppressed in this group compared to control, 0.5 and 1.0 g/kg groups. The BAL for the 2.0 g/kg group after 30 min of suckling was 74 +/- 9 mg% but prolactin was not significantly lower than controls. We conclude that in rats, alcohol inhibition of suckling-induced prolactin release is directly correlated to the BAL. The threshold BAL which effectively inhibits this prolactin release is lower than the human legal intoxication level.     

高效液相色谱-荧光法检测富含淀粉和糖类药材中黄曲霉毒素的研究

[目的]采用免疫亲和净化手段和液相色谱检测技术,建立富含淀粉、糖类药材中黄曲霉毒素(AF)的测定方法,为福建地产中药材AF的检测和污染调查提供技术支撑。[方法]样品粉末经80%甲醇高速均质提取,用免疫亲和柱(IAC)净化,用HPLC测定,C18反相色谱柱分离,荧光检测器(FLD)测定。[结果]4种AF的最低检出浓度0.02～0.10μg/kg,定量限0.08～0.4μg/kg;以太子参等为加标基质,加标水平为6～24μg/kg(AF总量),AF平均回收率68.7%～113.0%,RSD为1.4%～13.7%。[结论]富含淀粉、糖类药材样品AF含量可用HPLC-FLD测定,准确度高、精密度好,满足欧盟对食品饲料中AF检测的要求。     

Effect of methionine supplementation of a soy protein isolate on short-term nitrogen balance in young women

The effect of L-methionine supplementation on the utilization of a soy protein isolate (SPI) was evaluated by short-term nitrogen balance studies in young women. Thirteen female students were given SPI in an initial period and SPI supplemented with 1% methionine in a second period immediately after menstruation as the sole source of protein. After one day on protein-free diet, each subject received conventional low-protein diet for three days, and then low protein, semisynthetic diet containing 0.5 g/kg/day (seven subjects) or 0.3 g/kg/day (six subjects) of SPI or SPI supplemented with methionine for seven days. The energy intake was approximately of a maintenance level of 36.5 +/- 3.8 kcal/kg/day. The mean N balances of the subjects at an intake level of 0.5 g/kg/day in the SPI period and methionine supplemented period were -6.2 +/- 12.6 mg N/kg and -9.8 +/- 9.8 mg N/kg, respectively, while their N balances at an intake level of 0.3 g/kg/day were -17.8 +/- 7.2 mg N/kg in the SPI period and -15.5 +/- 3.0 mg N/kg in the methionine supplemented period. There was no significant difference between the values in the SPI and methionine supplemented periods at both levels of protein intake. Blood analyses were carried out before and after the SPI period and after the period of methionine supplementation. The urinary creatinine and urea excretions during these periods were not markedly affected.     

Dietary docosahexaenoic acid levels influence the outcome of arabinosylcytosine chemotherapy in L1210 leukemic mice

The purpose of this study was to investigate whether dietary supplementation with the n-3 fatty acid docosahexaenoic acid (DHA) in combination with arabinosylcytosine (AraC) chemotherapy could prolong the life expectancy of mice bearing L1210 leukemia. The four control diets included rodent chow, a diet containing 5% of a blended oil mimicking the fatty acid composition of rodent chow, and diets containing 5% or 10% fat with safflower oil as the main oil source. The two DHA-supplemented diets provided 1.5% or 3.5% DHA and 5% or 10% total fat, respectively. After tumor cell inoculation, mice were treated with AraC for 10 days. Mice fed the 5% safflower oil diet (30.1 -/+ 4.1 days), but not those fed the 10% safflower oil diet, survived longer than the chow-fed animals (22.1 -/+ 3.1 days, P = 0.05). The 1.5%-/+ DHA diet (average intake 1.8 g DHA/kg/day) was associated with a longer life span (33.3 -/+ 3.4 days, P < 0.01 vs. chow-fed) and no incidence of death due to drug toxicity. Further increasing DHA intake (4.5 g DHA/kg/day) resulted in shortened survival time (26.5 -/+ 2.0 days), increased circulating tumor cell burden, and lowered red blood cell concentrations. These data suggest that a modest level of dietary DHA or linoleic acid supplementation may improve the antineoplastic efficacy of AraC. However, overconsumption of DHA reverses the beneficial effect of DHA intake on drug sensitivity.     

Nitrogen and energy balance in septic and injured intensive care patients: response to parenteral nutrition

We studied energy and nitrogen balance in 50 intensive care patients with sepsis (n = 18) or multiple trauma (n = 32). Most patients were mechanically ventilated during the study. Within 72h of admission the patients were randomised to receive one of 5 infusion regimens for 48h (group n = 9-11). The control group received hypocaloric glucose, two groups received 1.5g/kg/day of amino-acids, either with hypocaloric glucose on both days or with energy adjusted to pre-nutrition REE on the second day. The fourth group received 0.6g/kg/day of amino-acids and energy at REE, and the fifth group a high nitrogen (18g/day) regimen with a stepwise increase in energy intake from day 1 to day 2. Baseline REE was 118 +/- 18.9% of predicted. No significant differences in REE were observed between the diagnostic groups, treatments or measurements performed during mechanical or spontaneous ventilation. Nitrogen balance in the control group was -250.3 +/- 83.3 mg/kg on day 1 and 218.6 +/- 95.3 mg/kg on day 2. Nitrogen balance remained negative in all groups throughout the study (range of group means-218.6 to -48.5 mg/kg/day). Increasing energy intake equal to prenutrition REE at an amino-acid dosage of 1.5g/kg/day decreased the negative nitrogen balance by 66%. Further increase in energy balance had only a marginal effect on nitrogen balance.     

The available niacin values of foods for rats and their relation to analytical values

A bioassay for niacin was developed using weight gain or "gain/food eaten" of young rats as the response measure. The best basal diet contained casein 70 and gelatin 65.5 g/kg together with supplementary tryptophan to a total of 0.97 g/kg and other amino acids to meet requirements. After a 4-day depletion period, rats gained ca. 1 g/day over the next 20 days on the basal diet alone, or ca. 7 g/day and 12 mg/kg added nicotinic acid. Test foods were added at two levels with diets adjusted to keep constant amino acid composition. The results were compared with chemical analyses for total niacin (i.e., in extracts prepared from samples digested with alkali) and for free niacin (using extracts made at neutral pH) with separation of nicotinic acid and nicotinamide on thin-layer chromatograms or Sephadex columns. Eight samples of mature cooked cereals, with their niacin largely in bound forms, gave rat assay values equivalent to ca. 35% of their total niacin content. Alkali-cooked tortilas, steamed sweet corn, beans and liver, with their niacin all in free form, gave assay values close to their total niacin content. Baked potatoes and peanut flour were intermediate in both respects.