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1.
The stepwise Fenton oxidation process, in which hydrogen peroxide (H2O2) is added in a step-by-step manner instead of at the beginning, can achieve better sorbed crude oil removal effects. The results showed that if a high ratio of sorbed total petroleum hydrocarbon (TPH) was present in soil samples S1 (100%, initial TPH: 10,009 mg/kg) and S2 (94.2%, initial TPH: 4850 mg/kg), the TPH was oxidized in each step. In addition, the total TPH removal efficiency was 49.6% compared with the 27.9% achieved in conventional Fenton oxidation in which all H2O2 was added at the beginning. Nevertheless, when the ratio of sorbed TPH in the soil sample S3 was low (45.3%, initial TPH: 2850 mg/kg), the TPH removal efficiency was 18.9%, which was slightly higher than 18.2% achieved in the conventional Fenton process because if the sorbed TPH concentration was low, the sorbed TPH was mainly removed in the first step. The second and the third step resulted in long-chain alkanes entering the aqueous phase rather than removing them from the soil, which posed environmental risk. Therefore, it is clear that stepwise Fenton oxidation could improve sorbed TPH removal efficiency when the sorbed TPH concentration in the soil is high.  相似文献   

2.
Feeding trials were conducted on seven subadult giant pandas (1.5–4.7 years old). The giant pandas consumed diets with 20 various levels of crude protein (CP): 132.9, 186.8, 206.0, 233.1, 251.4, 255.2, 288.5, 290.8, 299.1, 334.6, 370.7, 378.7, 379.9, 399.2, 372.6, 411.4, 436.1, 484.4, 509.3, and 563.7 g/day. According to the differences in the body weight (BW) gain (weight/month (W/M)) and the amounts of ingested CP, subadult giant pandas are divided into at least three age groups: 1.5–2.0, 2.5–3.9, and 4.0–4.7 years. Although there apparently is no direct relationship between the ΔW/M and the CP consumed by all the giant pandas, a linear relationship existed between the square root of CP ingested (g) per unit BW (W0.75, Kg) and weight gain per month (ΔW/M, Kg/M) of giant pandas aged 1.5–2.0 years. No such relationship existed in the giant pandas aged 2.5–4.7 years, but ΔW/M decreased with the increasing CP per unit gross energy (GE) consumed (CP/GE). For the 1.5–2.0‐year‐old giant pandas, CP for maintenance was determined at 3.6576 g/Kg W0.75/day when ΔW/M was 0, and CP for growth was 1.7541 g/Kg W0.75/day when ΔW/M was equal to 1 Kg/M; thus, suitable intake of total CP is 9.95 g/Kg W0.75/day. The average value of ingested CP was 13.54 ± 3.01 g/KgW0.75/day for 2.5–3.9‐year‐old pandas, and 12.25 g/KgW0.75/day for 4.5–4.7‐year‐old pandas. Zoo Biol 21:223–232, 2002. © 2002 Wiley‐Liss, Inc.  相似文献   

3.
Food selection in folivorous primates has been hypothesized to be correlated with leaf chemistry. To test this hypothesis, we conducted a 5-month study on Presbytis entellusin a moist deciduous forest in the Rajaji National Park,Uttar Pradesh, India. The study period covered two seasons, winter and spring. We used the percentage time spent feeding on each food item as an index of food selection, which we estimated from group scan data collected from one study group for 6 days each month. We estimated the selection ratio for each item as the ratio of time spent feeding to availability. We estimated food availability from vegetation sampling and phenological data in the home range of the study group. We estimated crude protein (CP), acid detergent fiber (ADF) and tannins in mature and young leaves of 12 major food species in the laboratory. Food selection is positively correlated with CP in winter and negatively correlated with ADF in both seasons. It also is correlated with CPJADF ratio, but to a lesser extent than the best predictor in winter and spring. Selection ratio is not correlated with CP and ADF in both seasons. It is probable that the inclusion of other factors, such as micronutrients,condensed tannins, and digestibility, might give a better prediction of food selection.  相似文献   

4.
选取不同体质量的秦巴山区野生多鳞白甲鱼(Onychostoma macrolepis)20尾,对其肌肉中的常规营养成分、氨基酸和脂肪酸以及微量元素硒的含量进行检测和分析,以期对多鳞白甲鱼的营养价值进行评估。研究结果显示:秦巴山区野生多鳞白甲鱼的粗蛋白和粗脂肪含量分别为17. 37%和1. 76%。谷氨酸含量最高,天冬氨酸和赖氨酸次之,蛋氨酸含量最低,鲜味氨基酸和必需氨基酸分别占氨基酸总量的38. 46%和37. 10%,氨基酸评价指数(EAAI)为77. 00%。野生多鳞白甲鱼二十二碳六烯酸(DHA)和二十碳五烯酸(EPA)的总量为6. 32%,饱和脂肪酸(SFA)和不饱和脂肪酸的比值约为1∶1。肌肉中硒的含量为(0. 058±0. 017)mg/kg。研究结果表明,秦巴山区野生多鳞白甲鱼的营养价值较高,硒含量适中,可以在当地进行进一步产业化开发和推广。  相似文献   

5.
从采白成都市郊森林的土壤中分离纯化到二株粘细菌CS262和CS211。二株粘细菌在琼脂平板上表现出相互抑制子实体发育的拮抗作用。CS211菌株对蜡状芽孢杆菌,藤黄八叠球菌,枯草芽孢杆菌,金黄色葡萄球菌具有很强的抑制作用。采用非极性大孔树脂吸附和TIC方法对抗菌活性物质作了初步研究。  相似文献   

6.
中国西南地区乌头类中草药的生药学研究   总被引:1,自引:0,他引:1  
西南地区乌头类中草药种类很多,块根外形近似,但它们间毒性相差较大。本文对16种乌头的根进行形态组织比较,指出鉴定特征,并附组织图及成分、使用情况比较表。  相似文献   

7.
葡萄皮中粗蛋白提取条件的研究   总被引:1,自引:0,他引:1  
利用葡萄饮料厂生产的废料葡萄皮提取粗蛋白,并对影响粗蛋白提取率的几个因素进行了研究。这些因素包括提取溶剂的选择、提取剂浓度、提取温度、提取时间等,并设计正交实验选取最佳提取条件,即:以NaOH溶液为提取剂,NaOH浓度为0.8 mol·L-1,提取温度70℃,提取时间为80min。提取得到的粗蛋白中蛋白质质量分数为71.38%。  相似文献   

8.
本文阐述了现代道地中药材的概念演变,道地中药材是经过千百年来的疗效认证而普遍得到人们认可的优质中药材。通过对中药材栽培历史的分析,本文认为道地中药材的优质性主要来自野生资源。多数中药栽培发展较晚,栽培生产技术与环境结合尚未达到最优化的程度。从道地中药材成因的角度分析,野生中药材在生长年限、种质、生境、性状、成份等各方面与栽培中药材都与明显的差异,其质量也一定不同,因此对栽培中药材的道地性的应有待于进一步认识。同时,通过将现代栽培技术与中药材栽培相结合,会对栽培中药材的质量稳定和提高发挥重要作用。  相似文献   

9.
Abstract

Crude glycerol is becoming a financial and environmental liability due to its surplus production from biodiesel industry, and its utilization as a fermentation feedstock for value-added chemicals production has been widely studied. In present work, the capacity of an endophytic fungus, Chaetomium globosum CGMCC 6882, using glycerol and crude glycerol for polysaccharide production was investigated. Results showed that the polysaccharide titers from glucose and glycerol were 1.85 and 3.8?g/L, respectively. Moreover, spore morphology of C. globosum CGMCC 6882 was favorable for polysaccharide production. Meanwhile, impurities in crude glycerol have no effect on polysaccharide production by C. globosum CGMCC 6882. Finally, characteristic results of polysaccharides produced from glucose, glycerol, and crude glycerol have suggested that metabolic flux might be a determinant factor on polysaccharide structure. Taken together, this research provided an innovative approach of utilizing crude glycerol produced from the biodiesel production process.  相似文献   

10.
Summary Enrichment cultures from oil-contaminated beach material from Prince William Sound, Alaska, generated both a mixed bacterial community of indigenous, oil-degrading marine microorganisms and a pure culture oil-degrader, strain EI2V. The mixed and axenic cultures were used in comparative shake flask studies of inoculation on biodegradation of Prudhoe Bay crude oil. Within 12 h following inoculation of homogenized, oiled beach material with the mixed culture, total CO2 production was increased 2-fold relative to a noninoculated control. Moreover, measurements of phenanthrene degradation (as determined by the release of14CO2 from [9-14C]phenanthrene) showed a 2-or 3-fold greater degradation when inoculated with either strain EI2V or with the mixed culture, respectively. However, as medium was replaced by a simulated tidal cycle, the observed stimulation of CO2 production decreased, and the addition of strain EI2V had no greater effect on total CO2 production than the addition of inorganic nutrients alone. Chemical analysis of oil recovered after 7 days incubation also suggested that, while these cultures are capable of efficient biodegradation of Prudhoe Bay crude in liquid culture, inoculation of beach material with high numbers of these microorganisms had little effect on the rate and extent of biodegradation of weathered crude oil. Overall, the sustained stimulatory effect was no greater than that observed with the addition of inorganic nutrients alone.  相似文献   

11.
A “crude plastid” preparation from young pea leaves converts linoleate [1-14C] or [U-14C] (ammonium salt or free acid) into a C12 dibasic acid with a double bond at Δ9.  相似文献   

12.
Research on feasible methods for the enhancement of bioremediation in soil contaminated by crude oil is vital in oil-exporting countries such as Kuwait, where crude oil is a major pollutant and the environment is hostile to biodegradation. This study investigated the possibility of enhancing crude oil bioremediation by supplementing soil with cost-effective organic materials derived from two widespread locally grown trees, Conocarpus and Tamarix. Amendments in soils increased the counts of soil microbiota by up to 98% and enhanced their activity by up to 95.5%. The increase in the biodegradation of crude oil (75%) and high levels of alkB expression substantiated the efficiency of the proposed amendment technology for the bioremediation of hydrocarbon-contaminated sites. The identification of crude-oil-degrading bacteria revealed the dominance of the genus Microbacterium (39.6%), Sphingopyxis soli (19.3%), and Bordetella petrii (19.6%) in unamended, Conocarpus-amended, and Tamarix-amended contaminated soils, respectively. Although soil amendments favored the growth of Gram-negative bacteria and reduced bacterial diversity, the structures of bacterial communities were not significantly altered.  相似文献   

13.
毛木耳漆酶纯化及其部分漆酶特性的研究   总被引:7,自引:1,他引:6  
对毛木耳AuriculariapolytrichaAP4的粗酶液进行PAGE电泳后发现含有三种漆酶同工酶,并且通过运用NativeSDS-PAGE获得三种漆酶的分子量大小分别约为:LacA(110kD);LacB(84kD);LacC(65kD)。对漆酶粗酶液通过硫酸铵分级沉淀和离子交换柱层析进行纯化,用SDS-PAGE证明获得纯化的单一漆酶LacB。LacB漆酶的反应的最适温度为30℃,最适pH为3.0。此酶氧化ABTS的Km值为6.64×10-mmol/L,金属离子对酶活的影响很大,其中5Ca2+,Mg2+,Zn2+,Na2+,Ag2+对漆酶LacB有明显的激活作用;Co2+,Hg2+,Fe3+,Fe2+,Ba2+等对酶活有明显的抑制作用。LacB和其它真菌漆酶一样具有底物专一性不强的特点,并且LacB对RB亮兰染料有很好的脱色作用。  相似文献   

14.
为明确核桃(Juglans regia L.)种仁中粗蛋白质和粗脂肪含量的遗传特性,分别对品种‘元林’(母本)和‘青林’(父本)及其杂交后代群体种仁的粗蛋白质和粗脂肪含量及其遗传参数进行了测定及分析;并在此基础上,比较分析了15个优选单株种仁的粗蛋白质和粗脂肪含量以及种仁油的脂肪酸组成.结果显示:‘元林’和‘青林’及其杂交后代群体种仁中粗蛋白质含量均值分别为17.61%、19.28%和19.70%,变异系数分别为4.25%、7.99%和18.75%;粗脂肪含量均值分别为61.03%、59.28%和57.61%,变异系数分别为10.54%、4.93%和9.56%.杂交后代群体种仁的粗蛋白质及粗脂肪含量的各遗传参数均有较大差异;单株间粗蛋白质含量差异极显著(P≤0.01),遗传力(H2)和相对遗传增益(△G’)分别为0.93和33.12%;粗脂肪含量差异显著(P≤0.05),H2和△G’分别为0.92和19.06%.15个优选单株种仁的粗蛋白质和粗脂肪含量分别为15.78% ~25.22%和50.41% ~64.69%,其中,单株6-7、5-19和3-19的粗蛋白质和粗脂肪含量均较高.优选单株种仁油由亚油酸、油酸、α-亚麻酸、棕榈酸、硬脂酸、顺-11-二十碳烯酸和花生酸组成,以亚油酸相对含量最高(61.57%),不饱和脂肪酸总相对含量达87.48%.研究结果表明:与亲本相比,核桃杂交后代种仁的粗蛋白质含量较高、粗脂肪含量较低;对杂交后代进行优良单株筛选可获得粗蛋白质和粗脂肪含量较高的遗传增益.  相似文献   

15.
黑木耳漆酶纯化的研究   总被引:1,自引:1,他引:0  
目的:研究黑木耳(Auricularia auricula)“黑29”的漆酶纯化,为进一步酶学性质的开展、酶应用和酶基因克隆提供理论基础。方法:采用硫酸铵分级沉淀和柱层析技术分离蛋白,通过PAGE和SDS-PAGE电泳检测蛋白。结果:SDS-PAGE电泳检测发现粗酶液含三种漆酶,分子量大小分别为LacA(60kD)、LacB(34kD)、LacC(19kD);纯化后获得纯化的单一漆酶LacA、LacC组分。结论:得漆酶两个单一组分,为进一步漆酶研究奠定基础。  相似文献   

16.
朱砂七粗多糖的提取及生物活性的研究   总被引:1,自引:0,他引:1  
首次从朱砂七中提取粗多糖(PCCP),研究了PCCP对.OH自由基、O2-.自由基和DPPH.自由基的清除能力以及抗脂质过氧化能力,选用人肝癌细胞HepG2,经MTT染色法研究其体外抗肿瘤活性。结果显示,PC-CP的浓度在8.48 mg/mL时,对.OH、O2-.和DPPH.的清除率分别达到了52.3%、54.7%和38.3%;PCCP的浓度在8.48 mg/mL时,对脂质过氧化的抑制率达到了62.0%;PCCP的浓度在277.78μg/mL时,对人肝癌细胞HepG2的抑制率达到了42.6%,表明PCCP具有一定的体外抗氧化能力和体外抗肿瘤活性。  相似文献   

17.
An in vitro incubation technique based on the first stage of the in vitro digestion technique published by Tilley and Terry (1963) was developed to estimate the utilizable crude protein (uCP) of single feeds and feed mixtures as non ammonia‐N after 24 h of incubation. The results of 25 feed samples showed that there was a significant relationship between the uCP values calculated by regression based on in vivo data sets (Y, CP [g‐kg‐1 DM]) and those measured by the in vitro incubation technique (X, CP [g‐kg‐1 DM], 24 h incubation):

y=0.85x+18.0, r2=0.84, P≤0.001.

It was concluded that it can be possible to determine the uCP value of single feeds or feed mixtures by this in vitro incubation technique and to estimate the uCP value of feeds by this regression equation.  相似文献   

18.
台湾乳白蚁跟踪信息素粗提物活性与应用研究   总被引:6,自引:0,他引:6  
台湾乳白蚁是我国为害最凶的一种白蚁。对它的防治早就引起国内外白蚁工作者的广泛重视。目前越来越多的做法是将“诱”与“杀”两个步骤合二为一。也有许多学者已将白蚁的跟踪信息素用于白蚁的诱集上作了研究。本文介绍了台湾乳白蚁跟踪信息素粗提物生物活性,包含信息素的提取、跟踪反应、引诱效应、感受距离测定,以及在台湾乳白蚁防治上的实际应用等。  相似文献   

19.
为了更好的开发和利用日本臭菘资源,对日本臭菘各组织的氨基酸和粗蛋白含量进行了测定。结果显示,日本臭菘花、叶和根的氨基酸总含量分别为16.23%、19.45%、12.46%;日本臭菘花、叶、根中粗蛋白含量分别为25.32%、27.10%、17.78%。结果表明,日本臭菘叶中的粗蛋白总含量和氨基酸含量最高,根中的粗蛋白含量和氨基酸含量最低。  相似文献   

20.
In the past five decades, agricultural pests are controlled by synthetic pesticides which caused ill effects on non-target organisms and environment; also insect pests developed resistance and minor pests became major pests. By keeping this in mind, the present study was selected. Antifeedant and larvicidal activities and growth inhibitory effects of hexane, chloroform and ethyl acetate leaf extracts of Fleuggea leucopyrus (Koen.) Willd. against Helicoverpa armigera (Hbn.) were studied. Antifeedant and larvicidal activities were evaluated at 0.5, 1, 2.5 and 5% concentrations at laboratory conditions. Hexane and chloroform extracts at 5% concentration recorded significant antifeedant activity of 82.41 and 74.45%, respectively. Hexane extract recorded the least LC50 and LC90 values of 1.37 and 4.80%, respectively. Hexane extract recorded maximum larvicidal activity of 85.78% with LC50 and LC90 values of 1.69 and 4.94%, respectively. Ethyl acetate extract also had notable amount of larvicidal activity of 81.77% at 5% concentration. Hexane extract at 5 and 2.5% and ethyl acetate extract at 5% concentrations completely prevented the adult emergence of H. armigera. This plant could be further exploited to identify the active principle(s) responsible for the activities and to develop a novel pesticidal formulation. This is the first report of F. leucopyrus is studied for its bioefficacy against H. armigera.  相似文献   

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