产复合酶优良菌株筛选及苹果渣固态发酵效果研究

通过液态发酵产酶试验和苹果渣固态发酵试验,研究不同丝状真菌产水解酶的活性及产酶优良的霉菌对苹果渣发酵的改质效果,筛选出适用于苹果渣发酵的优良霉菌。结果表明,黑曲霉MHQ1产纤维素酶、果胶酶和木聚糖酶的活性较高,分别为64.7、66.9和216.7U·mL~(-1);米曲霉MMQ1产淀粉酶和蛋白酶的活性较高,分别为1 782.6和83.0U·mL~(-1);烟曲霉MYQ1产蛋白酶和果胶酶的活性较高,分别为128.9和51.6U·mL~(-1)。其中,黑曲霉MHQ1能在果渣基质上良好地生长,对果渣具有较强的降解改质能力,产物中粗蛋白和纯蛋白质量分数分别增至387.5和228.9g·kg~(-1),接菌增率为79.2%和193.8%,且纤维素酶、果胶酶和蛋白酶的活性分别为178.0、150.6和57.5U·g~(-1),纤维素、果胶分别降解28.9%、53.8%,水溶性氨基酸质量分数增至2.7%。采用酵母菌与产复合酶优良的霉菌复合发酵,能显著提高果渣发酵产物中的蛋白质水平,降低抗营养物质的质量分数,提高水解酶和水溶性氨基酸等活性物质的质量分数,有效地发酵果渣为生物蛋白饲料。     

Suitable condition of enzymatic reactivity for determining the digestibility of feedstuffs phosphorus in vitro by dialysis tube method

In order to develop a new method for determining the phosphorus (P) digestibility in vitro in feedstuffs by dialysis tube, a L₃₂(4⁹) orthogonal experiment with eight factors (4 levels for each factor) and a single factor experiment on the enzymatic reactivity were carried out. The sequence of significance of the eight factors on sample-P dialyzability was as follows: trypsin digestion for 6 h, dialyzing solution at 100 mL, pH of pepsin solution at 2.5, pepsin concentration at 2000 U·mL⁻¹ pepsin digestion for 100 min, at temperature of 35°C, trypsin concentration at 1625 U·mL⁻¹, and pH of trypsin solution at 6.5, respectively. And in vitro dialyzabilities of P in soybean meal, barley, sorghum, peanut meal, and rapeseed meal were (36.91 ± 0.58)%, (27.28 ± 0.94)%, (26.95 ± 0.58)%, (30.51 ± 0.83)%, and (20.82 ± 1.09)%, respectively. __________ Translated from Journal of South China Agricultural University, 2007, 28(3): 85–89 [译自: 华南农业大学学报]     

建鲤体内外急性肝损伤模型的建立

以四氯化碳(CCl4)为肝毒剂,建立建鲤体内外急性肝损伤模型.体内,采用腹腔注射法造模,按0.1 mL/10g一次性分别注射0、6.25％、12.5％和15％ CCl4-橄榄油溶液(v/v),于造模后24 ～ 144 h取血,测定建鲤血清中谷丙转氨酶(GPT)、谷草转氨酶(GOT)、乳酸脱氢酶(LDH)和丙二醛(MDA)水平;体外,0、2、4、8、16、32 mmol·L-1 CCl4分别作用于原代培养的建鲤肝细胞4h后,用噻唑蓝(MTT)法检测细胞生存状况,同时收集细胞培养上清,测定其GPT、GOT、LDH、MDA、超氧化物歧化酶(SOD)和谷胱甘肽(GSH)活力.结果显示,12.5％、15％ CCl4-橄榄油溶液腹腔注射建鲤24 h后即能引起血清中GOT、GPT和MDA显著升高,15％ CCl4溶液造模组48 h能显著提高血清中LDH水平,4个指标均在CC14作用96 h后恢复到接近正常水平;8～ 32 mmol·L1 CCl4作用体外培养肝细胞4h时,细胞上清中GPT、GOT、LDH和MDA含量显著升高、SOD和GSH活力显著下降,肝细胞存活率显著下降,分别为空白对照组的66.29％、54％和37％且有剂量依赖性.结果表明,分别采用15％ CCl4-橄榄油腹腔注射建鲤72 h和8 mmol·L-1 CCl4作用体外培养肝细胞4h可以构建体内外急性肝损伤模型.     

木质素降解细菌的筛选及园林废弃物降解研究

为获得能够高效降解园林废弃物的细菌,采用苯胺蓝和愈创木酚平板法从高温期堆肥中初筛得到木质素降解酶活力较高的菌株,再利用筛选出的菌株进行液态产酶和固态发酵试验,对漆酶(Lac)、锰过氧化物酶(MnP)和木质素过氧化物酶(LiP)的活力变化及菌株对园林废弃物的降解率进行测定。结果表明,从高温期堆肥中初筛得到3株木质素降解酶活力较高的细菌L-9、L-12和L~(-1)7;液态产酶试验测得L-9、L-12和L~(-1)7的Lac活力分别为8.61、12.26和2.20 U·mL~(-1);Mn P活力分别为11.16、14.75和16.24 U·mL~(-1);LiP活力分别为40.48、42.41和37.52 U·mL~(-1);固态发酵试验测得接种L-9、L-12和L~(-1)7菌株28 d后,园林废弃物的木质素降解率分别为14.88%、20.10%和11.25%;纤维素降解率分别为25.64%、28.47%和30.03%。综合评价菌株L-12具有较强的木质素降解能力,通过形态观察和16Sr DNA序列分析,将L-12鉴定为嗜热嗜脂肪地芽孢杆菌(Geobacillusstearothermophilus),可用于探究细菌降解木质素原理和工业化生产木质素降解菌剂。     

Research on Yucca schidigera extract feeding on the rumen ecology, protozoal populations and serum chemistries of sheep

In a completely randomized block design experiment, 16 ruminally cannulated male sheep with body weights of (40 ± 2.1) kg were fed twice daily (8:00 and 16:00) with concentrate and forage (50:50 on dry matter (DM) basis). Dietary treatments were supplemented with intraruminal doses of powdered Yucca schidigera extract (YSE) at the levels of 0 (control), 100, 200 and 300 mg · kg⁻¹. On days of 15, 16 and 17 after feeding, ruminal content was sampled at 0, 2, 4, 6 and 8 h after dosing (8:00), and blood samples were collected at the end of experiment (the days 18 and 19 after feeding). Results showed that the treatment groups’ acidity was not affected (P = 0.13) by YSE. Comparing to the control, the ruminal propionate concentration was increased by YSE addition in a dose-dependent manner by up to 29.8% (P < 0.05), and the acetic concentration was decreased by up to 17.5% (P < 0.05). The ruminal ammonia concentration 2 hours after feeding was higher (P < 0.05) in sheep fed without YSE (increased by 17.57 mg· 100 mL⁻¹) than those fed with YSE at 200 mg · kg⁻¹ (6.77 mg · 100 mL⁻¹ increase in NH₃) and at 300 mg · kg⁻¹ (6.50 mg· 100 mL⁻¹ increase in NH₃). Protozoal populations in the rumen were lower (P < 0.05) with the YSE feeding dose at 300 mg · kg⁻¹ than the control. The serum chemistries were not different among treatments (P > 0.05) and were within the normal physiological ranges for sheep 19 days after feeding. The study indicated that 200 mg· kg⁻¹ and 300 mg· kg⁻¹ YSE groups had particular suppressing effects on ruminal ammonia concentration, ammonia-N concentrations and protozoal populations. The effect of YSE on ruminal fermentation could be attributed to the selective inhibitory effect on rumen microbial species. High level (300 mg · kg⁻¹) YSE as feed additives resulted no negative impact on sheep in our tests.     

Effects of prey density on the growth and survival of hybrid snakehead larvae

The effects of prey density (0.1, 0.3, 1, 3 and 10 prey·mL⁻¹) on the growth and survival of hybrid snakehead (Channa argus × C. maculate) larvae were investigated. The larvae were divided into three groups with different body lengths of 0.68 cm, 1.50 cm and 3.20 cm, respectively. The growth of the hybrid snakehead larvae in all three groups increased with prey density increasing from 0.1 to 1 prey·mL⁻¹. The specific growth rate (SGR) was the highest when the prey density was 1 prey·mL⁻¹. When prey density was higher than 1 prey·mL⁻¹, SGR of larvae in Group I (the larvae of early development stage) decreased, while no significant change was observed in those of Group II and Group III. The survival rates of hybrid snakehead larvae in all three groups were high (91.11%–100%) and not significantly affected by the prey densities except in Group I with the highest prey density (10.0 prey·mL⁻¹) which was significantly lower than the others. Body size was not sensitive to prey density. The optimum prey density was confirmed at 1 prey·mL⁻¹ in all the treatments. __________ Translated from Journal of Huazhong Agricultural University, 2007, 26(3): 367–370 [译自: 华中农业大学学报]     

热泉土壤来源的纤维素降解菌的分离与初步鉴定

通过富集培养方法,从5份热泉土壤中筛选得到6株具有羧甲基纤维素(CMC)降解活性的菌株。采用原核生物保守16S r RNA核糖体基因序列分析,发现它们分别隶属于假单胞菌属、芽孢杆菌属和类芽孢杆菌属。在此基础上,对6株纤维素降解菌的生长温度、pH值、抗生素敏感性、盐离子耐受性以及羧甲基纤维素酶(CMCase)活力做了初步研究。结果表明,芽孢杆菌属的菌株WP-6和WP-3的CMCase活力最强,胞内酶活力最高达72.0 U·m L~(-1),假单胞菌株WP-2的CMCase活力最弱,胞内外酶活力均小于5.0 U·m L~(-1)。生理学结果显示,6个降解菌株都具有嗜热特点及不同程度的耐盐特性,给后续高温及盐离子耐受性纤维素酶开发提供了较好的材料。     

固定化三唑酮降解菌球的性能表征及水体污染修复效应

以课题组保藏的一株三唑酮高效降解菌Stenotrophomonas maltophilia（命名为SM3）为目标菌株，以海藻酸钠-聚乙烯醇-活性炭为复合载体进行包埋法制得固定化菌球（PSC-SM3），优化固定化菌球制备条件，对其性能进行表征测定，并评价其投加于不同水体中对三唑酮的实际去除效果。结果表明：c（PVA）为6%，c（SA）为1.5%，c（AC）为2.5%，c（CaCl₂）为1.5%，包菌量为0.02 g·mL^-1时，PSC-SM3对三唑酮的去除效果最佳；扫描电镜、傅立叶红外光谱、机械强度、弹性系数和储存稳定性的测定结果均表明固定化菌球PSC-SM3具备良好的性能；在供试浓度1、2、5和10 g·mL^-1的三唑酮污染水体中作用14 d后，PSC-SM3在工业废水中对三唑酮的降解率在50.08%～54.07%之间，在生活污水中对三唑酮的降解率在40.94%～57.55%之间，在农田灌溉水中对三唑酮的降解率在44.83%～57.02%之间。相比于游离菌株，PSC-SM3的修复效果更具有实际应用意义。     

华北驼绒藜和四翅滨藜对干旱胁迫的生理反应

为研究引种小灌木在干旱胁迫下的生理光合特性,以1a生华北驼绒藜、四翅滨藜2种扦插苗为试验材料,研究土壤水分[土壤水分为田间持水量的85%~90%(CK)、65%~70%(T_1)、50%~55%(T_2)和35%~40%(T_3)]对2种灌木光合生理指标的影响。结果表明:随着水分胁迫程度的增加,2种灌木根冠比、电解质外渗率呈现CKT_1T_2T_3的变化规律;丙二醛质量摩尔浓度与CK相比,各水平下均显著增加,且都在T_2水平下达最大;过氧化物酶活性在T_1水平下达到最大,分别为340.83U·mg~(-1)·min~(-1)、862.93U·mg~(-1)·min~(-1);在T_2水平下,四翅滨藜脯氨酸质量分数较CK增加28倍;华北驼绒藜叶片蒸腾速率(T_r)、净光合速率(P_n)均呈现出CKT_1T_2T_3的变化特征;在T_1水平下,四翅滨藜叶绿体色素(叶绿素a、叶绿素b及类胡萝卜素)增加,光合能力增强。     

Effect of extracts of Chinese pine on its own seed germination and seedling growth

The allelopathic potential of Chinese pine (Pinus tabulaeformis Carr.) against its own seed germination and seedling growth was tested with aqueous extracts (0.01, 0.02, 0.05, and 0.10 g·mL⁻¹) obtained from different organs (roots and litter needles) at different individual ages (12, 52, and 110 years old). The results showed that root and litter extracts had different effects on seed germination and seedling growth, and the effects varied with the concentrations, the organs, and the tree age of extracts. The strongest stimulatory effect on seed germination of Chinese pine was exposed to 0.02 g·mL⁻¹ root extract from the 110 years old Chinese pine trees and exposed to 0.02 g·mL⁻¹ litter extract from the 12 years old Chinese pine trees. Meanwhile, the strongest stimulatory effect on growth of Chinese pine seedlings was exposed not only to 0.01 g·mL⁻¹ root extracts from the 110 years old Chinese pine but also to 0.01 g·mL⁻¹ litter extract from the 12 years old Chinese pine. The promoting effect of the extracts of root on seed germination and seedling growth increased in the order of 12, 52, and 110 years old. The promoting effect of the extracts of litter on seed germination and seedling growth increased in the order of 110, 52, and 12 years old. Our results suggested that litter leachates or root exudates of Chinese pine may influence the natural regeneration within Chinese pine stands via the release of allelochemicals into the environment.     

氮素水平对宽杆芥菜幼苗生长及酶活性的影响

以NH4NO3作为变量,试验设7个处理,以普良尼柯夫配方营养液进行试验来研究氮素对芥菜幼苗生长及酶活性的影响。水培试验结果表明,芥菜幼苗移栽后14 d,营养液中的总氮量为9 mmol.L-1(N3处理)的株高、叶数、最大叶长和最大叶宽均最大,分别为4.03 cm、3.00片.株-1、2.43 cm和1.08 cm,与N0处理的差异均达到极显著水平。芥菜苗移栽后42 d,以N3处理的株高、叶数、最大叶长、地上部、地下部、总生物量、根系活跃吸收面积和最长根长均最多,分别为4.30 cm、5.00片.株-1、3.36 cm、367.87 mg、27.13 mg、395.00 mg、53.03%和6.03 cm,它们与N0的差异均达到极显著水平,除最大叶长与N0处理的差异达到显著水平外。N3处理叶片的CAT和POD活性均较高,分别为16.89 U.mg-1.min-1和134.27 U.mg-1.min-1,MDA含量最小(2.29 nmol.g-1),与N0的差异均达到极显著水平。因此,在本试验条件上,营养液中的总氮量为9 mmol.L-1(N3)处理芥菜的幼苗生长和酶活性指标最好。建议营养液中施总氮量为9 mmol.L-1。     

Chemical composition and antimicrobial activity of the essential oil of Syzygium aromaticum flower bud (Clove) against fish systemic bacteria isolated from aquaculture sites

This paper describes the chemical composition and antimicrobial activity of the essential oil of Syzygium aromaticum against Vibrio spp. (n = 6), Edwardsiella spp. (n = 21), Aeromonas spp. (n = 2), Escherichia coli (n = 2), Flavobacterium spp. (n = 1), Salmonella spp. (n = 2), Streptococcus spp. (n = 1) and Pseudomonas spp. (n = 1) isolated from aquaculture sites as well as seven reference strains of bacteria, namely, Escherichia coli (ATCC 25922), Citrobacter freundii (ATCC 8090), Aeromonas hydrophila (ATCC 49140), Pseudomonas aeruginosa (ATCC 35032), Streptococcus agalactiae (ATCC13813), Edwardsiella tarda (ATCC 15947) and Yersinia enterocolitica (ATCC 23715). Nowadays, most antibiotics are no longer effective in controlling diseases in aquaculture, especially fish systemic bacterial diseases, due to increasing incidences of antibiotic resistance among pathogenic bacteria. Furthermore, many countries have banned antibiotics in aquaculture use due to public health concerns and environmental hazards. Therefore, this study was carried out to evaluate the potential of the essential oil of S. aromaticum as an alternate commercial antibiotic to antimicrobial agents against fish systemic bacteria in aquaculture. The essential oil of S. aromaticum was prepared using a steam distillation method, and the chemical composition was analysed using Gas chromatography-mass spectroscopy (GC-MS). Minimum inhibitory concentration (MIC) values of the essential oils against the tested bacteria were determined using the broth two fold micro dilution method, with kanamycin and eugenol as positive controls. The MIC values of the essential oil of S. aromaticum ranged from 0.015 μg·mL⁻¹ to 0.062 μg·mL⁻¹ against the tested bacterial isolates. A total of nine chemical compounds were detected in the essential oil, with eugenol (49.0%) and caryophyllene (7.5%) being the major compounds. The results of the present study indicate that the essential oil of S. aromaticum shows a huge potential to substitute commercial antibiotics as antimicrobial agents for aquaculture use.     

Development of a sandwich Dot-ELISA for detecting bovine viral diarrhea virus antigen with E2 recombinant protein

The IgG antibodies of rabbit anti-E2 protein of the bovine viral diarrhea virus were prepared by a general method from high efficiency serum immunized by E2 recombinant protein antigen expressed in E. coli prokaryotic expression system and were labeled to make enzyme-labeled antibody with the method of NaIO₄. A sandwich Dot enzyme-linked immunosorbent assay (Dot-ELISA) for the detection of BVDV was developed. The optimal reaction conditions of Dot-ELISA were determined. The results show that optimal coating antibody was 300 μg·mL⁻¹, the working concentration of HRP-labeled antibody was 1:50. The optimal blocking reagent and time were 5% bovine serum and 45 min. The minimum detection of the content of antigen reached 1.35 μg·mL⁻¹. Compared with the routine IDEXX ELISA test kit with the whole virus, its specificity, sensitivity and coincidence rate were 90.48%, 96.55% and 95.24%, respectively. Compared with the sandwich Dot-ELISA with the negative staining electron microscope and RT-PCR, the coincidence rates were 90.9% and 93.1%, respectively. In addition, Bovine viral diarrhea virus (BVDV) antigen of 178 samples collected from cow farms in the Hebei Province, China, were detected by the developed Dot-ELISA and the IDEXX BVDV antigen Test Kit simultaneously, BVDV antigen positive rate was 39.89%–41.01%. The result of detecting clinical samples demonstrated that the established method showed its specificity, sensitivity and repeatability, whereas the results were easily interpreted without an ELISA reader.     

西藏蜂胶抑菌活性及对金钗石斛茄病镰刀菌抑菌机理探究

为探究西藏蜂胶的抑菌活性及对金钗石斛茄病镰刀菌作用机理,以2种细菌3种真菌为供试菌,采用牛津杯法、菌饼法、最低抑菌浓度(MIC)和最低杀菌浓度(MBC)对西藏蜂胶的抑菌活性进行评价。通过研究西藏蜂胶处理后金钗石斛茄病镰刀菌菌丝形态、生长速率、细胞膜通透性及呼吸强度探究其抑菌机理。结果表明：(1)西藏蜂胶具有广谱抑菌性,其抑菌能力显著强于市售蜂胶。(2)以80%乙醇提取剂在pH为6的条件下提取的西藏蜂胶对5种供试菌抑菌效果最佳。(3)西藏蜂胶浓度为10 mg·mL^-1时对金钗石斛茄病镰刀菌抑制率达89%,抑菌中浓度(EC₅₀)为2.552mg·mL^-1;菌丝体细胞形态由饱满破裂到干瘪,细胞膜通透性增强,内容物泄漏;呼吸强度增大,能量代谢受阻,抑制菌丝体生长。综上所述,西藏蜂胶为天然广谱抑菌剂,利用其防治茄病镰刀菌所引起的植物性病害具有良好的开发前景及研究潜力。     

杠柳新甙A杀虫活性初探

测定了杠柳新甙A对鳞翅目昆虫粘虫、小菜蛾、菜青虫、小地老虎,同翅目昆虫麦二叉蚜和双翅目昆虫家蝇的胃毒和触杀活性。结果表明,杠柳新甙A对粘虫、小菜蛾、菜青虫、家蝇有强烈的胃毒活性,LC50分别为3.799 mg.mL-12、.090 mg.mL-1、4.189 mg.mL-1、1.546 mg.mL-1。对小菜蛾、家蝇、麦二叉蚜有触杀活性,LC50分别为4.495 mg.mL-13、.069 mg.mL-1、2.080 mg.mL-1。对小地老虎没有胃毒和触杀活性。     

Adventitious shoot regeneration from the leaves of some pear varieties (Pyrus spp.) grown in vitro

The pear (Pyrus spp.) is one of the most important temperate fruit crops. A complete protocol for adventitious shoot regeneration was developed from the leaves of four pear varieties grown in vitro: Abbe Fetel, Yali, Packham’s Triumph and Aikansui, and the Chinese rootstock variety Duli. Shoot explants were collected from the field and cultured in vitro in Murashige and Skoog (MS) media supplemented with 1.0 mg·L⁻¹ 6-benzylaminopurine (BA) and 0.1 mg·L⁻¹ indole-3-butyric acid (IBA). After four weeks, leaf explants of all 5 varieties grown in vitro were excised and cultured in MS media supplemented with 0.0 mg·L⁻¹, 0.2mg·L⁻¹, 0.5 mg·L⁻¹, 1.0 mg·L⁻¹ and 2.0 mg·L⁻¹ naphthaleneacetic acid (NAA) and 5.0 mg·L⁻¹ BA or with 1.0 mg·L⁻¹, 2.0 mg·L⁻¹ and 4.0 mg·L⁻¹ thidiazuron (TDZ). The cultures were maintained in darkness for 21 days for shoot induction in the shoot induction medium (IM), then transferred to the shoot expression medium (EM) in 1.0 mg·L⁻¹ TDZ without any auxins and kept in a growth room at (25±2)°C under a 16/8 h light/dark photoperiod regime for 8 weeks. Finally, the shoots were transferred to the MS shoot elongation medium (SEM) supplemented with 0.2 mg·L⁻¹ BA, 0.1 mg·L⁻¹ IBA and 0.2 mg·L⁻¹ gibberellic acid (GA₃). A combination of TDZ and NAA had a significant effect on the number of shoot regenerations in all 5 tested varieties. The maximum mean number of shoots and maximum number of shoots per leaf obtained from Yali variety were 11.8 (P⩽0.001) and 22, followed by Aikansui with 6.6 (P⩽0.001) and 4.6, and Duli with 8 (P⩽0.001) and 12, all arising from the combination of 0.2 mg·L⁻¹ NAA with 1.0 mg·L⁻¹ TDZ. For Packham’s Triumph and Abbe Fetel, the maximum mean number of shoots and maximum number of shoots per leaf were 5.6 (P⩽0.001), 4.8 and 8 (P⩽0.001), and 11, respectively, from the combination of NAA (1.0 mg·L⁻¹) and TDZ (2.0 mg·L⁻¹). Abbe Fetel was the only variety which produced significantly higher adventitious shoots from the two different combinations of 1.0 mg·L⁻¹ NAA and 5.0 mg·L⁻¹ BA (P⩽0.05), and 2.0 mg·L⁻¹ NAA and 5.0 mg·L⁻¹ BA (P⩽0.01). Some of the most prominent problems associated with shoot proliferation and regeneration were also observed and discussed in this paper.     

Effects of pentoxifylline, platelet activating factor and prostaglandin F 2-alpha on Giant Panda (Ailuropoda melanoleuca) post-thawed sperm in vitro fertilizing capability

Is it possible that Giant Panda (Ailuropoda melanoleuca) post-thawed sperm fertilization is improved with pentoxifylline (PF), platelet activated factor (PAF) and prostaglandin F 2-alpha (PGF_2α)? In our study Giant Panda post-thawed sperm was incubated in Ham’s F-10 medium with different concentration of PF, PAF and PGF_2α under 37°C. The effects of PF, PAF and PGF_2α on Giant Panda post-thawed sperm fertility were evaluated through sperm motility, survival time, sperm membrane integrity, acrosome state and heterospecific egg penetration. The results were that PF, PAF and PGF_2α all can affect Giant Panda post-thawed sperm in vitro fertilizing capability. In the experiment: 1 mg·mL^?1 PF was most suitable for improving Giant Panda post-thawed sperm in vitro fertilizing capability. In the 1 mg·mL^?1 PF group, sperm survival time was (15.33±4.73) h, the heterospecific egg penetration was 51.44% after incubating for 4 hours, the heterospecific egg penetration was 7.49% after incubating for 6 hours. The results of the 1 mg·mL^?1 PF group were significantly higher than those of the control group (P<0.01). The results were also higher than those of the other treatment groups; Treated Giant Panda post-thawed sperm with 50 ng·mL^?1 PAF had a better effect than 100 ng·mL^?1 PAF, but the sperm fertilizing capability was damaged when incubation time exceeded 2 hours; 50 ng·mL^?1 PGF_2α had no significant effect on Giant Panda postthawed sperm, but when the PGF_2α treated concentration was increased, sperm in vitro fertilizing capability decreased because of the damaged motility and declined acrosomal reaction rate. The conclusions suggest that it is possible to improve post-thawed Giant Panda sperm fertility with 1 mg·mL^?1 PF.     

不同提取方法对双叉犀金龟蛋白质提取率 及体外抗氧化活性的影响

双叉犀金龟（Allomyrina dichotoma）蛋白质含量丰富，是一种重要的资源昆虫。采用碱提法、酸提法、盐提法和醇提法分别提取双叉犀金龟幼虫蛋白质，并以DPPH自由基清除活性、ABTS自由基清除活性和总还原力为指标，测定4种方法所提取的蛋白质的抗氧化活性。结果显示：碱提法蛋白质提取率显著最高，蛋白质浓度与抗氧化活性之间呈现良好的正相关关系，但不同种类蛋白质的抗氧化能力有所不同；其中盐溶蛋白的DPPH自由基清除活性及总还原力最强，IC₅₀和A₇₀₀为1时的浓度分别0.360 4 和4.780 5 mg·mL^-1；酸溶蛋白的ABTS自由基清除活性最强，IC₅₀为4.439 0 mg·mL^-1。综合来看，提取方法不同时，双叉犀金龟蛋白质具有一定的ABTS自由基清除活性、较高的DPPH自由基清除活性和总还原力，可为后续进一步向食品、医药等方向开发利用提供理论参考。     

一株烟草肠杆菌（Enterobacter tabaci）S4菌株的鉴定及其效果测定

为筛选出一株具有微生物源植物调节剂功能的细菌,并探讨其潜在的生物功能,利用平板涂布法以及16S rRNA鉴定技术对菌株进行分离、鉴定;同时使用该菌株发酵液对番茄的种子和幼苗分别进行浸种和灌根处理,并进行农艺指标测定。结果表明：经鉴定该菌株为烟草肠杆菌,其发酵液对番茄种子的萌发、幼苗的生长具有显著的促进作用;发酵液浓度为1×10⁴ cfu·mL^-1时促生效果最好,与对照相比,根长、株高、干质量和鲜质量分别增加63.42%、46.17%、150.00%和144.83%。研究结果可为该菌株开发为微生物肥料或微生物源植物生长调节剂提供技术支持。     

微藻为营养源固定化硫酸盐还原菌对含铜废水动态去除试验研究

从底泥中筛选了一株脱硫弧菌属(Desulfovibrio)硫酸盐还原菌(SRB),选取易分解的普通小球藻、斜生栅藻、羊角月牙藻、螺旋鱼腥藻作为其营养源,以聚乙烯醇和海藻酸钠为主要包埋材料制备固定化SRB微球,并采用正交实验对包埋条件进行优化,然后通过上流式厌氧反应器考察了固定化SRB微球对含铜废水的长期处理效果。结果表明:微藻经过5 d发酵可分解为丙酸、丁酸、戊酸等脂肪酸,其中斜生栅藻由于发酵产物最佳被选为SRB营养源。制备微球最优配比为聚乙烯醇用量2%、海藻酸钠1%、氯化钙6%、二氧化硅1%、菌液50 m L,而且二氧化硅与聚乙烯醇用量对硫酸盐去除率影响最大。上流式厌氧反应器在反应初期对污染物的去除以微球的吸附作用为主,5 d后SRB菌发挥作用,在反应器运行0~36 d期间Cu2+的去除率可达到98%以上,运行45 d基本失效。每克微藻对Cu2+、SO2-4去除能力分别为45.28、182.17 mg·d~(-1)。