不同地域环境对枸杞蛋白质和药用氨基酸含量的影响

根据2000～2001年我国北方六省(区)多点枸杞采样资料和田间试验资料,利用K-均值聚类方法和非线性回归方法,对比分析了宁杞1号枸杞蛋白质和9种药用氨基酸含量的差异和特点,以及生态因子对它们的影响。分析结果表明,不同地域栽种的宁杞1号枸杞蛋白质和9种药用氨基酸含量的变异系数分别为16.58%和16.22%,除品种因子的决定作用以外,环境条件对枸杞蛋白质含量有一定作用,其中土壤水解氮含量对蛋白质和氨基酸合成有一定作用,二者呈对数关系。     

Effects of 11, 12-EET and ischemic preconditioning on phosphorylated ERK and p38 MAPK during ischemia and reperfusion in rat myocardium

AIM: In order to study the relationship between the ERK and p38 MAPK activation and the protection of 11, 12-epoxyeicosatrienoic acid (11, 12-EET) and ischemia preconditioning (IP), the effects of 11, 12-EET and ischemic preconditioning on phosphorylated ERK and p38 MAPK during ischemia and reperfusion in rat myocardium were examined. METHODS: The rat heart was subjected to ischemia for 5 min by ligating the left anterior descending coronary artery followed by reperfusion for 5 min (two times) to undergo ischemia preconditioning. The rats were divided into 5 groups: (1) control; (2) sham group; (3) ischemia/reperfusion (I/R) group, in which the rat heart suffered from 60 min ischemia followed by 30 min reperfusion; (4) IP plus I/R group; (5) EET plus I/R group, in which 6.28×10^-8 mol/L 11, 12-EET was injected intravenously 20 min before I/R. The heart function was examined, and phosphorylated ERK and p38 MAPK were detected by Western blot. RESULTS: At 30 min reperfusion, +dp/dt_max, -dp/dt_max and LVDP decreased significantly in I/R group compared with sham group, IP plus I/R group and EET plus I/R group; Phosphorylated ERK1/2 level was higher in I/R group than sham group, but was lower in I/R group than IP plus I/R group and EET plus I/R group; Phosphorylated p38 MAPK level was lower in control, sham, IP plus I/R and EET plus I/R group than I/R group. CONCLUSION: 11,12-EET protects rat heart against ischemia/reperfusion injury, the mechanism may be related to activation of ERK1/2 and inhibition of p38 MAPK.     

Ascorbic acid level of Belgian apple genetic resources

With the help of the public, a wide collection of old apple cultivars (cvs) was established progressively at our Department from 1975 onwards. Currently, more than 1400 apple accessions are being maintained and three quarters of them are subjected to field evaluation for disease resistance and agronomic characters. This paper presents results of the ascorbic acid (Vitamin C) contents of old cvs combining interesting disease resistance and agronomic features in order to promote them as cvs adapted to production systems which are more environmentally friendly or to be used as parents in breeding programmes. First, a methodological study shows the importance of the variability of ascorbic acid content depending on fruit position in the trees, fruit size, fruit skin colour and maturity stage. Statistical analyses show that the sample size of six fruits per cv is sufficient to detect a difference of 20% between cvs. Old apple cvs such as Grenadier^RGF, Transparente de Croncels, Bramley’s Seedling, Reinette des Capucins, Reinette Libotte and Reinette de Waleffe contain three and seven times more ascorbic acid than the commercial cvs Gala and Elstar, respectively. The paper highlights the need to evaluate the rich potential in our genetic resources.     

抗生素工业化生产中一级种子罐染菌原因及解决方法

抗生素工业化生产中,菌种往往需要扩大繁殖到一定的数量后再进入发酵罐.在一级种子制备过程中,引起染菌的因素很多,极大地影响了抗生素生产的产量和质量.解决一级种子罐染菌的方法,除制定科学的岗位SOP并不断提高操作者的技能外,更重要的是要加强工艺管理,树立以预防为主的思想,根据微生物特性,强化环境清洁,加强设备清洁、维修,操作时实行定人、定操作.     

Contribution of insulin to the ascorbate recycling system in the chicken liver

The effect of insulin on the ascorbate recycling system in the chicken liver was examined. First, insulin was injected subcutaneously into the chicken, and liver glutathione‐dependent dehydroascorbate reductase (GSH‐DHAR) activity was determined. Insulin increased liver GSH‐DHAR activity, but did not affect plasma and liver ascorbate concentration. Dehydroascorbate increased plasma and liver ascorbate levels, and liver GSH‐DHAR activity. However, distinct changes in plasma insulin level were not observed by dehydroascorbate injection. In addition, reduction of external dehydroascorbate in cultured chicken hepatocytes could not be observed in an insulin‐deprived culture, although the cells reduced external dehydroascorbate in a serum‐free culture with insulin. We concluded that insulin affects the ascorbate recycling system as an essential factor in the chicken liver.     

体外试验中不同粗精比对山羊瘤胃细菌氨态氮利用效率的影响

利用体外发酵法研究了4种粗精比(10∶0、8∶2、6∶4和4∶6)底物对山羊瘤胃细菌产量、15NH3-N利用效率的影响。结果表明:混合培养液的pH值与氨态氮浓度在8h内急剧下降,而后至24h呈缓慢下降;经24h培养的细菌产量在8∶2、6∶4和4∶6组中差异不显著(P>0.05),但都极显著地高于10∶0组(P<0.01);细菌体15N丰度以8∶2及4∶6组较高,显著高于10∶0和6∶4组(P<0.05);细菌体15N富集量以8∶2组最高,底物547.43μg15N中有120.44μg被细菌体富集,显著高于10∶0组(P<0.05),但6∶4、4∶6组与10∶0组间差异均不显著(P>0.05)。细菌赖氨酸的相对百分组成随精饲料比例的增加而显著增加,胱氨酸在粗饲料组(10∶0)显著高于其它组,但各精饲料添加组间差异不显著,组氨酸以8∶2组为最高,显著高于10∶0组,但与其它精饲料添加组间差异不显著(P>0.05)。     

Expression of the tobacco β-1,3-glucanase gene, PR-2d, following induction of SAR with Peronospora tabacina

Systemic acquired resistance (SAR) is induced following inoculation of Peronospora tabacina sporangia into the stems of Nicotiana tabacum plants highly susceptible to the pathogen. Previous results have shown that accumulation of acidic β-1,3-glucanases (PR-2's) following induction of SAR by P. tabacina may contribute to resistance to P. tabacina. We showed that up-regulation of the PR-2 gene, PR-2d, following stem inoculation with P. tabacina, is associated with SAR. Studies using plants transformed with GUS constructs containing the full length promoter from PR-2d or promoter deletions, provided evidence that a previously characterized regulatory element that is involved in response to salicylic acid (SA), may be involved in regulation of PR-2d following induction of SAR with P. tabacina. This work provides evidence that regulation of PR-2 genes during P. tabacina-induced SAR may be similar to regulation of these genes during infection of N-gene tobacco by TMV or following exogenous application of SA, and provides further support for the role of SA in regulation of genes during P. tabacina-induced SAR.     

HBV/HAV复合抗原基因在CHO细胞中的表达

为探讨HBV／HAV复合疫苗的可行性，利用DNA重组技术将HBsAg与HAW复合多表位抗原基因VPX进行融合，插入到真核表达质粒pVAX1多克隆位点，构建成核酸表达疫苗pVAX1／SVPX，将其转染CHO细胞。转染细胞培养48h后，进行RTPCR、Western-blot、ELISA分析，结果表明HBV／HAV复合抗原基因SVPX能够在CHO细胞内转录、表达，融合蛋白具有HBV和HAV抗原的特性。     

添加不同酵母培养物对瘤胃纤维分解菌群和纤维素酶活的影响

用3种酵母培养物(YC- 1、YC 2和YC- 3)分别饲喂4头带有永久性瘤胃瘘管的肉牛,研究培养物对瘤胃发酵、纤维分解酶活性和3种纤维分解菌数量的影响,结果表明:YC 2处理的乙酸、丙酸、丁酸和总 VFA浓度显著高于对照组(P<0 .05),YC 1和YC 3处理的乙酸/丙酸比例显著降低(P<0 .01);各处理均能显著提高瘤胃内羧甲基纤维素酶、水杨苷酶和木聚糖酶的活性(P<0 .01);各处理都显著提高黄化瘤胃球菌的相对比例(P<0 .01),16SrRNA特异性寡聚核苷酸探针杂交法分析测定结果表明 3 种纤维分解菌在瘤胃细菌中所占比例为 3. 80%±0 .2%。     

0～3周龄北京鸭氨基酸理想模式的研究

依据扣除法原理，根据现有氨基酸需要量标准和目前的研究结果规划出一种氨基酸模式，依次将模式中赖氨酸、蛋氨酸、色氨酸、苏氨酸、异亮氨酸扣除20％，而非扣除的氨基酸量保持不变，来确定扣除某一种氨基酸后对育雏期北京鸭生产性能和血液生化指标的影响，确定出理想的氨基酸比例。试验共设6个处理组，为6种氨基酸模式，每个处理设4个重复。结果表明：北京鸭育雏期氨基酸理想模式为赖氨酸：蛋氨酸：色氨酸：苏氨酸：异亮氨酸=100：42：22：38：48。