低蛋白质日粮补充赖氨酸、蛋氨酸对离乳期梅花鹿氮代谢的影响

为研究低蛋白质日粮添加赖氨酸和蛋氨酸对仔鹿氮代谢的影响,采用4×4完全拉丁方试验,选取3月龄、健康、离乳梅花鹿仔鹿4只,体重为(30±0.12)kg(X?±SD),进行消化代谢试验。对照组(Ⅰ组)饲喂16.28%粗蛋白质的高蛋白质日粮,试验组饲喂13.40%粗蛋白质,添加0.23%赖氨酸,并分别添加0(Ⅱ组)、0.06%(Ⅲ组)、0.12%(Ⅳ组)蛋氨酸的低蛋白质日粮。结果表明:1)对照组蛋白质消化率显著高于Ⅱ组(P<0.01)、Ⅲ组和Ⅳ组(P<0.05),脂肪消化率显著低于Ⅱ组(P<0.01),其他营养物质消化率差异不显著(P>0.05)。2)对照组和Ⅳ组蛋氨酸消化率显著高于Ⅱ组和Ⅲ组(P<0.05),对照组其余氨基酸消化率(赖氨酸、胱氨酸除外)显著高于各试验组(P<0.05)。3)对照组吸收氮显著高于Ⅱ组(P<0.01)、Ⅲ组和Ⅳ组(P<0.05),尿氮排放量显著高于各试验组(P<0.05),氮利用率及氮生物学效价低于各试验组(P>0.05)。4)对照组尿嘌呤衍生物总排放量显著大于Ⅱ组(P<0.01)和Ⅲ组(P<0.05),尿囊素显著大于Ⅱ组(P<0.01)、Ⅲ组和Ⅳ组(P<0.05),对照组、Ⅲ组和Ⅳ组黄嘌呤和次黄嘌呤显著高于Ⅱ组(P<0.01)。补充赖氨酸、蛋氨酸可改善低蛋白质日粮仔鹿营养物质消化率利用率,除粗蛋白外其他营养物质消化率与常规蛋白质水平相近,甚至更好,提高氮沉积、氮利用率和生物学效价,改善氮平衡,减少氮排放,降低环境污染。     

菲并吲哚里西啶生物碱及其盐衍生物 的生物活性研究

分别采用菌丝生长速率法和盆栽法,测定了一系列菲并吲哚里西啶生物碱及其盐衍生物的杀菌及除草活性。结果表明:该类生物碱及其盐衍生物表现出了很好的杀菌活性,尤其是生物碱安托芬 ± )-antofine]( 2 )和脱氧娃儿藤宁碱 ± )-deoxytylophorinine]( 3 )在50 μ g/mL下,对番茄早疫Alternaria solani、花生褐斑Cercospora arachidicola、苹果轮纹Physalospora piricola 和黄瓜枯萎Cladosporium cucumerium 4种菌体的抑制率达70%~100%;但未表现出明显的除草活性。     

山苍子油活性成分对木材真菌的抑制作用

为筛选出新的对绵腐卧孔菌、绿色木霉和彩绒革盖菌3种常见木材真菌有效的杀菌剂,采用菌丝生长速率法,测定了山苍子油主成分及其衍生物共10种化合物对这3种常见木材真菌的抑制率,建立毒力方程并分析其活性。结果表明:10种化合物对3种常见木材真菌的生长均表现出一定的抑制作用,而且随着浓度的升高,抑制作用增强;通过10种化合物对3种常见木材真菌的毒力回归分析,并与三唑酮相比较,依次筛选出对绵腐卧孔菌、绿色木霉和彩绒革盖菌的抑制作用最强的分别为柠檬醛1,2-丙二醇缩醛、β-紫罗兰酮和鸢尾酮,其半数有效抑制质量浓度(EC50)依次分别为18.69、23.50和32.21 mg/L。3种真菌分别经柠檬醛1,2-丙二醇缩醛、β-紫罗兰酮和鸢尾酮处理后,菌体细胞膜的相对渗透率发生变化,表明山苍子油活性成分的木材防腐作用与菌体细胞膜遭破坏有关。     

银杏叶聚戊烯醇含氮和含卤素衍生物的抑菌活性研究

利用含氮和含卤素试剂对银杏叶聚戊烯醇末端羟基进行含氮和含卤素的衍生化改性,结果得到5种衍生物,分别为聚戊烯基邻苯二甲酰亚胺(GPH)、氨基聚戊烯醇(GAM)、聚戊烯基季铵盐(GAS)、聚戊烯基三氟乙酰(GTF)和聚戊烯基氯乙酰(GCH),并用~1H NMR分别表征并证实了产物结构。通过比较产物抑菌圈直径和最小抑质量浓度(MIC)来筛选出抗菌作用较强的衍生物,结果显示:GAS对于大肠杆菌和金黄色葡萄球菌的抗菌活性均为最高,其抑菌圈为19.1~19.8 mm,MIC均为31.3 mg/L。同时研究了GAS在亚抑菌质量浓度下(15.6 mg/L)对大肠杆菌和金黄色葡萄球菌的杀菌曲线,结果显示:GAS对大肠杆菌和金黄色葡萄球菌在48 h内具有一定抗菌性;在前8 h内,GAS对于大肠杆菌和金黄色葡萄球菌的杀菌作用较强,致使菌群数量迅速下降;8 h以后,两种菌群都有不同程度的再生,抑菌活性减弱。     

三肽纤维素酯的制备及应用研究

以微晶纤维素为原料,芴甲氧羰基-L-脯氨酸(FMOC-L-Pro-OH)、芴甲氧羰基-L-缬氨酰-L-苯丙氨酸(FMOC-L-Val-L-Phe-OH)和3,5-二硝基苯甲酸为衍生化试剂,经酰氯化、酯化、肽链的延长和氨基的修饰等反应,合成了末端氨基被修饰的三肽纤维素酯(TPC)。通过实验证实三肽若要与纤维素成酯,必须采用先酯化后肽链延长的方式,其中关键步骤为酯化反应,其反应条件为:纤维素在LiCl/DMAc溶液中的质量浓度为20 g/L,温度100℃,n(酰氯)∶n(纤维素中羟基总量)为3∶1,反应时间20 h。再通过肽链延长、氨基修饰反应,最终可得到取代度为2.15的三肽纤维素酯。经过FT-IR、TG、XRD和元素分析等多种分析手段测试可知,3,5-二硝基苯甲酸对肽链末端进行了成功的修饰,该反应路径可行。酯化反应的产物根据沉淀析出液不同,内部氢键产生也不相同,可得到功能不同的三肽纤维素酯。TPC的应用实验结果表明,以甲醇为沉淀析出液的纤维素酯,是良好的肠溶包衣材料,具有遮光性强崩解迅速的特点,但其生理毒性有待进一步研究;以水为沉淀析出液的纤维素酯,被制成手性涂敷柱后,综合了刷型固定相与纤维素固定相的两大优势,拆分能力强大高效,耐化学性极佳,适用范围比以往涂敷柱更广泛,尤其适用于四氢呋喃流动相体系。     

Preparation and sizing mechanisms of neutral rosin size II: functions of rosin derivatives on sizing efficiency

Four rosin derivatives, including rosin esters and rosinamides, were synthesized and used to prepare neutral rosin sizes. Their effects during sizing are discussed in detail. Compared to natural rosin, the rosin derivatives had nearly no effect on sizing even at high retention levels in paper. However, the rosin derivatives in the rosin sizes improved the stability of the emulsion size particles, and there was good correlation between the sizing effect and the stability of the emulsion sizes under neutral to alkaline conditions. On the other hand, the structure of the rosin derivatives significantly influenced the stability and sizing effect of the neutral rosin sizes. In particular, for glycerin rosin ester-rosin sizes, the emulsion stability and sizing effect increased with an increasing proportion of dirosinate, among the glycerin rosin esters. Consequently, it was suggested that the rosin derivatives hardly contribute to the sizing performance of paper but predominantly function to stabilize the neutral rosin size particles, thereby improving the efficiency of the size under neutral to alkaline sizing conditions. Also it was supposed that glycerol dirosinate in the neutral rosin size would probably enable formation of a more stable particle structure to prevent the destructive action of the OH^– ion.This research was presented in part at the 48th annual meeting of the Japan Wood Research Society, Shizuoka, April 1998     

Synthesis and anti-mildew activity of 5-(2-aroyl)aryloxymethyl-2-phenyl-1 ,3,4-oxadiazoles against downy mildew of pearl millet

A manipulatively simple, rapid, high-yielding and environmentally benign method for the integration of a heterocyclic ring, 1,3,4-oxadiazole, at the benzophenone nucleus has been achieved through intramolecular cyclization of substituted aroylaryloxyacetohydrazides to substituted 5-(2-aroyl)aryloxymethyl-2-phenyl-1,3,4-oxadiazoles under solventless 'dry' conditions using montmorillonite K10 clay and microwave irradiation. A comparison is made of the microwave-accelerated reaction with conventional heating conditions. Certain of the derivatives tested showed significant anti-mildew activity against Sclerospora graminicola (Sacc) Schroeter, the downy mildew pathogen of pearl millet.     

Genetic diversity in advanced derivatives of Brassica interspecific hybrids

Genetic diversity among the 88 entries including eighty F₄ derivatives i.e., 20 each selected from Brassica crosses viz., B. juncea × B. napus, B. juncea × B. rapa var. toria, B. juncea ×B. rapa var. yellowsarson and B. tournefortii × B. juncea, and eight parent genotypes was assessed through multivariate analysis (D² statistic). Significant differences among the family groupsas well as within the family were recorded for all the 14 characters studied. The D² analysis revealed enormous diversity among the interspecific cross derivatives. The genetic distances calculated among different Brassica species revealed that B. tournefortii had maximumdiversity with B. juncea followed by B. napus, B.rapa var. toria and B. rapa var. yellow sarson.Amongst interspecific crosses, maximum diversity was noticed indescendants of cross B. tournefortii × B. juncea followed byB. juncea × B. napus, B. juncea × B.rapa var. toria and the least in the cross B. juncea ×B. rapa var. yellow sarson. These results indicated that the derivatives selected from cross of diverse parents revealed greater diversity. The clustering pattern showed that many derivatives of the cross fell into the same cluster but in many cases in spite of common ancestry many descendants of the cross spread over different clusters. The characters, namely, plant height, secondary branches per plant, days to flowering and1000-seed weight were contributed maximum towards genetic divergence. This revised version was published online in August 2006 with corrections to the Cover Date.     

新手性吡啶类配体的合成及其不对称诱导性能研究

以2,6-二甲基吡啶和2,6-二溴吡啶为原料,经锂试剂分别与光学活性的樟脑、薄荷酮和3-甲酰基蒎烷反应合成了4个新的手性吡啶类化合物。测定了它们在苯甲醛和二乙基锌加成反应中的不对称诱导性能。     

The use of purine derivatives/creatinine ratio in spot urine samples as an index of microbial protein supply in Yerli Kara crossbred cattle

Three experiments were conducted to evaluate the use of purine derivatives (PD)/creatinine ratio in spot urine samples as an index of microbial protein supply in Yerli Kara crossbred cattle (YK-C). In Experiment I, response of daily PD excretion to feed intake in YK-C at state farm was measured. In Experiment II, spot urine sampling techniques was applied at state farm and four YK-C bulls were used. In Experiment III, spot urine sampling technique was applied at small-holder farms. There were significant correlations (R² = 0.99) between PD excretion (mmol/day) and digestible organic matter intake (DOMI) (kg/day) in Experiment I, Y = 12.5 (± 0.5) + 19.7 (± 3.5)X (R² = 0.99, n = 16). The equation obtained from Experiment I could be expressed as: Y = − 2.3 (± 0.3) + 0.953 (± 0.06)X, (R² = 0.99, n = 49) where Y is PD excretion (mmol/day) and X is the PDC index. The PDC index was calculated as the molar concentration ratio of PD to creatinine times the metabolic body weight (kg). The corresponding microbial-N values to PDC index of groups I, II and III in developed banding system are 15–25 g/day. Experimentally estimated DOMI was 2.21 ± 0.15 kg/day. Estimated DOMI of groups I, II, and III were 2.8 ± 0.6, 2.6 ± 0.7 and 2.7 ± 0.7 kg/day, respectively. In conclusion, the PDC index in spot urine samples could be used under similar farm condition as an indicator of microbial protein supply in YK-C cattle. Estimated DOMI from PDC index in spot urine samples under defined field conditions may help the development of feeding strategies for YK-C cattle held by small holders.