响应面法优化黑桑椹黄酮超声波提取工艺

为优化黑桑椹总黄酮超声波提取工艺,以库尔勒市阿瓦提乡采摘园种植的黑桑椹果实为原料,在单因素试验结果的基础上,分别选取乙醇体积分数、提取温度、提取时间、液料比4 个因素开展Box-Behnken 中心组合试验,利用Design-Expert 8.06 软件对结果进行分析和优化。结果表明,黑桑椹中黄酮类物质的最佳提取工艺条件为：乙醇体积分数60%,提取温度70 ℃,超声时间40 min,液料比30∶1（mL/g）。在此工艺条件下,黑桑椹黄酮类物质提取量为9.565 mg/g。说明应用响应面法所得到的提取工艺参数可行性强、可靠性高。     

烤烟总氮含量和氮碱比与物理性状的关系分析

试验以我国主产烟区的主栽烤烟品种K326为材料,测定X2F(下橘二)等级共计124份样品的总氮、烟碱含量和物理性状,系统地分析总氮含量、氮碱比与物理性状的相互关系。结果表明,总氮含量、氮碱比和物理性状在样品间存在着广泛的变异。总氮含量随单叶重、叶长、叶面密度的增加而逐步下降;氮碱比随叶长、叶宽的增加而上升,随叶面密度的增加而逐渐下降。总氮与叶长、叶面密度的关系可分别用逆函数■=0.827 38.047/x、复合函数■=1.880×0.996x描述;氮碱比与叶宽、叶面密度的关系可分别用复合函数■=0.413×1.023x描述、幂函数描述■=2.791x-0.354。     

Effect of foliar boron application on boron,chlorophyll, phenol,sugars and hormones concentration of olive (Olea europaea L.) buds,leaves, and fruits

The objective of this study is to investigate the effect of different time and rates of boron (B) foliar application on olive (Olea europaea L.) tree's tissue boron concentration, total phenol, chlorophyll, total soluble sugars, and endogenous hormones. A field experiment was conducted during two successive seasons 2010/2011 and 2011/2012 using 20 years old olive trees cv. Frantoio. The trees are grown in sandy soil planted at 5 × 5 m apart under drip irrigation system at the Nuclear Research Center Experimental Farm, Inshas, El-Qaliubiya Governorate, Egypt. Boron was applied foliarly as boric acid at the following rates (0.0, 100, 200, 300, 400, 500 mg L^?1) at flower initiation and after 1 and 2 months from flower initiation. Results showed that boron was significantly effective in increasing leaf, bud, and fruit boron concentration. Total phenol concentration in leaves and buds were significantly highest in the control treatment, significantly decreased as the boron application rate increased. Total chlorophyll, chlorophyll a and b, and total soluble sugars significantly increased as the boron application rate increased and the highest increase was achieved at 200 mg L^?1 boron concentration rate. Leaf and bud endogenous indole acetic acid (IAA) and abscisic acid (ABA) were highest in the control treatment; they decreased as the boron application rate increased. However, gibberellic acid (GA₃) increased in response to boron treatments compared with the control. The maximum increase was observed at 200 mg L^?1 boron rate. We concluded that boron is mobile in olive tree as reproductive organs accumulated more boron than vegetative organs. There is evidence that boron is involved in reduction of phenols, increase in fruit set, and in sugar transport. A balance in endogenous hormones (IAA, GA, ABA) concentrations in olive tree has induced the maximum fruit set and yield.     

磷、钾对番茄可溶性碳水化合物分配的影响

以番茄苗为试验材料,研究了不同浓度磷、钾对番茄植株可溶性碳水化舍物分配的影响。结果表明：磷、钾亏缺处理45d后,与正常磷、钾处理相比,磷亏缺的植株冠根比下降,而钾亏缺的植株冠根比则上升。钾亏缺的植株叶片中,蔗糖、还原糖和总可溶性糖含量均表现为上升,根中则表现为下降。磷亏缺的植株叶片中,蔗糖、还原糖和总可溶性糖含量基本不变,而在根中则表现为不同程度的增加。在叶和根的总可溶性糖中,钾亏缺和磷亏缺的植株,根部总可溶性糖所占的比例分别为10．71％和45．65％,两者的对照分别为28．63％和33．11％。上述结果表明,钾和磷在光合产物的转运中所起的作用不同,植株中营养元素亏缺不同,干物质在不同部位的分配也不同。     

沙冬青种子总生物碱对小鼠急性毒性试验研究

用酸水法提取沙冬青种子总生物碱,采用小鼠口腔灌服的方法对该生物碱进行了急性毒性试验,利用改良寇氏法测定该生物碱的LD50.结果表明:沙冬青种子总生物碱对小鼠口服的LD50为588.71mg/kg,LD50的95%可信限为513.93～674.37mg/kg.剖检变化为心脏色泽暗淡,肝脏和肾脏肿大,其它脏器无眼观病变.组织学变化呈现心肌纤维肿胀,肌浆内出现大量红色细小颗粒,间质血管充血;肝细胞肿大,胞浆内出现大小不等、多少不一的空泡,部分肝细胞坏死崩解;脾小体萎缩,淋巴细胞减少;肺脏血管充血;肾小管上皮细胞肿胀变性,部分肾小管上皮细胞坏死崩解.沙冬青种子总生物碱为低毒化合物,小鼠在沙冬青种子总生物碱中毒后,心脏、肝脏、脾脏和肾脏等主要器官都受到一定程度的损害,但对小鼠的持续影响较小.     

HEMOPOIETIC RESPONSES OF THE CAT TO TOTAL BODY IRRADIATION FOLLOWED BY CHEMOTHERAPY

Cats with lymphosarcoma are affected with rapidly progressive, fatal neoplasia of hemopoietic tissues. The very aggressive nature of this type of neoplasia requires intense therapy, which in most instances is only palliative. A combination of total body irradiation and cytotoxic chemotherapy in four normal cats was followed by similar patterns of leukopenia and throm-bocytopenia in all cats. The radiation protocol and the complications of the transient throm-bocytopenia and leukopenia are discussed and compared with reports of similar efforts in human medicine. The responses from these normal cats were quite similar to those seen in humans undergoing similar therapy. The cat may be considered as a possible model for further radiotherapy research.     

Effects of suspended solids in the survival and haematological parameters of pacu juveniles (Piaractus mesopotamicus) in a biofloc technology culture system

This study determined the effects of total suspended solids (TSS) on pacu (Piaractus mesopotamicus) culture in a biofloc technology (BFT) system by performing two experiments. Experiment 1 evaluated the LC50-96 h of pacu at seven TSS levels (0, 1500, 3000, 4000, 5000, 6000 and 7000 mg L^?1). Experiment 2 evaluated haematological variables (glucose, pH, haematocrit, haemoglobin, erythrocytes and haematimetric indices) in juveniles exposed to five different sublethal TSS concentrations (0, 250, 500, 750 and 1000 mg L^?1) for 5 days. Treatments below 5000 mg L^?1 did not cause mortality, and the LC50-96 h of TSS was estimated at 5477 mg L^?1. The TSS concentrations that caused mortality in pacu juveniles were extremely high and rarely maintained in culture systems. Exposure to high TSS concentrations (mainly 750 and 1000 mg L^?1) increased blood glucose, pH, heamatocrit, erythrocytes, haemoglobin values and haematimetric indices on the first day. On the fifth day, most of the evaluated parameters stabilized at different TSS concentrations. In conclusion, pacu exposed to high TSS concentrations for short periods may undergo physiological changes, and TSS concentrations below 250 mg L^?1 are recommended for its culture in a BFT system.     

四大药用菊花功能成分的比较研究

为了比较4种药用菊花的品质特征,采用比色法测定总黄酮含量,HPLC测定绿原酸含量,GC-MS分析挥发油的成分.结果表明,贡菊、滁菊、亳菊和杭菊中总黄酮的含量分别为5.608%、4.619%、4.372%和3.017%;绿原酸含量分别为0.345%、0.207%、0.337%和0.131%;挥发油总量分别为0.243%、0.524%、0.388%和0.212%;GC-MS分离鉴定出的化合物中贡菊有18种,滁菊有46种,亳菊有35种,杭菊有6种.可见贡菊的主要功能成分较其他3种菊花含量高,并且具有较好的香气品质,认为贡菊可能不仅更适合药用,同时适于作为饮料、功能和保健食品的原料.     

烤烟油菜轮作及平衡施肥对土壤有机碳含量的影响

为探究烤烟油菜轮作及平衡施肥对土壤有机碳(SOC)含量的影响,通过田间小区试验,采用双因素裂区设计,测定烤烟与3个油菜品种（‘重蓉油1号’、‘德油早1号’和‘GSX-1’）轮作以及平衡施肥（减氮和增磷）下油菜季与烤烟季土壤的总有机碳(TOC)和可溶性有机碳(DOC)含量。结果表明,从油菜移栽初期到收获,SOC含量均有不同程度的上升,上升幅度为7.7%～166.49%;轮作处理的TOC含量和DOC含量相较对照有所增加,且收获期（180天）的TOC含量和DOC含量以‘重蓉油1号’最高,分别为对照处理的1.26和4.78倍。在烤烟整个生育期内,除个别处理外,其他土壤DOC含量呈下降趋势,TOC含量有所增加。此外,就施肥模式而言,减氮处理效果最佳。在烤烟收获期,除‘德油早1号’外,土壤TOC含量均以减氮处理最高,分别为常规施肥处理的1.20、1.44和1.02倍。综上‘,重蓉油1号’油菜与烤烟轮作、减施氮肥时SOC含量较高,是当地较优的种植模式。     

航天紫花苜蓿中黄酮的提取及抑菌活性

用索氏回流法正交提取航天紫花苜蓿(Medicago sativa)中的黄酮(芦丁),以510 nm最大吸光度进行可见光谱检测,测定芦丁含量,并对两种供试菌进行体外抑菌活性测定。结果表明,通过单因素试验确定的各因素影响能力大小为超声提取时间料液比乙醇浓度,芦丁含量最高为10.04 mg·g-1;大肠埃希氏杆菌的最小抗菌浓度为0.40 mg·g-1,金黄色葡萄球菌的最小抗菌浓度为0.70 mg·g-1。