饲粮中添加杜仲叶对断奶仔猪生长性能、抗氧化力和免疫功能的影响

在断奶仔猪饲粮中添加不同形式的杜仲叶,研究其对仔猪生长性能、腹泻率、抗氧化力及免疫功能的影响,以评估它们在养殖初期替代抗生素的能力。将断奶仔猪(杜×长×大)随机分成对照组、抗生素组(75 mg/kg金霉素)和三个杜仲叶组(杜仲叶提取物、发酵杜仲叶、杜仲叶干粉),每组10头,进行28天养殖试验。结果表明:与对照相比,杜仲叶提取物组仔猪平均日增重(ADG)显著提高并降低料重比(F/G)(P<0.05);与抗生素组相比,杜仲叶提取物组和杜仲叶发酵组ADG和F/G均无显著差异(P>0.05);各组之间平均日采食量(ADFI)差异不显著(P>0.05)。与对照组相比,抗生素组和杜仲叶提取物组仔猪腹泻率显著降低(P<0.05)。与对照组相比,抗生素组和三种杜仲叶组均降低仔猪血液丙二醛含量和提高总抗氧化力(P<0.01),而抗生素组、杜仲叶提取物组和杜仲叶发酵组还显著提高血液免疫球蛋白IgM含量(P<0.01),且表现出提高血液IgG含量的趋势(P=0.06)。与其他各组相比,杜仲叶提取物组可显著提高肝脏指数(P<0.05);肝脏重量、脾脏重量和脾脏指数在各组之间无显著差异(P>0.05)。饲粮中添加杜仲叶提取物可改善断奶仔猪的生长性能,降低腹泻率,提高仔猪抗氧化力和免疫功能,其效果优于发酵杜仲叶和杜仲叶干粉,并具备一定的抗生素替代潜力。     

三种绿原酸提取物的抑菌和抗氧化效果比较

本文研究平卧菊三七、金银花、杜仲叶绿原酸提取物的抑菌和抗氧化作用,为选择合适的天然食品防腐剂和抗氧化剂提供参考。采用纸片扩散法,探讨平卧菊三七、金银花、杜仲叶绿原酸提取物分别对几种常见致病菌的抑菌活性。在抗氧化作用方面,探讨平卧菊三七、金银花、杜仲叶绿原酸提取物分别在抗脂质过氧化能力、还原能力和清除DPPH·方面进行了研究。结果表明,三种植物绿原酸提取物对细菌均有很强的抑制作用,特别是对金黄色葡萄球菌的抑制作用,在浓度为100 mg/m L时,平卧菊三七绿原酸提取物、金银花绿原酸提取物、杜仲叶绿原酸提取物的抑菌圈分别可达21.4、23.6、24.7 mm。同时,对大肠杆菌和沙门氏菌液也有明显的抑制作用,但是对酵母菌的抑菌作用不明显;且各供试物的抑菌强弱顺序为:杜仲叶绿原酸提取物金银花绿原酸提取物平卧菊三七绿原酸提取物。三种植物中绿原酸提取物中,杜仲叶绿原酸提取物的抗脂质过氧化能力、还原能力和清除DPPH·能力均高于其他两种绿原酸提取物。本文揭示了在平卧菊三七、金银花、杜仲叶这三种绿原酸提取物中,杜仲叶绿原酸提取物有较强的抑菌活性和抗氧化作用。     

不同地理种源杜仲叶片中绿原酸和总黄酮的含量

杜仲（ＥｕｃｏｍｍｉａｕｌｍｏｉｄｅｓＯｌｉｖ．）是我国所特有的经济植物。传统以树皮入药,近年来研究表明,杜仲叶与皮的化学成分基本相同,药效类似［１～４］。杜仲叶、皮中主含环烯醚萜甙类、黄酮类及酚酸类成分。研究不同地理种源和不同季节杜仲叶片绿原酸和总...     

杜仲叶中多糖分子物的提取及其对运动人体免疫机能的影响

本研究通过水热法和微波辅助法提取杜仲叶和杜仲皮中的多糖。采用化学分析和红外分析对4种提取物B-HWE、B-MAE、L-HWE和L-MAE的活性成分和结构特点进行表征,研究杜仲皮和杜仲叶中多糖分子物的抗氧化活性及对运动人体免疫机能的影响。研究结果表明:4种提取物有中多糖的结构特性没有明显的差异。微波辅助提取,使天然抗氧化剂和多糖的产量提高。EUOP1、EUOP2、EUSP1和EUSP2的产率分别占9.26%、10.51%、5.99%和7.38%。杜仲皮和叶内生物活性物含量差异很大,葡萄糖占主要糖成分的53.9%～63.2%和少量半乳糖占10.6%～16.1%。叶中多糖EUOP1和EUOP2的产量显著高于从杜仲皮获得的EUSP1和EUSP2。杜仲提取物对DPPH自由基的抑制活性遵循有序杜仲叶杜仲皮,微波辅助提取明显改变了提取物中多糖的剂量,提高了抗氧化活性。杜仲提取物抗氧化活性的排序依次为L-MAEL-HWEB-MAEB-HWE。杜仲提取物还可显著提高血清中IL-2、IL-4、lgG、lgM水平,其免疫活性排序与抗氧化活性相同。与对组照组相比,EUOP2组中IL-2、IL-4、lgG、lgM分别提高了20.17%、43.07%、28.73%、15.0%。杜仲多糖主要通过提高机体免疫应答能力,从而提高运动人体免疫机能。说明杜仲多糖具有提高人体免疫机能的功效。     

杜仲叶黄酮苷元水解及富集纯化工艺研究

以杜仲叶提取物为原料,采用酸水解的方法制备杜仲叶黄酮苷元,通过单因素及正交试验优化杜仲叶黄酮苷元的水解条件;并研究了聚酰胺两步法富集黄酮苷元的工艺条件。结果表明:当料液比为2∶1(mg/m L)时,杜仲叶黄酮苷元水解的最佳工艺参数为:水解温度80℃,水解时间3 h,盐酸浓度6 mol/L,黄酮苷元的含量可达到2.512%。水解样品经过一次聚酰胺静态吸附,黄酮苷元的纯度可达12.87%,再经聚酰胺二次富集,杜仲黄酮苷元纯度可达63.19%。     

不同季节施用KClO3化学调控剂对龙眼促花与果实品质的影响*

在茂名市水果科学研究所实验基地试验研究了不同季节施用以KClO₃为主要成份的龙眼促花调控剂对龙眼促花和果实质量影响的效应。结果表明:按龙眼树冠直径每米施药量180g处理,不同季节施药的促花效果存在显著差别,干旱少雨季节促花效果较佳,湿润多雨季节促花效果较差,促花效果与气候条件、龙眼树体长势及枝梢老熟程度有密切关系;不同季节成熟收获的龙眼果实质量存在一定差异,反季节与正造栽培收获的龙眼相比,可食率提高,果核变小,但糖份含量等品质指标则较差,其中以春末夏初收获的果实个大肉厚,外观较佳,市场销售价较高,因此夏末至秋初干燥季节施药处理、春末夏初收获龙眼的调控方案较适合茂名等冬暖的地区。     

不同因素对杜仲叶绿原酸含量的影响

采用纸层析紫外分光光度法,对不同采收期、不同性别、不同干燥方法及不同贮藏时间杜仲叶绿原酸含量的动态变化进行了研究。     

杜仲叶中多酚类化合物含量与主要生态因子的相关性研究

本文考察了杜仲叶中总多酚、黄酮、绿原酸等多酚类化合物及京尼平苷酸、桃叶珊瑚苷含量等活性成分与其生态因子的相关性。利用聚类分析、主成分分析、相关分析、排序等统计方法进行分析,结果表明温度及蒸发量在杜仲叶中多酚类化合物等次生代谢物形成中起决定性作用,在一定范围内,温度及蒸发量越高越有利于杜仲叶中多酚类化合物及京尼平苷酸、桃叶珊瑚苷的累积;土壤中有效态铁、锌、锰含量及p H与多酚类化合物含量成正相关。在实践生产中可以通过适当选择高温度,提高蒸发量的地段,增施铁、锌、锰、硼肥料,适当调节土壤p H等农艺措施,提高杜仲叶中多酚类化合物等次生代谢物含量。     

葛花不同工艺提取物的异黄酮成分含量比较研究

目的:以不同浓度乙醇和大孔吸附树脂法提取和纯化葛花的提取物,并用HPLC和UV进行异黄酮成分含量比较分析。方法:以不同浓度的乙醇回流提取葛花药材制备提取物,并采用大孔吸附树脂对其进行纯化;然后以HPLC法对提取物中的3种主要黄酮类成分进行定量分析,并以UV法测定其总黄酮含量。结果:葛花不同提取物的黄酮类成分含量差别较大;所建立的HPLC方法可以同时测定葛花提取物中鸢尾苷、6"-O-木糖鸢尾苷和染料木素的含量;UV法与HPLC法联合应用,可对不同葛花提取物中的异黄酮类成分进行评价。结论:不同工艺提取的葛花提取物中异黄酮类成分有较大区别,大孔吸附树脂纯化后可显著提高总黄酮的纯度;HPLC联合UV法可共同用于葛花的质量评价及提取工艺的研究。     

杜仲叶的新用途

杜仲叶也具有补肝肾、强筋骨、活血、降血压功效。叶片也可作保健饮料及杜仲茶。用杜仲叶粉2.5％作鳝鱼的混合饵料,可改善和增加鳝鱼肉的蛋白胶原含     

The Levels of Nitrogen, Phosphorus, Potassium, Calcium and Magnesium in the Leaves of Cacao (Theobroma Cacao L.) as affected by Shade, Fertilizer, Irrigation, and Season

The results are given of chemical analyses of leaves collectedover a period of two years from cocoa trees in a field trialreceiving fertilizer, shade, and irrigation treatments. Thegreatest variation in concentration of nutrients in the leaveswas due to the time of year the leaves were collected. The lowestconcentrations of nitrogen, phosphorus, and potassium were foundin the leaves collected during the peak of the main season harvest.The highest levels of these elements were found in leaves collectednear the end or a few weeks after the end of the main harvest.The levels of calcium in the leaves were just opposite, withthe highest levels coinciding with harvest and the lowest levelsoccurring just after the harvest period. The levels of magnesiumshowed no marked variations between seasons. Shade increased the levels of nitrogen, phosphorus, and potassium,and decreased the levels of calcium in the leaves. Fertilizerincreased the levels of nitrogen, phosphorus, calcium, and magnesium,and decreased the level of potassium in the leaves. The effectof irrigation was small, but it decreased the levels of nitrogen,potassium, calcium, and magnesium in the leaves. The levels of nitrogen, phosphorus, and potassium in the leavesover the 21 harvesting times were found to be positively correlatedwith each other, and all three were negatively correlated withthe levels of calcium in the leaves over the same period. Noneof the levels of these four elements was significantly correlatedwith the levels of magnesium in the leaves over the period.     

Cabbage Seasonal Leaf Quality Mediating the Diamondback Moth Plutella xylostella (L.) (Lepidoptera: Yponomeutidae) Performance

Seasonal variation in plant quality may be intense enough to generate predictable patterns in insect herbivore populations. In order to explain seasonal oscillations in neotropical populations of the diamondback moth Plutella xylostella (L.), we tested the following: (1) if nutritional quality of cabbage (Brassica oleraceae var. capitata), a primary host plant of diamondback moth, adversely affects the performance of this insect in late spring and early summer, when populations decline and go extinct, and (2) if nutritional features of cabbage change with the seasons. We measured the performance of diamondback moth reared on leaves of cabbages grown during the four seasons of the year. Summer plants proved to be worse for the survival of the immature stages and subsequent adult fecundity, but there were no significant differences between the remaining seasons. Our results support the hypothesis that short-lived plants, grown in different seasons of the year in the tropics, have different nutritional and defensive attributes. We analyzed nutritional quality of cabbage leaves from the four seasons, but only total lipids were reduced in summer plants. Neotropical populations of diamondback moth collapse before plant quality decay in the summer. If the diamondback moth is well adapted to the seasonal deterioration of the habitat, including the reduction in the quality of host plants, it is expected that emigration happens before the mortality increases and natality decreases during the summer.     

182 Experimental Harvests of Five Species of Macroalgae Along the Oregon Coast

Macroalgae are the basis of a major global industry. Their nutritional and chemical values have brought strong economic pressure for commercial harvest permits to the State of Oregon, USA. Historically, Oregon has denied these requests because of a lack of understanding of harvest effects on the resource. Three species of phaeophytes ( Laminaria setchellii, Alaria marginata, Fucus gardneri ) and two rhodophytes ( Mastocarpus papillatus, Mazzaella splendens ) were subjected to various treatments to determine their ability to recover from harvest. Three year experiments were designed to compare the effects of harvesting during different seasons, different amounts, and different methods. Permanent transects and plots were placed in three study sites along the Oregon coast. Here we present the results from the first growing season. Only A. marginata was found to regain pre-harvest biomass within one growing season; all species will be monitored for regrowth and resettlement for the next two growing seasons to provide a basis for the management of the potential economic resource.     

A substance inducing teliospore production in wheat leaf rust,Puccinia recondita f. sp.tritici

A substance inducing teliospore production inPuccinia racondita f. sp.tritici was found in water and methanol extracts of wheat leaves with telia of the wheat leaf rust just before harvest time. Methanol (MeOH) and water extracts from uninfected wheat leaves also showed telia-inducing activity. However, the MeOH and water extracts from wheat leaves covered with telia showed much stronger activity than those from uninfected wheat leaves. We obtained a fraction (0.2 mg) showing activity at 2 ng/ml by purification of the water extract.     

Seasonal variation in antimicrobial and phytochemical properties of frequently used medicinal bulbous plants from South Africa

The growing popularity of traditional medicine and the unrestricted collection of medicinal plants from the wild have put many of the slow growing bulbous plant species at the risk of over-exploitation and extinction in South Africa. This study was aimed at comparing the phytochemical composition and biological (antibacterial and anticandidal) activities of bulb and leaf extracts of Tulbaghia violacea, Hypoxis hemerocallidea, Drimia robusta and Merwilla plumbea between spring, summer, autumn and winter seasons, with the view of promoting the use of leaves, as a conservation strategy. Antibacterial and anticandidal activities of petroleum ether (PE), dichloromethane (DCM), 80% ethanol and water extracts of bulbs and leaves were tested against Bacillus subtilis, Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae bacteria and the fungus Candida albicans using the microdilution bioassay. Spectrophotometric methods were used to evaluate saponin and phenolic compositions for the four seasons. Leaf and bulb extracts exhibited comparable anticandidal activity (MIC < 1 mg/ml) in all the plant species in all seasons. Only ethanol and water extracts of H. hemerocallidea corms (autumn and winter) showed correspondingly good fungicidal activity amongst the bulbs tested. Antibacterial activity was fairly comparable between bulbs and leaves with at least one extract of each plant species showing some good MIC values in most of the seasons. The best antimicrobial activities were recorded in winter and autumn seasons, with MIC values as low as 0.2 mg/ml in the DCM bulb extracts of T. violacea (winter) against K. pneumoniae and S. aureus. The amounts of total phenolic compounds in all plant samples were generally higher in spring compared to the other seasons. Condensed tannin, gallotannin and flavonoid levels, depending on the sample, were either higher in spring or winter except for H. hemerocallidea (corm) which had higher gallotannin levels in autumn. Total saponin levels were higher in winter in all plant samples. Although variation was observed in the phytochemical concentrations between the bulbs and leaves of each plant species, their antimicrobial activities were fairly comparable. Leaves may be used as substitutes for bulbs in the treatment of bacterial and fungal ailments.     

Leaf flavonoid content in Quercus ilex L. resprouts and its seasonal variation

Here, we provide the first report on flavonoid content in holm oak (Quercus ilex L.) leaves, analyzed by HPLC–MS/MS. Flavanols and flavonols were the predominant groups, although proanthocyanidins and many soluble tannins had a relevant presence in all leaf samples. Seasonal variation of flavonoids was determined in extracts from Q. ilex leaves during resprouting after a forest fire in two Mediterranean forests. Similar seasonal trends were observed over 2 years during the two main stress seasons (winter and summer). The most abundant flavonoid was the flavanol epicatechin, which showed similar values during the two seasons. Hexosides of the flavonols, quercetin, kaempferol and rhamnetin showed considerably higher content in winter, especially at the lowest temperatures. These variations in both forests are discussed on the basis of the chlorophyll fluorescence results obtained. Anthocyanins were found practically absent in mature leaves. Nutrient or water availability differences between sites or seasons were not related to changes in leaf flavonol-hexoside content.     

影响绿茶季节间品质差异的生化因子探析

通过测定同一生态环境下生长的31份茶树材料春、夏、秋3季1芽2叶时茶叶的主要生化成分,同时制作烘青茶样进行感官审评,并对测定数据进行统计分析,以揭示影响绿茶品质季节间差异的主要生化因子。结果表明,有27份材料的茶叶品质呈现出春季高于夏、秋季的变化趋势。对27份材料生化成分与品质总分的逐步回归分析、相关分析和通径分析表明,氨基酸、花青素和叶绿素含量对茶叶品质的影响最大,是导致绿茶品质季节间差异的主要生化因子。其中氨基酸表现为正向影响,在季节间呈现春季高、夏秋季降低的规律;花青素和叶绿素表现为负向影响,在季节间呈现春季低、夏秋季升高的趋势。     

影响暗黑鳃金龟成虫取食、寿命及生殖力的植物叶片营养成分分析

【目的】分析植物叶片中主要营养成分与暗黑鳃金龟Holotrichia parallela成虫取食偏好关系,明确影响其成虫取食、寿命及生殖力的主要营养成分。【方法】测定室内5种植物(花生、核桃、榆树、金叶女贞和毛白杨)叶片饲养的暗黑鳃金龟成虫寿命、取食量和产卵量,分析植物叶片中4种主要营养成分(氨基酸、脂肪酸、粗纤维和总磷)含量与暗黑鳃金龟成虫取食、寿命和生殖力之间的相关性。【结果】暗黑鳃金龟成虫对5种植物叶片的日均取食量由高到低依次为：花生>核桃>榆树>金叶女贞>毛白杨;取食核桃、花生和榆树叶片的成虫总取食量和单雌总产卵量与取食金叶女贞和毛白杨的成虫间均差异极显著(P<0.01)。成虫总取食量与植物叶片中氨基酸含量显著相关(P<0.05; r=0.515);成虫单雌总产卵量与植物叶片中脂肪酸及氨基酸含量间极显著相关(P<0.01)(分别为：r=0.698和r=0.746)。植物叶片中必需氨基酸含量与成虫取食量和产卵量相关性与植物叶片中总氨基酸含量与成虫取食量和产卵量的相关性基本一致;成虫取食量与植物叶片中赖氨酸含量最相关,而成虫单雌总产卵量与植物叶片中各种必需氨基酸含量均相关。成虫寿命与植物叶片营养成分含量不相关。【结论】植物叶片中的赖氨酸含量是影响暗黑鳃金龟成虫取食偏好的关键因子,植物叶片中必需氨基酸含量和脂肪酸含量影响暗黑鳃金龟生殖力。     

Interactions among leaf toughness, chemistry, and harvesting by attine ants

Abstract. 1. Young and mature leaves of a tropical legume, Inga edulis var. minutula Schery, are strikingly different in secondary chemistry, especially condensed tannins, and leaf toughness.
2. Bioassays with the two different leaf types indicate that leaf cutter ants, Atta cephalotes (L.), always find mature leaves relatively more acceptable than young leaves when selection was based on chemical cues.
3. Since extracts of young leaves show greziter inhibition of fungal pectinases we suggest that leaf-cutter ants are capable of distinguishing which leaf types are most suitable for the growth of their symbiotic fungus.
4. However, mature leaves are 3 times tougher than young leaves and this prevents leaf-cutter ants from harvesting the more suitable mature leaves.
5. Consequently, bioassays which require cutting before leaf removal indicate that some colonies actually harvest more from the less suitable young leaves.
6. We suggest that the quality of a colony's habitat may indicate whether a colony will harvest more of the less suitable young leaves. Colonies which are harvesting from highly suitable host plants avoid the tropical legume I.edulis while those in poorer habitats accept I.edulis but, because of leaf toughness, mostly harvest the less suitable young leaves.     

The Changes in Soluble Protein of Excised Barley Leaves during Senescence and Kinetin Treatment

Sterile detached barley leaves were floated on water or kinetin (10 mg/1)and supernatant extracts (30,000 x g for 30 min) were prepared from these leaves over an 8 day incubation period. Changes in selected total enzyme levels and in individual soluble protein components wore compared. Ribonuclease, deoxyribonuclease and peptidase activities rose in senescing leaves, even as total protein levels fell. Kinetin to some extent depressed these activities. Evidence of considerable loss of ribonuclease and to a lesser extent of deoxyribonuclease into the surrounding medium was obtained. Soluble supernatant ant extracts were resolved on DEAE-Sephadex (A-50) columns into about 15 components. While most components were degraded during senescence they did so at different rates. Kinetin lowered the rate of degradation of all components. Since no conclusive evidence of a new protein(s) was obtained in water and kinetin treated leaves, it was considered that any protein changes may have been of a quantitative rather than qualitative nature.