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Screening for Hypoglycemic Activity on The Leaf Extracts of Nine Medicinal Plants: In-Vivo Evaluation 九种药用植物叶片提取物降血糖活性的筛选:体内评价
Pub Date : 2012-08-01 DOI: 10.1155/2012/103760
A. Arya, M. Abdullah, Batoul Sadat
The traditional use of certain plants by the tribal community in central India involves using the young leaves for several ailments, including hyperglycaemia; this study was performed to evaluate the effects of the leaf extracts from 9 such plants in the management of diabetes. Initially, hypoglycemic screening was performed on normal rats whose blood glucose levels were measured before and after oral or intraperitoneal (i.p.) administration of the extracts at different periods. The plants were screened at doses of 250 mg/kg i.p. or 500 mg/kg orally. Of these, only Centratherum anthelminticum (Asteraceae), Cissus quadrangularis (Vitaceae), and Woodfordia fruticosa Kurz (Lythraceae) significantly reduced postprandial blood glucose levels in normal glycemic rats (P <0.001), with slight reductions effected by Sida acuta Burm F. (P = 0.002) and Parthenium hysterophorus L. (P = 0.017). The extracts that reduced postprandial blood glucose levels both orally and i.p. in the hypoglycemic screening tests were evaluated for glucose challenge in glucose tolerance tests with i.p and oral administration in overnight-fasted normal rats. The results of these tests potentiate the screening data in the management of diabetes mellitus, which requires further studies on the plants that yielded positive results to determine the active compounds in the different plant parts that are responsible for the activity.
印度中部部落社区对某些植物的传统使用包括用嫩叶治疗几种疾病,包括高血糖;本研究评估了9种此类植物叶片提取物在糖尿病治疗中的作用。首先,对正常大鼠进行低血糖筛查,在不同时期口服或腹腔给药前后测量血糖水平。筛选剂量分别为250 mg/kg和500 mg/kg。其中,只有紫菀(Asteraceae)、猕猴桃(quissus quadrangularis)和木fordia fruticosa Kurz (Lythraceae)能显著降低正常血糖大鼠的餐后血糖水平(P <0.001),而Sida acuta Burm F. (P = 0.002)和Parthenium hysterophorus L. (P = 0.017)有轻微的降低作用。在空腹过夜的正常大鼠的糖耐量试验中,通过口服和口服给药来评估在降糖筛选试验中口服和口服降低餐后血糖水平的提取物对葡萄糖的影响。这些试验的结果增强了糖尿病管理的筛选数据,这需要对产生阳性结果的植物进行进一步的研究,以确定不同植物部位中负责活性的活性化合物。
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引用次数: 36
Preparation and Characterization of Chitosan/Agar Blended Films: Part 2. Thermal, Mechanical, and Surface Properties 壳聚糖/琼脂混合膜的制备与表征:第2部分。热,机械和表面性能
Pub Date : 2012-04-16 DOI: 10.1155/2012/285318
E. A. Elhefian, M. Nasef, A. Yahaya
Chitosan/agar (CS/AG) films were prepared by blending different proportions of chitosan and agar (considering chitosan as the major component) in solution forms. The thermal stability of the blended films was studied using thermal gravimetric analysis (TGA). It was revealed that chitosan and agar form a compatible blend. Studying the mechanical properties of the films showed a decrease in the tensile strength and elongation at break with increasing agar content. Blending of agar with chitosan at all proportions was found to form hydrogel films with enhanced swelling compared to the pure chitosan one. Static water contact angle measurements confirmed the increasing affinity of the blended films towards water suggesting that blending of agar with chitosan improves the wettability of the obtained films.
以壳聚糖为主要成分,将不同比例的壳聚糖与琼脂溶液混合,制备了壳聚糖/琼脂(CS/AG)膜。采用热重分析(TGA)对共混膜的热稳定性进行了研究。结果表明,壳聚糖与琼脂形成了一种相容性良好的共混物。对薄膜力学性能的研究表明,随着琼脂含量的增加,薄膜的抗拉强度和断裂伸长率下降。与纯壳聚糖相比,琼脂与壳聚糖以各种比例混合形成的水凝胶膜具有增强的膨胀性。静态水接触角测试证实了混合膜对水的亲和力增加,这表明琼脂与壳聚糖的混合提高了所得到的膜的润湿性。
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引用次数: 51
Preparation and Characterization of Chitosan/Agar Blended Films: Part 1. Chemical Structure and Morphology 壳聚糖/琼脂混合膜的制备与表征:第1部分。化学结构与形态
Pub Date : 2012-04-13 DOI: 10.1155/2012/781206
E. A. Elhefian, M. Nasef, A. Yahaya
Chitosan/agar (CS/AG) films were prepared by blending different proportions of chitosan and agar (considering chitosan as the main component) in solution forms. The chemical structure and the morphology of the obtained blended films were investigated using Fourier transform infrared (FTIR) and field emission scanning electron microscope (FESEM). It was revealed that chitosan and agar form a highly compatible blend and their films displayed homogenous and smooth surface properties compared to the individual pure components.
以壳聚糖为主要成分,将不同比例的壳聚糖与琼脂溶液混合,制备了壳聚糖/琼脂(CS/AG)膜。利用傅里叶变换红外(FTIR)和场发射扫描电镜(FESEM)研究了混合膜的化学结构和形貌。结果表明,壳聚糖和琼脂形成了一种高度相容的共混物,与单独的纯组分相比,它们的膜具有均匀和光滑的表面特性。
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引用次数: 58
Characterization of Extracellular Dextranase from a Novel Halophilic Bacillus subtilis NRC-B233b a Mutagenic Honey Isolate under Solid State Fermentation 新型嗜盐枯草芽孢杆菌NRC-B233b致突变蜂蜜分离物胞外葡聚糖酶的固态发酵特性
Pub Date : 2012-04-13 DOI: 10.1155/2012/860619
M. Esawy, Sara H. Mansour, E. Ahmed, N. M. Hassanein, H. E. Enshasy
Bacillus subtilis NRC-B233b was isolated from Libyan honey sample proved to be a potent dextranase producer by applying solid state fermentation and utilizing corn flour as the sole carbon source. The optimized culture conditions for dextranase productions were 37°C, pH 10, 32 h, and 20% (v/w) moisture content. A unique character of this isolate is its ability to produce steady dextranase irrespective to the presence of NaCl in the medium. The addition of 0.175 Mm CrCl3 increased the enzyme production by about 4.5 fold. Further improvement in enzyme production was achieved by simple UV mutation which increased the enzyme production up to about 2842 U/g. The crude extract has been partially purified about 112-fold from crude extract by only two purification steps involving ultra-filtration. The partially purified dextranase showed its maximum activity at pH 9.2 and 70°C. It retained full activity (100%) at 75°C for one hour. Dextranase activity increased about 4 fold in the presence of 10% NaCl. This enzyme showed variable degradation effect on different types of dextran and its derivatives. The treatment of viscous sugar cane juice with the enzyme preparation resulted in clear visual dextran hydrolysis. These results suggest that the dextranase produced by Bacillus subtilis NRC-B233b is industrially applicable.
从利比亚蜂蜜样品中分离到枯草芽孢杆菌NRC-B233b,以玉米粉为唯一碳源,采用固态发酵的方法,证实了枯草芽孢杆菌NRC-B233b是一种有效的葡聚糖酶产生菌。葡聚糖酶的最佳培养条件为37℃、pH 10、32 h、20% (v/w)的含水量。该分离物的一个独特特性是无论培养基中是否存在NaCl,它都能产生稳定的葡聚糖酶。添加0.175 Mm CrCl3可使酶产量提高约4.5倍。通过紫外诱变进一步提高了酶的产量,使酶的产量提高到2842 U/g左右。粗提取物仅通过两个涉及超滤的纯化步骤就从粗提取物中部分纯化了约112倍。部分纯化的葡聚糖酶在pH 9.2和70℃条件下活性最高。在75℃下保存1小时,仍能保持100%的活性。10% NaCl处理下,葡聚糖酶活性提高了约4倍。该酶对不同类型葡聚糖及其衍生物具有不同的降解作用。用该酶制剂对粘性甘蔗汁进行处理后,葡聚糖水解效果明显。这些结果表明,枯草芽孢杆菌NRC-B233b生产的葡聚糖酶具有工业应用价值。
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引用次数: 29
Comparison of Catalysts Preyssler and Silica-Supported Nano Preyssler in the Synthesis of Acetyl Salicylic Acid 催化剂Preyssler与二氧化硅负载纳米Preyssler合成乙酰水杨酸的比较
Pub Date : 2012-01-12 DOI: 10.1155/2012/892861
Hadiseh Nazari, A. Ahmadpour, F. Bamoharram, M. Heravi, N. Eslami
The extensive demand for cleaner environment is forcing chemical industry to use less hazardous materials. In this regard, heteropolyacids attracted considerable amount of interest due to the less toxic behavior in addition of possessing higher acidity. Heteropoly acids have been used as catalysts for the reaction of salicylic acid with acetic anhydride. The performance of different forms of heteropoly acids in the presence of acetic anhydride as acetylating agent for acetylation of salicylic acid was compared. The best conditions were observed using Preyssler and Silica-supported Preyssler Nanoparticles as catalysts. The catalyst is recyclable and reusable.
对清洁环境的广泛需求迫使化学工业使用更少有害的材料。在这方面,杂多酸由于具有较高的酸度和较低的毒性而引起了相当大的兴趣。以杂多酸为催化剂,对水杨酸与乙酸酐的反应进行了研究。以乙酸酐为乙酰化剂,比较了不同形式杂多酸对水杨酸乙酰化反应的性能。以Preyssler和二氧化硅负载的Preyssler纳米颗粒作为催化剂,观察到最佳条件。催化剂可回收再利用。
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引用次数: 1
Direct Electrochemical Synthesis of Bismuth(III) Phenoxides and their Coordination Compounds 铋(III)苯氧化物及其配位化合物的直接电化学合成
Pub Date : 2012-01-01 DOI: 10.1155/2012/403782
H. Kaur, Baljit Singh
Bismuth(III) phenoxides have been synthesized by electrochemical reactions of 1-naphthol, 2-naphthol, 4-aminophenol, 2-nitrophenol, 4-nitrophenol, 2-hydroxybenzoic acid, p-cresol, phenol, resorcinol, 2-tert-butylphenol and 2-tert-butyl-4-methoxyphenol at sacrificial bismuth anode and inert platinum cathode using tetrabutylammonium chloride as supporting electrolyte. The coordination compounds of these phenols with 1, 10-phenanthroline and 2, 2ʼ-bipyridyl have also been synthesized electrochemically. The solid products separated in the anode compartment have been isolated and characterized by elemental analysis and infrared spectral studies. Current efficiencies of these reactions are quite high.
以四丁基氯化铵为支撑电解质,在牺牲铋阳极和惰性铂阴极上,以1-萘酚、2-萘酚、4-氨基酚、2-硝基酚、4-硝基酚、2-羟基苯甲酸、对甲酚、苯酚、间苯二酚、2-叔丁基苯酚和2-叔丁基-4-甲氧基苯酚为电化学反应合成了铋(III)苯氧化合物。这些酚类化合物与1,10 -菲罗啉和2,2′-联吡啶的配位化合物也被电化学合成。通过元素分析和红外光谱研究,对阳极室中分离的固体产物进行了分离和表征。目前这些反应的效率相当高。
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引用次数: 3
Production of oleic acid based wax ester using acidic homogeneous catalysts 酸性均相催化剂制备油酸基蜡酯
Pub Date : 2012-01-01 DOI: 10.1155/2012/181249
Naowara M. Al-Arafi, J. Salimon
Four homogeneous acidic catalysts were tested for their ability to catalyze the esterification reaction of oleic acid and oleyl alcohol to produce oleyl oleate, a wax ester. Sulfuric acid showed relatively higher specific activity. Various reaction parameters were optimised to obtain high percentage yield of oleyl oleate. The optimum condition to produce oeyl oleate was reaction time; 5 h, temperture; 90°C, amount of sulforic acid 0.15 g and molar ratio of oleyl alcohol to oleic acid; 1:1. Percentage yield of wax ester obtained at these optimum reaction conditions was 93.88. Disappearance of carboxylic acid (C=O) peak has confirmed by FTIR with appearance of ester (C=O) peak at 1739 cm−1. 1H NMR spectra analyses confirmed the result of oleyl oleate with appearance of ester (-CH2OCOR) at 4.02 ppm and also the 13C-NMR confirmed the result with appearance of ester (C=O) peak at 173.2 ppm. The low-temperture behavior of compound synthesized was determined through its pour point (PP), viscosity index (VI) and flash point (FP) values. The results showed that oleyl oleate exhibited the most favorable low-temperture performance of PP, VI and FP with −31°C, 197.5 and 320°C respectively. This is due to increase of the molacular weight thus improve the low temperture property significantly.
研究了四种均相酸性催化剂催化油酸和油醇酯化反应生成油酸油酯(一种蜡酯)的能力。硫酸表现出较高的比活性。优化了各种反应参数,以获得高收率的油酸油酯。制备油酸油脂的最佳工艺条件为反应时间;5 h,温度;90℃,硫酸用量0.15 g,油醇与油酸的摩尔比;1:1。在此条件下制得的蜡酯收率为93.88。FTIR证实羧酸(C=O)峰消失,在1739 cm−1处出现酯(C=O)峰。1H NMR谱分析证实油酸酯在4.02 ppm处有酯(-CH2OCOR)的形貌,13C-NMR在173.2 ppm处也有酯(C=O)的形貌。通过浇注点(PP)、粘度指数(VI)和闪点(FP)值测定所合成化合物的低温行为。结果表明,在- 31℃、197.5℃和320℃的低温条件下,油酸油酯对PP、VI和FP的低温性能最有利。这是由于增加了分子量,从而显著改善了低温性能。
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引用次数: 9
The Effects of Silica/Carbon Black Ratio on the Dynamic Properties of the Tread compounds in Truck Tires 二氧化硅/炭黑配比对载重轮胎胎面胶动态性能的影响
Pub Date : 2012-01-01 DOI: 10.1155/2012/571957
R. Zafarmehrabian, Saeed Taghvaei Gangali, M. Ghoreishy, Mehran Davallu
NR is the major constituent in the rubber compound used for the tread on the truck tires. A general compound formulation of the tire tread includes NR and BR as polymer base and carbon black as the reinforcing filler, and curative components. In this paper the effects of dual filler system (carbon black and precipitated silica) on the dynamic properties of tire treat has been studied. The results show by increasing of precipitated silica, significant improvement was observed in fatigue resistance, rolling resistance and heat buildup of the tire. Tensile strength and modulus and wet grip of tire tread decrease with increasing of silica in rubber compound formulation.
天然橡胶是用于卡车轮胎胎面的橡胶化合物的主要成分。一般的轮胎胎面复合配方包括以NR和BR为聚合物基,以炭黑为补强填料,以及硫化组分。本文研究了双填料体系(炭黑和沉淀二氧化硅)对轮胎胶动态性能的影响。结果表明,通过增加析出二氧化硅的含量,轮胎的抗疲劳性能、抗滚动性能和积热性能均有明显改善。随着橡胶复合配方中二氧化硅含量的增加,轮胎胎面抗拉强度、模量和湿抓地力下降。
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引用次数: 59
Solvent-Free Synthesis of 1,8-Dioxo-octahydroxanthenes and 14-Aryl-14H-dibenzo[a,j]xanthenes using Saccharin SulfonicAcid as an Efficient and Green Catalyst 糖精磺酸催化无溶剂合成1,8-二氧八羟基蒽和14-芳基- 14h -二苯并[a,j]杂蒽
Pub Date : 2012-01-01 DOI: 10.1155/2012/596862
A. Zare, M. Mokhlesi, A. Hasaninejad, Tahereh Hekmat-Zadeh
Saccharin sulfonic acid (SaSA) is utilized as a highly efficient, green and inexpensive sulfonic acid-containing catalyst for the following one-pot multi-component organic transformations: (i) the condensation of dimedone (2 eq.) with aromatic aldehydes (1 eq.) leading to 1,8-dioxo-octahydroxanthenes, and (ii) the reaction of 2-naphthol (2 eq.) with arylaldehydes (1 eq.) leading to 14-aryl-14H-dibenzo[a,j]xanthenes. In these protocols, the title compounds are produced in high to excellent yields and in relatively short reaction times under solvent-free conditions.
糖精磺酸(SaSA)是一种高效、绿色、廉价的含磺酸催化剂,可用于以下一锅多组分有机转化:(i)二美酮(2 eq.)与芳香醛(1 eq.)缩合得到1,8-二氧八羟基蒽,(ii) 2萘酚(2 eq.)与芳醛(1 eq.)反应得到14-芳基- 14h -二苯并[a,j]杂蒽。在这些方案中,标题化合物在无溶剂条件下以高至优异的收率和相对较短的反应时间生产。
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引用次数: 12
Thermodynamic and Isotherm Analysis on the Removal of Malachite Green Dye Using Thespesia Populnea Bark 白杨树皮脱除孔雀石绿染料的热力学及等温线分析
Pub Date : 2012-01-01 DOI: 10.1155/2012/629089
R. Prabakaran, S. Arivoli
Activated carbon was synthesized from Thespesia Populnea Bark, a low cost material, by sulphuric acid activation; it was tested for its ability to eliminate malachite green in aqueous solution. The parameters studied included contact time, initial dye concentration, carbon dose, pH and temperature. The adsorption followed first order rate equation. In addition, it was found that the adsorption process was described by Freundlich and Langmuir isotherm models. Those models were applied to the equilibrium data. The absorption capacities (Qm) obtained from the Langmuir isotherm plots were 349.20, 365.43, 476.44, and 389.96 mg/g at 30°, 40°, 50°, and 60°C, respectively, at an initial pH 6.0. The temperature variation study showed that the malachite green dye absorption was endothermic and spontaneous with increased randomness at the solid solution interface. The thermodynamic parameters like ∆H°, ∆S°, and ∆G° were calculated from the slope and intercept of the linear plots.
以廉价原料白杨树皮为原料,采用硫酸活化法制备活性炭;对其在水溶液中去除孔雀石绿的能力进行了测试。研究的参数包括接触时间、初始染料浓度、碳量、pH和温度。吸附符合一级速率方程。此外,还发现吸附过程可以用Freundlich和Langmuir等温模型描述。将这些模型应用于平衡数据。Langmuir等温线图在30°、40°、50°和60°C条件下的吸光度(Qm)分别为349.20、365.43、476.44和389.96 mg/g,初始pH为6.0。温度变化研究表明,孔雀石绿对染料的吸收是吸热自发的,在固溶界面处随机性增加。根据线性图的斜率和截距计算出∆H°、∆S°、∆G°等热力学参数。
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引用次数: 8
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E-journal of Chemistry
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