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71.
The objectives of the present study were to develop a simple high performance thin layer chromatography (HPTLC)-based protocol: (i) to allow high-throughput profiling of phenolic compounds of microwaved roots from 295 sweet potato varieties and breeding lines, (ii) to quantify the content of anthocyanins and caffeoylquinic acid (CQA) derivatives, and (iii) to determine their respective contributions to the antioxidant activity of sweet potato methanolic extracts using the DPPH test. Analysed accessions were separated into three groups: white-fleshed (n = 100), orange-fleshed (n = 64) and purple-fleshed (n = 131). Purple-fleshed accessions presented the highest mean CQA content. After DPPH treatment and transmittance scanning of the plate at 517 nm, the most active free radical scavengers were found to be the four CQAs (CGA, 3,4-, 4,5- and 3,5-diCQA) while the anthocyanins were found to be less active. The total antioxidant capacity of the sweet potato methanolic extracts was mostly linked to total CQAs content. This method can now be used for fast routine analysis and selection of sweet potato breeding clones.  相似文献   
72.
Analysis of the complex composition of cocoa beans provides fundamental information for evaluating the quality and nutritional aspects of cocoa-based food products, nutraceuticals and supplements. Cameroon, the world’s fourth largest producer of cocoa, has been defined as “Africa in miniature” because of the variety it habitats. In order to evaluate the nutritional characteristics of cocoa beans from five different regions of Cameroon, we studied their polyphenolic content, volatile compounds and fatty acids composition. The High Performance Thin Layer Chromatography (HPTLC) analysis showed that the Mbalmayo sample had the highest content of theobromine (11.6?mg/g) and caffeic acid (2.1?mg/g), while the Sanchou sample had the highest level of (?)-epicatechin (142.9?mg/g). Concerning fatty acids, the lowest level of stearic acid was found in the Mbalmayo sample while the Bertoua sample showed the highest content of oleic acid. Thus, we confirmed that geographical origin influences the quality and nutritional characteristics of cocoa from these regions of Cameroon.  相似文献   
73.
Interactions between neurons and astrocytes play a critical role in the central nervous system homeostasis. Cyperus rotundus (family: Cyperaceae), a traditional Indian medicinal herb, used as nervine tonic and nootropic in the Ayurvedic system of medicine. The present study was undertaken to investigate the neuroprotective effect of total oligomeric flavonoids (TOFs), prepared from C. rotundus, in rat model of cerebral ischemia and reperfusion. Male Sprague Dawley rats (290-340 g) were subjected to middle cerebral artery occlusion (MCAO) for 2 h and reperfusion for 70 h. Experimental animals were divided into four groups: Group I - sham operated (n = 7); Group II - vehicle treated ischemic-reperfusion (IR) (n = 9), and Group III and IV - TOFs treated (100 and 200 mg/kg body weight, p.o., respectively; n = 7 in each group). Vehicle or TOFs were pretreated for four days before the induction of ischemia and continued for next three days after the ischemia i.e. treatment was scheduled totally for a period of 7 days. MCAO surgery was performed on day 4, 1 h after TOFs administration. Neuroprotective effect of TOFs was substantiated in terms of neurological deficits, excitotoxicity (glutamate, glutamine synthetase and Na+K+ATPase levels), oxidative stress (malondialdehyde, super oxide dismutase, and glutathione) and neurobehavioral functions in the experimental animals. TOFs decreased glutamate, glutamine synthetase (GS) and increased Na+K+ATPase activity in a dose dependent manner when compared to the IR rats. Treatment with TOFs significantly reduced the neurological deficits and reversed the anxiogenic behavior in rats. Further, it also significantly decreased MDA and increased superoxide dismutase (SOD) and glutathione content in brains of experimental rats. Histopathological examination using cresyl violet staining revealed the attenuation of neuronal loss by TOFs in stroke rats. The present study demonstrates the unswerving involvement of TOFs on ischemia-reperfusion triggered biochemical alterations in MCAO/R rats. Hence, TOFs might be an attractive candidate for further studies in the development of new drugs for cerebral stroke treatment.  相似文献   
74.
刘硕  丁平  应鸽  代蕾 《华西药学杂志》2012,27(4):434-435
目的以巴戟天药材生品为基础,建立巴戟天不同炮制品的高效薄层色谱(HPTLC)指纹图谱,并比较分析生品的指纹图谱。方法硅胶GF254高效预制薄层板,乙酸乙酯部位以石油醚-乙酸乙酯(5∶5.5)为展开剂,上行展开8 cm,10%硫酸乙醇溶液显色;正丁醇部位以正丁醇-冰醋酸-水(4∶1∶5)上层溶液为展开剂,上行展开8 cm,α-萘酚浓硫酸试剂显色。显色后置紫外光灯365 nm或自然光下检视,得薄层色谱指纹图谱,并进行相关分析。结果巴戟天生品的薄层荧光色谱指纹图谱与巴戟肉(蒸制)、盐巴戟天、制巴戟天(甘草制)图谱比较分析,彼此具有明显的区别,可用于生品与巴戟天炮制品的鉴别。结论通过HPTLC指纹图谱考察,生品巴戟天与巴戟肉、盐巴戟天、制巴戟天的区别较大,应分别制定质量评价的标准。  相似文献   
75.
《Pharmaceutical biology》2013,51(12):1397-1404
Context: Withania coagulans Dunal. (Solanaceae) has been shown to possess hypoglycemic, free radical scavenging and wound healing activity. Therefore, it may be worthwhile to study the effect of Withania coagulans in diabetic wound healing.

Objective: This study included determination of rate of wound contraction and estimation of various biochemical parameters such as collagen, hexosamine, total protein, total DNA, SOD and CAT levels in the granulation tissues.

Materials and methods: The hydroalcoholic fraction of the methanolic extract (standardized by withaferin-A using high performance thin layer chromatography (HPTLC) )of Withania coagulans in the form of 10% w/w ointment topically and at a dose of 500?mg/kg per oral (p.o.) was administered to streptozotocin-induced diabetic rats. The results obtained were compared with diabetic control and Aloe barbadensis Miller (syn. Aloe vera L.) (Liliaceae) was used as a reference drug.

Results: The amount of withaferin-A present in the methanolic extract was 3.67?mg/g of the extract. The hydroalcoholic fraction in both the forms, i.e., topical (10% w/w ointment) and oral (500?mg/kg, p.o.) showed a significant increase in the rate of wound contraction (83.02% topical and 65.14% oral) topical and 93.18% oral) when compared to diabetic control (66which was further justified with significant increase in the levels of collagen, protein, DNA, SOD, CAT, and decreased level of hexosamine.

Discussion and conclusion: The hydroalcoholic fraction of Withania coagulans in oral form is found to be more effective than the topical form. However, further studies are in progress to find the lead molecules responsible for the wound healing effect.  相似文献   
76.
Traditional Chinese medicine (TCM) has been widely used in China for thousands of years, and has received more and more recognition worldwide. Indigoplant (Folium Polygoni Tinctorii), a TCM, has been used in various diseases. In our study, we established a quality standard of Indigoplant according to the European Pharmacopoeia, and this standard has passed the early audit stages of the European Pharmacopoeia Commission. The Indigoplant samples were identified with high performance thin layer chromatography (HPTLC), qualified with RP-HPLC quantitation, and analyzed with a series of quality tests. An accurate, reliable and robust HPLC method with gradient elution for quantitation was developed and validated with a one-variable-at-a-time (OVAT) robustness approach. Several tests, including the loss on drying, total ash and ash insoluble in hydrochloric acid of Indigoplant, were performed for quality analysis. Furthermore, six batches of the Indigoplant samples were appraised with this quality standard. In conclusion, the established quality standard was more internationally normative and applicable for the quality control of Indigoplant in practical application.  相似文献   
77.

Ethnopharmacological relevance

Phyllanthus amarus Schum. &; Thonn. belongs to the family Euphorbiaceae is a small herb well known for its medicinal properties and widely used worldwide. P. amarus is an important plant of Indian Ayurvedic system of medicine which is used in the problems of stomach, genitourinary system, liver, kidney and spleen. It is bitter, astringent, stomachic, diuretic, febrifuge and antiseptic. The whole plant is used in gonorrhea, menorrhagia and other genital affections. It is useful in gastropathy, diarrhoea, dysentery, intermittent fevers, ophthalmopathy, scabies, ulcers and wounds.

Materials and methods

The present review covers a literature across from 1980 to 2011. Some information collected from traditional Ayurvedic texts and published literature on ethanomedicinal uses of Phyllanthus amarus in different countries worldwide.

Results

Phytochemical studies have shown the presence of many valuable compounds such as lignans, flavonoids, hydrolysable tannins (ellagitannins), polyphenols, triterpenes, sterols and alkaloids. The extracts and the compounds isolated from P. amarus show a wide spectrum of pharmacological activities including antiviral, antibacterial, antiplasmodial, anti-inflammatory, antimalarial, antimicrobial, anticancer, antidiabetic, hypolipidemic, antioxidant, hepatoprotective nephroprotective and diurectic properties.

Conclusion

The present review summarizes information concerning the morphology, ecology, ethnopharmacology, phytochemistry, biological activities, clinical applications and toxicological reports of P. amarus. This review aims at gathering the research work undertaken till date on this plant in order to provide sufficient baseline information for future works and commercial exploitation.  相似文献   
78.
The hydroalcoholic extract of fruit pulp of Terminalia chebula Retz. was standardized and evaluated for its safety through cytochrome P450 (CYP 450) inhibition assay. Standardization was performed through high performance thin layer chromatography (HPTLC) using gallic acid (GA) standard. Cytochrome P450‐CO complex microplate assay was performed using rat liver microsomes. The effect of standardized extract, its fraction and bioactive marker compound were comparatively evaluated for its effect on CYP P450 enzymes. The extract of fruit pulp was used for HPTLC, where the Rf value of the marker was found to be 0.43. The calibration plot was linear in the range of 2–14 µg of GA and correlation co‐efficient of 0.99965. The mean quantity of GA was found to be 2.5% w/w. The CYP P450 concentration of the rat liver microsome sample used in the study was found to be 0.417 nmol/mg protein. The in vitro effect of various concentrations of extracts and fractions showed a linear concentration‐dependent inhibition of cytochrome P450 up to 60 µL. The study showed more inhibition of fraction when compared to the extract and GA. Still, the inhibition showed by fraction is less when compared with standard Ketoconazole. Thus, this study indicated the in vitro cytochrome P450 inhibition potential of T. Chebula.  相似文献   
79.
AIM:In order to identify the HPTLC profile(bio-marker),at species level,for the identification and confirmation of crude drugs,HPTLC separation was initiated on different parts of Aerva lanata L.from South India.METHODS:Preliminary phyto-chemical screening was done by the method of Harborne.HPTLC studies were carried out following Harborne and Wagner et al method.The Ethyl acetate-ethanol-water(8:2:1.2)was employed as mobile phase for glycosides.RESULTS:The methanolic extract of stem,leaves,root,flowers and...  相似文献   
80.
Analytical methods including HPLC, UPLC and HPTLC are presented for the determination of major alkaloid and triterpene saponins from the roots of Caulophyllum thalictroides (L.) Michx. (blue cohosh) and dietary supplements claiming to contain blue cohosh. A separation by LC was achieved using a reversed phase column, PDA with ELS detection, and ammonium acetate/acetonitrile gradient as the mobile phase. Owing to their low UV absorption, the triterpene saponins were detected by evaporative light scattering. The eight triterpene saponins (cauloside H, leonticin D, cauloside G, cauloside D, cauloside B, cauloside C, cauloside A and saponin PE) and the alkaloid magnoflorine could be separated within 35 min using HPLC method and within 8.0 min using UPLC method with detection limits of 10 μg/mL for saponins and 1 μg/mL for magnoflorine. The detection wavelength was 320 nm for magnoflorine and ELS detection was used for the eight saponins. The methods were also successfully applied to analyze different dietary supplements. For the products claiming to contain blue cohosh, there was a significant variability in the amounts of triterpene saponins detected. Calculations based on the analysis results for dietary supplements showed that maximum daily intake of alkaloid and saponins vary with the form (solids/liquids) and recommended doses according to the products label. Intakes varied from 0.57 to 15.8 mg/day for magnoflorine and from 5.97 to 302.4 mg/day for total saponins. LC-mass spectrometry coupled with electrospray ionization (ESI) method is described for the identification and confirmation of nine compounds in plant samples and dietary products. A HPTLC method was also developed for the fast chemical fingerprint analysis of C. thalictroides samples.  相似文献   
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