甘薯长喙壳菌毒素检测的高效薄层色谱法研究

用乙醚提取甘薯毒素 ,提取物分别用 5 %的Na2CO3 和蒸馏水洗涤 ,无水硫酸钠干燥 ,蒸去乙醚。残渣 (粗品 )采用高效薄层色谱法进行检测 ,以纯品甘薯酮和甘薯酮醇作标样。结果表明 :在 2 0℃条件下在石油醚 醋酸乙酯 (2∶1 ,v v)溶剂系统中 ,对甘薯酮 (C)、甘薯酮醇 (A)等毒素有较好的分离效果 ,Rf 值的重复性也较好。展开后的薄层板通过CS 930薄层扫描仪在 52 0nm下扫描定量。采用高效薄层色谱法检测甘薯酮及甘薯酮醇 ,最低检测限量 :纯品为 0 0 0 2 μg,粗品为 0 0 1 μg。     

Author index for volume 86

The major neutral and acidic cerebellar lipids were studied in audiogenic seizure (AGS)-resistant $\text{C57BL}\text{6}$ (B6) and AGS-susceptible $\text{DBA}\text{2J}$ (D2) mice. These cerebellar lipids were also studied in the D2.B6-Ias^b congenic mice and in the B6D2F₁ hybrids that are mostly AGS resistant. Except for the Ias^b gene, which inhibits AGS susceptibility, the D2.B6-Ias^b congenic mice are genetically similar to the D2 mice. Because subtle abnormalities in the chemical structure of membranes may underlie epilepsy, we wanted to determine if AGS susceptibility was associated with abnormalities in the distribution of cerebellar lipids. A new method for the analysis of total brain lipids was used in this study. Slight, but significant, differences were found between the B6 and D2 strains for the concentrations (μg/100 mg wet weight) of sphingomyelin, phosphatidylcholine, and cerebrosides. However, these differences may not be associated with differences in AGS susceptibility since the concentrations of these lipids in the AGS-resistant D2.B6-Ias^b and B6D2F₁ mice were more similar to the D2 than the B6 concentrations. The expression of Ias^b is not responsible for the lipid differences found between the B6 and D2 mice.     

Morpho-anatomical and physicochemical studies of Fumaria indica (Hausskn.) Pugsley

Objective

To study morpho-anatomical characters and physicochemical analysis of Fumaria indica (F. indica) (Hausskn.) Pugsley, (Fumariaceae), an important medicinal plant used extensively for treating a variety of ailments in various system of indigenous medicine.

Methods

Evaluation of the different parts of the plant was carried out to determine the morpho-anatomical, physicochemical, phytochemical and HPTLC fingerprinting profile of F. indica and other WHO recommended methods were performed for standardization.

Results

Morpho-anatomical studies showed compound and pinnatifid leaf, 4 to 6 cm in length, linear and oblong in shape and anomocytic arrangement of stomata, thin walled parenchymatous cells, scattered, sclerenchymatous, capped vascular bundles and radiating medullary rays. Physicochemical studies showed foreign matter 0.2%, loss on drying 6.8%, total ash 16.77%, alcohol and water soluble extractives 8.92% and 20.26%, respectively, sugar 17.75%, starch 22.97% and tannins 2.37%. Phytochemical evaluation revealed the presence of carbohydrate, alkaloids, flavonoids, saponins, tannins and sterol. Thin layer chromatography was carried out with different solvents and the best solvent system was chloroform and methanol in 80:20 ratio and revealed 12 spots with different R_f value under UV light 366λ.

Conclusions

The results of the study can serve as a valuable source of information and provide suitable standards for identification of this plant material for future investigations and applications.     

Stability-indicating HPTLC determination of imatinib mesylate in bulk drug and pharmaceutical dosage form

A simple, selective, precise and stability-indicating high-performance thin-layer chromatographic method of analysis of imatinib mesylate both as a bulk drug and in formulations was developed and validated. The method employed HPTLC aluminium plates precoated with silica gel 60F-254 as the stationary phase. The solvent system consisted of chloroform:methanol (6:4, v/v). The system was found to give compact spot for imatinib mesylate (R(f) value of 0.53+/-0.02). Densitometric analysis of imatinib mesylate was carried out in the absorbance mode at 276 nm. The linear regression analysis data for the calibration plots showed good linear relationship with r(2)=0.9966+/-0.0013 with respect to peak area in the concentration range 100-1000 ng per spot. The mean value+/-S.D. of slope and intercept were 164.85+/-0.72 and 1168.3+/-8.26 with respect to peak area. The method was validated for precision, recovery and robustness. The limits of detection and quantitation were 10 and 30 ng per spot, respectively. Imatinib mesylate was subjected to acid and alkali hydrolysis, oxidation and thermal degradation. The drug undergoes degradation under acidic, basic, oxidation and heat conditions. This indicates that the drug is susceptible to acid, base hydrolysis, oxidation and heat. Statistical analysis proves that the method is repeatable, selective and accurate for the estimation of said drug. The proposed developed HPTLC method can be applied for identification and quantitative determination of imatinib mesylate in bulk drug and dosage forms.     

Antioxidant Potential of Gynura procumbens

Abstract

The leaves of Gynura procumbens (Merr.) Compositae, commonly called “sambung nyawa” in Malaysia, are often eaten raw with rice. The methanol extract was prepared from the dried leaves using a Soxhlet apparatus. The methanol extract was then fractionated into chloroform, ethyl acetate, n-butanol, and aqueous fractions using a separating funnel. In the current study, the antioxidant potency of G. procumbens extract and fractions were investigated, employing various established in vitro systems, such as trolox equivalent antioxidant capacity, β -carotene–linoleic acid model system, 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging, reducing power, and xanthine oxidase inhibitory activity. Based on the results obtained, the extract and fractions showed different antioxidant potential. Among the fractions, the ethyl acetate fraction displayed higher antioxidant properties. The contents of the potential antioxidant component of the extract and fractions were also determined using HPTLC densitometric and spectrophotometric (using Folin-Ciocalteu reagent) methods. HPTLC study revealed that the methanol extract and the ethyl acetate and n-butanol fractions contain 0.74% and 2.9%, 7.76% and 12.75%, and 4.52% and 0.33% of kaempferol-3-O-rutinoside and astragalin, respectively. The total phenolic content of the extract and fractions varied from 4.37% to 23.43% of dry weight, expressed as gallic acid equivalents (GAE). With further data analysis, it was found there was a significant correlation (p < 0.05) between the total phenolic content of the sample and its DPPH scavenging activity and reducing power with correlation coefficients (r) of 0.891 and 0.926, respectively. These results suggest that phenolics in these plants provide substantial antioxidant activity.     

Genetic and metabolic diversity in Stevia rebaudiana using RAPD and HPTLC analysis

Abstract

Context: Stevia rebaudiana Bertoni (Asteraceae) is an important medicinal plant and is much used due to its zero calories sweetening property. Stevia leaves as well as its extracts and pure compounds are currently used in the preparation of several medicines, food products and neutraceuticals.

Objective: To study the genetic and metabolic variability in S. rebaudiana among accessions of different geographical regions of India using random amplified polymorphic DNA (RAPD) markers and high-performance thin layer chromatography (HPTLC) analysis.

Materials and methods: The RAPD analysis of Stevia rebaudiana (11 accessions) was carried out using 20 random operon primers. Dendrogram was constructed for cluster analysis based on the unweighted pair group method with arithmetic means (UPGMA) using Winboot. The HPTLC analysis of all samples was carried out on silica using acetone:ethyl acetate:water (5:4:1, v/v/v) for fingerprinting and quantification of stevioside and rebaudioside A at 360?nm after spraying with anisaldehyde sulphuric acid.

Results: Ten out of 20 primers screened were found most informative; amplification products of the genotypes yielded a total of 87 scorable bands (67 polymorphic), whereas genetic similarity (GS) coefficient (0.01–0.08) and polymorphism (67.24–92.40%) showed huge variability. Similarly, HPTLC analysis showed large variation among different samples with respect to their presence or absence of metabolite and their concentration.

Conclusion: Out of the 11 Stevia accessions, Delhi and Mohali varieties showed much relatedness with each other and were concluded to be the superior genotype in context to RAPD and HPTLC analysis. The information obtained here could be valuable for devising strategies for cultivating this medicinal plant.     

Effect of macronutrient deficiency on withanolides content in the roots of Withania somnifera and its correlationship with molybdenum content

Abstract

Context: The content of withanolides in the roots of Withania somnifera (L.) Dunal (Solanaceae) is important for therapeutic application. Earlier studies have shown that the deficiency of macro- and micronutrients affects the growth of W. somnifera. Therefore, we examined the effect of these deficiencies on the withanolides content of the roots.

Objective: To examine the effect of molybdenum accretion in nitrogen-, phosphorus-, calcium- and potassium-deficient soils on the accumulation of withanolides in the roots of W. somnifera. Different withanolides have different therapeutic applications hence major bioactive withanolides assume importance.

Materials and methods: Methanol extracts of the roots were subjected to HPTLC and individual withanolides were identified by comparing their R_f values with those of the authentic samples. Molybdenum was quantified by atomic absorption spectroscopy. Free radical scavenging activity was monitored by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay.

Results: Molybdenum content in roots of nitrogen-, phosphorus-, calcium-, potassium-deficient, and control plants were 7.02?±?2.1, 13.1?±?1.6, 17.1?±?0.9, 33.5?±?3.3, and 33.9?±?1.6?ppm, respectively. Levels of withaferine A increased with the increase in the Mo content in roots from 7.79?±?2.2?mg/g to 12.57?±?3.4?mg/g. Antioxidant activity of nitrogen-deficient plants was the lowest (24.7?±?2.2%) compared to other groups.

Discussion and conclusion: It was observed that nitrogen metabolism-dependent molybdenum uptake influences the withanolides accumulation in the roots.     

A rapid,sensitive, and greener stability-indicating normal-phase HPTLC method with univariate calibration for the estimation of chlorhexidine acetate in its commercial formulations

Till date, there is no report on high-performance thin-layer chromatography (HPTLC) analysis of chlorhexidine (CHD) or its salts like CHD acetate (CHD-A), CHD gluconate, and CHD hydrochloride. Therefore, a rapid, sensitive, and greener normal-phase HPTLC method has been reported for the analysis of CHD-A in its four different commercial dosage forms. The quaternary combination of ethyl acetate: ethanol: water: formic acid (75:10:10:5, v v v v^?1) was optimized as the green solvent system/mobile phase for CHD-A analysis. The CHD-A detection was carried out at 264 nm. The greener normal-phase HPTLC assay was linear in the range of 10–2000 ng band^?1. In addition, the proposed method was accurate, precise, sensitive, and selective for CHD-A analysis. The greener normal-phase HPTLC method was able to detect CHD-A in the presence of its degradation products, suggesting the stability-indicating property of this method. The content of CHD-A in commercial products A, B, C, and D was detected as 0.18, 2.02, 1.46, and 0.19% w w^?1, respectively. The greenness scale for the greener normal-phase HPTLC assay was estimated as 0.88 utilizing “analytical GREEnness (AGREE)” calculator, suggested the greener nature of the normal-phase HPTLC assay. Overall, these data suggested that the greener normal-phase HPTLC method can be successfully used for the determination of CHD-A in its commercial products.     

Development and Validation of a HPTLC Method for the Estimation of Sumatriptan in Tablet Dosage Forms

A simple, precise, accurate and rapid high performance thin layer chromatographic method has been developed and validated for the estimation of sumatriptan in tablet dosage forms. The stationary phase used was precoated silica gel 60F254. The mobile phase used was a mixture of methanol:water:glacial acetic acid (4.0:8.0:0.1, v/v/v). The detection of spots was carried out at 230 nm. The method was validated in terms of linearity, accuracy, precision and specificity. The calibration curve was found to be linear between 200 to 800 ng/spot. The limit of detection and the limit of quantification for the sumatriptan were found to be 63.87 and 193.54 ng/spot, respectively. The proposed method can be successfully used to determine the drug content of marketed formulation.     

Fingerprinting of Plumbagin in lic>Drosera burmannii Vahl using High Performance Thin Layer Chromatography

HPTLC fingerprinting profile of the alcohol and aqueous extracts of Drosera burmannii is described. Seven components have been detected in the alcohol extract. Further, plumbagin, an useful antifertility agent, was also detected by comparison with the reference standard. The aqueous extract revealed two spots with no spot corresponding to plumbagin.