Asparagus racemosus Willd. is widely used to combat various diseases owing to its medicinal properties. In this study, arial parts of A. racemosus were investigated for their total phenolic content, total flavonoid content and antioxidative potential. A high-performance thin-layer chromatography (HPTLC) method combined with effect-directed-analysis was also developed to screen the antioxidant effects of A. racemosus and quantify biologically active compounds on chromatograms from A. racemosus. Total phenolics (154 mg gallic acid equivalent/g), flavonoid contents (497 mg quercetin/g) and IC 50 (15.25 μg/ml) were found to be higher in methanolic extract of A. racemosus than in n-hexane, chloroform and ethyl acetate extracts.HPTLC hyphenated with chemical derivatizations (DPPH•, p-anisaldehyde/sulfuric acid, and ferric chloride) was used to evaluate antioxidant activity and the presence of phytosterols, terpenoids and polyphenolic contents. The same compounds at 100*retention factor = 58, 68, 74 and 65 in extracts were responsible for antioxidant activity. Hyphenated HPTLC allowed a rapid characterization of the active compound with a combination of effect-directed-analysis and attenuated total reflectance-Fourier transform infrared spectroscopy. Spectral analysis of the band from attenuated total reflectance identified myricetin, quercetin, p-coumaric acid and caffeic acid as responsible for the antioxidant activity.

Different parts of Camellia sinensis (L.) were extracted with solvents according to polarity, and the extracts’ phytochemical profiling and biological activities were examined. The total phenolic (TPC) and total flavonoid (TFC) contents increased with the increasing polarity of the solvent which met its maximum in polar solvents. The increasing antioxidant, anti-inflammatory and antidiabetic activities were recorded with increasing polarity of solvents which showed hydroalcoholic as best solvent. The strong and significant correlation was among the TPC, TFC, DPPH, anti-inflammatory and antidiabetic activities for different parts of tea. HPTLC study of individual phenolic acids, epigallocatechin gallate, gallocatechin and theaflavin met their maximum level of content with polar solvents like hydroalcohol, methanol and water mostly in mainly tea leaves. Our finding suggested that the polar solvents and young leaves of tea were beneficial for obtaining extracts. On the other hand, phenolics were found to be potent antioxidant, anti-inflammatory and antidiabetic agent.

Tea is the most popular daily drink consumed globally, with a high concentration of caffeine and polyphenols. In this study, the effects of ultrasonic‐assisted extraction and quantification of caffeine and polyphenols from green tea were investigated and optimized using 23‐full factorial design and high‐performance thin‐layer chromatography. Three parameters were optimized to maximize the concentration of caffeine and polyphenols extracted using ultrasound: crude drug‐to‐solvent ratio (1:10–1:5), temperature (20–40°C), and ultrasonication time (10–30 min). The optimal conditions achieved from the model for tea extraction were as follows: crude drug‐to‐solvent ratio, 0.199 g/ml; temperature, 39.9°C; and time, 29.9 min; the extractive value was found to be 16.8%. Images from scanning electron microscopy showed that the matrix underwent a physical alteration and cell wall disintegration, which intensified and accelerated the extraction. This process might be simplified using sonication, which results in a higher extractive yield and a significant concentration of caffeine and polyphenols than the traditional approach, with a smaller quantity of solvent and faster analytical times. The result of high‐performance thin‐layer chromatography analysis proves a significant positive correlation between extractive value and caffeine and polyphenol concentrations.

Introduction: α-Amylase inhibitors from natural sources are of interest for new drug development for the treatment of diabetes mellitus (DM). High-performance thinlayer chromatography (HPTLC) coupled bioassay guided isolation of bioactive compounds has been improved within last few years.Objective: A microchemical derivatised HPTLC-coupled attenuated total reflectance-Fourier-transform infrared (ATR-FTIR) and nuclear magnetic resonance (NMR) spectroscopy was employed for profiling α-amylase inhibitor from the aerial part of Asparagus racemosus Willd.Methodology: Asparagus racemosus Willd. aerial part extracted with different solvents (n-hexane, chloroform, ethyl acetate, and methanol) and assayed to detect free radical scavengers and α-amylase inhibitor by 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and starch-iodine assay method, respectively. HPTLC-coupled ATR-FTIR and NMR spectroscopy was used to identify the α-amylase inhibitor.Results: Methanolic extract of A. racemosus showed highest antioxidant activity (21.99 μg GAE/μL) where n-hexane extract showed lowest antioxidant activity (5.87 μg GAE/μL). The α-amylase inhibition was recorded as highest and lowest in ethyl acetate extract (13.13 AE/μL) and n-hexane extract (3.92 AE/μL), respectively.The deep blue zone of α-amylase sprayed TLC plate of extracts with hR F = 72 analysed for ATR-FTIR and NMR spectroscopy which revealed the presence of stigmasterol is responsible for α-amylase inhibition. Conclusion:The present work establishes the α-amylase inhibiting properties of A. racemosus maintaining its use for the treatment of DM as a traditional medicine.Bioassay guided isolation through HPTLC-coupled ATR-FTIR and NMR spectroscopy offers an effective method for the exploration of bioactive compounds such as α-amylase inhibitor from complex plant extracts.