Search Results

You are looking at 1 - 4 of 4 items for

  • Author or Editor: Aziz Ahmed x
Clear All Modify Search

Eight compounds were isolated and identified from the soil-inhabiting fungus Aspergillus fumigatus 3T-EGY, namely, stearic acid (1), α-linolenic acid (2), physcion (3), di-(2-ethylhexyl) phthalate (4), 2,4,5,17-tetramethoxy pradimicin lactone (5), 3,5-dihydroxy-7-O-α-rhamnopyranoyl-2H-chromen-2-one (6), juglanthraquinone A-5-O-d-rhodosamine-(4′→1″)-2-deoxy-d-glucose (4″→1″′)-cinerulose B (7), and micropeptin (8). Their structures were determined on the basis of one-dimensional (1D-) and two-dimensional nuclear magnetic resonance (2D-NMR) [1H-, 13C-NMR, 1H-1H COSY (COrrelated SpectroscopY), and 1H-13C HMBC (Heteronuclear Multiple Bond Correlation) spectroscopy]. Compound 7 showed moderate in vitro antimicrobial activity against three pathogenic strains with inhibition zones values were ranged from 9.0 to 10.66 mm compared to neomycin as a positive control with inhibition zones values were ranged from 14.0 to 19.0 mm.

Open access

Context

Bacoside A, a triterpenoid saponin, is a major constituent isolated from Bacopa monnieri (L.) Wettst. (Scrophulariaceae), used as a memory enhancer. Bacoside A and B are active ingredients in Bacopa herb and have antioxidant and hepatoprotective activities

Objective

A new rapid, simple, and economical high-performance thin-layer chromatographic (HPTLC) method was developed and validated for densitometric quantitative analysis of bacoside A in powdered leaves from different geographical regions of India.

Materials and methods

An amount of 10 mg mL−1 methanol extract of powdered leaves from different geographic regions was used for sample application on precoated silica gel 60 F254 aluminum sheets. Standard bacoside A (1 mg mL−1) was used for calibration curve. HPTLC separation was performed on percolated silica gel aluminum plate 60 F254 (20 cm × 10 cm with 0.2 mm thickness) as a stationary phase using ethyl acetate–methanol–water (4:1:1) as the mobile phase. Quantification was achieved by densitometric analysis at 598 nm over the concentration range of 500–4000 ng band−1.

Result

Compact and well-resolved bands for bacoside A from powdered leaves of different geographic regions were found at retardation factor (R f) 0.53 ± 0.02. The linear regression analysis data for calibration curve showed good linear relationship with regression coefficient r 2 = 0.9996 and r 2 = 0.99810 with respect to peak area and peak height. The method was validated for precision, recovery, and robustness as per the International Conference on Harmonization (ICH) guidelines. Variation in quantitative analysis of bacoside A in powdered leaves sample from different geographic regions was found by HPTLC method.

Discussion and conclusion

The highest and lowest content of bacoside A in powdered leaves sample from Jammu and Kerala regions, respectively. The variety of B. monnieri in Jammu is superior to other regions of India. The proposed developed HPTLC method can be applied for the quantitative determination of bacoside A in powdered leaves of plant and its formulation.

Restricted access
JPC - Journal of Planar Chromatography - Modern TLC
Authors: Mohamed Abdel Tawab Korany, Marwa Said Moneeb, Dina Ahmed Selim, Aya Mohamed Asaad and Nadia Abdel Aziz El-Sebakhy
Restricted access
Acta Chromatographica
Authors: Omar M. Khalaf, Mosad A. Ghareeb, Amal M. Saad, Hassan M. F. Madkour, Ahmed K. El-Ziaty and Mohamed S. Abdel-Aziz

Different solvent extracts of the aerial parts of Senna italica (Mill.) were investigated for their chemical constituents and biological activities. Moreover, bio-guided fractionation led to isolation and identification of six compounds, namely: physcion (1), emodin (2), 2-methoxy-emodin-6-O-β-d-glucopyranoside (3), 1-hydroxy-2-acetyl-3-methyl-6-hydroxy-8-methoxynaphthalene (tinnevellin) (4), quercetin 3-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (rutin) (5), and 1,6,8-trihydroxy-3-methoxy-9,10-dioxo-9,10-dihydroanthracene (6). The chemical structures of these compounds were established via 1D and 2D 1H- and 13C-NMR spectroscopy. Ethyl acetate and n-butanol extracts as well as compound 3 were evaluated for their anticancer activity against tumor cell lines. The tested extracts showed a moderate to weak activity, while compound 3 showed a moderate activity against human liver cancer (Hep G2) and breast cancer (MCF-7) cell lines with IC50 values of 57.5 and 42.3 μg/mL, respectively. Both ethyl acetate and n-butanol extracts exhibited antimicrobial activities with different strengths, i.e., ethyl acetate exhibited antimicrobial activity against seven test microbes while n-butanol extract showed antimicrobial activity against all tested microbes. This is the first report for the isolation of compound 3 as a new compound from S. italica growing in Egypt.

Open access