Deepak Kumar Semwal

Anti-hyperglycemic effect of 11-hydroxypalmatine, a palmatine derivative from Stephania glabra tubers.

A palmatine derivative, named 11-hydroxypalmatine (4), has been isolated from the tubers of Stephania glabra, together with three known alkaloids, palmatine (1), dehydrocorydalmine (2), and stepharanine (3). The structures of the compounds were elucidated by means of spectroscopic analysis including 2D NMR experiments. The hypoglycemic activity of 4 was evaluated against alloxan-induced diabetic mice. The test compound was administered at doses of 25, 50, and 100 mg/kg, p.o., 36 h after alloxan injection (60 mg/kg, i.v.). The alloxan-induced diabetic mice showed significant reduction in blood glucose after treatment with the test compound by 52% as compared to the positive control glibenclamide (54%) and the diabetic control (27%).

Chemical constituents from the leaves of Boehmeria rugulosa with antidiabetic and antimicrobial activities.

Three new flavonoid glycosides, named chalcone-6′-hydroxy-2′,3,4-trimethoxy-4′-O-β-d-glucopyranoside (1), isoflavone-3′,4′,5,6-tetrahydroxy-7-O-{β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside} (2), and isoflavone-3′,4′,5,6-tetrahydroxy-7-O-{β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl-(1 → 6)-β-d-glucopyranosyl-(1 → 3)-α-l-rhamnopyranoside} (3), were isolated from the leaves of Boehmeria rugulosa, together with five known compounds, β-sitosterol, quercetin, 3,4-dimethoxy-ω-(2′-piperidyl)-acetophenone (4), boehmeriasin A (5), and quercetin-7-O-β-d-glucopyranoside. The structures of the isolated compounds were determined by means of chemical and spectral data including 2D NMR experiments. The ethanolic extract of leaves showed significant hypoglycemic activity on alloxan-induced diabetic mice. Glibenclamide, an oral hypoglycemic agent (5 mg/kg, p.o.), was used as a positive control. The ethanolic extract of the plant as well as the isolated compounds 1–3 (25 μg/ml) showed potent antimicrobial activity against two bacterial species (Staphylococcus aureus and Streptococcus mutans) and three fungus pathogens (Microsporum gypseum, Microsporum canis, and Trichophyton rubrum). The activities of the isolated compounds 1–3 have been compared with positive controls, novobiocin, and erythromycin (15 μg/ml).

Antimicrobial hasubanalactam alkaloid from Stephania glabra.

A novel hasubanalactam alkaloid, named glabradine, has been isolated from the tubers of Stephania glabra, together with three known quaternary protoberberine alkaloids, palmatine, dehydrocorydalmine and stepharanine. The structure of glabradine was assigned as 7-O-demethyl-N,O-dimethyloxostephinine, by means of rigorous spectroscopic analysis including 2 D NMR measurements. It was evaluated for antimicrobial activity against Staphylococcus aureus, S. mutans, Microsporum gypseum, M. canis and Trichophyton rubrum and displayed potent antimicrobial activity superior to those of novobiocin and erythromycin used as positive controls.

Efficacy and safety of Stephania glabra: an alkaloid-rich traditional medicinal plant

Stephania glabra (Roxb.) Miers (Menispermaceae) has long been used for the treatment of asthma, tuberculosis, dysentery, hyperglycaemia, cancer, fever, intestinal complaints, sleep disturbances and inflammation in many Asian countries. It mainly contains alkaloids and, until now, over 30 alkaloids such as bisbenzylisoquinolines, hasubanalactams, berberines and aporphines have been isolated from its tuber. Most of its traditional medicinal activities are scientifically approved by various in vitro and in vivo studies. It shows remarkable anti-psychotic, anti-diabetic, antipyretic, analgesic, antimicrobial and anti-hypertensive activities. This work includes comprehensive information on the ethnobotany, chemistry and pharmacology of S. glabra. This review also focuses on the future perspectives with main emphasis on the establishment of therapeutic index and safety index of the plant. This review concludes that S. glabra has a great potential to treat various diseases, and could be used as a source for novel healthcare products in the near future, which needs further studies.

Celtisanin, a novel sulphonated phenolic from Celtis australis L. fruits

A novel sulphonated phenolic named celtisanin (1), elucidated as 3-[8′-hydroxy-prop-6′-ene-6′-yl]-5-hydroxymethyl-4-methoxy-2-[penta-1′,4′-diene-1′-yl-5′-sulphonic acid]-5,6-dihydrobenzofuran, has been isolated from the fruits of Celtis australis (Ulmaceae), together with three known compounds: apigenin, quercetin and its glucoside. Their structures were characterised by means of chemical and spectral methods, including advanced 2-D nuclear magnetic resonance (NMR) studies.

A New Triterpenoid Saponin and Antimicrobial Activity of Ethanolic Extract from Sapindus mukorossi Gaertn.

A new acetylated triterpenoid saponin elucidated as hederagenin-3-O-β-D-xylopyranosyl (2→1)-[3-O-acetyl-α-L-arabinopyranosyl-28-O-α-L-rhamnopyranosylester has been isolated from pericarps of Sapindus mukorossi Gaertn. The structure of the compound was determined by means of chemical and spectral analysis including advanced 2D NMR studies. The ethanolic extract from pericarps of the plant showed significant in vitro antimicrobial activity against various test organisms by Agar well diffusion method.

Chemical Constituents and Biological Significance of the Genus Ilex (Aquifoliaceae)

The genus Ilex (Aquifoliaceae) was reviewed for its chemical constituents and pharmacological significance including traditional uses. The structure-activity relationship for various compounds was illustrated to understand the mechanism of a particular activity. The genus has been known for its numerous biological activities like antioxidant, antimicrobial, cytotoxic, anti-platelet aggregation, anti-inflammatory etc. Most of the plants of this genus are rich sources of triterpenoids and saponins. Besides, these plants also contain flavonoids, alkaloids, anthocyanins and other phenolics in minute quantity. The bioactive constituents or plants extracts themselves, in the form of herbal drugs from this genus, have been validated for the treatment of various diseases and these would be used as a new formulation for the novel drugs discovery in pharmaceutical industries.

Ayurvedic research and methodology: Present status and future strategies.

Ayurveda is a science of life with a holistic approach to health and personalized medicine. It is one of the oldest medical systems, which comprises thousands of medical concepts and hypothesis. Interestingly, Ayurveda has ability to treat many chronic diseases such as cancer, diabetes, arthritis, and asthma, which are untreatable in modern medicine. Unfortunately, due to lack of scientific validation in various concepts, this precious gift from our ancestors is trailing. Hence, evidence-based research is highly needed for global recognition and acceptance of Ayurveda, which needs further advancements in the research methodology. The present review highlights various fields of research including literary, fundamental, drug, pharmaceutical, and clinical research in Ayurveda. The review further focuses to improve the research methodology for Ayurveda with main emphasis on the fundamental research. This attempt will certainly encourage young researchers to work on various areas of research for the development and promotion of Ayurveda.

Ethnobotany, Pharmacology and Phytochemistry of the Genus Phoebe (Lauraceae)

The research on medicinal plants is gaining popularity due to their high efficacy, safety, quality and low side effects in comparison of synthetic medicines. Phoebe plants have been used in traditional medicine for curing various dis- eases worldwide. The Genus Phoebe comprises of about 200 species, distributed in Indo-Malaysia, West Europe, Tropical America and India. The phytochemical studies on the Genus Phoebe have revealed the presence of mostly alkaloids along with terpenoids, flavonoids, lignans and steroids. The members of this genus showed various activities such as antitumor, antiplasmodial, antimicrobial, antifungal, antidiabetic, muscles relaxant etc. The aim of present review is to explore the up to date knowledge concerning ethnobotany, pharmacology and phytochemistry of the Genus Phoebe.

Further Aporphine Alkaloids from Phoebe lanceolata

Stem bark of Phoebe lanceolata was extracted with ethanol and fractionated with ethyl acetate yielded soluble and insoluble fractions. Ethyl acetate insoluble fraction was subjected to column chromatography afforded two oxalyl-fused didehydroaporphine alkaloids, N-6/C-7 oxalyl-fused 2,9-dihydroxy-1,10-dimethoxy 6a,7-didehydroaporphine and N-6/C-7 oxalyl-fused 1,2,9,10-tetramethoxy 6a,7-didehydroaporphine along with well known β-sitosterol and β-sitosterol glucoside. The structures of isolated compounds were elucidated by chemical and spectral analysis.