Ethnopharmacology, phytochemistry, and biotechnological advances of family Apocynaceae: A review.

The family Apocynaceae is one of the largest and important families in angiosperm. Several members of this family have medicinal properties and have been in the treatment of various ailments. Most of them are consumed as food by tribal people whereas a few plants are used as source of poison. Members of family Apocynaceae are rich in alkaloids, terpenoids, steroids, flavonoids, glycosides, simple phenols, lactones, and hydrocarbons. Other compounds such as sterols, lignans, sugars, lignans, and lactones have been isolated and systematically studied. Few studies have reported antioxidant, anti-inflammatory, antimicrobial, and cytotoxic activities of crude extracts as well as single compound(s) isolated from various members of the family Apocynaceae. Holarrhena antidysenterica, Rauvolfia serpentina, Carissa carandas, and Tabernaemontana divaricata are the extensively studied plants in this family. The present review provides a detailed outlook on ethnopharmacology, phytochemistry, and biological activities of selected members of this family. Moreover, it also covers the biotechnological advances used for large-scale production of bioactive compounds of therapeutic interest along with plant tissue culture-based approaches for conservation of this medicinally valuable family.

Antidiarrheal activity, chemical and toxicity profile of Berberis aristata.

CONTEXT: This study evaluated the in vitro and in vivo antidiarrheal activity, oral acute toxicological profile, and developed a chemical fingerprint of Berberis aristata Linn. (Berberidaceae). MATERIALS AND METHODS: The ethanol (by maceration) and aqueous (by Soxhlet) extracts of Berberis aristata bark were used for the study. The study involved the antimicrobial (minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) by micro dilution) and antidiarrheal (castor oil induced diarrhea, charcoal motility) tests. The active principle, berberine was characterized by different spectroscopic and chromatographic techniques. RESULTS: The MIC and MBC (of both extracts) against all strains of Shigella were recorded between 125 to 500 µg/mL and 300 to 600 µg/mL, respectively. The MIC and MBC values of berberine are almost comparable to standard ciprofloxacin. UV and IR spectroscopy along with HPTLC and HPLC studies showed presence of berberine in the extracts. The onset of castor oil induced diarrhea was delayed and number of diarrheal episodes was reduced by both the extracts in a dose dependent manner. Similarly, the length of intestine traveled by the feed was also significantly reduced in the charcoal motility test by both the extracts. LD(50) of >5000 mg/kg body weight was observed for both extracts in the acute oral toxicity studies with Swiss albino mice. CONCLUSION: The results validate in vivo and in vitro antidiarrheal activity of Berberis aristata extracts and provide its chemical fingerprint.

A glycoprotein α-amylase inhibitor from Withania somnifera differentially inhibits various α-amylases and affects the growth and development of Tribolium castaneum.

BACKGROUND: Identification and characterisation of plant defensive molecules enrich our resources to design crop protection strategies. In particular, plant-derived proteinaceous inhibitor(s) of insect digestive enzymes appear to be a safe, sustainable and attractive option. RESULTS: A glycoprotein having non-competitive α-amylase inhibitory activity with a molecular weight of 8.3 kDa was isolated and purified from seeds of Withania somnifera α-amylase inhibitor (WSAI). Its mass spectrometry analysis revealed 59% sequence coverage with Wrightide II-type α-amylase inhibitor from Wrightia religiosa. A dose-dependent inhibition of α-amylases from Aspergillus oryzae, Bacillus subtilis, Helicoverpa armigera and Tribolium castaneum was recorded. Interestingly, WSAI did not inhibit human salivary α-amylase significantly. When adults of T. castaneum were fed with WSAI (1.6 mg g-1 ), decrease in consumption, growth and efficiency of conversion of ingested food was evident, along with over fourfold increases in feeding deterrence index. A decline in larval residual α-amylase activity after feeding of WSAI resulted in a reduction in longevity of T. castaneum. CONCLUSION: The study reflects the significance of WSAI in affecting the overall growth and development of T. castaneum. Pre- and post-harvest pest resistive capability makes WSAI a potential candidate for insect pest management. Further, the effectiveness of this inhibitor could be explored either in formulations or through a transgenic approach. © 2016 Society of Chemical Industry.

Partial characterization and insecticidal properties of Ricinus communis L foliage flavonoids.

Aqueous leaf extract of Ricinus communis L (Euphorbiaceae), a cultivated plant in tropical countries, showed excellent insecticidal activity against Callosobruchus chinensis L (Coleoptera: Bruchidae). We have isolated and tested flavonoids as insecticidal and antimicrobial agents. The isolated flavonoids showed potential insecticidal, ovicidal and oviposition deterrent activities against C chinensis L. However, antimicrobial activity against the common microbial infestants of stored pulses, of which C chinensis is a major pest, was found to be insignificant. Two bands having Rf 0.63 and 0.69 were seen on HPTLC plates using mobile phase benzene + ethyl acetate + methanol + formic acid (12 + 4.5 + 2 + 1.5 by volume) as eluant. The Rf values and scanning of the spectrum in the ultraviolet region, showed identity with the flavonoids quercetin and kaempferol. This was further confirmed using HPLC and IR and UV spectrometry. HPLC and HPTLC chromatograms also suggested quercetin to be the major flavonoid present in the hydrolyzed aqueous leaf extract of R communis.

Antimicrobial and pesticidal activity of partially purified flavonoids of Annona squamosa.

Foliar extracts of Annona squamosa (Family: Annonaceae) were screened for antimicrobial and insecticidal activity against the common microbial infestants of pulses and the stored grain pest pulse beetle, Callosobruchus chinensis (Coleoptera: Bruchidae). Flavonoids isolated from aqueous extracts of A squamosa showed antimicrobial activity against all the common microbial contaminants of pulses and 80% insecticidal activity against C chinensis at a concentration of 0.07 mg ml-1. Various physico-chemical tests, chromatographic and spectroscopic studies with partially purified aqueous extract indicated the presence of flavonol type flavonoids. This may provide a useful beginning for the development of botanical pesticides for post-harvest safeguard of pulses.

Production of lovastatin by wild strains of Aspergillus terreus.

A wild fungal strain of Aspergillus terreus, labeled as PM3, was isolated by using the Candida albicans bioassay and confirmed by 18S r DNA analyses. Lovastatin was produced by submerged and solid state fermentations. Of the 30 isolated fungal strains, 11 showed lovastatin production with Aspergillus terreus PM3 being the best with a yield of 240 mg/L at the 10th day of submerged fermentation. Carboxymethylcellulose had a stimulatory effect on lovastatin production. It restricted uncontrolled filamentous growth, induced pellet formation and, thereby, improved lovastatin yield. In solid state fermentation (SSF), of the agro wastes from five crops (bran of wheat and rice, husks of red gram and soybean, and green gram straw), wheat bran showed maximum lovastatin production (12.5 mg/g of dry substrate) at pH 7.1 and a temperature of 30 +/- 2 degrees C. Development of a lovastatin production process based on wheat bran as a substrate in SSF is economically attractive as it is a cheap and readily available raw material in agriculture-based countries.