ABSTRACT. DNA barcoding is a desirable tool for medicinal product authentication. DNA barcoding is a method for species identification using short DNA sequences that are conserved within species, but variable between species. Unlike animals, there is no single universal DNA barcode locus for plants. Coding markers, matK and rbcL, and noncoding markers, trnH-psbA (chloroplast) and ITS2 (nuclear), have been reported to be suitable for the DNA barcoding of plants with varying degree of success. Sixty-four accessions from 20 species of the medicinal plant Cassia were collected, and analyzed for these 4 DNA barcoding markers. PCR amplification was 100% successful for all 4 markers, while intra-species divergence was 0 for all 4 Cassia species in which multiple accessions were studied. Assuming 1.0% divergence as the minimum requirement for discriminating 2 species, the 4 markers could only differentiate 15 to 65% of the species studied when used separately. Adding indels to the divergence increased the percentage of species discrimination by trnH-psbA to 90%. In 2-locus barcoding, while matK+rbcL (which is recommended by Consortium for the Barcoding of Life) discriminated 90% of the species, the other combinations of matK+ITS and rbcL+trnH-psbA showed 100% species discrimination. However, matK is plagued with primer issues. The combination of rbcL+trnH-psbA provided the most accurate (100% species ID) and efficient tiered DNA barcoding tool for the authentication of Cassia medicinal products.

Objective: Bacterial infections and the resistance related to indiscriminate antibiotic use have led to an alarming situation in the clinics. The rapid spread of Extended Spectrum Beta Lactamases (ESBLs) and carbapenemase producing Gram negative bacteria has initiated the need for development of a new drug or an alternative choice by using the combination of drugs with medicinal plant extracts. This study was aimed at examining the antibacterial potential and synergistic activity of ethanolic extracts of Terminalia chebula and Terminalia bellerica fruits against clinically important reference bacterial strains.Methods: The crude ethanolic extracts of T. chebula and T. bellerica fruits were prepared and reconstituted with 5% dimethylsulfoxide (DMSO). The fruit extracts (~25 mg/well) were added into the wells in the plates inoculated with various ESBL and AmpC producers and they were incubated at 37 °C for 24 h. The antibiotics ceftazidime (30 µg) and cefotaxime (30 µg) were added to the wells alone and in combination with the fruit extracts to determine their own antibacterial and synergistic activity respectively.Results: The ethanolic fruit extracts combination improved the activity of ceftazidime and cefotaxime against the tested ESBL and AmpC producers. Though both the extracts showed activity, T. chebula was found to show better synergistic antibacterial activity.Conclusion: The synergistic activity of these fruit extracts with ceftazidime and cefotaxime against the ESBL and AmpC producers shows the efficiency of the combination therapy, which can be considered in therapeutic point of view to prevent the misuse of antibiotics and minimise the increasing resistance in bacteria.

No abstract