Green synthesis of silver nanoparticles using aqueous rhizome extract of Zingiber officinale and Curcuma longa: In-vitro anti-cancer potential on human colon carcinoma HT-29 cells.

This study was aimed to analyze the anti-cancer activity of silver nanoparticles (AgNPs) synthesized using aqueous plant extracts from the rhizome of Curcuma longa and Zingiber officinale. Synergistic aqueous extract of rhizome of C. longa and Z. officinale was used to green synthesis of AgNPs. Characterization of AgNPs was performed using UV-visible spectroscopy, FTIR, X-ray diffraction, TEM, and SEM analyses. Anti-cancer activity of AgNPs against human colon carcinoma (HT-29) cells was tested using MTT assay. UV-Visible spectroscopy analysis indicated the surface plasmon resonance (SPR) sharp peak at 350-430 nm wavelength that corresponds to the production of AgNPs. FTIR analysis reveals that existence of carboxyl (-C[bond, double bond]O) and amine (N-H) functional groups in the AgNPs. The X-ray diffraction analysis confirms four spectral peaks at 111, 200, 220, and 311. SEM analysis showed that AgNPs are in a spherical shape with a size of 42-61 nm and TEM analysis showed particle size are ranged between 20-51 nm. Anti-cancer study reveals that AgNPs had shown cytotoxicity against HT-29 cells at the concentrations ranged from 25 to 500 µg/mL and IC50 at 150.8 µg/mL. This study concludes that AgNPs synthesized using rhizome of Z. officinale and C. longa possesses potential anti-cancer activity.

In vitro Antibacterial Activity of Aqueous and Ethanol Extracts of Aristolochia indica and Toddalia asiatica Against Multidrug-Resistant Bacteria.

Bacteria have developed multidrug resistance against available antimicrobial agents. Infectious diseases caused by these multidrug-resistant bacteria are major causes of morbidity and mortality in human beings. Synthetic drugs are expensive and inadequate for the treatment of diseases, causing side effects and ineffective against multidrug-resistant bacteria. The medicinal plants are promising to have effective antimicrobial property due to presence of phytochemical compounds like alkaloids, flavanoids, tannins and phenolic compounds. The present study aimed to find the antimicrobial activity of medicinal plants against multidrug-resistant bacteria. Multidrug-resistant bacteria were identified by Kirby-Bauer disc diffusion method. Production of ß-lactamases (extended spectrum ß-lactamases, metallo ß-lactamase and AmpC ß-lactamase) were identified by combination disc method. Antibacterial activity of aqueous and ethanol extract of Aristolochia indica and Toddalia asiatica were detected by agar well diffusion assay and minimum inhibitory concentration. All bacteria used in this study showed antibiotic resistance to ≥3 antibiotics. Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Proteus mirabilis and Vibrio cholerae were found to be positive for ß-lactamase production. Ethanol extract of Aristolochia indica showed more significant antibacterial activity against multidrug-resistant bacteria than Toddalia asiatica. Ethanol extracts of Aristolochia indica and Toddalia asiatica showed minimum inhibitory concentration values of 50-100 µg/ml and 100-200 µg/ml, respectively against multidrug-resistant bacteria. From this study, it was concluded that Aristolochia indica has more potential to treat multidrug-resistant bacteria than Toddalia asiatica.