In Vitro Hepatoprotective Activity of Isolated Fractions of Cressa Cretica

Phytochemical and Cytotoxicity Studies of Callistemon viminalis Leaves Extract Growing in Egypt

OBJECTIVE

To isolate and identify new compounds from the methanolic extract of Callistemon viminalis leaves collected in Cairo, Egypt and evaluate its cytotoxic and hepatoprotective potentials.

METHODS

The methanolic extract of Callistemon viminalis leaves was fractionated and subjected to different chromatographic techniques to isolate pure, new compounds which were identified by nuclear magnetic resonance (NMR), spectroscopic analysis and mass spectrometric methods. The methanolic extract of the leaves was assessed for its cytotoxic and hepatoprotective activities against Hepatocellular carcinoma cells (Hep G-2 cell line) by estimating the viability of the HepG2 cells by the MTT reduction assay.

RESULTS

Six compounds were isolated and identified for the first time from the methanolic extract of Callistemon viminalis leaves, three compounds are new flavonoids namely; 3-O-[α-L-arabinopyranosyl- (1→2)-α-L-arabinopyranosyl)]-3'-O-methylquercetin (C1); 5,7,3',4' tetrahydroxy isoflavone-7-O-α- L-1C4- rhamnopyranosyl (1'''-6'')-O-β-D-4C1-glucopyranoside (C2) and 6-methyl-5,7-dihydroxy-4'- methoxyflavone (C6) along with the three known ones; hyperoside (C3), rutin (C4) and isoquercitrin (C5).

CONCLUSION

The methanolic extract of the leaves showed strong cytotoxic activity against Hepatocellular carcinoma cells (Hep G-2 cell line) and weak hepatoprotective effect.

Synthesis and Biological Evaluation of Some Novel Thiazole-Based Heterocycles as Potential Anticancer and Antimicrobial Agents

A novel series of thiazole-based heterocycles was synthesized using 1,3-dipolar cycloaddition reactions in the presence of chitosan-grafted-poly(vinylpyridine) as an eco-friendly biopolymeric basic catalyst. The molecular structure of the synthesized compounds was illustrated by spectroscopic and elemental analysis. Various in vitro biological assays were performed to explore the potential antitumor, antimicrobial and hepatoprotective activities of the newly synthesized compounds. The cytotoxic activities were assessed against human hepatocellular carcinoma (HepG-2), colorectal carcinoma (HCT-116) and breast cancer (MCF-7) cell lines and results revealed that all compounds displayed antitumor activities with the chlorine-containing derivatives, 11c and 6g, being the most potent. The majority of the tested thiazole derivatives exhibited satisfactory antibacterial activity towards the used gram positive and gram-negative bacterial species. Moreover, many derivatives showed weak hepatoprotective activity against CCl₄-induced hepatotoxicity.