New Phytochemical Constituent and Bioactivities of Horwoodia dicksoniae and Rumex cyprius.
BACKGROUND
Many plants growing in Saudi Arabia are used in folk medicine for treatment of several diseases.


OBJECTIVE
Information of the chemical constituents and biological activities of plants is desirable for the discovery of therapeutic agents and discovering the actual value of folkloric remedies.


METHODS
The compounds were isolated and purified using silica gel column chromatography and preparative high-performance liquid chromatography-diode array detector (HPLC-DAD) Method. The alcoholic extracts of these plants were evaluated for biological activities.


RESULTS
Isolation and characterization of 1-feruloyl-β-D-glucopyranoside (1) as well as new secondary metabolite tryptophan methyl ester (2) were isolated for the 1(st) time from the Horwoodia dicksoniae. The three flavones were isolated from Rumex cyprius identified as isoorientin (3), vitexin (4), and Cynarosid (5). The structures of these compounds were characterized by nuclear magnetic resonance and mass spectrometry analysis and comparing with literature. The compounds were isolated and purified using silica gel column chromatography and preparative HPLC-DAD Method. The alcoholic extracts of these plants were evaluated for antimicrobial activities against two Gram-positive bacteria, two Gram-negative bacteria, and four pathogenic fungi. Both plants showed good activities against Syncephalastrum racemosum and Streptococcus pneumoniae with minimal inhibitory concentrations (MICs) 0.98 and 1.95 μg/mL, respectively. H. dicksoniae showed good activity against Aspergillus fumigates with an MIC 1.95 μg/mL. The two extracts showed also effective free radical scavenging activities in the 1,1-diphenyl-2-picrylhydrazyl assay. H. dicksoniae exhibited remarkable cytotoxic activity against Human breast cancer mammary cancer cells-7, Human liver cancer human hepatoma carcinoma cells-2, and human lung carcinoma (A-549) cell lines.


CONCLUSIONS
It was suggested that further work should be carried out to isolate, purify, and characterize the active constituents responsible for the activity of these plants.


CONCLUSIONS
New secondary metabolite Tryptophane methyl ester as well as 1-feruloyl-β-D-glucopyranoside were isolated for the first time from the HD.Isoorientin, vitexin and Cynarosid were isolated from RC.HD exhibited good activity against Aspergillus fumigates with an MIC 1.95 µg mL(-1).HD showed significant cytotoxic activity against Human breast cancer (MCF-7), Human liver cancer (HepG-2) and Human lung carcinoma (A-549) cell lines.
Department of Natural Product and Complementary Medicine, Faculty of Pharmacy, Northern Border University, Rafha, Kingdom of Saudi Arabia; Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt.
Mohammed F
MF
Abdelwahab
Department of Clinical Pharmacology, Faculty of Pharmacy, Northern Border University, Rafha, Kingdom of Saudi Arabia.
Sibghatullah
S
Sangi
Department of Biology, Faculty of Science and Arts, Northern Border University, Rafha, Kingdom of Saudi Arabia; Department of Botany and Microbiology, Faculty of Science, Minia University, Minia, Egypt.
Hussam H
HH
Arafat
Department of Pharmacognosy, Faculty of Pharmacy, Al-Azhar University, Cairo, Egypt.
Ehab A
EA
Ragab
Antimicrobial; Rumex; antioxidant; cytotoxicity; horwoodia