Antibacterial activity of essential oils of edible spices, Ocimum canum and Xylopia aethiopica.

UNLABELLED: The essential oils of 2 Cameroonian spices, namely, Xylopia aethiopica and Ocimum canum, were chemically investigated and screened for their antibacterial activity. The essential oils were analyzed by means of GC, GC/MS, and NMR. X. aethiopica oil contained myrtenol (12%), a monoterpenoid in highest concentration. The essential oil of O. canum belonged to the known linalool (44%) rich chemotype. The results of the antibacterial screening against the food spoiling bacteria revealed a significant and broad spectrum of activity for these essential oils. The present material of X. aethiopica, which is having myrtenol in relatively higher concentration, has shown moderate antibacterial activity. The bioassay-guided fractionation of Ocimum canum oil through flash chromatography showed that minor compounds, namely, α-terpineol, chavicol, chavibetol, and trans-p-mentha-2,8-dien-ol, significantly contributed for the overall activity observed. Hence, these results evidenced the possible potential of the essential oil of O. canum as a suitable antibacterial for controlling food-borne pathogens whereas the X. aethiopica oil has moderate possibility. PRACTICAL APPLICATION: There is a strong global demand for the microbe-free, safe, and healthy foods. In this study, we showed that the essential oil of O. canum (wild basil) can be used as antibacterial for food items. Also, we showed that a value addition in the antibacterial potential of O. canum oil can be done by processing the essential oil through flash chromatographic separations.

Zantholic acid, a new monoterpenoid from Zanthoxylum zanthoxyloides.

From the extract of Zanthoxylum zanthoxyloides fruits, a new menthane monoterpenoid, (4R,7R)-8-carboxy-7,9-dihydroxy-trans-menthane, tentatively, named as zantholic acid along with several known compounds was isolated. Its structure was determined using spectroscopic methods. The cytotoxic activity of zantholic acid against a panel of cancer cell lines was evaluated using the MTT assay. The results show that zantholic acid possesses a selective cytotoxic activity towards breast cancer cell lines.

Antibacterial, cytotoxic activities and chemical composition of fruits of two Cameroonian Zanthoxylum species.

ETHNOPHARMACOLOGICAL RELEVANCE: Zanthoxylum leprieurii (Syn. Fagara leprieurii) is a plant extensively used by traditional healers in Cameroon for the treatment of stomach disorders, gonorrhea, intestinal parasites and sterility. The infusion from the fruit is taken in Cameroon for the treatment of sickle cell anemia, as well. Similarly, the roots of Zanthoxylum zanthoxyloides (Syn. Fagara zanthoxyloides) are also used for wound dressing, sickle cell anemia and as pain reliever, in addition to the uses mentioned for Zanthoxylum leprieurii. AIM OF THE STUDY: To scientifically validate their traditional use, the in vitro antimicrobial and anticancer assays were performed. In addition, chemical compositions of their fruit extracts and essential oils were also studied. MATERIAL AND METHODS: The chemical compositions of their essential oils and methanol extracts were studied. GC and GC-MS were used for analyzing the essential oils while various chromatographic methods were used to isolate the pure compounds from methanol extracts. MTT assay was used for the cytotoxic studies of methanol extracts, their fractions and some pure compounds. Antimicrobial activity of methanol extracts, some isolated compounds as well as essential oils was tested against a panel of human pathogenic bacteria by diffusion and dilution methods. RESULTS: The principal constituents of the essential oil of Zanthoxylum zanthoxyloides were identified as citronellol and geraniol whereas Zanthoxylum leprieurii was rich in E-ß-ocimene. Furthermore, we report for the first time, the presence of 7,8-dimethoxycoumarin and sinapic acid in the methanol extract of Zanthoxylum leprieurii. In vitro bioassays reveal that the methanol extracts, essential oil and some of the isolated compounds from fruits of both the plants exhibit moderate anticancer and antimicrobial activities. CONCLUSION: Altogether, the present findings justify the traditional use of Zanthoxylum zanthoxyloides and Zanthoxylum leprieurii in the treatment of stomach disorders and cancer disease. The antimicrobial properties in the essential oil of Zanthoxylum zanthoxyloides are of additional significance.

Cysteine proteases from the Asclepiadaceae plants latex exhibited thrombin and plasmin like activities.

In the present study we evaluated the presence of cysteine protease from the latex of four plants Asclepias curassavica L., Calotropis gigantea R.Br., Pergularia extensa R.Br. and Cynanchum puciflorum R.Br. belongs to the family Asclepiadaceae. Cysteine proteases from these plants latex exhibited both thrombin and plasmin like activities. Latex enzyme fraction in a concentration dependent manner induced the formation of clot in citrated blood plasma. Direct incubation of fibrinogen with latex enzyme fraction resulted in the formation of fibrin clot similar to thrombin enzyme. However prolonged incubation resulted in degradation of the formed fibrin clot suggesting plasmin like activity. Latex enzyme fraction preferentially hydrolyzed Aalpha and Bbeta chains of fibrinogen to form fibrin clot. Latex enzyme fraction also hydrolyzed the subunits of fully cross linked fibrin efficiently, the order of hydrolysis was alpha-polymer > alpha-chains > beta-chain and gamma-gamma dimer. Cysteine proteases from all the four Asclepiadaceae plants latex exhibited similar action on fibrinogen and fibrin. This study scientifically validate the use of plant latex in stop bleeding and wound healing by traditional healers all over the world.