Volume 20, Issue 2, 2020 April-June

Volume 20, No 2 Pages:
2020 April-June Articles: 2

Essential oils: a review on their salient biological activities and major delivery strategies

Essential oils are volatile, complex products of plants as secondary metabolites and include terpenes and their oxygenated derivatives, such as alcohols, aldehydes, esters, ketones, phenols and oxides. In recent years, out of 3000 essential oils obtained from plant origin only 300 essential oils have gained extensive attention for applications in various fields. In this review, we discuss the major biological activities associated with EOs as antimicrobial, antispasmodic, antioxidant, antiviral, anti-inflammatory, anthelmintic, insecticidal, antiparasitic, and cytotoxic agents. Different routes for delivery of essential oil along with the problems associated with essential oils like high volatility, low stability, permeability, bioavailability, poor water solubility, susceptibility to oxidation, decomposition, photosensitization and skin irritation are also highlighted. Furthermore, strategies to solve the mentioned problems are suggested by different nanoencapsulating systems. These include polymer-based nanocarriers, lipid-based nanocarriers and molecular complexes. It is believed that nanoencapsulation of essential oils will improve their therapeutic activity and delivery.

Screening of Callicarpa arborea and Hemigraphis alternata for antibacterial activity

Callicarpa arborea and Hemigraphis alternata are two medicinal plants claimed to have antimicrobial property in Indian traditional medicine. The methanol extracts of the stem bark of C. arborea and the leaves of H. alternata were prepared and tested for antibacterial activity using disk diffusion method. Four Gram-negative bacteria such as Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae and Salmonella typhimurium; and two Gram-positive bacteria such as Micrococcus luteus and Bacillus subtilis were used. C. arborea extract was effective against all the bacteria tested, while H. alternata did not show any inhibitory activity. These findings suggest that C. arborea is a good source of antibacterial compound.