Design and production of methyl jasmonate nanoemulsions using experimental design technique and evaluation of its anti-cancer efficacy.

Methyl jasmonate (MJ), a plant-derived stress hormone, has been shown to be a promising anti-cancer agent with high selectivity toward cancerous cells. The aim of the present study was to design a MJ loaded nanoemulsion (NE) to overcome the low MJ water solubility and also improve its anti-cancer efficiency. Box-Behnken design (BBD) was employed to optimize the composition effect of three independent manufacturing variables on two responses including average droplet size and poly dispersity index (PDI). ANOVA analysis indicated that both of the studied responses were well fitted by resultant quadratic models with the coefficient of determinations (R2) 0.994 and 0.975, respectively. The actual average droplet size 75.06 nm and PDI 0.017 obtained for the optimum MJNE was in good agreement with those values predicted with numerical optimization. Physicochemical characterization indicated that the optimum MJNE was transparent, isotropic, spherical and sterically stabilized. MTT assay indicated that MJNE was more efficacious in killing cancer cells than MJ solution. Cell cycle analysis revealed that MJNE induced a stronger sub-G1 arrest than MJ solution. A considerable absence of toxicity was achieved for MJNE and blank NE in HUVEC normal cells. These results may provide strong support to develop a NE delivery system as a promising carrier for improving the safety and anti-cancer efficacy of MJ.

Chemical composition and in vitro antimicrobial activity of the essential oil of Cyclotrichium leucotrichum from Iran.

The objective of this study was to investigate in vitro antimicrobial activity and composition of the essential oil of Cyclotrichium leucotrichum growing wild in Iran. The essential oil was obtained by hydro-distillation and analysed by GC-FID and GC/MS. Fifty-nine components representing 98.9% of the total oil were characterised. The essential oil which has 1,8-cineol (14.8%), elemol (12.6%), spathulenol (9.4%), E-caryophyllene (5.7%) and hinesol (5.7%) as its main components, exhibited moderate activity against seven bacteria and a yeast, Candida albicans, with minimum inhibitory concentration values ranging from 0.5 to 64 mg mL(-1) and minimum bactericidal concentration values ranging from 2 to >64 mg mL(-1), respectively. The best inhibitory effects were against three gram-positive bacteria and tested yeast, C. albicans.

Biotechnological production of taxol and related taxoids: current state and prospects.

Taxol is one of the most effective anti-cancer drugs ever developed. The natural source of taxol is the inner bark of several Taxus species, but it accumulates at a very low concentration and with a prohibitively high cost of extraction. Another problem is that the use of inner bark for taxol production implies the destruction of yew trees. For all these reasons, the growing demand for taxol greatly exceeds the supply that can be sustained by isolation from its natural source and alternative sources of the drug are being sought. Although taxol has been prepared by total synthesis, the process is not commercially viable. Taxol can also be semisynthetically produced via the conversion of baccatin III or 10-deacethylbaccatinIII found in Taxus needles but the cost and difficulty of the extraction process of the semisynthetic precursors are also very high. The most promising approach for the sustainable production of taxol and related taxoids is provided by plant cell cultures at an industrial level. Taxol is currently being clinically used against different tumour processes but due to the difficulty of its extraction and formulation, as well as the growing demand for the compound, new taxol analogues with improved properties are being studied. In this revision we discuss current research in the design of new taxol-related compounds, the chemical structure/anti-cancer activity relationship and new formulations of the drug. We also consider the optimizing strategies to improve taxol and related taxoid production in cell cultures, as well as the current knowledge of taxol metabolism, all of which are illustrated with examples, some of them from our own research.

Essential oil composition and antibacterial activity of Thymus caramanicus at different phenological stages.

Thymus species are well known as medicinal plants because of their biological and pharmacological properties. Thymus caramanicus is an endemic species grown in Iran. Variation in the quantity and quality of the essential oil of wild population of T. caramanicus at different phenological stages including vegetative, floral budding, flowering and seed set are reported. The oils of air-dried samples were obtained by hydrodistillation. The yields of oils (w/w%) at different stages were in the order of: flowering (2.5%), floral budding (2.1%), seed set (2.0%) and vegetative (1.9%). The oils were analyzed by GC and GC-MS. In total 37, 37, 29 and 35 components were identified and quantified in vegetative, floral budding, full flowering and seed set, representing 99.3, 98.6, 99.2 and 97.8% of the oil, respectively. Carvacrol was the major compound in all samples. The ranges of major constituents were as follow: carvacrol (58.9-68.9%), p-cymene (3.0-8.9%), γ-terpinene (4.3-8.0%), thymol (2.4-6.0%) and borneol (2.3-4.0%). Antibacterial activity of the oils and their main compounds were tested against seven Gram-positive and Gram-negative bacteria by disc diffusion method and determining their minimum inhibitory concentration (MIC) values. The inhibition zones (IZ) and MIC values for bacterial strains, which were sensitive to the essential oil of T. caramanicus, were in the range of 15-36mm and 0.5-15.0mg/ml, respectively. The oils of various phenological stages showed high activity against all tested bacteria, of which Bacillus subtilis and Pseudomonas aeruginosa were the most sensitive and resistant strains, respectively. Thus, they represent an inexpensive source of natural antibacterial substances that exhibited potential for use in pathogenic systems.