Chemical composition, antibacterial and antifungal activities of the essential oil of Haplophyllum tuberculatum from Oman.

The chemical composition of the essential oil of Haplophyllum tuberculatum (Forsskal) A. Juss (Rutaceae) was analyzed by gas chromatography-mass spectral (GC-MS) and 13C NMR spectroscopy. Thirty compounds, constituting about 99.7% of the total oil, were identified. The most abundant oil components are beta-phellandrene (23.3%), limonene (12.6%), (Z)-beta-ocimene (12.3%), beta-caryophyllene (11.6%), myrcene (11.3%), and alpha-phellandrene (10.9%). Ten microlitres (25 mg) of pure oil partially inhibited the growth of Escherichia coli, Salmonella choleraesuis, and Bacillus subtilis to the same extent as 0.10 microg of gentamycin sulfate. The oil also affected the mycelial growth of Curvularia lunata and Fusarium oxysporium in a dose-dependent manner but had no effect on the germination of their spores.

Supercritical fluids and their applications in biotechnology and related areas.

This article serves as an overview, introducing the currently popular area of supercritical fluids (SFs) and their uses in biotechnology and related areas. It covers the fundamentals of supercritical science and moves on to the biotechnological and associated applications of these fluids. Subject areas covered include pure substances as supercritical fluids, the properties of supercritical fluids, organic cosolvents, solubility, and the following applications: extraction, chromatography, reactions, particle production, deposition, and the drying of biological specimens. Within each application, and where possible, the basic principles of the technique are given, as well as a description of the history, instrumentation, methodology, uses, problems encountered, and advantages over the traditional, nonsupercritical methods.