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Volatile oil from the leaves of Eucalyptus citriodora, collected from Yercaud in South India, was isolated by hydrodistillation and analysed by GC/FD and GC/MS. Citronellal (81.2%) and citronellol (10.62%) were the major constituents in the leaf oil. Total monoterpene content in the leaf oil was 99.37% (monoterpene hydrocarbons 0.46%, oxygenated monoterpenes 98.91%), whereas the sesquiterpene content was very low at 0.57% (sesquiterpene hydrocarbons 0.40%, oxygenated sesquiterpenes 0.17%). In vitro antibacterial activity of E. citriodora leaf oil against three Gram-positive and six Gram-negative bacteria was tested by disc diffusion and broth micro dilution assays. The minimum inhibitory concentration and minimum bactericidal concentration of Bacillus subtilis, Staphylococcus aureus, Klebseilla pneumoniae, Pseudomonas aeruginosa and Serratia marcescens were determined as 0.4/0.8, 0.2/0.4, 0. 1/0.2, 0.4/0.8 and 0. 1/0.4 (%, v/v), respectively. Bacillus cereus, Escherichia coli and Proteus vulgaris showed very low susceptibilities in these assays. E. citriodora leaf oil showed total inhibition against the growth of Salmonella typhi, the causative organism of typhoid fever, in both disc diffusion and broth micro dilution assays. Citronellal/citronellol-type E. citriodora leaf oil could also be utilized for the development of potential therapeutic products to treat illnesses caused by antibiotic resistant Salmonella. Key words: Eucalyptus citriodora, leaf essential oil, GC/FID, GC/MS, antibacterial activity, Salmonella typhi.

The essential oil obtained by hydrodistillation from the root of Naregamia alata was analyzed. Thirty four compounds were identified by mass spectral database search and comparison of linear retention indices. γ-Himachalene (11.2%), β-Caryophyllene (10.8%) and β-Sesquiphellandrene (10.7%) were the major constituents. The antibacterial activity of the root oil was studied by the disc diffusion assay. The oil showed significant antibacterial activity against Gram-positive and Gram-negative bacteria. This is the first report on the essential oil composition and antibacterial activity of N. alata. [ABSTRACT FROM AUTHOR]

In this study, polysaccharides were isolated from Ganoderma lucidum (Polyporaceae) and their antitumor and anti-inflammatory activities were investigated using in vivo models. Potential antitumor activity was shown by G. lucidum polysaccharides (GLP) against solid tumor induced by Ehrlich's ascites carcinoma cells. GLP at 100 mg kg(-1) body mass showed 80.8 and 77.6% reduction in tumour volume and tumour mass, respectively, when administered 24 h after tumour implantation. Again, GLP at the same dose but when administered prior to tumour inoculation, showed 79.5 and 81.2% inhibition of tumour volume and tumour mass, respectively. GLP showed significant dose-dependent activity in carrageenean-induced (acute) and formalin-induced (chronic) inflammation assays. At 100 mg kg(-1), GLP exhibited 57.6 and 58.2% inhibition in carrageenean-induced and formalin-induced assays, respectively.

Essential oil from the fruits of Amomum cannicarpum (Wight) Bentham ex Baker (Zingiberaceae) was hydrodistilled and characterized by gas chromatography-mass spectrometry (GC-MS). Major constituents of the oil were beta-pinene (14.00%), elemol (10.45%) and alpha-cadinol (8.50%). Thirty-three (91.48%) out of forty-one constituents were identified by GC-MS and subsequent data analysis. Antimicrobial activity of the oil against Gram-positive and Gram-negative bacteria and some fungi, was determined by the disc diffusion assay. The oil showed good antibacterial activity against Salmonella typhi, Pseudomonas aeruginosa and Proteus vulgaris and very good antifungal activity against Candida albicans and C. glabrata.

Volatile oil from the rhizomes of Zingiber nimmonii (J. Graham) Dalzell was isolated, characterized by analytical gas chromatography and gas chromatography-mass spectroscopy. Sixty-five constituents accounting for 97.5% of the oil were identified. Z. nimmonii rhizome oil is a unique caryophyllene-rich natural source with isomeric caryophyllenes, beta-caryophyllene (42.2%) and alpha-humulene (alpha-caryophyllene, 27.7%), as its major constituents along with traces of isocaryophyllene. The rhizome oil contained 71.2% sesquiterpenes, 14.2% oxygenated sesquiterpenes, 8.9% monoterpenes, 1.9% oxygenated monoterpenes and 1.3% non-terpenoid constituents. The antimicrobial activity of the oil was tested against human and plant pathogenic bacteria and fungi. The oil showed significant inhibitory activity against the fungi, Candida glabrata, C. albicans and Aspergillus niger and the bacteria Bacillus subtilis and Pseudomonas aeruginosa. No activity was observed against the fungus Fusarium oxysporum.