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Here we report a unique plant‐insect interaction between the leafhopper Aloka depressa (tribe Phlogisini) and the host liana, Diploclisia glaucescens, from a Botanic Garden located at the southern edge of Western Ghats in India.Field observations and SEM micrographs were employed to derive evidences on this rare plant‐insect interaction. 20‐Hydroxyecdysone (20E), insect moulting hormone, was detected and quantified in the host plant D. glaucescens using HPTLC‐densitometry. 20E was isolated and characterized from D. glaucescens using column chromatography, 1H‐, 13C‐NMR and HR‐MS. 20E was also detected in A. depressa excrement using HPTLC‐densitometry.The leafhopper A. depressa is functioning as a 'sharpshooter' drawing nutrients from the host liana, D. glaucescens, and flinging the waste fluid as droplets through their tail ends. SEM micrographs of A. depressa revealed its external morphological features, characteristic of a sharpshooter. We quantified 20E (0.44–1.44%, dry wt.) in various parts of D. glaucescens. 20E (1.47%, dry wt.) was also detected in the excrement of A. depressa.This plant (D. glaucescens)‐insect (A. depressa) association crucially is not damaging the host liana. Considering the diseases caused by sharpshooting leafhoppers in the Americas, this association and the survival of the host plant (D. glaucescens) is illustrating a unique plant‐insect interaction. [ABSTRACT FROM AUTHOR]

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.

Bamboos are one of the fastest growing plants on Earth, and are widely considered to have high ability to capture and sequester atmospheric carbon, and consequently to mitigate climate change. We tested this hypothesis by measuring carbon dioxide ( CO2) emissions from bamboo culms and comparing them with their biomass sequestration potential. We analysed diurnal effluxes from Bambusa vulgaris culm surface and gas mixtures inside hollow sections of various bamboos using gas chromatography. Corresponding variations in gas pressure inside the bamboo section and culm surface temperature were measured. SEM micrographs of rhizome and bud portions of bamboo culms were also recorded. We found very high CO2 effluxes from culm surface, nodes and buds of bamboos. Positive gas pressure and very high concentrations of CO2 were observed inside hollow sections of bamboos. The CO2 effluxes observed from bamboos were very high compared to their carbon sequestration potential. Our measurements suggest that bamboos are net emitters of CO2 during their lifespan. [ABSTRACT FROM AUTHOR]

Carnivorous plants acquire most of their nutrients by capturing ants, insects and other arthropods through their leaf-evolved biological traps. So far, the best-known attractants in carnivorous prey traps are nectar, colour and olfactory cues. Here, fresh prey traps of 14 Nepenthes, five Sarracenia, five Drosera, two Pinguicula species/hybrids, Dionaea muscipula and Utricularia stellaris were scanned at UV 366 nm. Fluorescence emissions of major isolates of fresh Nepenthes khasiana pitcher peristomes were recorded at an excitation wavelength of 366 nm. N. khasiana field pitcher peristomes were masked by its slippery zone extract, and prey capture rates were compared with control pitchers. We found the existence of distinct blue fluorescence emissions at the capture spots of Nepenthes, Sarracenia and Dionaea prey traps at UV 366 nm. These alluring blue emissions gradually developed with the growth of the prey traps and diminished towards their death. On excitation at 366 nm, N. khasiana peristome 3:1 CHCl3-Me OH extract and its two major blue bands showed strong fluorescence emissions at 430-480 nm. Masking of blue emissions on peristomes drastically reduced prey capture in N. khasiana pitchers. We propose these molecular emissions as a critical factor attracting arthropods and other visitors to these carnivorous traps. Drosera, Pinguicula and Utricularia prey traps showed only red chlorophyll emissions at 366 nm. [ABSTRACT FROM AUTHOR]

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]

Abstract: The essential oil obtained by hydrodistillation of the rhizomes of Amomum cannicarpum was analyzed by GC and GC/MS. Thirty-four compounds were identified, of which the major components were β-terpineol (13.4%), β-pinene (9.4%) and α-pinene (6.9%). The essential oil showed significant antimicrobial activity. [Copyright &y& Elsevier]

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.