Evaluation of purgative activity of roots of Rumex nepalensis

The methanol extract of Rumex nepalensis Spreng. roots at the oral dose of 100-400 mg/kg exhibited significant and dose-dependent purgative activity.     

Antidiarrhoeal activity of the bark extract of Careya arborea Roxb

The methanol extract of the Careya arborea Roxb. bark significantly reduced castor oil-induced diarrhoea in mice. This effect supports the local traditional use of the plant against diarrhoea.     

Evaluation and selection of multipurpose tree for improving soil hydro-physical behaviour under hilly eco-system of north east India

Soil hydro-physical behaviour was studied under a 20-year old agroforestry plantation consisting of five multipurpose tree species (Pinus kesiya Royle ex-Gordon, Alnus nepalensis D.Don, Parkia roxburghii G.Don, Michelia oblonga Wall. and Gmelina arboria Roxb.) maintained under normal recommended practices at Indian Council of Agricultural Research (ICAR) Complex, Umiam, Meghalaya, India. The aim was to select tree species, which could act as better bio-ameliorant as well as provides higher economic return in highly degraded soil of northeastern hill region of India. A site without vegetation (no tree) nearby the plantation was also selected as control for comparison. Soil samples for various hydro-physical analysis, were taken from 0–15 and 15–30 cm soil depth at a distance of 1 m from respective tree species during wet and dry season of 2003–2004. No appreciable differences in relative contents of textural separates of sand, silt and clay were observed among various tree covers. Surface cover with constant leaf litter fall and extensive root system increased soil organic carbon, helped in better soil aggregation, improved water transmissivity and infiltrability and in turn, reduced soil erosion in the present study. However, due to variation in quantity of leaf litter fall and root biomass, these parameters differed among tree species. Of the tree species, P. kesiya, M. oblonga and A. nepalensis were found to be rated best for bio-amelioration of soils as these tree covers had more root and shoot biomass and more litter fall compared to other species. However, considering both timber production and improvement in hydro-physical behaviour, M. oblonga was found best among the tested tree species. The study, thus, suggested that inclusion of tree species M. oblonga in agroforestry system is a viable option for natural resource management and could sustain long-term soil productivity in a highly degraded soil of this region as well as for food security of the resource poor people of North East India.     

Scavenging effect and antispasmodic activity of the essential oil of Cyclotrichium niveum

The radical scavenging and the spasmolitic activity of Cyclotrichium niveum essential oil were evaluated in vitro. It showed an IC(50) of 1750 microg/ml on DPPH method and dose dependently (0.1, 0.5 and 1 mg/ml) inhibits the contraction induced by carbachol on rabbit bladder from 15 to 100%. Moreover, it was able to inhibit the rat ileum muscle by 30 to 100%.     

Differing trophic niches of three French stygobionts and their implications for conservation of endemic stygofauna

1. Groundwater ecosystems represent the greatest proportion of unfrozen freshwater on Earth and harbour high numbers of rare taxa with restricted distributions. Stygofaunal abundance, species richness, and ecology play essential roles in groundwater ecosystem services and functioning, as well as providing an important contribution to global biodiversity. However, as global depletion and contamination of groundwater pose serious and often irreversible threats to stygofauna, more information is urgently needed about the ecology of rare groundwater species to guide effective strategies for their conservation or restoration.
2. In this study, analyses of carbon and nitrogen stable isotopes were used to compare and evaluate trophic niches and diets of a vulnerable stygobiont isopod, Gallasellus heilyi living in sympatry in French groundwater ecosystems with the isopod Caecosphaeroma burgundum and the amphipod Niphargus ladmiraulti.
3. Stable isotope results showed trophic niche partitioning among the three stygobiont species and indicated that G. heilyi and C. burgundum occupy the role of primary consumers and N. ladmiraulti that of predator. Moreover, although G. heilyi and C. burgundum were shown to rely on the same food sources, indicating similar diets, and their trophic niches did not overlap, suggesting trophic specialization.
4. The results suggest that detritus (i.e. decaying organic material) is an important food source for G. heilyi, and its availability could determine the survival of this endangered species. As a practical conservation measure for G. heilyi and the whole stygofauna community, we suggest reconnecting surface and subterranean ecosystems, as they probably were before natural sinks and many wells were filled up or closed.

     

Simple sequence repeats as useful resources to study transcribed genes of cotton

Microsatellites or Simple Sequence Repeats(SSRs) are informative molecular genetic markers in many crop species. SSRs are PCR-based, highly polymorphic, abundant, widely distributed throughout the genome and inherited in a co-dominant manner in most cases. Here we describe the presence of SSRs in cDNAs of cotton. Thirty one SSR primer pairs of 220 (∼14%) tested led to PCR amplification of discrete fragments using cotton leaf cDNA as template. Sequence analysis showed 25% of 24randomly selected cDNA clones amplified with different SSR primer pairs contained repeat motifs. We further showed that sequences from the SSR-containing cDNAs were conserved across G. barbadense and G. hirsutum, revealing the importance of the SSR markers for comparative mapping of transcribed genes. Data mining for plant SSR-ESTs from the publicly available databases identified SSRs motifs in many plant species,including cotton, in a range of 1.1 to4.8% of the submitted ESTs for a given species. This revised version was published online in August 2006 with corrections to the Cover Date.     

Comparative study of three different methods for the determination of aflatoxins in tahini

Aflatoxins spiked at three different levels (6.5, 13.0, and 19.5 microg/kg) in tahini, a sesame butter, were analyzed by using three different methods: high-performance liquid chromatography (HPLC), fluorometry, and enzyme-linked immunosorbent assay (ELISA). An immunoaffinity column was used for cleanup and purification of extracts prior to detection by HPLC and fluorometry. All methods were statistically evaluated for accuracy, precision, and simple correlations. Additionally, 14 tahini samples randomly obtained from Turkish retail markets were analyzed using an immunoaffinity column cleanup procedure coupled with the HPLC detection method. The fluorometric determination method involving an immunoaffinity column cleanup step was found to be highly correlated with the HPLC method (r = 0.978). Both methods were found to be effective due to their high recoveries and low variance for the prediction of total aflatoxin contamination in tahini samples. The ELISA method, due to its high variation in replicates, was found to be applicable only as a screening method. The survey study demonstrated the need for control of aflatoxin contamination of foodstuffs involving sesame seeds as an ingredient.     

Chemical characterization of Klason lignin preparations from plant-based foods

To analyze the accuracy of the Klason lignin method as applied for the determination of lignin contents in plant based-food products, Klason lignin preparations from curly kale, pears, whole wheat grains, and corn bran were chemically characterized. Characterization included routine ash and protein determinations and the extraction of fat/waxes as well as cutin/suberin depolymerization and extraction of the liberated monomers. Fat/wax and cutin/suberin amounts in the Klason lignin preparations were determined gravimetrically, and their compositions were analyzed by using GC-MS. Typical fat, wax, and cutin (and suberin) constituents such as saturated and unsaturated fatty acids, hydroxy and/or epoxy fatty acids, and phenolic acids were identified in all samples, whereas the detection of long-chain hydrocarbons, alcohols, and ketones, sterols, stanols, and dioic acids was dependent on the sample analyzed. Estimation of the contribution of non-lignin compounds to the Klason lignin contents reduced the noncorrected Klason lignin contents of the insoluble fibers from 28.7% (kale), 22.8% (pear), 14.8% (wheat), and 9.9% (corn) to maximum lignin contents of 6.5% (kale), 16.4% (pear), 4.9% (wheat), and 2.3% (corn). These data demonstrate that certain commonly used statements such as "cereal brans are highly lignified" need to be revised.