Development of an Extractive Spectrophotometric Method for the Determination of Copper(II) in Leafy Vegetable and Pharmaceutical Samples Using 2–acetylpyridine 4–phenyl –3-thiosemicarbazone (APPT)

A highly sensitive extractive spectrophotometric method has been developed for the determination of copper(II) using 2-acetylpyridine-4-phenyl-3-thiosemicarbazone as an analytical reagent. The APPT forms reddish brown complex of copper(II) at a pH range of 3.0-5.5, and the complex was extracted into n-butanol. The Cu(II)-APPT complex shows maximum absorbance at 440 nm, with molar absorptivity and Sandell’s sensitivity being 2.16 x 104 L mol-1cm-1 and 2.94 x 10-3µg cm-2, respectively. The system obeys Beer’s law in the range of 0.2-5.0 mg/L. The regression coefficient of the Beer’s law straight line is 0.338, and the correlation coefficient is 0.96. The detection limit of the method is 0.0065 μg mL-1. Most of the common metal ions generally found associated with copper do not interfere. The repeatability of the method was checked by finding the relative standard deviation. The developed method has been successfully employed for the determination of copper (II) in leafy vegetable and pharmaceutical samples. The method is evaluated by analyzing samples from the Bureau of Analyzed Samples (BCS 233, 266, 216/1, 207, and 179) and by inter-comparison of experimental values using AAS.Keywords: Cu (II), leafy vegetables, Pharmaceuticals,Extractive spectrophotometric method, 2-acetylpyridine-4-phenyl-3-thiosemicarbazone (APPT

Prospecting for Camptothecines from Nothapodytes nimmoniana in theWestern Ghats, South India: Identification of High-Yielding Sources of Camptothecin and New Families of Camptothecines

Camptothecin (CPT), a monoterpene alkaloid, is an important anti-cancer compound obtained from several plant sources including Camptotheca acuminta (from China) and Nothapodytes nimmoniana (from India). Currently, by far the highest levels of CPT (approximately 0.3% w/w) are reported from Nothapodytes nimmoniana, a small tree distributed in the Western Ghats, India. In recent years because of the heavy demand, there has been a serious threat of extinction of the populations of the tree in the Western Ghats forest of south India. Several studies have chemically profiled populations of the species in the Western Ghats to identify sources of high yield and therefore to enable the sustainable production and harvesting of CPT. In this study, using both high-performance liquid chromatography and liquid chromatography-mass spectrometry, we report for the first time the identification of trees that produce at least 5- to 8-fold more CPT than hitherto reported. Furthermore, we show for the first time the production of a few minor camptothecines, including 10-hydroxy camptothecin, in the stem and root bark extracts of the tree. These results have important implications for not only harnessing the high-yielding individuals for clonal multiplication but also for exploiting some of the minor camptothecines, which also have been shown to have important anti-cancer and anti-viral activity

Climate change, flooding and food security in south Asia

Climate change, Flooding, Food security, Poverty, Women, Children,

Effects of host plant genotype and seedbank density on Striga reproduction

Prevention of seed input to the seedbank of Striga hermonthica-infested fields is an important objective of Striga management. In three consecutive years of field experimentation in Mali, Striga reproduction was studied for 10 sorghum genotypes at infestation levels ranging from 30 000 to 200 000 seeds m−2. Host resistance was identified as an important determinant of Striga reproduction, with the most resistant genotypes (N13, IS9830 and SRN39) reducing Striga reproduction by 70–93% compared with the most susceptible genotype (CK60-B). Seedbank density had a significant effect on Striga seed production. Higher seedbank density resulted in more Striga plants, which led to increased intra-specific competition and consequently a reduced level of reproduction per plant. For the most susceptible sorghum genotypes, density dependence also occurred in the earlier belowground stages. Striga reproduction continued beyond harvest. At the high infestation level just 8% of the total reproduction was realised after harvest, whereas at the low infestation level 39% was attained after harvest. Even though host-plant genotype plays a significant role in Striga reproduction, calculations indicated that only at very low infestation levels the use of the most resistant genotype was able to lower the Striga seedbank

Carbonate xenoliths hosted by the Mesoproterozoic Siddanpalli Kimberlite Cluster (Eastern Dharwar craton): Implications for the geodynamic evolution of southern India and its diamond and uranium metallogenesis

A number of limestone and metasomatised carbonate xenoliths occur in the 1,090 Ma Siddanpalli kimberlite cluster, Raichur kimberlite Field, Eastern Dharwar craton, southern India. These xenoliths are inferred to have been derived from the carbonate horizons of the Kurnool (Palnad) and Bhima Proterozoic basins and provide evidence for a connection between these basins in the geological past. A revised Mesoproterozoic age is proposed for the Bhima and Kurnool (Palnad) basins based on this kimberlite association and is in agreement with similar proposals made recently for the Chattisgarh and Upper Vindhyan sediments in Central India. The observed Bhima–Kurnool interbasinal uplift may have been caused by: (1) extension- or plume-related mafic alkaline magmatism that included the emplacement of the southern Indian kimberlites at *1.1 Ga, (2) mantle plume-related doming of the peninsular India during the Cretaceous, or (3) Quaternary differential uplift in this region. It is not possible, with the currently available geological information to constrain the exact timing of this uplift. The deep erosion of primary diamond sources in the Raichur kimberlite Field in the upper reaches of the Krishna River caused by this uplift could be the elusive source of the alluvial diamonds of the Krishna valley. Mesoproterozoic sedimentary basins can host world class unconformity-type uranium deposits. In light of its inferred Mesoproterozoic age, a more detailed stratigraphic and metallogenic analysis of the Kurnool basin is suggested for uranium exploration