Length–weight relationship of clown knifefish Chitala chitala (Hamilton 1822) from the River Ganga basin, India

This study describes the length–weight relationship (LWR) of the clown knifefish, Chitala chitala, in the River Ganga basin, India. A total of 221 specimens ranging from 31 to 120 cm total length (TL) and 550 to 12 000 g total weight (TW) were collected. Chitala chitala constitutes an important component of riverine fisheries of India and is considered one of the most commercially important and highly priced foods in addition to being an aquarium fish. The species has recently undergone heavy fishing pressure, leading to an alarming decline in natural populations and deserving of high conservation importance. Length–weight relationships of C. chitala from wild populations had not yet been studied. Hence, the study objective was to evaluate length–weight relations of C. chitala from eleven populations in order to help in conservation and management of the riverine population.     

Evaluation of Antimicrobial Activity of Bauhinia purpurea Leaves Under In Vitro Conditions

This study was undertaken with an objective of testing the antibacterial and antifungal activities of Bauhinia purpurea leaves and identifying the bioactive compounds. The antimicrobial activity of leaf extract was determined in aqueous and organic extracts and the minimum inhibitory concentration (MIC) against six species of pathogenic and non-pathogenic microorganisms: Bacillus subtilis, Staphylococcus aureus, Salmonella typhi, Escherichia coli, Pseudomonas aeruginosa and Candida albicans using the disk diffusion method. The chemical constituents of organic plant extract were separated by thin layer chromatography and purified by column chromatography and further identified by gas chromatography–mass spectrometry (GC–MS) analysis. Significant inhibitory activity was observed with methanol extracts of plant against the test microorganisms while less antibacterial activity was observed in hexane, acetone and aqueous extracts. MIC of B. purpurea extract was ≤1,500 μg/ml against S. aureus and B. subtilis while this extract showed no inhibition against Gram-negative S. typhi, E. coli and P. aeruginosa or against fungus C. albicans. Eleven compounds were identified in B. purpurea leaf extract by GC–MS analysis. The composition of B. purpurea revealed the presence of lupeol, stigmasterol, lanosterol, ergosterol, beta-tocopherol, phytol, hexadeconic acids, hexadeconic acids methyl esters, octadecadienoic acids and octadecatrienoic acid. Stigmasterol and lupeol were the most abundant (34.48 and 15.63 %). Other phytosterols like lanosterol (4.15 %) and ergosterol (2.82 %) were also found to be present in this extract.     

Studies on substituted benzo[h]quinazolines,benzo[g]indazoles,pyrazoles, 2,6-diarylpyridines as anti-tubercular agents

Various substituted 5,6-dihydro-8-methoxybenzo[h]quinazolin-2-amine, 1-(3-(4-alkoxyphenyl)-7-methoxy-3,3a,4,5-tetrahydro-2H benzo[g]indazol-2-yl)ethanone, pyrazole and 2,6-diarylpyridine derivatives have been synthesized in good yields by an efficient methodology. The synthesized compounds (4–23) were evaluated for their in vitro anti-tubercular activity against Mycobacterium tuberculosis H37Rv strain. Compounds 6a, 6c, 8a, 19a and 19e exhibited significant anti-tubercular activity at MIC values 50, 100, 50, 25 and 100 μM concentration. In vitro cytotoxicity data using THP-1 cells indicated that most active compound 19a is safe as its MIC value is much lower than the cytotoxic value.     

Daily Increments of Light Hours Near Vernal Equinox Synchronize Circannual Testicular Cycle of Tropical Spotted Munia

In some long-lived organisms, particularly in tropical birds and migrants that spend part of the year close to the equator, endogenous circannual rhythms have been demonstrated in seasonal events like reproduction, molt, and migration. These, like the circadian rhythms, are expressed only in constant conditions of illumination with a periodicity deviating from 1 yr. If birds followed this periodicity, they would soon be out of phase with the annual calendar and perish and, therefore, they would need to be synchronized. However, almost nothing is known as to how synchronization is achieved in birds. Herein, with the help of a suitable model, viz., the tropical spotted munia and long-term experiments conducted in series over a 5-yr period, we provide direct evidence for the first time indicating that the segment of annual photocycle with maximal rate of increase prior to vernal equinox (approximately between mid-February and mid-March) synchronizes the circannual reproductive cycle with the monsoon period of ample food supply through a phase delay. Data also indicate, contrary to the prevalent view, that birds in the tropics can perceive minor changes in day-length, that birds respond to progressive changes in day-length as distinct from responding to fixed photoperiods of particular durations, and that birds can actually distinguish the quality of the environmental signal, viz., vernal equinox from early spring, or increasing days of spring from decreasing days of autumn. The underlying mechanisms, although yet to be identified, appear to involve a gonado-inhibitory rather than the conventional gonado-stimulatory response to increasing day-length. The photoperiodic responses of spotted munia are distinctly different from that of any “long-day” birds described thus far and do not conform to the prevalent “circadian coincidence” hypothesis of photoperiodism.     

Amide derivatives of 9,11-seco-estra-1,3,5(10)-trien-11-oic acid as modified orally active estrogen agonists with moderate antagonistic activity

Synthesis of amide derivatives of 9,11-seco-estra-1,3,5(10)-trien-11-oic acid containing alkyl and aromatic amine residues has been carried out with an aim to prepare orally active estrogen antagonists. Modification of the estradiol molecule in the form of C-seco-amide derivatives has led to their high oral absorption. Compounds 7 an n-propyl amide, 8 an n-butyl amide, and 16 a p-anisidyl amide of C-seco-estrane showed significant estrogen antagonistic activity (>20%), while, the majority of compounds possessed high estrogen agonistic activity on oral administration at 10mg/kg dose in rats.     

Synthesis of a novel plant growth promoter from gallic acid

Gallic acid has been modified to naphthophenone derivatives with esterified fatty acid side chain. Compound 12, an ethyl crotonate ester of naphthophenone derivative has shown potent auxin like growth promoter activity. This is the first example of naphthophenone derivatives with plant growth promoting activity.     

Screening interspecific hybrids of<Emphasis Type="Italic"> Populus</Emphasis> (<Emphasis Type="Italic">P. ciliata</Emphasis> ×<Emphasis Type="Italic"> maximowiczii</Emphasis>) using AFLP markers

Hybrids of Populus ciliata × maximowiczii are very vigorous and outperform both the parents in growth performance and yield. Genetic evaluation of 24 of these interspecific hybrids along with the two mother trees (Populus ciliata), and five male-parent (Populus maximowiczii) genotypes was carried out using the AFLP marker assay. Eight AFLP primer combinations detected 428 markers, of which 280 (66%) were polymorphic. Genetic relationships within the samples were evaluated by generating the similarity matrix based on Jaccards coefficient. The phenetic dendrograms, as well as the PCO plots, separated the hybrids and the two parent species into three distinct clusters. The hybrids grouped closer to the P. ciliata (female parent) cluster as compared to the P. maximowiczii (male parent) cluster. The hybrid cluster contained internal groupings, which correlated to some extent with growth performance. The four best performing hybrids (42m1, 65m1, 23m2, Cm2-5-20/91) formed a distinct sub-cluster. Data from a single primer combination was sufficient for distinguishing the hybrids from the parents and assigning paternity. The hybrids showed 22 markers that were absent in P. ciliata but were monomorphically present in all the hybrids, suggesting outcrossing and common paternity. Further, these 22 markers were found in all the P. maximowiczii genotypes confirming it as the male parent. These male-specific markers can be converted to SCAR markers and used for rapid screening of the P.ciliata × maximowiczii hybrids. The primer combination E-AAC × M-CAA was identified as most suitable for ascertaining true hybridity. AFLP proves to be a useful tool for screening of P. ciliata × maximowiczii hybrids at the early stages of development.Communicated by H.F. Liskens