Anti-tuberculosis activity of selected medicinal plants against multi-drug resistant Mycobacterium tuberculosis isolates.

Background & objectives: Emergence of multi-drug resistant (MDR) and extensively-drug resistant (XDR) strains of Mycobacterium tuberculosis has further complicated the problem of tuberculosis (TB) control. Medicinal plants offer a hope for developing alternate medicines for the treatment of TB. The present study was done to evaluate in vitro anti-tubercular activity of five medicinal plants viz., Acalypha indica, Adhatoda vasica, Allium cepa, Allium sativum and Aloe vera. Methods: Aqueous extracts of leaves of A. indica, A. vasica, bulbs of A. cepa, cloves of A. sativum and pure gel of A. vera leaves, were tested in vitro for their activity against two MDR isolates (DKU-156 and JAL-1236), reference susceptible strain M. tuberculosis H37Rv as well as rapid grower mycobacterial pathogen M. fortuitum (TMC-1529) using Lowenstein Jensen (L-J) medium and colorimetric BacT/ALERT 3D system. Activity in L-J medium was evaluated by percentage inhibition which was calculated by mean reduction in number of colonies on extract containing as compared to extract free controls. Results: Extracts of all the five plants A. indica, A. vasica, A. cepa, A. sativum and A. vera exhibited anti-tuberculosis activity in L-J medium, the proportion of inhibition of these plants extract in respect mentioned above is 95, 32, 37, 72, 32 per cent, respectively for MDR isolate DKU-156 and 68, 86, 79, 72, 85 per cent, respectively for another MDR isolate JAL-1236, while for sensitive M. tuberculosis H37Rv, inhibition was found to be 68, 70, 35, 63 and 41 per cent, at 4 per cent v/v concentration in L-J medium. There was no inhibition against rapid grower M. fortuitum (TMC-1529). In BacT/ALERT also, extracts of these plants showed significant inhibition against M. tuberculosis. Interpretation & conclusions: Our findings showed that all these plants exhibited activity against MDR isolates of M. tuberculosis. While the anti-TB activity of A. vera, A. vasica and A. sativum against MDR isolates confirm earlier results, activity of the extracts of A. indica and A. cepa is reported for the first time. Further studies aimed at isolation and identification of active substances from the extracts which exhibited promising activities, need to be carried out.

Identification of environmental mycobacteria isolated from Agra, north India by conventional & molecular approaches.

Background & objectives: Several environmental mycobacteria have been shown to be important human pathogens linked to immunomodulation especially in relation to effect on vaccination. Hence identification of mycobacteria to the species level is not only relevant to patient management but also to understand epidemiology of mycobacterial diseases and effect on vaccination. We undertook this study to assess the usefulness of various conventional and molecular methods in identification of environmental mycobacterial species from Agra, north India. Methods: One hundred nineteen isolates of environmental mycobacteria were grown from 291 (116 soil and 175 water) samples. These isolates were identified by standard biochemical tests, and a simple, rapid and cost-effective in-house developed gene amplification restriction analysis targeting 16S-23S rRNA spacer and flanking region and 16S rRNA sequencing. Results: Biochemical tests could clearly identify only 68.1 per cent (81/119) of isolates to species level. An in-house developed gene amplification - restriction analysis method could confirm the identity of 102 of 119 (85.7%) isolates and the remaining 17 isolates (14.3%) were confirmed by 16S rRNA sequencing also. These 119 environmental mycobacterial isolates, included several potentially pathogenic species such as M. fortuitum, M. chelonae, M. avium, M. marinum, M. manitobense, M. kansasii and others belonged to nonpathogenic species, M. terrae, M. smegmatis and M. flavescens. M. chelonae was isolated from water samples only whereas M. fortuitum was isolated from both water as well as soil samples. Interpretation & conclusion: The in-house developed gene amplification restriction analysis method though failed to accurately identify 14.3 per cent of isolates, facilitated rapid differentiation of most of environmental mycobacteria including potential pathogens from this area and thus would have diagnostic potential in cases with NTM infections. This combination strategy using PCR-RFLP and 16S rRNA sequencing may be useful for characterization of mycobacteria from similar environmental settings from other parts of world.

Impact of environmental changes on the reproductive biology in Pyrostegia venusta Presl.

Local environment (temperature and relative humidity) affects reproductive biology in Pyrostegia venusta (Bignoniaceae) growing at Agra and Mysore. At Agra, the species flowers profusely during December to March, but fails to bear fruits. At Mysore, on the other hand it flowers during November to February and produces well developed fruits with winged seeds. This species, growing at two places, exhibited differences in their pollen fertility and in vivo pollen germination. Pollen fertility at Agra and Mysore was 27.55 and 80-90%, respectively. The in vivo pollen germination on stigmatic surface was only 3-4% at Agra, but 85-95% at Mysore. The flowers at Agra also exhibited heterostyly and increased number of stamens and stigmatic lobes. The significantly low and wide ranged temperature (4.5-33.8oC) and between 23-98% RH during the flowering period at Agra could be the cause for reduced in pollen fertility, floral polymorphism and inhibition of pollen germination on the stigmatic surface and fruitlessness. At Mysore, where temperature ranges between 20.2-33.5oC and RH varies from 33-75% profuse fruiting takes place. The study shows a direct control of environment over the process of reproduction.

Growth and periodicity of cyanobacterial bloom in a polluted pond of Agra city.

Periodical changes in physico-chemical properties and cyanophycean bloom in a pond ofAgra city during the year 2005 and 2006 were studied. It was recorded that the pond water was polluted throughout the study period and this was closely associated with Cyanobacterial bloom. During summer (March to June), the pond water was highly polluted, as it was rich in various nutrients and phosphates in particular. The pH of pond water was high with low DO and this was associated with the highest peak of water bloom. On the other hand, during winter (November to January), the bloom was at its lowest. The quantity of various nutrients in the pond water was low and the pH was also low but DO was high. Bloom consisted of eighteen members of Cyanophyceae of which Oscillatoria limosa, O. formosa, O. splendida, Anabeana iyengarii, Microcystis arruginosa and Nostoc muscorum were observed throughout the year. On the other hand, Oscillatoria agardhi, and O. tenuis were found only in winters, while O. annae in rainy season only. Similarly, Oscillatoria brevis, Anabaena flosaquae, Aphanizomenon sp. and Lyngybea birgei were found in abundance in summer.

Assessment of bio-medical waste management in three apex government hospitals of Agra.

Waste management practices in three apex government hospitals of Agra viz., Sarojini Naidu Medical College, Lady Lyall Maternity Hospital and District Hospital were studied during January 2004-January 2005. Data were collected with the help of (i) personal observations of the waste treatment and disposal practices and (ii) assessment of knowledge, attitude and practices of working personnel with the help of questionnaires. The results obtained indicated lack of knowledge and awareness regarding legislations on bio-medical waste management even among qualified hospital personnel. None of these hospitals were equipped with higher technological options e.g. incinerator autoclave, microwave and had no facilities to treat the liquid waste generated inside the hospital. It is concluded that generation and implementation of a waste management policy institutiona/organizational set up, training and motivation must be given paramount importance to meet the current needs and standards of bio-medical waste management in these hospitals.

Seasonal phytoplanktonic diversity of Kitham lake, Agra.

Two years (Jan. 2000 - Dec. 2001) data on the seasonal studies of phytoplanktonic diversity of Kitham lake (Sur Sarovar) Agra revealed the presence of 73 algal species. A limited number of these were recorded throughout the year, while others were distributed in different seasons mainly in winter and summer seasons. During winters, Chlorophyceae was the most dominant group followed by Bacillariophyceae. On the other hand, Cyanophyceae and Euglenophyceae were the most dominant during summers. Certain species e.g. Pandorina morum, Pediastrum tetras, Gonium sp., Chlorella vulgaris, Scendesmus quadricauda, Oedogonium cardiocum, Synedra ulna, Oscillatoria agardhii and Euglena gracillis were recorded throughout the year. Chlorella, Stigeoclonium, Pandorina, Micratinium, Oscillatoria, Anacystis, Nitzschia and Cymbella were found to be good indicators of water pollution.

Impact of air pollution on floral morphology of Cassia siamea Lamk.

Cassia siamea plants growing at two different sites (polluted and non-polluted) on two important roads of Agra city exhibited significant differences in their flowering phenology and floral morphology. The flowering in plants growing at polluted site is delayed and there was a marked reduction in flowering density, flowering period, size of floral parts, pollen fertility, fruit and seed-set. SEM observations revealed the presence of well developed glandular structures and reduction in the number and size of large stomata on the anther surface at polluted site. These changes were found to be closely associated with the extent of air pollution caused mainly by significant in the number of automobiles.

Role of phenolics and boron in reproductive success in seasonally transient sterile Tecoma stans L.

Quantitative and qualitative analysis of phenolics and boron in stigma of transient sterile Tecoma stans L. during seedless (May-July), partially seedbearing (August-November, April) and seedbearing periods (December-March) was made. UV absorption profile of stigmatic exudates indicated the presence of simple phenolics. Total phenolics were higher in stigma during seedless period. Thin layer chromatographic analysis of stigmatic extracts exhibited only three principal spots. Mass spectrophotometry showed the presence of derivatives of cinnamic acid, namely, caffeic acid in these spots. Quantity of boron in stigma during seedless period was lowest but the difference with other periods was not significant. It was suggested that the accumulation of higher quantity of caffeic acid in the stigma during seedless period due to high temperature (40 degrees-45 degrees C) could lead to inhibition of pollen germination in vivo, thereby rendering the plants seedless. This was confirmed by inhibition of in vitro pollen germination in the basal medium containing higher quantity of caffeic acid.

Sample size for collecting germplasms--a polyploid model with mixed mating system.

The present paper discusses a general expression for determining the minimum sample size (plants) for a given number of seeds or vice versa for capturing multiple allelic diversity. The model considers sampling from a large 2 k-ploid population under a broad range of mating systems. Numerous expressions/results developed for germplasm collection/regeneration for diploid populations by earlier workers can be directly deduced from our general expression by assigning appropriate values of the corresponding parameters. A seed factor which influences the plant sample size has also been isolated to aid the collectors in selecting the appropriate combination of number of plants and seeds per plant. When genotypic multiplicity of seeds is taken into consideration, a sample size of even less than 172 plants can conserve diversity of 20 alleles from 50,000 polymorphic loci with a very large probability of conservation (0.9999) in most of the cases.

A general model for sample size determination for collecting germplasm.

The paper develops a general model for determining the minimum sample size for collecting germplasm for genetic conservation with an overall objective of retaining at least one copy of each allele with preassigned probability. It considers sampling from a large heterogeneous 2k-ploid population under a broad range of mating systems leading to a general formula applicable to a fairly large number of populations. It is found that the sample size decreases as ploidy levels increase, but increases with the increase in inbreeding. Under exclusive selfing the sample size is the same, irrespective of the ploidy level, when other parameters are held constant. Minimum sample sizes obtained for diploids by this general formula agree with those already reported by earlier workers. The model confirms the conservative characteristics of genetic variability of polysomic inheritance under chromosomal segregation.