R. K. Srivastava

Natural Product Inspired Diversity Oriented Synthesis of Tetrahydroquinoline Scaffolds as Antitubercular Agent

An efficient natural product inspired diversity oriented syn thesis of tetrahydroquinoline analogues has been developed using the natural carbohydrate derived solid acid catalyst via multicomponent aza-Diels-Alder reaction of imine (generated in situ from aromatic amine and aldehyde) with dienophile in acetonitrile in a diastereoselective manner. The use of water as solvent reverses the diastereoselectivity toward the cis isomer. Interestingly, tricyclic pyrano/furano benzopyran with cis diastereoselectivity is obtained when salicylaldehyde is used as an alternative of aromatic aldehyde under the same condition. These synthesized quinolines and benzopyrans analogues have been evaluated for their Antitubercular activity against M. tuberculosis H₃₇Ra, and M. tuberculosis H₃₇Rv, and some of the analogues shows better activity profile than their natural product analogues. The protocol is not only mild, efficient, ecofriendly, but also involves reusable and biodegradable catalyst and provides route for both the diastereoisomer.

Development of artificial neural-network-based models for the simulation of spring discharge

The present study demonstrates the application of artificial neural networks (ANNs) in predicting the weekly spring discharge. The study was based on the weekly spring discharge from a spring located near Ranichauri in Tehri Garhwal district of Uttarakhand, India. Five models were developed for predicting the spring discharge based on a weekly interval using rainfall, evaporation, temperature with a specified lag time. All models were developed both with one and two hidden layers. Each model was developed with many trials by selecting different network architectures and different number of hidden neurons; finally a best predicting model presented against each developed model. The models were trained with three different algorithms, that is, quick-propagation algorithm, batch backpropagation algorithm, and Levenberg-Marquardt algorithm using weekly data from 1999 to 2005. A best model for the simulation was selected from the three presented algorithms using the statistical criteria such as correlation coefficient (R), determination coefficient, orNash Sutcliffs efficiency (DC). Finally, optimized number of neurons were considered for the best model. Training and testing results revealed that the models were predicting the weekly spring discharge satisfactorily. Based on these criteria, ANN-based model results in better agreement for the computation of spring discharge. LMR models were also developed in the study, and they also gave good results, but, when compared with the ANN methodology, ANN resulted in better optimized values.

Monitoring Land Cover Changes in coastal tract of Odisha using Landsat ETM+ Imagery

Alteration of land cover takes place dramatically because of great forces of natural calamities. Qualitative and quantitative information about these changes are useful for sustainable management of natural resources. Especially coastal areas are prone to land coverage changes due to many reasons, among which natural calamities rank as one of the major factor. Odisha, being located in Eastern part of India, covering 480 km coastal tract is very susceptible to frequent natural catastrophes like cyclone and super cyclone. In this paper, land cover change dynamics were investigated by the combined use of satellite remote sensing and geographical information systems. The main objective of the study was to determine land-cover changes among land cover types in coastal areas of Kendrapara. Landsat ETM+ images of the year 2000 and 2006 were used to gather land cover change data of the coastal belt of Kendrapara district, Odisha. The images were classified using unsupervised classification and a post-classification comparison approach was used in change detection. The results show increase in agricultural areas and other vegetated areas but decrease in water bodies and soil and barren areas.

Ocimum as a Promising Commercial Crop

Basil, Ocimum Spp, (Family Labiatae), is a herbaceous, erect, annual important aromatic plant, which attains the height of about 80–100 cm. The leaves of the plant are dark green or yellowish green in colour. Flowering tops and leaves of plant yields essential oils, which are used in perfumery and pharmaceutical industries. Stems of the plant are often branched and bear leaves. Many species of basil are available in nature including Ocimum basilicum, Ocimum canum, Ocimum gratissimum and Ocimum sanctum (Sharma et al. in J Med Arom Plant Sci 18:512–522, 1996). Basil can be grown in wide ranges of soil like light loam and medium loam having good water holding capacity with a pH range of 5.0–8.30. The best crop rotation of basil is basil–chamomile–mint or basil–mustard–mint or basil–potato–mint in the subtropical region. It prefers mild climate with moderate temperature of about 27 °C for successful growth. Basil is propagated through seeds. The nursery is raised in the month of May, and the seedlings are transplanted in the main field in the month of June/July. Nursery-raised seedlings of 30 days’ age are planted with the spacing of 30–35 cm plant to plant and 45–50 cm row to row depending upon soil fertility. After planting of seedlings, irrigation is necessary. During the whole period of life, 2–3 weedings are required to minimize weed competition. In average fertile soil, 50 kg nitrogen, 40 kg phosphorus and 40 kg potash per ha are sufficient. Nitrogen is applied in three equal doses during the growth period of the plant. It takes about 85–90 days for maturity, when lower leaves start turning yellow and full blooming condition appears. Harvesting is done by sharp sickle. After harvesting and distillation, about 110 kg of oil is received from per hectare area. The present market rate of basil oil is Rs. 650 per kg (Essential oil Market Report 2014), and cost of cultivation is about Rs. 23,546 to per ha. A farmer can earn Rs. 47,954 per ha within a period of 100 days.

Determination of Acetaldehyde Content in Candesartan Cilexetil by HPLC

A sensitive, cost-effective, reproducible high-performance liquid chromatography method was developed and validated for quantitative determination of acetaldehyde in candesartan cilexetil using the concept of threshold of toxicological concern. Acetaldehyde is reacted with 2,4-dinitrophenylhydrazine to form a Schiff base product with an absorbing maximum at 364 nm. Effective chromatographic separation was achieved on an Inertsil ODS 3V, 250×4.6 mm, 5 µm column with a mobile phase of 40:60 v/v water and acetonitrile and at a flow rate of 1.0 ml/min. The column temperature was controlled at 25° and the injection volume was 30 µl. These conditions resolved the dinitrophenylhydrazine-acetaldehyde product with unreacted dinitrophenylhydrazine, the drug substances and related impurities, as well as diluent peak within 20 min. The retention time of dinitrophenylhydrazine-acetaldehyde product was approximately 10.6 min. The method was linear, accurate, precise, specific, rapid and found suitable for this analysis.

Dental fluorosis and oral health status of 13–15-Year-Old school children of Chikkaballapur District: A cross-sectional study

Introduction: The high prevalence, severity, and the crippling nature of oral diseases lead to significant absenteeism in schools and economic loss in the working population. Dental fluorosis is endemic in 15 states of India and Chikkaballapur district is one among them. Aim: To assess dental fluorosis and oral health status and in Chikkaballapur district among 13–15 years school going children. Materials and Methods: A cross-sectional study was conducted among 2400 school going children of 13–15-year-old in Chikkaballapur district. The data regarding the dental fluorosis were collected using the Thylstrup and Fejerskov index. The clinical examination for the oral health status was determined using the WHO Oral Assessment Form 1997. Proportions were compared using Chi-square test, and one-way analysis of variance was used to test the differences. Results: It was seen that the mean decayed, missing, and filled teeth was highest among the 13-year-old at 1.39. Bleeding on probing and calculus was highest among 15-year-old with 83.5% and 84.6%, respectively. The prevalence of dental fluorosis in Chikkaballapur district was found to be 41.1%. Conclusion: The oral health status of the individuals was poor, and the prevalence of fluorosis was high. There is a need to create awareness regarding oral health and fluorosis.

Effectiveness of two oral health education intervention strategies among 12-year-old school children in North Bengaluru: A field trial

Introduction: Oral hygiene practices are not taught as meticulously as general hygiene in schools. There is a dire need for effective and convenient oral health education program in schools. Aim: To assess the effectiveness of two different health education interventions in 12-year-old school children in Bengaluru. Materials and Methods: A field trial was conducted in two schools of North Bengaluru which were randomly selected and allotted to Group A (received oral health education from a class teacher, trained by a dental professional; n = 30) and Group B (received the same education from the dental professional; n = 33). Oral prophylaxis for both the groups was done at baseline. Assessment of oral hygiene was done for all the subjects using Silness and Loe plaque index and oral hygiene index-simplified (OHI-S) along with reinforcement of health education at 3, 6, and 12 weeks. An adapted version of the World Health Organization Oral Health Questionnaire for children was administered to the participants at the beginning and end of the study to assess the oral health knowledge and practice. Mann–Whitney U-test and t-test were used for comparing the mean scores of two groups. Results: A statistically significant difference was found between Group A and Group B in the plaque scores at all 3 follow-ups (P < 0.001) and in OHI-S scores last two follow-ups (P < 0.05). There was an increase in knowledge score postintervention for both groups which was significant; however only Group B be showed significant improvement in practice (P < 0.05). Conclusions: Oral health education conducted by the dentist was found to be more effective than that given by a trained teacher.