Kamal Rai Aneja

Synthesis and biological evaluation of some pyrazolylpyrazolines as anti-inflammatory-antimicrobial agents

A new series of pyrazolylpyrazolines (5a-k) was synthesized by the reaction of appropriate chalcones (3a-k) with 4-hydrazinobenzenesulfonamide hydrochloride (4) in ethanol. All the newly synthesized target compounds (5a-k) were screened for their anti-inflammatory activity using carrageenan-induced rat paw edema assay. Compounds 5g and 5j showed pronounced anti-inflammatory activity comparable to the reference standard nimesulide, whereas, compounds 5b, 5d and 5h displayed good anti-inflammatory activity. Additionally, the synthesized compounds were evaluated for their in vitro antimicrobial activity against two Gram-positive bacteria and two Gram-negative bacteria. Four compounds 5c, 5h-5j showed good broad spectrum activity against all the tested Gram-positive and Gram-negative bacterial strains. Compound 5j could be identified as the most biologically active member within this study with an interesting dual anti-inflammatory and antibacterial profile.

Fungal infection of the ear: a common problem in the north eastern part of Haryana.

OBJECTIVE The aim of this study was to determine the prevalence of fungal agents, sex distribution and predisposing factors involved in otomycosis. METHODS Samples from the 118 clinically suspected patients of otomycosis were collected between January 2008 and February 2009, with an age group of 6 and 75 years. Mycological examination of all the samples was done to isolate the fungal agents involved in otomycosis. RESULTS Mycological examination has revealed the confirmation of fungal otomycosis in 78% of the suspected patients. Pruritus has been found as the most common symptom. The major predisposing factors responsible for the otomycosis have been found as the wearing of traditional customary clothes followed by itching on other body parts and swimming. It has been found to be more prevalent in females than males in the age group of 31-40 years, higher incidence occurring in the rainy season. The fungi involved in otomycosis belonged to Aspergillus niger, A. flavus, A. fumigatus, A. luchuensis, A. terreus, Candida albicans and Penicillium sp. Of these, A. niger followed by A. flavus were the dominant fungi. Aspergillus luchuensis as the cause of otomycosis has been reported for the first time. CONCLUSION Finally we can say higher incidence of otomycosis may be due to high degree of humidity, warm and dusty environment. So, keeping in view the high prevalence of otomycosis in India, critical diagnosis of the causative agent by employing aseptic and proper culture techniques and susceptibility testing for proper treatment of this disease is the need of the hour.

Essential oil composition and antibacterial studies of Vitex negundo linn. extracts

Essential oils from fresh leaves, flowers and dried fruits of Vitex negundo were obtained by hydrodistillation. Using Soxhlet extractor five successive extracts from dried and powdered leaves were also taken. The chemical constituents of essential oil of leaves, flowers and dried fruits were analyzed by GC-FID and GC/MS techniques. Main constituents identified in leaves oil were δ-guaiene, carryophyllene epoxide and ethyl-hexadecenoate; in flowers oil - α-selinene, germacren-4-ol, carryophyllene epoxide and (E)-nerolidol while fruit oil showed β-selinene, α-cedrene, germacrene D and hexadecanoic acid as the main constituents. β-Caryophyllene was only the constituent identified as common to all three oils. α-Guaiene and guaia-3,7-diene were identified as common constituents in leaf and dried fruit oil while leaf and flower oils showed p -cymene, valencene, caryophyllene epoxide and (E)-nerolidol as common constituent. All the essential oils and successive extracts were evaluated for antibacterial potential against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa bacterial strains. Each of the essential oils and extracts were found to give promising results against B. subtilis and E. coli. Ethyl acetate and ethanol extracts showed prominent antibacterial activity against all the tested strains. Fruits and leaves oil were found to be most active against E. coli and S. aureus, respectively. Only flowers oil was found to be active against P. aeruginosa.

Ultrasound promoted one pot synthesis of novel fluorescent triazolyl spirocyclic oxindoles using DBU based task specific ionic liquids and their antimicrobial activity.

Spirocyclic oxindoles and triazolyl derivatives posses remarkable biological activities. In present work, we have described an efficient one pot four-component domino reaction of 1-(prop-2-ynyl)indoline-2,3-dione, cyclic 1,3-diketones, malononitrile and various aryl azides in DBU based ionic liquids [DBU-H]OAc and [DBU-Bu]OH under ultrasonic irradiation for the construction of heterocycles, comprising spiro-oxindole, 2-amino-4H-pyran, and 1,2,3-triazoles substructures. The antimicrobial activity of all compounds has been investigated against six microbial strains. All compounds showed good antimicrobial activity. All newly synthesized compounds exhibit fluorescence in methanol with large stoke shift.

Hypervalent iodine(III) mediated synthesis of novel unsymmetrical 2,5-disubstituted 1,3,4-oxadiazoles as antibacterial and antifungal agents.

A series of novel 2,5-disubstituted 1,3,4-oxadiazoles 4 have been conveniently synthesized by oxidative cyclization of pyrazolylaldehyde N-acylhydrazones 3 promoted by iodobenzene diacetate under mild conditions (11 examples, up to 92% isolated yields). All the eleven compounds were tested in vitro for their antibacterial activity against gram-positive bacteria namely, Staphylococcus aureus, Bacillus subtilis and two gram-negative bacteria namely, Escherichia coli and Pseudomonas aeruginosa. All the synthesized compounds were also tested for their inhibitory action against two strains of fungus.

Emerging Preservation Techniques for Controlling Spoilage and Pathogenic Microorganisms in Fruit Juices

Fruit juices are important commodities in the global market providing vast possibilities for new value added products to meet consumer demand for convenience, nutrition, and health. Fruit juices are spoiled primarily due to proliferation of acid tolerant and osmophilic microflora. There is also risk of food borne microbial infections which is associated with the consumption of fruit juices. In order to reduce the incidence of outbreaks, fruit juices are preserved by various techniques. Thermal pasteurization is used commercially by fruit juice industries for the preservation of fruit juices but results in losses of essential nutrients and changes in physicochemical and organoleptic properties. Nonthermal pasteurization methods such as high hydrostatic pressure, pulsed electric field, and ultrasound and irradiations have also been employed in fruit juices to overcome the negative effects of thermal pasteurization. Some of these techniques have already been commercialized. Some are still in research or pilot scale. Apart from these emerging techniques, preservatives from natural sources have also shown considerable promise for use in some food products. In this review article, spoilage, pathogenic microflora, and food borne outbreaks associated with fruit juices of last two decades are given in one section. In other sections various prevention methods to control the growth of spoilage and pathogenic microflora to increase the shelf life of fruit juices are discussed.

A facile iodine(III)-mediated synthesis of 3-(3-aryl-1-phenyl-1H-pyrazol-4-yl)-[1,2,4]triazolo[4,3-a]pyridines via oxidation of 2-((3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-1-(pyridin-2-yl)hydrazines and their antimicrobial evaluations

Background Fused heterocyclic 1,2,4-triazoles have acquired much importance because of their interesting biological properties. Although a number of methods have been reported in the literature which includes oxidation with phosphorus oxychloride, lead tetraacetate, bromine, etc., hypervalent iodine reagents have emerged as reagents of choice for various synthetically useful transformations due to their low toxicity, ready availability and ease of handling. Results A series of new 3-(3-aryl-1-phenyl-1H-pyrazol-4-yl)-[1,2,4]triazolo[4,3-a]pyridines 4 has been conveniently synthesized by oxidative cyclization of 2-(3-aryl-1-phenyl-1H-pyrazol-4-yl)methylene)-1-(pyridin-2-yl)hydrazines 3 promoted with iodobenzene diacetate under mild conditions (up to 90% isolated yields). All the new compounds were tested in vitro for their antimicrobial activity. Conclusions Iodine(III)-mediated oxidative approach has offered an easy access to new 3-(3-aryl-1-phenyl-1H-pyrazol-4-yl)-[1,2,4]triazolo[4,3-a]pyridines 4. The antibacterial and antifungal activities of newly synthesized compounds have proved them potent antimicrobial agents.

Synthesis and biological evaluation of some 4-functionalized-pyrazoles as antimicrobial agents

1,3-Diaryl-4-formylpyrazoles 8 bearing benzenesulfonamide moiety at position-1 were synthesized as important intermediates following Vilsmeier-Haack strategy. Aldehyde moiety of 4-formylpyrazole was then converted into carboxylic acid 9, cyano 10 and carbothioamide 11 using established procedures. Out of these 4-functionalized pyrazoles, pyrazole-4-carboxylic acids 9 and carbothioamides 11 were evaluated for their in vitro antibacterial activity against four pathogenic bacterial strains namely, Staphylococcus aureus, Bacillus subtilis (Gram-positive), Escherichia coli, Pseudomonas aeruginosa (Gram-negative), and in vitro antifungal activity against two pathogenic fungal strains namely, Aspergillus niger and Aspergillus flavus. Three tested compounds, 9e, 11b and 11f exhibited moderate antibacterial activity against Gram-positive bacteria and 9g showed moderate antifungal activity against the tested fungi. However, none of the compounds showed any activity against Gram-negative bacteria.

Microbes Associated with Freshly Prepared Juices of Citrus and Carrots

Fruit juices are popular drinks as they contain antioxidants, vitamins, and minerals that are essential for human being and play important role in the prevention of heart diseases, cancer, and diabetes. They contain essential nutrients which support the growth of acid tolerant bacteria, yeasts, and moulds. In the present study, we have conducted a microbiological examination of freshly prepared juices (sweet lime, orange, and carrot) by serial dilution agar plate technique. A total of 30 juice samples were examined for their microbiological quality. Twenty-five microbial species including 9 bacterial isolates, 5 yeast isolates, and 11 mould isolates were isolated from juices. Yeasts and moulds were the main cause of spoilage of juices. Aspergillus flavus and Rhodotorula mucilaginosa were observed in the maximum number of juice samples. Among bacteria Bacillus cereus and Serratia were dominant. Escherichia coli and Staphylococcus aureus were detected in few samples. Candida sp., Curvularia, Colletotrichum, and Acetobacter were observed only in citrus juice samples. Alternaria, Aspergillus terreus, A. niger, Cladosporium, and Fusarium were also observed in tested juice samples. Some of the microorganisms detected in these juice samples can cause disease in human beings, so there is need for some guidelines that can improve the quality of fruit juices.

Macrocyclic metal complexes derived from 2,6-diaminopyridine and isatin with their antibacterial and spectroscopic studies

Condensation reaction of 2,6-diaminopyridine with isatin in the presence of divalent metal ions results in the formation of the macrocyclic complexes of the type [M(C(26)H(16)N(8))X(2)], where M=Co(II), Ni(II), Cu(II), Zn(II), Cd(II) and X=Cl(-), NO(3)(-), CH(3)COO(-). The complexes have been characterized with the aid of elemental analyses, conductance measurements, electronic, NMR, infrared and EPR spectral studies. The lower values of molar conductance indicate them to be non-electrolytes. On the basis of these studies, a six coordinate distorted octahedral geometry in which four nitrogen atoms are suitably placed for coordination towards metal ion, has been proposed for all the complexes. The complexes were tested for their in vitro antibacterial activity. Some of the complexes showed good antibacterial activities against some selected bacterial strains.