Synthesis and SAR study of novel anticancer and antimicrobial naphthoquinone amide derivatives.

A series of novel naphthoquinone amide derivatives of the bioactive quinones, plumbagin, juglone, menadione and lawsone, with various amino acids were synthesized. The compounds were characterized by (1)H NMR, (13)C NMR, Mass, IR and elemental analysis. All the compounds were evaluated for their anticancer activity against HeLa and SAS cancer cell lines and 3D-QSAR indicated the presence of electron donating group near sulphur enhanced the activity against HeLa cells. Among the derivatives synthesized, compounds 11f, 10a, 10b and 10g were the most active with IC50 values of 16, 12, 14 and 24.5 µM, respectively. The analogues were also screened for antimicrobial activity against two human bacterial pathogens, the Gram-positive Methicillin resistant Staphylococcus aureus (MRSA) and the Gram-negative Pseudomonas aeruginosa and a human yeast pathogen, Fluconazole resistant Candida albicans (FRCA). Among the synthesized compounds, 8g, 10g and 11g exhibited maximum antibacterial activity towards MRSA and antifungal activity against FRCA in well diffusion method.

Synthesis of 7-oxabicyclo[2.2.1]hept-5-en-2-yl derivatives and their screening for antimicrobial and antioxidant properties.

Novel 7-oxabicyclo[2.2.1]hept-5-en-2-yl derivatives have been synthesized using boron trifluoride diethyl etherate catalyzed Diels-Alder reaction. This method presents considerable synthetic advantages in terms of high atom economy, mild reaction condition and good yields. The synthesized compounds have been screened for their antibacterial and antioxidant activities.

Synthesis of quinoline derivatives for fluorescent imaging certain bacteria.

Highly fluorescent quinoline derivatives were synthesized using Sc(OTf)(3) catalyzed imino Diels-Alder reaction. Both the aromatic and their analogous tetradehydroquinoline derivatives were explored for the detection of bacteria using fluorescent imaging studies. Surprisingly the aromatic quinoline derivatives show a remarkable fluorescent response that can be useful in the detection of both gram positive and gram negative bacteria even at a concentration in the range of 0.078 mM.

Synthesis of novel beta-lactam fused spiroisoxazolidine chromanones and tetralones as potent antimicrobial agent for human and plant pathogens.

Synthesis of novel beta-lactam fused spiroisoxazolidine chromanones and tetralones ring systems has been achieved by intermolecular 1,3-dipolar cycloaddition reaction of bicyclic nitrone with unusual dipolarophiles, arylidene chromanones/tetralones under different reaction conditions. The synthesized compounds were evaluated for antimicrobial activities. It was observed that two of the synthesized compounds exhibited relatively good antibacterial and antifungal activities.

Characterization of a thermostable alkaline protease produced by marine Streptomyces fungicidicus MML1614.

Totally 191 different marine actinomycetes were isolated from 256 different marine samples collected from the Bay of Bengal and its associated Pulicat lake and Pichavaram mangrove, India. Among them, 157 produced caseinase, 113 produced gelatinase and 108 produced both the protease enzymes. An isolate coded as MML1614 was selected for further study as it exhibited high proteolytic activity. The MML1614 was identified as Streptomyces fungicidicus based on polyphasic taxonomical approach including 16S rRNA sequence analysis. The culture conditions were standardized for the growth and protease production in S. fungicidicus MML1614. The protease was isolated from a 6-day-old culture filtrate of S. fungicidicus MML1614 and partially purified up to 4.5-fold. The protease was optimally active at pH 9 and 40 degrees C and it was stable up to pH 11 and 60 degrees C. PMSF and NaCl inhibited the enzyme activity up to 22 and 11%, respectively. The partially purified protease removed the blood stain more effectively when combined with different detergents than the detergents alone.

Green synthesis of silver-nanoparticles from Annona reticulata leaves aqueous extract and its mosquito larvicidal and anti-microbial activity on human pathogens.

Silver nanoparticles play a important role in controlling mosquito population as well as multi drug resistant pathogens without causing much harm to humans. In the present study was focused on green synthesis of silver nanoparticles against dengue causing vector (Aedes aegypti) and pathogens affecting humans. The synthesized silver nanoparticle was confirmed using UV- absorption spectrum range obtained at 416 nm, XRD, FTIR and HR-TEM analysis were used to determine the silver nanoparticle morphology and size with ∼6.48 ± 1.2-8.13 ± 0.18 nm and face centered cubic structure. The synthesized silver nanoparticles were exposed to fourth instar larvae of A. aegypti with different concentration (3-20 µg/mL) for 24 h and its elicit maximum mortality (100%) at their final concentration of 20 µg/mL and it's LC50 value was 4.43 µg/mL and LC90 value was 13.96 µg/mL, respectively. The minimum inhibitory activities of the tested pathogens were 125, 31.25, 62.5, 62.6 and 62.5 µg/mL for the Bacillus cereus, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli and Candida albicans respectively. Further, the synthesized silver nanoparticle shows a potent antimicrobial activity against all tested pathogens. Moreover the effect of silver nanoparticle against Red Blood Cells belonging to 'O' positive blood group were tested and does not cause higher hemolysis to the cells even at the highest concentration. Based on these finding, we strongly suggested that face centered cubic structured A. reticulata AgNPs is an eco-friendly and potent bio-medical agent and can be apply in wide range of application an alternative chemically synthesized metal nanoparticle.

Exploring DNA quantity and quality from raw materials to botanical extracts.

OBJECTIVES: The aim of this study was to explore the variability in DNA quality and quantity along a gradient of industrial processing of botanical ingredients from raw materials to extracts. METHODS: A data matrix was assembled for 1242 botanical ingredient samples along a gradient of industrial processing commonly used in the Natural Health Product (NHP) industry. Multivariate statistics was used to explore dependant variables for quality and quantity. The success of attaining a positive DNA test result along a gradient of industrial processing was compared among four biotechnologies: DNA barcoding, NGS, Sanger sequencing and qPCR. RESULTS: There was considerable variance in DNA quality and quantity among the samples, which could be interpreted along a gradient from raw materials with greater quantities (50-120 ng/µL) of DNA and longer DNA (400-500bp) sequences to extracts, which were characterized by lower quantities (0.1-10.0 ng/µL) and short fragments (50-150bp). CONCLUSIONS: Targeted molecular diagnostic tests for species identity can be used in the NHP industry for raw and processed samples. Non-targeted tests or the use of NGS for any identity test needs considerable research and development and must be validated before it can be used in commercial operations as these methods are subject to considerable risk of false negative and positive results. Proper use of these tools can be used to ensure ingredient authenticity, and to avert adulteration, and contamination with plants that are a health concern. Lastly these tools can be used to prevent the exploitation of rare herbal species and the harvesting of native biodiversity for commercial purposes.

Synthesis of novel spiropyrrolizidines as potent antimicrobial agents for human and plant pathogens.

A series of novel dispirooxindolopyrrolizidine derivatives have been synthesized through 1,3-dipolar cycloaddition reaction of azomethine ylide generated from proline and isatin with the dipolarophile (E)-2-arylidine-1-keto carbazoles. The synthesized cycloadducts were evaluated for antimicrobial activities. Compounds 7d and 7e showed relatively good antibacterial and antifungal activities.

Synthesis of some novel imidazole-based dicationic carbazolophanes as potential antibacterials.

Synthesis of fluorescent imidazole-based dicationic carbazolophanes incorporating various spacer units is described. Interestingly, the cyclophanes 2a and 5a incorporating a pyridine moiety exhibited superior antibacterial activity against most of the pathogenic bacteria in the tested concentrations as compared to the other cyclophanes as well as the test control, benzalkonium chloride (BAC), cetylpyridinium chloride (CPC) and tetracycline.

Morinda pubescens JE Smith (Morinda tinctoria Roxb) fruit extract accelerates wound healing in rats.

This study investigated the wound healing properties of the chloroform extract of Morinda pubescens fruit in rats. Topical application of M. pubescens fruit extract at 20 mg/mL and 10 mg/mL concentrations appreciably accelerated wound healing in rats compared with controls. Complete wound contraction was achieved, and fresh hair began to grow in the entire wounded area within 15 days in animals treated with the 20 mg/mL chloroform fruit extract of M. pubescens compared with only 60% contraction without hair growth in control rats.

Optical Fiber-Based Steady State and Fluorescence Lifetime Spectroscopy for Rapid Identification and Classification of Bacterial Pathogens Directly from Colonies on Agar Plates.

Fluorescence spectroscopy was examined as a potential technique for identification and classification of bacterial pathogens. Colonies of Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, and Klebsiella pneumoniae on agar plates were measured directly using a laboratory spectrofluorimeter coupled with optical fiber. Steady state fluorescence spectra were collected following excitation at 280 nm (tryptophan) and 380 nm (NADH). Results showed that fluorescence lifetime decays of tryptophan at 280 nm excitation from the four organisms were best described with triexponential fit and it reveals the existence of different protein conformation. The emission spectroscopy of the four bacteria at 380 nm excitation (NADH) provided better classification (100% of original grouped cases correctly classified and 98.1% of cross-validated grouped cases correctly classified) than that of 280 nm excitation (tryptophan). Our results demonstrated that optical fiber-based fluorescence identification and classification of bacteria is rapid, easy to perform, and of low cost compared to standard methods.

Structural and functional studies on urease from pigeon pea (Cajanus cajan).

Urease is an enzyme that catalyzes the hydrolysis of urea, forming ammonia and carbon dioxide, and is found in plants, microorganisms and invertebrates. Although plant and bacterial ureases are closely related at amino acid and at the structural level, the insecticidal activity is seen only in the plant ureases. In contrast, both plant and bacterial ureases exhibit antifungal activity. These two biological properties are independent of its ureolytic activity. However, till date the mechanism(s) behind the insecticidal and fungicidal activity of ureases are not clearly understood. Here we report the crystal structure of pigeon pea urease (PPU, Cajanus cajan) which is the second structure from the plant source. We have deduced the amino acid sequence of PPU and also report here studies on its stability, insecticidal and antifungal activity. PPU exhibits cellulase activity. Based on the structural analysis of PPU and docking studies with cellopentoase we propose a possible mechanism of antifungal activity of urease.

Synthesis and antimicrobial activity of some novel dicationic sulphonophanes.

The synthesis of some novel imidazole-based dicationic sulfonophanes incorporating various spacer units is described. All the sulphonophanes exhibit good antibacterial and antifungal activity against five bacterial strains Bacillus subtilis, Staphylococcus aureus, Vibrio cholera, Escherichia coli, Proteus vulgaris and human pathogenic fungus Candida albicans.

Regioselective synthesis and antimicrobial screening of novel ketocarbazolodispiropyrrolidine derivatives.

A series of novel dispiropyrrolidine derivatives have been synthesized through 1,3-dipolar cycloaddition reaction of azomethine ylide generated from sarcosin and di/tri ketone with the dipolarophile (E)-2-arylidine-1-keto-carbazoles. The cycloadducts ketocarbazalo spiro N-methyl pyrrolidines showed the most interesting antimicrobial activity at lower concentration.

Synthesis of novel carbazole based macrocyclic amides as potential antimicrobial agents.

A series of carbazole based macrocyclic diamides with thia and oxy linkages have been synthesized and the inhibitory activity of the cyclophane amides against human pathogenic bacteria and plant pathogenic fungi are documented. (S)-1,10-Bi-2-naphthol [(S)-BINOL] based chiral carbazolophane amide emerged as the most interesting compound in this series exhibiting excellent antibacterial and antifungal activities.

Synthesis, characterization and electrochemistry of 4'-functionalized 2,2':6',2''-terpyridine ruthenium(II) complexes and their biological activity.

The synthesis and characterization of Ru(II) terpyridine complexes derived from 4'-functionalized 2,2':6',2''-terpyridine ligands by a multi step procedure have been described. The complexes are redox-active, showing both metal-centred (oxidation) and ligand-centred (reduction) processes. The antibacterial and antifungal activity of the synthesized ruthenium(II) complexes [Ru(attpy)2](PF6)2 (attpy = 4'-(4-acryloyloxymethylphenyl)-2,2':6',2''-terpyridine); [Ru(mttpy)2](PF6)2 (mttpy = 4'-(4-methacryloyloxymethylphenyl)-2,2':6',2''- terpyridine); [Ru(mttpy)(MeOPhttpy)](PF6)2 (MeOPhttpy = 4'-(4-methoxyphenyl)-2,2':6',2''-terpyridine); and [Ru(mttpy)(ttpy)](PF6)2 (ttpy = 4'-(4-methylphenyl)-2,2':6',2''-terpyridine) were tested against four human pathogens (Proteus vulgaris, Proteus mirabilis, Pseudomonas aeruginosa and Escherichia coli) and five plant pathogens (Curvularia lunata, Fusarium oxysporum, Fusarium udum, Macrophomina phaseolina and Rhizoctonia solani) by the well diffusion method and MIC values of the complexes are reported. A biological study of the complexes indicated that the complexes [Ru(mttpy)2](PF6)2 and [Ru(mttpy)(MeOPhttpy)](PF6)2 exhibit very good activity against most of the test pathogens and their activity is better than those of some of the commercially available antibiotics like tetracycline and the fungicide carbendazim.

Synthesis and antibacterial activity of some novel chiral fluorophoric biscyclic macrocycles.

Synthesis of chiral permanent fluorophoric biscyclic macrocycles incorporating anthraquinone and (S)-BINOL core is described. Interestingly, the biscyclic macrocycle 1 exhibited remarkable antibacterial activity against most of the pathogenic bacteria in the tested concentrations as compared to the other three compounds 2, 14 and 17 as well as the test control, tetracycline. Further biscyclophanes 1 and 2 exhibited permanent fluorescence sensing property even under highly acidic conditions.

Synthesis and anti-microbial activity of pyrazolylbisindoles--promising anti-fungal compounds.

A series of pyrazolylbisindole derivatives have been synthesized by reacting substituted pyrazole aldehydes with substituted indoles using phosphotungstic acid, a Keggin type heteropoly acid as catalyst. The synthesized pyrazolylbisindoles were evaluated for anti-microbial activities. The effect of pyrazolylbisindoles on the mycelial growth of plant pathogenic fungi is revealed. Entries 3c and 3d emerged as the most interesting compounds in this series exhibiting excellent anti-fungal activity.

Design, synthesis and anti-microbial activity of 1H-pyrazole carboxylates.

In a SAR study, we have synthesized a few 1H-pyrazole carboxylate related microbicides using Vilsmeier reagent. The anti-microbial screening results of 1H-pyrazole-3-carboxylate are reported here for the first time. The effect of 1H-pyrazole carboxylates on the mycelial growth of plant pathogenic fungi is revealed. The first X-ray structure in the family of microbicidal 1H-pyrazole-4-carboxylates is presented.