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Drought is an abiotic stress which causes huge economic losses in agriculture. Silicon is considered the best element which plays a key role in inducing drought mitigation properties. Silicate solubilizing bacterial strains were evaluated for their survivability in the low water activity potential. Bacillus tequilensis SKSSB09 showed high survivability at 40% polyethylene glycol 6000 concentration i.e. -1.76 MPa. ACC deaminase activity of the silicate solubilizing bacterial strains was assessed, among which B. tequilensis SKSSB09 showed ACC deaminase production in Dworkin and Foster minimal media. In–planta studies showed the survivability of maize plants till 23 days without water. Silicon deposition in the maize leaves showed 0.0384±0.0021μg/g. The leaf membrane stability index of the inoculated plants showed 72.2 ±3.8% which also correlates with the epicuticular wax content (2.4±0.56 mg/g). Proline content plays a key role in enhancing drought tolerance in plants. The inoculated plants showed high proline content (39.8±3.7 μg/g) which plays a key role in maintaining the cell sap and increasing the photosynthetic rate. Scanning electron microscopic studies revealed the deposition of silicon in the leaves and the formation of sunken stomata which reduces the transpiration rate. Based on the above results, Bacillus tequilensis SKSSB09 can be used as a plant growth-promoting rhizobacterial inoculant during drought conditions.

Natural colorants have emanated as a significant substitute to highly toxic synthetic dyes. The present study highlights the dyeing efficiency of violet pigment produced from Chromobacterium violaceum PDF23. A halophilic bacterium C. violaceum PDF23 produce violet pigments were isolated from the Great Salt Lake situated in Chennai, India. Based on morphology and 16S rRNA gene sequencing, a halophilic bacterium was identified as C. violaceum PDF23. The violet dye from C. violaceum PDF23 exhibited antimicrobial efficacy against S. aureus, B. subtilis, E. coli, P. aeruginosa, and C. albicans. The violet pigment exhibited radical scavenging potential with IC50 value of 14.40 mu g/mL. The dye ability of colorant was evaluated using mordants on two distinct fabrics, i.e., silk satin and cotton, and colorfastness measurements were recorded. The CIE L*a*b* qualities of the dyed fabrics were assessed, as well as their colorfastness quality. The current research findings suggest that violet pigment has potent antimicrobial and antioxidant activity and it could be used as alternative to synthetic dye in the textile industry., Sathyabama Institute of Science and Technology, Chennai; Deanship of Scientific Research, Vice Presidency for Graduate Studies and Scientific Research, King Faisal University, Saudi Arabia [GRANT1079]; Sathyabama Institute of Science and Technology, Chennai, The authors are grateful to the management of Sathyabama Institute of Science and Technology, Chennai, for supporting the original article. Professor K. R. Venkatesan, Principal, Sri Sankara Arts and Science College, Kanchipuram, Tamilnadu, India, has provided us with invaluable assistance and encouragement. This work was supported by the Deanship of Scientific Research, Vice Presidency for Graduate Studies and Scientific Research, King Faisal University, Saudi Arabia [Project No. GRANT1079].

Cells have developed a variety of mechanisms to counteract stress to give a specific and adaptive response. Yeast Hog1 is a homolog to mammalian p38, which is a mitogen-activated protein kinase. In this work, we analyze the Hog1 signaling during the induction of leptospiral LPS (100 ng/mL) and the hyperosmotic element NaCl (0.8 M). After the addition of stress elements, the stress-activated protein kinase was phosphorylated within 30 min of exposure and led to the expression of various genes responsible for cell survival. We found that leptospiral lipopolysaccharide mediated Hog1 phosphorylation leads to activation of autophagy-related genes phosphorylation; thereby cells encounter and digest the metabolic waste or organelles for their energy during starvation. And, the wild-type cells accumulate lipid droplets and trigger vacuole calcium release, to maintain cell survival. Loss of Hog1 leads to shrinkage in the cell wall, condensation of the cytoplasmic part, and high-level ROS production. This led to the Hog1 mutant cell death under LPS treatment or stress condition. The phosphorylation of stress-activated kinase during exposure to leptospiral LPS provides insight and knowledge about the organization of cellular metabolic products and cell survival during stress conditions and identifies the pathogenic mechanisms of leptospirosis.

Pseudomonas aeruginosa causes severe persistent infections in immunocompromised patients by showing tolerance conventional antibiotic therapy by virtue of specialized hierarchy of quorum sensing (QS) network. The purpose of the study was to evaluate the efficacy of two Mizoram medicinal plants i.e., Anogeissus acuminata and Mallotus roxburghianus Muell. in attenuating QS regulated P. aeruginosa virulence. The crude leaf extracts were tested for their ability to combat QS associated virulence phenotypes such as pyocyanin production, LasB elastase and Staphylolytic activity and production of biofilm determinants such as alginate and exopolysaccharide in P. aeruginosa PAO1. The gas chromatography mass spectrometry (GC-MS) analysis revealed the presence of phytocompounds, the synergistic activity of which is responsible for the anti QS activity. The in silico studies provide the binding efficacy of obtained phytochemical with QS receptor protein, LasR. The in vitro studies followed by in silico analysis demonstrated the efficacy of phytochemical of A. acuminata and M. roxburghianus Muell. in competitively inhibiting the binding of natural ligand with LasR and thereby altering production of virulence phenotypes. The efficacy in down regulating bacterial virulence shown by A. acuminata and M. roxburghianus Muell. provides promising alternatives to develop next generation anti-pathogenic agents.

Prebiotics are nondigestible food ingredients that stimulate the growth of bifidogenic and lactic acid bacteria in the gastrointestinal tract. Typically, the prebiotics consist of dietary fibers and oligosaccharides. Prebiotics exert a plethora of health-promoting effects, owing to which multimillion food and pharma industries have been established. Production of functional foods containing prebiotic ingredients is an area that has dominant featuring in the food industry in recent years and a very promising market, not only for economic reasons but also by scientific evidence of its benefits. Looking at the ever-increasing demand of prebiotics, recent trends in prebiotic production from new novel sources, from food industrial wastes, prebiotic supplementation in food, commercially available prebiotic agents, prebiotic production by various techniques, and future perspectives have been discussed. Aiming to satisfy this new market, some prebiotics especially inulin and fructooligosaccharide have been incorporated into a wide variety of foods and beverages that are part of a natural diet as dairy products, breads, cereals, dietary supplements, and others. Through this growth, consumers can appreciate tasty meals while promoting beneficial effects to their own health. The critical insight into this hot research area aims to stimulate further ponderance.

In the present study, we synthesis nanoparticles using biosynthesis methods because of the eco-friendly approach. Gold nanoparticles were synthesized using extracellular metabolites of marine bacteria (Rastrelliger kanagurta, Selachimorpha sp., and Panna microdon). After the synthesis gold nanoparticles checked their antibacterial and antimycobacterial activities. Here we have few techniques that have been used for characterizing the gold nanoparticles followed by ultraviolet (UV)-visible spectrophotometer analysis, Fourier transform-infrared spectroscopy (FTIR), X-ray diffraction (XRD), scanning electron microscope (SEM), and transmission electron microscopy (TEM). We observed the formation of gold nanoparticles using UV-Vis spectroscopy (UV-Vis). FT-IR spectroscopy results of the extracellular metabolites showed that different characteristic functional groups are responsible for the bioreduction of gold ions. In the recent years, we used zebrafish for an animal model to estimate nanoparticle toxicity and biocompatibility. We tested toxicity of the gold nanoparticle using the zebrafish larvae that are growing exponentially. Sample 1 showed a good antimicrobial activity, and sample 5 showed a good antimycobacterial activity. Based on the UV spectrophotometer, sample 1 is used for further studies. Color change and UV spectrum confirmed gold nanoparticles. Based on the TEM and SEM particles, size was measured and ranged between 80 and 45 nm, and most of the particles are spherical and are in rod shape. XRD result showed the gold nanoparticles with crystalline nature. Toxicity studies in the zebrafish larvae showed that 50 μg ml(−1) showed less toxicity. Based on the studies, gold nanoparticle has good antibacterial and antimycobacterial activities. The present was concluded that gold nanoparticles have potential biocompatibility and less toxicity. Gold nanoparticles will be used as a drug molecule in pharmaceutical company and biomedicine application.

Leptospirosis is considered as a neglected tropical disease which is caused by pathogenic Leptospira spp. The precise mechanisms of leptospirosis pathogenesis are unclear and hence, the progress in development of treatment modalities has been dismal. The present study aimed to identify novel virulent factors of leptospires to understand the disease pathogenesis and to develop treatment modalities. Leptospira interrogans contains two chromosomes and encodes for ~3703 genes, but the functions of several open reading frames have not yet been explored. Among them, novel virulent associated leptospiral proteins (LIC11334, LIC11542, LIC11436, LIC11120 and LIC12539) were identified using VirulentPredict and the antigenicity of these targets was explored by VaxiJen server. Domain architecture of the pathogen specific proteins revealed that LIC11334 had potential to evoke significant immune response against leptospiral infection and LIC11436 contains four folds of immunoglobulin-like domain and plays a vital role in pathogenesis. Therefore, B-cell epitopes were predicted and the epitope of high virulence (and VaxiJen score from LIC11334) was chemically synthesized as peptide (KNSMP01) and labeled with Biotin (Biotin-SGSGEVENPDPKVAQEC). Binding affinity of KNSMP01 with MHC molecules was predicted and the molecule was discovered to have potential to elicit both humoral and cell mediated immune responses and found to interact with host components via hydrophobic interaction, hydrogen bonding and salt bridges. Rabbit antisera was raised against KNSMP01 and found to elicit antigenicity using Western, ELISA and dot blot assays. In silico and in vitro experiments show KNSMP01 to be a promising immunogen and may be a better vaccine candidate for leptospirosis.

Based on our previous findings, two potent cyanobacterial strains namely, Anabaena sphaerica MBDU 105 and Nostoc calcicola MBDU 602 showed suitability for biodiesel production were chosen in this study to enhance biomass and lipid accumulation. The present study investigated the effect of nutrient supplementation with different carbons sources, chemical modulators and nutrient starvation on lipid accumulation. Nutrient supplementation with organic carbon sources yielded higher biomass (5.38–7.96 fold) and lipid productivity (2.81–2.19 fold) rather than lipid content. For chemical modulators, indole-3-carboxaldehyde (I3C) and kinetin (KT) increased lipid accumulation by 22 ± 1.9 and 34 ± 1 (% dwt), respectively. Therefore, central composite design was performed to assess the interactive effect of I3C and KT on lipid content, biomass and lipid productivity, fatty acid composition and their fuel properties. To the best of our knowledge, this is the first report demonstrating that I3C promote the biomass and lipid productivity of tested heterocystous cyanobacterial strains.

Pseudomonas aeruginosa is an important opportunistic pathogen which causes bacterial keratitis, cyctic fibrosis and other hospital acquired infections. Its ability to form biofilm provides resistance to conventional antibiotics and further corroborates the global health concerns. The antibiotic resistance by P. aeruginosa is due to highly complex cellular signaling system called quorum sensing (QS). As QS controls bacterial pathogenicity and plays a crucial role in biofilm formation, it is a promising alternative target to combat the bacterial virulence. The present study aims to determine the inhibitory activity of Plectranthus tenuiflorus extract on QS and biofilm development in P. aeruginosa PAO1. The crude plant extract inhibited the production of pyocyanin, elastase, protease and chitinase by 71.96 ± 1.82, 38.74 ± 1.29, 30.84 ± 1.20 and 44.75 ± 1.40 % respectively at sub-MIC concentration of 500 µg/ml. The production of biofilm aggravating phenotypes such as exopolysaccharides, alginate and rhamnolipid were also significantly reduced. The biofilm inhibition capability of P. tenuiflorus was further supported by light microscopic and confocal laser scanning microscopic analysis. The phytochemicals such as phytol and mosloflavone were identified from the crude extract using gas chromatography–mass spectrometry (GC-MS). The role of these phytochemicals in down regulation of QS in P. aeruginosa was further confirmed by in silico studies targeting transcriptional receptors, LasR and RhlR of the QS regulatory network. The in vitro and docking studies suggest the anti QS potential of P. tenuiflorus in combating the bacterial pathogenesis.

Pseudomonas aeruginosa is an opportunistic nosocomial pathogenic microorganism causing majority of acute hospital-acquired infections and poses a serious public health concern. The persistence of bacterial infection can be attributed to the highly synchronised cell-to-cell communication phenomenon, quorum sensing (QS) which regulates the expression of a number of virulence factors and biofilm formation which eventually imparts resistance to the conventional antimicrobial therapy. In this study, the anti-quorum sensing and anti-biofilm potential of ferulic acid encapsulated chitosan-tripolyphosphate nanoparticles (FANPs) was investigated against P. aeruginosa PAO1 and compared with native ferulic acid. Dynamic light scattering and transmission electron microscopic analysis confirmed the synthesis of FANPs with mean diameter of 215.55 nm. FANPs showed significant anti-quorum sensing activity by downregulating QS-regulated virulence factors. In addition, FANPs also significantly attenuate the swimming and swarming motility of P. aeruginosa PAO1. The anti-biofilm efficacy of FANPs as compared to native ferulic acid was established by light and confocal laser scanning microscopic analysis. The promising results of FANPs in attenuating QS highlighted the slow and sustained release of ferulic acid at the target sites with greater efficacy suggesting its application towards the development of anti-infective agents.

Serum samples from 840 animals were examined for Leptospira spp. antibodies by microscopic agglutination test (MAT) to assess the risk factors and the prevalence of leptospirosis among animal herds of Assam, Meghalaya, Mizoram the north eastern (NER) provinces. They were compared with Tamilnadu (TN) the southern province of India for the serovar and risk factor inconsistency. Serovar Ballum was reported to be prevalent (28.1 %) in Assam and Grippotyphosa (16.1 %) in Tamilnadu. The overall seropositivity observed was 36.8 %(206/560) from NER and 30.7 %(86/280) from TN. In this study, the higher seroprevalence was observed in pigs (42.6 %), cattle (39.8 %) and goats (26 %) in NER. Cattle (36.4 %) and goat (17.6 %) showed higher prevalence in TN. The presence of rodents in pig herds was found to be significant (P = 0.0088) in NER and it was for cattle in TN (P = 0.0063). We suggest that a program of rodent control should be included in the flock management practices aiming to reduce transmission of the leptospires.

The present investigation evaluates the potential of fifteen heterocystous cyanobacterial strains for biodiesel and hydrocarbon production. Fatty acid composition, biodiesel qualities along with biomass, lipid and hydrocarbon productivity were determined under autotrophic growth conditions. The biomass productivity of tested cyanobacterial strains ranged from 8.25 to 24.39 mg L−1 day−1 dry cell weight (DCW), whereas the lipid and hydrocarbon productivity ranged from 0.747 to 3.259 mg L−1 day−1 and 0.153 to 0.516 mg L−1 day−1, respectively. Palmitic acid (3.79–40.84%) and stearic acid (14.64–69.84%), which are favourable for biodiesel production, were predominantly present in tested cyanobacterial strains. Biodiesel fuel properties were estimated by empirical formulas based on FAME composition and met the prescribed criteria of international biodiesel standards like ASTM D6751 in the United States, EN 14214 in Europe and IS 15607 in India. Nostoc calcicola MBDU 602, with a lipid content of 18.921 ± 0.096 (% dwt), lipid productivity of 3.259 ± 0.211 mg L−1 day−1 and desirable fatty acid composition of C16-C18 (57.78%) was selected as the most suitable species for biodiesel production through PROMETHEE-GAIA analysis. The selected strain could possibly be exploited at commercial scale after further evaluation of up- and down-stream process at pilot experiment using photobioreactors.

The present study highlights the importance of cyanobacteria in plant growth promotion and screened the effect of biomass wet extract (BWE 1% and BWE 10%) of twenty cyanobacterial strains on the morphometric parameters of Pisum sativum L. seedlings after germination. Cyanobacterial BWE treatment significantly increased the radicle, plumule and total seedling length along with percentage of response than the control treatment with water. At BWE 1% treatment, Scytonema bohneri MBDU 104 showed 73.3% of the total seedling response, whereas Dolichospermum spiroides MBDU 903 showed increased total seedling length of 5.69 cm among other strains tested. All the tested strains varied among themselves at different parameters. To identify the most potent isolate, all the tested morphometric parameters were evaluated using a multi – criteria decision analysis (MCDA) of PROMETHEE-GAIA software. The isolate Scytonema bohneri MBDU 104 was selected as the potent plant growth promoting cyanobacteria and its BWE was purified using preparative – HPLC and analysed by LC-MS/MS for identifying possible plant growth elicitors. Phytohormones like indole-3 acetic acid (IAA), indole-3 butyric acid (IBA) and cinnamic acid along with free volatile fatty acids were identified and implicated for plant growth promotion by cucumber seed germination bioassay.

Milk-based products constitute a large portion of our diet, primarily in Asian countries specifically in Indian subcontinent. India is the largest milk producer in the world and home for the most popular fermented milk products. Fermented dairy products such as dahi (curd), mishti doi (sweetened curd), shrikhand, lassi, and chhach or mohi (buttermilk) are consumed frequently by the Indians. The current chapter is mainly focused on the technological innovations, nutritional and therapeutic properties of these products; new advances have been made to understand these aspects. Dietetic significance of Indian fermented milk products has been established due to their various nutritional and therapeutic properties.

Recently, biodiesel is gaining significant importance due to eco-friendly nature and development of large-scale production methodologies. Biodiesel is a mixture of mono-alkyl esters of fatty acids (FA). During transesterification, the long-chain FAs are combined with methanol to produce fatty acid methyl ester (FAME), the principle component of biodiesel. The biodiesel fuel properties are determined by structural components of FAs such as chain length, degree of unsaturation, and branching of the carbon chain. The fuel quality of biodiesel are evaluated by assessing the properties such as cetane number (CN), iodine value (IV), cold filter plugging point (CFPP), higher heating value (HHV), cloud point (CP), pour point (PP) etc., of FAME. The amount of lipid or fat produced may vary from organism to organism. A particular species may have high biomass with low lipid content and vice versa. So the selection of suitable species/genus by decision analysis software is much needed. Besides various multi-criteria decision analyses, Preference Ranking Organization Method for Enrichment of Evaluation (PROMETHEE) and Graphical Analysis for Interactive Aid (GAIA) analysis is considered as the most promising tool in selecting the prominent biodiesel producing strain. Here we describe the method of evaluating the fuel quality parameters for the produced FAME and selecting the prominent strain through PROMETHEE-GAIA algorithm.

An ever increasing energy demand and fast depletion of fossil fuels have led to increased consideration of bacterial lipids as a renewable biofuel source. Many methods are available for both physical and chemical extraction of bacterial lipids. The method of choice will depend on the nature of sample to be analyzed, combinations of solvent systems preferred, content and quality of the lipid to be analyzed, types of equipment available, and time of the extraction procedures employed. Here we describe the most reliable, routine method of extracting bacterial lipids and evaluating the growth kinetic parameters like biomass and lipid productivity and lipid content. We also describe the method of comparing bacterial fatty acid methyl ester peaks with standard peaks for analysis.

Pseudomonas aeruginosa is an opportunistic nosocomial pathogenic microorganism causing majority of acute hospital‐acquired infections and poses a serious public health concern. The persistence of bacterial infection can be attributed to the highly synchronised cell‐to‐cell communication phenomenon, quorum sensing (QS) which regulates the expression of a number of virulence factors and biofilm formation which eventually imparts resistance to the conventional antimicrobial therapy. In this study, the anti‐quorum sensing and anti‐biofilm potential of ferulic acid encapsulated chitosan‐tripolyphosphate nanoparticles (FANPs) was investigated against P. aeruginosa PAO1 and compared with native ferulic acid. Dynamic light scattering and transmission electron microscopic analysis confirmed the synthesis of FANPs with mean diameter of 215.55 nm. FANPs showed significant anti‐quorum sensing activity by downregulating QS‐regulated virulence factors. In addition, FANPs also significantly attenuate the swimming and swarming motility of P. aeruginosa PAO1. The anti‐biofilm efficacy of FANPs as compared to native ferulic acid was established by light and confocal laser scanning microscopic analysis. The promising results of FANPs in attenuating QS highlighted the slow and sustained release of ferulic acid at the target sites with greater efficacy suggesting its application towards the development of anti‐infective agents.

Lipopolysaccharide (LPS) is the major surface antigen of Leptospira. In this study, the genes involved in the LPS biosynthesis were analyzed and compared by bioinformatics tools. Also, the chemical composition analysis of leptospiral lipopolysaccharides (LPS) extracted from 5 pathogenic serovars like Autumnalis, Australis, Ballum, Grippotyphosa, Pomona, and the nonpathogenic serovar Andamana was performed. Methods used were Limulus amebocyte lysate assay (LAL), gas chromatography-mass spectrometry (GC-MS), fourier transform infrared spectroscopy (FT-IR), and nuclear magnetic resonance spectroscopy (NMR). LAL assay showed a significantly higher level of endotoxicity among pathogenic serovars (~0.490 EU/mL) than that of nonpathogenic Andamana (~0.102 EU/mL). FAMES analysis showed the presence of palmitic acid (C16:0), hydroxy lauric acid (3-OH-C12:0), and oleic acid (C18:0). Palmitoleic acid (C16: 1), and 3- hydroxy palmitate (3-OH-C16:0) was detected only in pathogenic serovars. In contrast myristoleic acid (C14:1) and stearic acid (C18:0) were present in Andamana. FTIR analysis revealed C–O–C stretch of esters, 3°ROH functional groups and carbohydrate vibration range were similar among pathogenic serovars. The NMR analysis reveals similarity for 6 deoxy sugars and methyl groups of Autumnalis, Australis, and Ballum. Further, the presence of palmitoleic acid and 3-hydroxy palmitate may be the significant pathogen-associated predisposing factor. This mediates high osmolarity glycerol (HOG) mediated stress response in leptospiral LPS mediated pathogenesis.

In this study, 27 strains of Lactic acid bacteria (LAB) were isolated and identified from different milk sources. All the isolates were biochemically characterized and screened for their ability to produce exopolysaccharides (EPS), among which two isolates namely Lactobacillus plantarum NTMI05 (197mg/L) and Lactobacillus plantarum NTMI20 (187mg/L) showed higher EPS production. Both the isolates were molecular characterized and tested for their probiotic properties. The chemical composition of EPS from L. plantarum NTMI05 and NTMI20 revealed the presence of 95.45% and 92.35% carbohydrates, 14±0.1and 11±0.15mg/L lactic acid, 10.5±0.2 and 9±0.1mg/mL of reducing sugar, respectively. HPLC analysis showed galactose at the retention time of 2.29.The maximum EPS yield was optimized for the media components like glucose (20g/L), yeast extract (25g/L) and ammonium sulphate (2g/L) using Central Composite Design and Response Surface Methodology (RSM). Under optimum conditions the predicted maximum EPS production was 0.891g/L, 0.797g/L, while the actual experimental value was 0.956g/L and 0.827g/L for L. plantarum NTMI05 and NTMI20, respectively. The antioxidant capacity was also evaluated by DPPH and reducing power assay proving the potentiality of these organisms in food and dairy industries.

An ever increasing energy demand and fast depletion of fossil fuels have led to increased consideration of bacterial lipids as a renewable biofuel source. Many methods are available for both physical and chemical extraction of bacterial lipids. The method of choice will depend on the nature of sample to be analyzed, combinations of solvent systems preferred, content and quality of the lipid to be analyzed, types of equipment available, and time of the extraction procedures employed. Here we describe the most reliable, routine method of extracting bacterial lipids and evaluating the growth kinetic parameters like biomass and lipid productivity and lipid content. We also describe the method of comparing bacterial fatty acid methyl ester peaks with standard peaks for analysis.

Recently, biodiesel is gaining significant importance due to eco-friendly nature and development of large-scale production methodologies. Biodiesel is a mixture of mono-alkyl esters of fatty acids (FA). During transesterification, the long-chain FAs are combined with methanol to produce fatty acid methyl ester (FAME), the principle component of biodiesel. The biodiesel fuel properties are determined by structural components of FAs such as chain length, degree of unsaturation, and branching of the carbon chain. The fuel quality of biodiesel are evaluated by assessing the properties such as cetane number (CN), iodine value (IV), cold filter plugging point (CFPP), higher heating value (HHV), cloud point (CP), pour point (PP) etc., of FAME. The amount of lipid or fat produced may vary from organism to organism. A particular species may have high biomass with low lipid content and vice versa. So the selection of suitable species/genus by decision analysis software is much needed. Besides various multi-criteria decision analyses, Preference Ranking Organization Method for Enrichment of Evaluation (PROMETHEE) and Graphical Analysis for Interactive Aid (GAIA) analysis is considered as the most promising tool in selecting the prominent biodiesel producing strain. Here we describe the method of evaluating the fuel quality parameters for the produced FAME and selecting the prominent strain through PROMETHEE-GAIA algorithm.

The efficiency of cyanobacterial strains as biodiesel feedstock varies with the dwelling habitat. Fourteen indigenous heterocystous cyanobacterial strains from rice field ecosystem were screened based on growth kinetic and fuel parameters. The highest biomass productivity was obtained in Nostoc punctiforme MBDU 621 (19.22 mg/L/day) followed by Calothrix sp. MBDU 701 (13.43 mg/L/day). While lipid productivity and lipid content was highest in Nostoc spongiaeforme MBDU 704 (4.45 mg/L/day and 22.5% dwt) followed by Calothrix sp. MBDU 701 (1.54 mg/L/day and 10.75% dwt). Among the tested strains, Nostoc spongiaeforme MBDU 704 and Nostoc punctiforme MBDU 621 were selected as promising strains for good quality biodiesel production by Preference Ranking Organization Method for Enrichment Evaluation (PROMETHEE) and Graphical Analysis for Interactive Assistance (GAIA) analysis.

The present study aims to develop an efficient and simple protocol for in vitro plant regeneration using cyanobacterial liquid medium. The ability of the unicellular cyanobacterium Aphanothece sp. MBDU 515 to produce the phytohormone indole-3-acetic acid (IAA) in the medium was demonstrated and chemically analyzed by Salkowski assay, High performance liquid chromatography (HPLC) and Gas chromatography–Mass spectrometry (GC/MS). The effect of cyanobacterial extracellular product (CEP) for in vitro propagation was evaluated on two economically important plants Arachis hypogaea and Moringa oleifera . The effect of commercial phytohormones 6-Benzylaminopurine (BAP) and Indole-3-butyric acid (IBA) in shoot and root induction, respectively was compared with CEP in both the plants. In the present study, it was observed that 1 mL of CEP per 10 mL of MS basal medium showed an increase in % of shoot and root responses, shoot and root lengths and average number of roots per shoot compared to the control (MS basal medium). These effects of CEP are comparable to the commercial phytohormones — BAP and IBA, tested. The tested CEP markedly reduced the accumulation of phenolics in A. hypogaea explants. Our study suggests that CEP may be used for micropropagtion at industrial scale instead of commercially available phytohormones.

Marine Lyngbya has been proven as a potent anticancer agent by disrupting microfilament network. Lyngbya and its associated cyanobacterial compounds have been stressed for futuristic advancements in cancer research and have foreseen explicit advancements in the recent era. Moreover, compounds like lyngbyabellins, lyngbyastatins and other derived toxins are significantly studied. Therefore it is of interest to study the efficacies of Lyngbya fatty acid derivatives. Cytotoxicity and DNA laddering studies proves the efficiency and safety of marine Lyngbya. Caspase - 3 along with MMP2 and MMP9 affirms the anti-inflammatory properties. Molecular docking shows that Octadecanoic acid has strong binding affinity to MMP-2. The role of octadecanoic acid as a proapoptotic factor in emancipation of inflammation apart from inducing apoptosis is of interest to study in future.

Trichodesmium is an enigmatic bloom forming, non-heterocystous cyanobacterium reported most frequently in the coastal waters of India. However, the toxigenic potential of this globally significant N2 fixing cyanobacterium has not been characterized. In this study, we report for the first time the presence of potent multi-class neurotoxins such as Anatoxin-a, Saxitoxins, Gonyautoxin and hepatotoxins like MC-LR, MC-YA from a bloom material of Trichodesmium sp. MBDU 524 collected at the Gulf of Mannar region. Toxins were determined using liquid chromatography-electrospray ionization mass spectrometry (LC-ESI-MS) analysis of HPLC purified aqueous and solvent fractions. Molecular phylogenetic analysis through 16S rRNA gene sequencing showed the close relationship with Trichodesmium erythraeum clade. The toxigenic potential was validated through brine shrimp toxicity assay and showed 100% mortality after 48 h of incubation. The results suggest the potential toxigenic and environmental impacts of Trichodesmium bloom sample from the Gulf of Mannar region.

Crude oil is the most important raw material used in chemical industry and for energy supply. Microbial lipids are ideal for various industrial applications as an alternative to conventional fuel. However, the main factor controlling the total production costs is the choice of the growth substrates. For this reason, economically feasible substrate such as agro-industrial residues has been explored. In addition, the most suitable substrates for biodiesel production were selected by PROMETHEE-GAIA analysis on the basis of the fatty acid profile of the produced oils. Six strains were selected as the best lipid producer among twenty-three fungal strains screened by colorimetric methods. The strains identified belong to the genera Fusarium and Mucor. Mucor circinelloides was chosen for comparative evaluation of the accumulation performance with different carbon sources. The use of soap stock of refined soybean oil, waste cooking oils and soap stock of refined olive-pomace successfully resulted in improved lipid yield (4.07, 2.69 and 2.44 g/L) (ρ = 0.001; ρ > 0.05) and the lipid content at 46%, 51% and 44% (ρ = 0.049; ρ

Microvirin, a mannose binding anti-HIV (Human Immunodeficiency virus) lectin has been proved as a potent agent in combating HIV. Ligand binding residues of Microvirin was taken in to account for analysis of interfacial residues and identify surface/Buried residues based on Accessible surface area and free energy based calculations. After categorization, Comparative B factors were assessed for prediction of Rigid/Non-Rigid residues among the Ligand binding residues. Furthermore docking microvirin with glycoproteins gp120 and gp41 revealed the conserved interfacial residues in complexes and affirms the computational dissection of microvirin’s anti-HIV activity.

Objective To evaluate the in vitro antibacterial activity of various solvent extracts of South Indian traditional medicinal plants Ocimum sanctum, Ocimum gratissimum, Aegle marmelos , and Adhatoda vasica leaves against clinical pathogens of human origin. Methods The antimicrobial activity of different solvents crude extract of four medicinal plants used in traditional Indian medicine was tested by disc diffusion method against five bacterial pathogens: Escherichia coli, Staphylococcus aureus , Salmonella typhi, Salmonella paratyphi and klebsiella pneumoniae. . The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) was determined for evaluating the potential plant extract. Results The antibacterial results showed methanol extracts (0.4 g/ml) of Ocimum gratissimum and Ocimum sanctum showed maximum zone of inhibition (30 mm and 25.5 mm, respectively) against Salmonella typhi . MIC was tested at various concentrations from 0.625 mg/ml to 0.039 mg/ml for all the plant extracts. At the lowest concentration (0.039mg/ml) tested, methanol extracts of Ocimum gratissimum showed higher MIC against Salmonella typhi and Salmonella paratyphi where as the methanolic extracts of Ocimum gratissimum showed potent activity against Staphylococcus aureus at 0.078 mg/ml. Methanol extract (0.4 g/ml) of Aegle marmelos showed significant inhibitory activity of 22.5mm and MIC value of 0.156.mg/ml against E. coli strain. The Klebsiella spp was the most resistant strain of all and various concentrations Adhatoda vasica extract showed less activity against the tested pathogens. Conclusions The present screening result demonstrated that the Indian traditional medicinal plants Ocimum sanctum, Ocimum gratissimum, Aegle marmelos methanol leaf extract has potent antibacterial activity and the studied plants may be new source for novel antibacterial compound discovery for treating drugs resistant human pathogens.

PCR amplification techniques viz., repetitive DNA element PCR (REP-PCR), short tandemly repeated repetitive PCR (STRR-PCR) and arbitrarily primed PCR (RAPD-PCR) were used for the taxonomic discrimination among the strains of the unicellular cyanobacterium Synechococcus elongatus collected across the coastal regions of the Indian subcontinent. These strains showed similar phenotypic and genotypic characteristics. Data obtained from genomic fingerprinting were used to perform cluster analysis and demonstrated ability to differentiate strains at intra-specific level. Polymorphisms of different PCR amplification products can serve as strain-specific molecular fingerprints. In comparison with the STRR and RAPD, the REP primer set generates fingerprints of lower complexity, but still the phenogram clearly differentiated the strains. In conclusion, described PCR fingerprinting methods can be considered as promising tools for the differentiation at the strain level of cyanobacteria from the same species.

The aim of this study was to analyze marine cyanobacterial culture collections strains of the Indian subcontinent at the level below species. This is important to improve the abilities of service culture collections to provide their user community with correctly identified and clean organisms. A total of 50 marine cyanobacterial strains were genotyped with M13 polymerase chain reaction (PCR) fingerprinting to provide diagnostic fingerprints for each culture. Depending on the strains, 9 to 26 bands were observed for the primer tested. Within the species, strains representing different isolates were genetically clearly different. Data obtained from genomic fingerprinting were used to construct binary distance matrix, and the neighbor-joining tree constructed demonstrated the ability of this method to differentiate strains at the intraspecific level. An important and useful result obtained in this study is the application of the M13 PCR fingerprinting method on almost all forms of cyanobacteria for strain and species discrimination.

Cyanobacterial biodiversity from different freshwater ponds of Thanjavur, Tamilnadu(India). Studies on the cyanobacterial biodiversity of 5 different freshwater ponds in and aroundThanjavur, Tamilnadu during summer month (June, 2004) has been made and compared their variationsamong five different ponds. In addition, certain physico-chemical parameters of pond waters such asdissolved oxygen, net productivity, pH, carbonate, bicarbonate, nitrate, nitrite, total phosphorus,inorganic phosphorus etc. were also analyzed and statistically compared with the cyanobacterialdiversity. Totally 39 species of 20 genera of cyanobacteria were recorded in all 5 different ponds.Only 6 species of cyanobacteria were identified in Pond 1 (Dabeerkulam), where a massive bloom ofMicrocystis aeruginosa was recorded, which had a significant effect in reducing the othercyanobacterial population. As many as five species namely Aphanothece microscopica, Synechocystisaquatilis, Merismopedia glauca, Oscillatoria limnetica and O. subbrevis were common in all theponds surveyed except in Pond 1.Key words. Biodiversity, ecosystem, cyanobacteria, Oscillatoria, Microcystis.RESUMEN. Biodiversidad de cianobacterias en diferentes charcas de agua dulce de Thanjavur,Tamilnadu (India). Se ha inventariado, y comparado entre sí, la biodiversidad de cianobacterias de 5charcas de agua dulce de Thanjavur, Tamilnadu (India); el estudio se llevó a cabo en junio de 2004.En paralelo, también se determinaron los valores de ciertos parámetros físico-químicos que podríanexplicar las variaciones en los valores de biodiversidad: oxígeno disuelto, productividad neta, pH,carbonato, bicarbonato, nitrato, nitrito, fósforo total, fósforo inorgánico, etc. Un total de 39 especiesde 20 géneros de cianobacterias se identificaron entre las 5 charcas. En la charca 1 (Dabeerkulam) sedetectaron 6 especies, pero cuando tuvo lugar una flor de agua de Microcystis aeruginosa las restantesespecies apenas se pudieron detectar. Cinco especies (Aphanothece microscopica, Synechocystisaquatilis, Merismopedia glauca, Oscillatoria limnetica y O. subbrevis fueron comunes en todas lascharcas con excepción de la número 1.Palabras clave. Biodiversidad, cianobacterias, ecosistema, Oscillatoria, Microcystis.

Plants in nature always grow with soil microorganisms, and some become intimately associated with plants to form mutualistic symbiosis. Examples of such symbiotic microorganisms include mycorrhizal fungi, cyanobacteria, and N2-fixing prokaryotes, especially rhizobia. Looser symbiotic associations involve bacteria and soil microfauna within the rhizosphere. Their metabolic activities increase nutrient availability. All of these symbioses may affect rates of growth and eventually reproduction of plants compared with growth in the absence of such associations. A symbiotic association is therefore a potential selection pressure that can influence the evolutionary success of vascular plants and hence the composition of plant communities. Application of associative bacteria for sustainable agriculture holds immense potential. These bacteria are known to enhance growth and yield of plants by fixing atmospheric nitrogen, solubilization of phosphate, production of phytohormones and siderophores, possession of antagonistic activity, as well as reducing the level of stress ethylene in host plants. This review provides examples of associations and interactions between microorganisms and plants. The cyanobacterial association with various plants such as bryophyte, pteridophyte, gymnosperm, and angiosperm was illustrated. It also describes the actinorhizae, Frankia and Rhizobium, interaction with plants and their applications.

This study reports on the biodiesel quality parameters of eleven heterocystous cyanobacterial strains based on fatty acid methyl esters (FAME) profiles. The biomass productivity of the tested cyanobacterial strains ranged from 9.33 to 20.67 mg L(-1) d(-1) while the lipid productivity varied between 0.65 and 2.358 mg L(-1) d(-1). The highest biomass and lipid productivity was observed for Calothrix sp. MBDU 013 but its lipid content is only 11.221 in terms of percent dry weight, next to the Anabaena sphaerica MBDU 105, whose lipid content is high. To identify the most competent isolate, a multi-criteria decision analyses (MCDA) was performed by including the key chemical and physical parameters of biodiesel calculated from FAME profiles. The isolate A.sphaerica MBDU 105 is the most promising biodiesel feed stock based on decision vector through Preference Ranking Organisation Method for Enrichment Evaluation (PROMETHEE) and Graphical Analysis for Interactive Assistance (GAIA) analysis.

Secreted aspartyl proteinases (SAP) are the key virulence factors that play a central role in the pathogenesis of Candida albicans and always are the best target for designing potent antifungal agents. Cyanobacteria have already been recognized to provide chemical and pharmacological novelty and diversity over conventional sources of drugs for combating major diseases ranging from AIDS to cancer. In this study, the two ABC transporter systems - permease proteins from Microcoleus chthonoplastes PCC 7420 were modeled and the protein-protein interaction assessment of the modeled proteins with selective secreted aspartyl proteinases of Candida albicans was attempted. The modeled proteins were assigned PMDB IDs PM0077423 and PM0077424. The secreted aspartyl protease 5 of Candida albicans showed effective interaction with ABC transporter permease protein 2 of Microcoleus chthonoplastes PCC 7420. Hydrophobic interactions were found between Tyr, Phe and Pro in chain A and Pro and Tyr in chain B. Our results of the docked complexes clearly demonstrated the potentiality of permease proteins in arresting the virulence nature of SAP of Candida albicans effectively. This study is first of its kind in addressing the therapeutic intervention of virulence nature of Candida albicans by the cyanobacterial system.

The morphological and genetic diversity of cyanobacteria associated with cycads was examined using PCR amplification techniques and 16S rRNA gene sequence analysis. Eighteen symbiotic cyanobacteria were isolated from different cycad species. One of the symbiotic isolates was a species of Calothrix, a genus not previously reported to form symbioses with Cycadaceae family, and the remainder were Nostoc spp. Axenic cyanobacterial strains were compared by DNA amplification using PCR with either short arbitrary primers or primers specific for the repetitive sequences. Based on fingerprint patterns and phenograms, it was revealed that cyanobacterial symbionts exhibit important genetic diversity among host plants, both within and between cycad populations. A phylogenetic analysis based on 16S rRNA gene sequence analysis revealed that most of the symbiotic cyanobacterial isolates fell into well-separated clades. (© 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

Hypersaline Phormidium strains were grown in media amended with naphthalene and anthracene. Phormidium tenue was identified as tolerating and effectively degrading polycyclic aromatic hydrocarbons that may be toxic in the environment. GC/MS analysis explained the degradation of these compounds by P. tenue. A dioxygenase enzyme system was evident by the formation of anthracene dione as the first degradation compound. This strain could be used for bioremediation of polycyclic aromatic hydorcarbon pollution on seashores.

Self-splicing group I introns in tRNA anticodon loops have been found in diverse groups of bacteria. In this work, we identified tRNAfMet group I introns in six strains of marine Synechococcus elongatus. Introns with sizes around 280 bp were consistently obtained in all the strains tested. In a phylogenetic analysis using the nucleotide sequence determined in this study with other cyanobacterial tRNAfMet and tRNALeu intron sequences, the Synechococcus sequence was grouped together with the sequences from other unicellular cyanobacterial strains. Interestingly, the phylogenetic tree inferred from the intronic sequences clearly separates the different tRNA introns, suggesting that each family has its own evolutionary history.