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PURPOSE OF THIS REVIEW: Manipulating or re-engineering the damaged human spinal cord to achieve neuro-recovery is one of the foremost challenges of modern science. Addressing the restricted permission of neural cells and topographically organised neural tissue for self-renewal and spontaneous regeneration, respectively, is not straightforward, as exemplified by rare instances of translational success. This review assembles an understanding of advances in nanomedicine for spinal cord injury (SCI) and related clinical indications of relevance to attempts to design, engineer, and target nanotechnologies to multiple molecular networks. RECENT FINDINGS: Recent research provides a new understanding of the health benefits and regulatory landscape of nanomedicines based on a background of advances in mRNA-based nanocarrier vaccines and quantum dot-based optical imaging. In relation to spinal cord pathology, the extant literature details promising advances in nanoneuropharmacology and regenerative medicine that inform the present understanding of the nanoparticle (NP) biocompatibility-neurotoxicity relationship. In this review, the conceptual bases of nanotechnology and nanomaterial chemistry covering organic and inorganic particles of sizes generally less than 100 nm in diameter will be addressed. Regarding the centrally active nanotechnologies selected for this review, attention is paid to NP physico-chemistry, functionalisation, delivery, biocompatibility, biodistribution, toxicology, and key molecular targets and biological effects intrinsic to and beyond the spinal cord parenchyma. SUMMARY: The advance of nanotechnologies for the treatment of refractory spinal cord pathologies requires an in-depth understanding of neurobiological and topographical principles and a consideration of additional complexities involving the research's translational and regulatory landscapes.

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Alginate/lignin is a synthetic polymer rich in biological activity and is of great interest. Alginate is extracted from seaweed and lignin is extracted from corn stalks and leaves. In this paper, antioxidant activities of alginate/lignin were evaluated, such as total antioxidant activity, reducing power activity, DPPH free radical scavenging activity, and α-glucosidase inhibition activity. Anticancer activity was evaluated in three cell lines (Hep G2, MCF-7, and NCI H460) and fibroblast. Physico-chemistry characteristics of alginate/lignin were determined through FTIR, DSC, SEM_EDS, SEM_EDS mapping, XRD, XRF, and 1H-NMR. The acute toxicity of alginate/lignin was studied on Swiss albino mice. The results demonstrated that alginate/lignin possessed antioxidant activity, such as the total antioxidant activity, and reducing power activity, especially the α-glucosidase inhibition activity, and had no free radical scavenging activity. Alginate/lignin was not typical in cancer cell lines. Alginate/lignin existed in a thermally stable and regular spherical shape in the investigated thermal region. Six metals, three non-metals, and nineteen oxides were detected in alginate/lignin. Some specific functional groups of alginate and lignin did not exist in alginate/lignin crystal. Elements, such as C, O, Na, and S were popular in the alginate/lignin structure. LD0 and LD100 of alginate/lignin in mice were 3.91 g/kg and 9.77 g/kg, respectively. Alginate/lignin has potential for applications in pharmaceutical materials, functional foods, and supporting diabetes treatment.

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Atmospheric nitrogen deposition has a crucial impact on the structure and function of soil microorganisms of wetland ecosystems. Therefore, carrying out a study on the effects of soil carbon metabolism capacity has a great significance for the protection and utilization of wetland ecosystems. In this study, the effects of simulated nitrogen deposition on the carbon metabolic capacity of soil microorganisms in Calamagrostis angustifolia wetland for five consecutive years was investigated using Biolog-Eco technology. The results showed:① soil water content (SMC), pH, nitrate nitrogen (NO3-), ammonium nitrogen (NH4+), dissolved organic carbon (DOC), and total nitrogen (TN) contents were significantly different (P<0.05) under different nitrogen deposition conditions. ② The average well color development (AWCD) values of soil microorganisms within different N depositions were in the order of CK (control)>HN (high nitrogen treatment)>LN (low nitrogen treatment). LN significantly reduced the Shannon diversity index of soil microorganisms, and HN significantly reduced the Pielou index of soil microorganisms (P<0.05). ③ LN significantly inhibited the intensity of the utilization of carbohydrates, alcohols, amines, and acids by soil microorganisms (P<0.05); HN significantly promoted the utilization of esters by microorganisms, but HN caused soil microorganisms to inhibit the carbon sources of carbohydrates, amines, and acids (P<0.05). ④ Redundancy analysis showed that NH4+, DOC, and pH were the main environmental factors affecting the functional diversity of soil microbial communities in Calamagrostis angustifolia wetland in the Sanjiang Plain. Long-term nitrogen deposition will lead to the reduction in soil microbial functional diversity; the microbial activity related to the utilization of carbon source substrates is also significantly reduced, and the ability of microorganisms to utilize a single carbon source substrate also changes.

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BACKGROUND: This study aimed to investigate the effects of the supplementation of sesame flour in fermented chicken sausages ('S1' containing 800 g kg-1 chicken fillet, 180 g kg-1 veal fat and 20 g kg-1 sesame flour and 'S2' containing 800 g kg-1 chicken fillet, 160 g kg-1 veal fat and 40 g kg-1 sesame flour) compared with control sausages (containing 800 g kg-1 chicken fillet and 200 g kg-1 veal fat) on the physico-chemical characteristics, texture, and structure during the fermentation stage. RESULTS: The physicochemical parameters of samples belonging to the control, S1, and S2 batches were significantly affected by the addition of sesame flour and the fermentation stage. For instance: (i) the lowest protein content was observed for control samples on day 1 (61.4 ± 6.52 g kg-1 ) whereas the highest level was noted for S2 samples on day 15 (327.5 ± 22.2 g kg-1 ), and (ii) an inverse trend was observed for the fat content because the lowest content was observed for samples in the S2 batch on day 1 (129.0 ± 5.30 g kg-1 ) whereas the highest fat content was noted for samples belonging to control batch on day 15 (332.0 ± 1.29 g kg-1 ). The application of statistical methods to mid-infrared spectroscopy allowed clear discrimination between control, S1, and S2 batches. The addition of sesame flour in the recipes induced some modification in the secondary structure because ß-turn levels ranged from 39.30 to 34.50, 36.76 to 34.70, and 38.93 to 34.70 for control, S1, and S2 batches, respectively, throughout the fermentation stage. Sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) showed a similar protein profile pattern in the three batches on days 1 and 5, but on day 10 control and S2 batches showed the most intense degradation of myofibrillar proteins. CONCLUSION: The results demonstrated that mid-infrared spectroscopy coupled with chemometric tools could be used as a rapid screening tool to assess and monitor the quality of dry chicken sausages enriched with sesame flour throughout the fermentation stage. © 2022 Society of Chemical Industry.

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BACKGROUND: This is a study about the skin ageing exposome, focusing on the effect of cigarette smoke. Human living skin explants (HSE) were exposed to cigarette smoke (CS) of two cigarettes for 2 hours using a custom-made exposure chamber, the Pollubox® . Effects on the surface physico-chemistry and molecular properties of the skin were analyzed and reported for the first time. BASIC PROCEDURES: To this end, transcriptomic study followed by immunohistochemistry, MDA (Malondialdehyde Dosage), and surface physio-chemistry data: surface free energy determination, TEWL (Trans Epidermal Water Loss), skin pH and FT-IR (Fourier Transform-Infrared) spectroscopy of the explant were collected from untreated and treated HSE. MAIN FINDINGS: Results showed a decrease of the total surface free energy of the treated HSE. This decrease reflected higher interactions with polar compounds from the environment and consequently a decrease of the surface hydrophobicity. Additionally, an increase of TEWL and skin pH was observed after treatment. The transcriptomic analysis showed downregulation of mitochondrial genes (PON2-NDUFA4L2-ATP1A1-ALDH2-PRODH) combined with an increase of MDA in CS-treated HSE. CONCLUSIONS: CS-induced oxidation of lipids at HSE surface alters the skin barrier: interactions with polar products are enhanced and the lipid chain packing at the surface is modified. Consequently, skin permeability could increase which correlated with repression of CA9 and AQP1 genes. Beside activation of AHR-NRF2 pathway in CS-exposed HSE, our results suggested that mitochondrial functions were strongly impacted and oxidized lipids failed to be eliminated promoting skin barrier alteration. A mitophagy activity was suggested through the confirmation of PINK1 accumulation in the epidermis by immunostaining.

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In temperate and boreal forests, competition for soil resources between free-living saprotrophs and ectomycorrhizal (EcM) fungi has been suggested to restrict saprotrophic fungal dominance to the most superficial organic soil horizons in forests dominated by EcM trees. By contrast, lower niche overlap with arbuscular mycorrhizal (AM) fungi could allow fungal saprotrophs to maintain this dominance into deeper soil horizons in AM-dominated forests. Here we used a natural gradient of adjacent forest patches that were dominated by either AM or EcM trees, or a mixture of both to determine how fungal communities characterized with high-throughput amplicon sequencing change across organic and mineral soil horizons. We found a general shift from saprotrophic to mycorrhizal fungal dominance with increasing soil depth in all forest mycorrhizal types, especially in organic horizons. Vertical changes in soil chemistry, including pH, organic matter, exchangeable cations, and extractable phosphorus, coincided with shifts in fungal community composition. Although fungal communities and soil chemistry differed among adjacent forest mycorrhizal types, variations were stronger within a given soil profile, pointing to the importance of considering horizons when characterizing soil fungal communities. Our results also suggest that in temperate forests, vertical shifts from saprotrophic to mycorrhizal fungi within organic and mineral horizons occur similarly in both ectomycorrhizal and arbuscular mycorrhizal forests.

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A physico-chemical approach was used for characterizing and generating fingerprints of single (L. bulgaricus and S. thermophilus) and multiple (Vivomixx) probiotic species. Such a methodology included thermal, colloidal, and surface analyses of powder (solid-in-gaseous phase) and dispersed (solid-in-aqueous phase) samples. Decomposition and transition phases analyzed by thermogravimetry and differential scanning calorimetry provide specific qualitative and quantitative data that serve as a probiotic fingerprint, and therefore a product quality control for each sample. Investigation of colloidal and surface properties of dispersed samples by light scattering and contact angle measurements informs on the probiotic size average, electrokinetic charge, and surface hydrophobicity. Besides their relevance in identity control, the physico-chemical data are also useful in probiotic performance prediction, since they govern the most crucial microbial functionalities such as thermostability, aggregation, and adhesion.

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Search dogs are used throughout the world in the search for illicit compounds or human individuals and similar tasks. Such search work is complex and not well understood in all its details which makes training of the dogs difficult. One important component for a successful education and deployment of search dogs is a good understanding of the behavior of scents under typical environmental conditions. This work summarizes up-to-date knowledge on the physico-chemistry of scents and discusses the consequences for the every-day work of dog handlers and trainers.

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Physico-chemical properties such as surface free energy, polarity or hydrophobicity of solid surfaces have been largely studied in literature because they are involved in many physical phenomena: adhesion, friction, wetting … Nowadays, the study of biointerfaces is of great interest for the medical, the pharmaceutical or the cosmetic field but also for material design researches, especially for the development of biomimetic surfaces. The present paper focuses on a particular biointerface, namely skin, which is the most extended organ of the human body. The different ways for the study of skin physico-chemistry are first reviewed, followed by their practical uses, from pharmaceutical to cosmetic science. Those properties depict the ways skin interacts with topical products, its lipid composition but also its hydration state. In addition, this article aims to present recent approaches using original model materials in order to mimic human skin; indeed, in vivo experiments are often limited by the inter and intra individual variability, the safety regulation and above all the time and the cost of such studies. Finally, further data clearly highlight the importance of skin surface properties for dermatological and pharmaceutical researches.

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The article contains datasets built on a baseline study on the selected physicochemical parameters and Water Quality Index of Ubogo and Egini Rivers, Delta State, for a period of six months, spanning the time frame between February - July, 2010. Within this space, six stations were shared equally among the two rivers using the three communities they flow through as guide, and water samples were collected on monthly basis from these stations. The objectives include determination of the spatial variations and background concentrations of the selected physicochemical parameters. Sixteen physicochemical parameters were analyzed in the water. Current velocity, air and water temperature were determined in-situ; the rest physicochemical parameters were determined via adopting standard methods. Apart from turbidity, the values of the rest physical parameters - air and water temperature, TDS showed significant difference (p < 0.05) across the stations.

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Urban stormwater affects the general quality of water bodies because of their hydraulic and pollution impacts. Stormwater discharges modify stream water flow and are reported as major source of heavy metals (HMs) in urban streams. Stormwater Constructed Wetlands (SCWs) have been built worldwide to manage stormwater before it is released into hydrosystems. In SCWs, stormwater is stored, evaporated and sometimes infiltrated. Subsequently, the HMs in stormwater can be settled, filtered and bioassimilated by microorganisms. Hence, the efficiency of SCWs in managing stormwater depends on climatic conditions, which change with season. The aim of this study was to investigate the impacts of seasonality on the performance of a 6-year-old constructed wetland made with a pond followed by a vertical flow filter. Hydraulic performance of, physico-chemical behaviour of, and HM mitigation via the SCW were evaluated using over 3 years of monitoring (2015-2017) data. Only 35% of the rain events that occurred in the studied catchment caused a discharge into the pond and 17% into the filter. The SCW was mostly supplied with stormwater in spring and summer and provided peak flow attenuation from 97 to 100% in all seasons. Variations in physico-chemical parameters (temperature, dissolved oxygen, pH, and redox potential) were caused by seasonal and dry/wet weather changes. They were greater in the pond than in the filter, which buffers these variations. The high physico-chemical variations in the pond probably had a deleterious effect on HM storage in the pond sediments. Finally, hydrologic and physico-chemical conditions (antecedent dry period length, pH, redox potential) affected the HM concentrations along the SCW. However, HM removal efficiencies were >97% in all seasons.

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The concentrations of four heavy metals (Zn, Fe, Cu, and Pb) in water, sediment, and tissues (gill, muscle, brain, and intestine) of Oreochromis niloticus from a segment of the Lagos Lagoon complex were monitored for 10 months (July 2012-April 2013) spanning wet and dry seasons. Three sampling stations were selected: Ologe Lagoon, the nearest to the point where effluent is discharged from Agbara Industrial Estate, the Owo River is upstream before the point of discharge of industrial effluent, and Etegbin is downstream. In most cases, the highest concentrations of heavy metal in fish tissues were recorded in samples obtained from Ologe Lagoon. The ranges of concentrations of heavy metals in the tissues of the fish were 4.06 ± 2.45-49.94 ± 13.11, 81.27 ± 28.52-2044.64 ± 554.77, 10.90 ± 7.69-41.10 ± 11.24, and 0.12 ± 0.07-1.81 ± 3.12 mg/kg for Zn, Fe, Cu, and Pb, respectively. There were significant negative correlations (lowest; r = -0.24, p < 0.01, n = 30; highest; r = -0.58, p < 0.01, n = 30) between fish tissue metal concentrations and size of fish from Ologe Lagoon. Also, significant positive correlations (lowest; r = 0.48, p < 0.05, n = 30; highest; r = 0.93, p < 0.01, n = 30) between concentrations of Cu in sediment and tissues of O. niloticus were observed. The concentrations of the metals in the tissues of O. niloticus have exceeded the limits recommended by WHO. The maximum safe daily consumption (MSDC) value of Fe in Ologe Lagoon was lower than the recommended average daily intake of fish for humans. This indicated that O. niloticus from Ologe Lagoon may not be safe for human consumption. Therefore, there is a need for regular monitoring of heavy metal in these water bodies and enforcement of existing laws on the treatment of effluent before they are discharged into aquatic ecosystems.

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Electro-concentration of nutrients from waste streams is a promising technology to enable resource recovery, but has several operational concerns. One key concern is the formation of inorganic scale on the concentrate side of cation exchange membranes when recovering nutrients from wastewaters containing calcium, magnesium, phosphorous and carbonate, commonly present in anaerobic digester rejection water. Electrodialytic nutrient recovery was trialed on anaerobic digester rejection water in a laboratory scale electro-concentration unit without treatment (A), following struvite recovery (B), and following struvite recovery as well as concentrate controlled at pH 5 for scaling control (C). Treatment A resulted in large amount of scale, while treatment B significantly reduced the amount of scale formation with reduction in magnesium phosphates, and treatment C reduced the amount of scale further by limiting the formation of calcium carbonates. Treatment C resulted in an 87 ± 7% by weight reduction in scale compared to treatment A. A mechanistic model for the inorganic processes was validated using a previously published general precipitation model based on saturation index. The model attributed the reduction in struvite scale to the removal of phosphate during the struvite pre-treatment, and the reduction in calcium carbonate scale to pH control resulting in the stripping of carbonate as carbon dioxide gas. This indicates that multiple strategies may be required to control precipitation, and that mechanistic models can assist in developing a combined approach.

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The focus of modelling in wastewater treatment is shifting from single unit to plant-wide scale. Plant-wide modelling approaches provide opportunities to study the dynamics and interactions of different transformations in water and sludge streams. Towards developing more general and robust simulation tools applicable to a broad range of wastewater engineering problems, this paper evaluates a plant-wide model built with sub-models from the Benchmark Simulation Model No. 2-P (BSM2-P) with an improved/expanded physico-chemical framework (PCF). The PCF includes a simple and validated equilibrium approach describing ion speciation and ion pairing with kinetic multiple minerals precipitation. Model performance is evaluated against data sets from a full-scale wastewater treatment plant, assessing capability to describe water and sludge lines across the treatment process under steady-state operation. With default rate kinetic and stoichiometric parameters, a good general agreement is observed between the full-scale datasets and the simulated results under steady-state conditions. Simulation results show differences between measured and modelled phosphorus as little as 4-15% (relative) throughout the entire plant. Dynamic influent profiles were generated using a calibrated influent generator and were used to study the effect of long-term influent dynamics on plant performance. Model-based analysis shows that minerals precipitation strongly influences composition in the anaerobic digesters, but also impacts on nutrient loading across the entire plant. A forecasted implementation of nutrient recovery by struvite crystallization (model scenario only), reduced the phosphorus content in the treatment plant influent (via centrate recycling) considerably and thus decreased phosphorus in the treated outflow by up to 43%. Overall, the evaluated plant-wide model is able to jointly describe the physico-chemical and biological processes, and is advocated for future use as a tool for design, performance evaluation and optimization of whole wastewater treatment plants.

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ResumenLas diatomeas del bentos son el componente más estudiado del perifiton en los ríos de Costa Rica, sin embargo aún queda mucho por conocer sobre su ecología. Por eso en el presente estudio se analizó el perifiton en seis diferentes sitios en la cuenca medio del Río Sarapiquí en el 2010, 2011 y 2012. En cada uno de los muestreos se realizó el conteo de 400 frústulas, de las cuales se obtuvo la abundancia relativa de las especies: Achnanthidium exiguum, Coconneis placentula, Cymbella tumida, Luticola goeppertiana, Luticola ventricosa, Navicula symmetrica, Nitzchia clausii, Nupela praecipua, Reimeria sinuata y Synedra goulardi. Esta información fue relacionada con los datos físico químicos (oxígeno disuelto, temperatura, conductividad, total de sedimentos en suspensión, turbidez, pH y alcalinidad) medidos en cada uno de los sitios. Con el propósito de observar las relaciones entre los diferentes sitios dentro de la cuenca, se utilizó un análisis de correspondencia canónica (ACC), lo que permitió distinguir tres sectores de acuerdo a la altitud. Estos sectores se diferencian en el tipo de sustrato, cobertura riparia vegetal y parámetros físico-químicos, lo que propicia diferencias en la composición de especies de diatomeas entre ellos. Se obtuvieron los valores óptimos calculados y tolerancia calculada para cada una de las especies. Los resultados obtenidos indican que las especies: A. exiguum, R. sinuata,L. ventricosa y C. tumida, dominan en aguas limpias, oxigenadas y baja temperatura. Las especies N. praecipua, S. goulardi, C. placentula, L. goeppertiana, N. clausii y N. symmetrica se encuentran en aguas cálidas, alta turbidez y poco oxigenadas. Las especies A. exiguum, R. sinuata, prevalecen en sitios con agua alcalina y baja conductividad y las especies N. symmetrica, C. tumida y L. ventricosa presentan una relación positiva con la conductividad y el pH de las aguas. Las especies estudiadas mostraron buenos indicios de su valor como indicadores de calidad del agua, sin embargo, debido a diferencias de interpretación por varios autores, es necesario realizar más estudios en otras cuencas hidrográficas en el país.

Abstract The tolerance of ten diatom species (Bacillariophyceae) to water's physico-chemical factors in the Sarapiqui River, Costa Rica. Benthic diatoms are the periphyton component most studied in Costa Rican rivers, yet there is still much to be known about their ecology. This study aims to contribute to this knowledge. Periphyton samples from six locations along the middle reach of Sarapiquí river and some of its tributaries were taken and analyzed from 2010 to 2012. A total count of 400 frustules was performed in each sample to obtain relative abundances of each species. Ten species, which were easily recognized at the light microscope, were analyzed here: Achnanthidium exiguum, Coconneis placentula, Cymbella tumida, Luticola goeppertiana, Luticola ventricosa, Navicula symmetrica, Nitzchia clausii, Nupela praecipua, Reimeria sinuata and Synedra goulardi. Their abundance was related to physico chemical data at each site for every sampling date (dissolved oxygen, temperature, conductivity, total suspended solids, turbidity, pH and alkalinity) with a canonical correspondence analysis (CCA) that allowed distinguishing three sectors along the river according to altitude. These sectors differed by substrate, riparian vegetation cover, and physic-chemical parameters, all of which resulted in differences in diatom species composition among them. Optimum values and tolerances form each environmental parameter were calculated for each species. Our results showed that A. exiguum, R. sinuata,L. ventricosa and C. tumida, were dominant in clean and well oxygenated waters with low temperatures. The species N. praecipua, S. goulardi, C. placentula, L. goeppertiana, N. clausii and N. symmetrica inhabited warm waters with high turbidity and low oxygen. The species A. exiguum, R. sinuata were dominant in sites with low alkalinity and conductivity, whereas species like N. symmetrica, C. tumida and L. ventricosa showed a positive relationship with conductivity and pH. The studied species showed good characteristics of their value as water quality indicators, yet due to different interpretations by several authors, it is necessary to perform further studies at more river basins in the country. Rev. Biol. Trop. 64 (1): 105-115. Epub 2016 March 01.

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Gangliosides (sialic acid-containing glycosphingolipids) are abundant in neurons of all animal species and play important roles in many cell physiological processes, including differentiation, memory control, cell signaling, neuronal protection, neuronal recovery, and apoptosis. Gangliosides also function as anchors or entry points for various toxins, bacteria, viruses, and autoantibodies. GM1, a ganglioside component of mammalian brains, is present mainly in neurons. GM1 is one of the best studied gangliosides, and our understanding of its properties is extensive. Simple and rapid procedures are available for preparation of GM1 as a natural compound on a large scale, or as a derivative containing an isotopic radionuclide or a specific probe. Great research interest in the properties of GM1 arose from the discovery in the early 1970s of its role as receptor for the bacterial toxin responsible for cholera pathogenesis.

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BACKGROUND: Lentinus edodes is an edible mushroom commonly known as shiitake, which is the second most produced and consumed edible mushroom in the world and is an important nutrient source in the human diet. To fully use L. edodes, the mushrooms are occasionally ground into powder as a flavourful and functional food additive. METHODS: This study produces powders from the cap and stipe of Lentinus edodes mushrooms through superfine grinding. These powders are composed of sub-micron range particles with various size distributions. The superfine grinding process is then compared with shear pulverisation to determine the different effects on both the cap and stipe powders in terms of particle size and physico-chemical, morphological and thermogravimetric properties. RESULTS: When average particle size was reduced to 0.54 and 0.46 µm, respectively, the moisture and protein content, angles of repose and slide, and water holding capacity of the powders decreased to varied extents. However, soluble dietary fibre, water solubility index, and swelling capacity increased. Scanning electron microscope images suggested that the superfine grinding process effectively changed the original surface structure of the L. edodes powders. The curves of thermogravimetric analysis and those of the derivatives of thermogravimetry indicated that superfine grinding can improve the thermostability of L. edodes powders. Furthermore, superfinely ground L. edodes powders may be used as pharmaceutical or food additives in various fields. CONCLUSION: The present study suggests that superfinely ground L. edodes powders may be applied in various fields as pharmaceutical or food additives.

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This study was designed to establish the presence and function of the mucous layer surrounding spores of Bacillus subtilis. First, an external layer of variable thickness and regularity was often observed on B. subtilis spores. Further analyses were performed on B. subtilis 98/7 spores surrounded by a thick layer. The mechanical removal of the layer did not affect their resistance to heat or their ability to germinate but rendered the spore less hydrophilic, more adherent to stainless steel, and more resistant to cleaning. This layer was mainly composed of 6-deoxyhexoses, ie rhamnose, 3-O-methyl-rhamnose and quinovose, but also of glucosamine and muramic lactam, known also to be a part of the bacterial peptidoglycan. The specific hydrolysis of the peptidoglycan using lysozyme altered the structure of the required mucous layer and affected the physico-chemical properties of the spores. Such an outermost mucous layer has also been seen on spores of B. licheniformis and B. clausii isolated from food environments.

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This study deals with the influence of water physico-chemical properties, tides, rainfall and fecal pollution on the abundance of enteropathogens in a main distributary of the Ganges, in the endemic cholera belt of West Bengal. Between January and June 2011, water and sediments were sampled from two sites of the Hooghly River by Kolkata and Diamond Harbour. Counts of cultivable Vibrio (CVC, from~10(2) to~10(5)CFU/L) and total bacteria (TBC, from~10(5) to~10(9)CFU/L) increased with water temperature (17°C to 37°C). A combination of variations in tidal height, salinity and turbidity had a distinct influence on CVC, TBC and coliform counts. At Diamond Harbour, a salinity increase from 0.6 to 7.9 was accompanied by a 1000-fold amplification of initial CVC~10(2)CFU/L, whereas higher prevalence of coliforms in Kolkata was related to greater disposal of untreated sewage into the river. Turbidity-dependent variation of CVC was noteworthy, particularly at Diamond Harbour, where CVC in intertidal surface sediments showed an analogous trend as in surface waters, suggesting bentho-pelagic coupling of Vibrio dynamics. Besides the influence of salinity variation with tidal cycles, sediment re-suspension from tidal flats can play a role on Vibrio abundance in aquatic ecosystems.

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The aim of this work was to study the physicochemical parameters of water quality collected from 12 sampling stations from Topputhurai to Muthupet in Vedaranyam located on the southeast coast of India from January to December 2008. Results showed that the DO and nutrients were the maximum in the Bay of Bengal during the monsoon period. High concentration of the nutrients in summer season was obtained near the Muthupet mangroves compared to the Palk Strait, which showed that this acted as a source of nutrients to the adjacent coastal waters. Low concentrations of the nutrients observed in the monsoon could be attributed to the terrestrial runoff from Muthupet lagoon. The physicochemical characteristics of coastal waters between the Point Calimere and Muthupet could be used as a baseline data for the monitoring, conservation and management of Point Calimere Wildlife and Bird sanctuary, Great Vedaranyam swamp and Muthupet mangrove ecosystem.