Achievements in the Life Sciences最新文献

The determination of 4-nonylphenols has been developed using HPLC with fluorescence detection method. 4-Nonylphenols in sea water samples were extracted using a liquid–liquid extraction. Acidification and adding salting-out agents (NaI) of water samples increased the extraction degree. The extraction of 4-nonylphenols was done twice with 20 mL of methylene chloride. The applied concentrated range was over 5–1000 ng/mL for the 4-nonylphenol. The recovery test ranged from 78.5 to 89.9% with relative standard deviations between 1.0 and 7.5% of 100 ng/mL of the standard phenols spiked with the water sample and the detection limit was 1 ng/mL. The proposed method was applied satisfactorily for the determination of 4-nonylphenole in sea water samples. Levels of 4-nonylphenol were determined in the sea waters of the Amur Bay. Water samples were collected every year from 2008 to 2015. Concentrations of 4-nonylphenol in the waters ranged from levels below the detection limits up to 1.24 μg/L.

The gene of tyrosylprotein sulfotransferase, which was discovered in mammals, has been widely found in marine mollusk Littorina sitkana. High conservation of this gene indicates the functional importance of TPST in the metabolism of the living world. The cDNA encoding TPST in the mollusk was cloned and sequenced, and the enzyme was assigned on the basis of amino acid sequence similarity as tyrosylprotein sulfotransferase-2 (TPST-2). The putative homology model for the catalytic domain of TPST from L. sitkana was constructed according to crystal structure of the catalytic domain of the human TPST-2. The putative model of dimer structure showed that the active site involved two monomers and the dimer contains two active centers.

Feeding methods and habits of brown bear in Sikhote-Alin are varied and specific for each type of feeding behavior depending on the composition and condition of food, its availability and abundance, season, animal's sex, age, physical condition, personal preferences and experience, the presence of competitors and disturbance from other predators and humans. A feature of the feeding behavior of bears in Sikhote-Alin is consumption of the remains of meals of tigers.

This study was designed to evaluate the hepatoprotective activity of aqueous extract and isolated flavone (5-hydroxy, 7,8, 2’trimethoxy flavone) compound of Andrographis alata against CCl₄ induced hepatotoxicity. The hepatotoxicity was induced in albino rats CCl₄ (i.p.). Analysis of serum ALT, AST and alkaline phosphatase activities with the concentrations of albumin, total protein and bilirubin was carried out. The activities of all the marker enzymes reported a significant elevation in CCl₄ treated rats, which were significantly recovered towards an almost normal level in animals simultaneously administered with aqueous extract and flavone compound. This work suggests that aqueous extract and isolated flavone compound of A. alata exert significant therapeutic effect on CCl₄ induced hepatotoxicity in rats.

The use and commercial applications of biosurfactants in the petroleum industries have been raised during the past decades. Marine bacteria and their efficiency in crude oil recovery has been less studied than terrestrial strain, hence this present study. A novel marine bacterium Bacillus simplex having promising biosurfactant production was isolated from a petroleum hydrocarbon-contaminated coastal sea sediment samples of Nagapattinam fishing harbor, Tamil Nadu, India. This strain showed most economical biosurfactant production with an agro-industrial waste substrate, sunflower oil cake at 54th h time incubation along with the cultural conditions of 20 ppt salinity, 35 °C temperature, and pH 7. The produced biosurfactant was purified, which was accounted at 908 ± 7 mg/L on dry weight basis. The biosurfactant was identified as lipopeptide with a molecular mass of 1111.1 Da which was deduced using TLC, biochemical estimation methods, FT-IR, NMR, and MALDI-TOF MS analysis. Furthermore, this purified lipopeptide surfactant showed consistent and enhanced crude oil recovering efficiency under different salinity conditions (0–30%). Based on the above facts, the isolated novel marine bacterium proved its cheaper production of novel biosurfactant and its promising oil recovering efficiency even at hypersaline conditions. Further, this is the first report of a biosurfactant from the bacterium Bacillus simplex.

The characteristics of four stages of demutational succession of a valley Korean pine–broadleaf forest are provided according to the parameters most vividly capturing the structure of the plant community and influencing the renewal and mycorrhization of Korean pine (Pinus koraiensis) seedlings. It was found that Korean pine seedlings grow in a competitive environment on the fresh burned site; hence the mycorrhization occurs from specialized symbiotes that provide competitive advantages and adaptation to stress factors. Mycorrhiza forms the least successful in the 50–60-year-old larch–birch–spiraea association during the seral stages of succession. The 90–100-year-old birch–broadleaf association offers the most suitable soil and cenotic conditions for the development of Korean pine seedlings that can successfully generate mycorrhiza from both the spores present in the thick soil layer, and through mycelia of shared mycorrhizal networks of seral and primary (including Korean pine) tree species. A 230–250-year-old climax community comprises all patterns to ensure that pine seedlings encounter a fungal component; in this community the greatest abundance of species and a balanced composition of ectomycorrhizal fungi communities of Korean pine are observed.

Trichophyton soudanense and Trichophyton mentagrophyte were isolated from the rice mill environment, cultured, and used singly and as co-culture in the treatment of measure quantities of pre-heated rice husk. Carboxymethyl cellulase activity of 57.61 μg/ml/min was optimum for T. mentagrophyte-treated rice husk crude enzymes at 50 °C and 80 °C, respectively. The duration of 120 h gave the highest CMCellulase activity of 75.84 μg/ml/min for crude enzyme of T. mentagrophyte heat-pretreated rice husk. The duration of 96 h gave maximum activity of 58.21 μg/ml/min for crude enzyme of T. soudanense heat-pretreated rice husk. Highest CMCellulase activities of 67.02 μg/ml/min and 69.02 μg/ml/min at pH of 5 were recorded for crude enzymes of monocultures of T. soudanense (TS) and T. mentagrophyte (TM) heat-pretreated rice husk. Heating before treatment with T. mentagrophyte gave 44.50 ± 10.90 cellulose as maximum, total lignin value of 28.90 ± 1.80 from co-culture of T. soudanense and T. mentagrophyte (TS + TM), hemicellulose content of 30.50 ± 2.12 (% ± SEM) from pre-heated rice husk treated with T. soudanense (TS), carbohydrate content of 16.79 ± 9.14, and reducing and non-reducing sugar values of 2.66 ± 0.45 and 14.13 ± 8.69 were all obtained from for pre- heated rice husk treated with T. mentagrophyte (TM). The pre-heated rice husk treated with T. mentagrophyte (TM) fermented with palm wine yeast gave bioethanol value of 11.11 ± 0.21 (% ± standard deviation) as the highest yield.

Three types of vegetable oils namely, groundnut oil, coconut oil and palm kernel oil were investigated in this study for their clearing ability in wood histology. The vegetable oils were compared with the conventional clearants like xylene and clove oil. Using a Riechet microtome sliding machine, sections of wood that were about 20 μm were prepared and cleared in each of the oils. Under a light microscope, the results showed that sections cleared in the vegetable oils did not show any sign of distortion as details of wood features were distinct and clear after processing in the vegetable oils. The study concluded that the vegetable oils could be used as substitutes for xylene and clove oil. The respective photo micrographs are hereby presented showing their efficacy after slide preparation. On the accounts of health hazards and cost of conventional clearing agents, the study also recommended groundnut oil, coconut oil and palm kernel oil as alternative clearants in wood histological processes.

Chlorella vulgaris was isolated from sewerage treatment plant and grown in the presence of sodium bicarbonate as carbon source at 0.25, 0.5 and 1.0 g L^− 1. Highest specific growth rate (0.653 μ d^− 1) was obtained with 1 g L^− 1 bicarbonate followed by 0.5 g L^− 1 (0.641 d^− 1) on 15th day culturing. Total chlorophyll content of microalgae has increased in a dose dependent fashion with bicarbonate addition and maximum level recorded in 1 g L^− 1 (0.769 ± 0.09 g L^− 1). The biomass productivity was in the range of 0.237–0.996 g d^− 1 L^− 1. Rate of CO₂ fixation and carbon content, in terms of quantity was estimated. Results showed that at 1 g L^− 1 sodium bicarbonate concentration, maximum CO₂ fixation (0.497 g/dry weight) and carbon content (0.69 g mL^− 1 day^− 1) was found. Biomass concentration was significantly higher (p < 0.05) in cultures (1.54 g L^− 1) supplemented with 1 g L^− 1 bicarbonate whereas there was no much difference in cellular lipid concentration (16 mg mL^− 1). GC–MS analysis of fatty acids showed highest amounts of palmitic acid, myristic and stearic acid. In summary, the addition of sodium bicarbonate increases cellular abundance, chlorophyll content and to some extent in the case of lipid content in C. vulgaris integrated with CO₂ sequestration.

Over the last decade, much interest has been developed in biopolymer based materials due to their biocompatible, biodegradable, non-toxic and non-allergenic nature. Chitosan is a unique biopolymer that exhibits outstanding properties, besides biocompatibility and biodegradability. Most of these peculiar properties arise from the presence of primary amines along the chitosan backbone. Many works have been done to obtain chitosan based scaffolds, including surface modifications, the fabrication of chitosan based blends, chitosan based composite scaffolds, and drug-loaded scaffolds. This study provides an overview of the key features of inherent properties of chitosan, their modification, and its use in biomedical engineering particularly toward anti-inflammatory and wound healing.