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1.

Synthesis Polysulfone-Acetylethanol Ultrafiltration Membranes. Application to Oily Wastewater Treatment Martin Alberto Masuelli Journal of Materials Physics and Chemistry. 2013 1 (3). doi: 10.12691/jmpc-1-3-3 Keywords: polysulfone-COEtOH, membrane, Characterization , oily wastewater Context: Chemical functionalization of polymers after the synthesis of membranes has great importance for various applications separative processes of industrial or environmental interest. Polysulfone (PSf) is one of the most applied polymers for separative processes used especially in membrane technology, due to its excellent chemical, mechanical and thermal properties. The functionalization of PSf makes it very attractive to give special characteristics due to their high hydrophobicity and membrane fouling fast. In this work PSf perform functionalization by the method of Friedel-Crafts with choroethyl chloroacetate and subsequent hydrolysis of chloroetyl group (-OH). After synthesizing the membrane is characterized by FT-IR ATR spectroscopy, 1HNMR, contact angle measurements, retention of polydisperse solutes and hydraulic permeability. Finally, the membranes tests fouling are performed with an oily wastewater emulsion. The fouling tests showed that the functionalized PSf membrane demonstrated significant anti-fouling property, suggesting the remarkable benefit for long-term operation in practical applications. Specifically, all the functionalized membranes reached almost 60% water flux recovery and were able to maintain the constant initial fluxes in filtration test, whereas the raw membrane only recovered 70.27% and suffered continuous decline. This promotion might be related to the increase of membrane surface hydrophilicity. Abstract Full Text (PDF) [Epub] Full Text (HTML)

2.

Phenotyping Groundnut Rhizobia Native to Phosphorus Deficient Soils in Western Kenya Velma Okaron, Beatrice A. Were, Benson O. Nyongesa American Journal of Microbiological Research. 2017 5 (1). doi: 10.12691/ajmr-5-1-3 Keywords: legume nodulating bacteria, Characterization , phosphorus deficiency, arachis hypogaea, inoculants Context: Most soils in western Kenya are characterized by high acidity level and phosphorus (P) deficiency, which affect nodulation and nitrogen fixation of groundnut (Arachis hypogaea L.). This study aimed at characterising rhizobia capable of nodulating groundnut in P deficient soils in Western Kenya. Sixty four isolates out of the 68 were confirmed to be rhizobia due to their ability to nodulate groundnut. Ninety six percent of the isolates exhibited semi-globose to globose colony shape on yeast extract mannitol agar (YEMA). Groundnut was nodulated by both fast and slow growing rhizobia isolates with 81% being fast growers. Fifty one isolates representing 75% produced acid on YEMA medium supplemented with bromothymol blue (BTB). The isolates varied in their response to pH with 39 and 61 growing at pH 4.0 and 5.5, respectively. All the isolates grew at pH 7.0 and 8.5. YEMA medium containing glucose, sucrose, starch and citrate had 64, 61, 56 and 5 isolates growing, respectively. Sixty four isolates exhibited clear zone of solubilization on medium containing dicalcium phosphate as source of inorganic phosphate. Solubilization index (SI) varied from 1.1 to 6.8. Fast-growing rhizobia isolates N01, B02, I06, Q01, F05, C02, E01, Q03, I01 and B01 recorded the highest solubilization index of 3.8, 4.5, 4.6, 4.6, 4.7, 5.0, 5.1, 6.1, 6.1 and 6.8, respectively. Groundnut rhizobia showed variation in their potential to solubilize inorganic phosphate and effectively nodulate the host. The most promising isolates from this study would be used as bio-fertilizer upon further validation in the greenhouse and field. Abstract Full Text (PDF) [Epub] Full Text (HTML)

3.

Screening of Terpene Lactones and Flavonoid Glycosides in gingko biloba Capsule by UPLC- Orbitrap High Resolution MS, with Emphasis on Isomer Differentiation Haiyun Zhou, Weiquan Tang, Jin Zeng, Chengfang Tang Journal of Food and Nutrition Research. 2014 2 (7). doi: 10.12691/jfnr-2-7-7 Keywords: gingko biloba, terpene lactones, gingko biloba glycosides, glycoside fragment ions, structure Characterization , UPLC-LTQ-Orbitrap MS Context: In present study, a method basing on accurate mass and fragmentation pattern was designed to screen the terpene lactones and flavonoids in the methanol extract of Ginkgo biloba capsule powder. An UPLC with a hybrid linear ion trap – orbitrap mass spectrometer (UPLC-LTQ-Orbitrap Elite) was used. The chromatographic analysis of the sample was performed on a C18 column (100 × ID, particle size 1.9 μm) with gradient elution using methanol and water with 0.10% formic acid. Mass spectrometry was performed in the negative ESI mode. By comparison the accurate mass, element composition and fragment pattern, twenty-six compounds were identified, including 5 ginkgo terpene lactones (bilobalide, ginkgolide A, B, C and J) and 21 flavonoid glycosides. The major glycosides identified included: kaempferol-3-O-glu-glu-rha, kaempferol-7-O-rutinoside, isorhamnetin-3-O-rutinoside, kaempferol-3-O -rha-glu, quercetin-3-O- glucoside, kaempferol-3-O-rha-glu-coumaroyl and -methoxymyricetin-3-O-rutinoside. The structural isomers were differentiated through the characteristic ions obtained from their MS/MS spectra. In addition, a compound 3,5,-trihydroxyflavone-3-O-glucoside, which was not reported in G. biloba before to our knowledge, was identified in the extract. The fragmentation pathways and characteristic product ions of flavonoid glycosides were shown and summarized for the rapid identification. The developed method was proved to be useful and precise for fast qualitative analysis of flavonoid compounds in mixture. Abstract Full Text (PDF) [Epub] Full Text (HTML)

4.

Geotechnical Properties and Geochemical Composition of Mudrock from the Douala Sub Basin, Cameroon: Implication for Industrial Potentials Ndengwe Alexander Tangwa, Njoh Oliver Anoh, Nowel Yinkfu Njamnsi Journal of Geosciences and Geomatics. 2022 10 (3). doi: 10.12691/jgg-10-3-5 Keywords: Mudrock, clay mineral, Characterization , valorisation, Douala Sub basin Cameroon Context: The geotechnical and compositional characteristics of mudrock deposits in the Douala Sub basin were investigated using a combination of analytical methods, including particle size distribution, Atterberg limits, mineralogical (X-ray diffraction) analyses, and whole rock geochemistry. The goal is to characterize the nature and physicochemical properties of mudrock in order to determine its applicability in industries. Grain size analysis reveals that clay-sized particles dominate the samples, with a plasticity index ranging from 6.8% to 20.67%. The mudrock materials are primarily composed of kaolinite (16.8-49.4%), quartz (15.8-68.9%), and illite (00-15.3%), which are typical of the Douala Sub- basin sedimentary environment and morphoclimatic conditions. SiO2 (42.77-73.5%) and Al2O3 (13.13-29.98%) are the most abundant oxides in the samples. Iron oxide content is moderate (1.73- 17.18%). Methylene blue values range from 1.12 to 6.95, confirming the clay content of (39.43-45.43%) and also attesting that the sediments in the study area are rich in 1:1 clay. They are suitable for ceramic applications such as (refractory bricks and tiles) and pottery due to the physicochemical parameters associated with mineralogical and geochemical data Abstract Full Text (PDF) [Epub] Full Text (HTML)

5.

Biochemical and Microbiological Characteristics of Raw Milk and Curdled Milk Originated from the Central Region of Burkina Faso Clarisse S. COMPAORE, Fidèle W. TAPSOBA, Charles PARKOUDA, René KOMPAORE, Romaric G. BAYILI, Bréhima DIAWARA, Aly SAVADOGO, Lene JESPERSEN, Hagrétou SAWADOGO-LINGANI American Journal of Food and Nutrition. 2021 9 (1). doi: 10.12691/ajfn-9-1-2 Keywords: raw milk, curdled milk, Characterization , Lactic acid bacteria, Burkina Faso Context: Milk and dairy products play an important role in human nutrition in Burkina Faso as in several developing countries. This study aimed to describe the curdled milk process in the Central region of Burkina Faso through a monitoring of the production and to study the biochemical and microbiological characteristics of raw milk and curdled milk. Microbiological and biochemical characteristics of the products were determined using standard methods. Biodiversity of lactic acid bacteria in curdled milk was determined using (GTG) 5-PCR and 16S rRNA gene sequencing. Processing of curdled milk takes place in calabashes or plastic containers, without heat treatment of raw milk. The fermentation is spontaneous and lasts for 24 - 48 h at ambient temperature. Biochemical analysis showed a low mean pH of curdled milk (4.34 ± 0.10) compared to that of raw milk (6.47 ± 0.02). Dry matter (DM), protein and lipid contents were respectively 7.85%; 16.96 g/L DM and 37.11 g/L DM for raw milk while those of curdled milk were 15.85%; 20.85 g/L DM and 27.03 g/L DM. An increase from 0.22 to 0.37 g/L DM of phosphorus and from 1.10 to 2.46 of calcium was observed with the fermentation. However, iron and zinc contents obtained were 0.55 mg/L DM and 1.97 mg/L DM for raw milk and 0.27 mg/L and 1.6 mg/L for curdled milk, respectively. Microbiological analyzes indicated a high number of aerobic mesophilic bacteria for raw milk (1.9. 107 UFC/mL) as for curdled milk (3.9. 108 UFC/mL). In addition, Enterobacteriaceae counts from raw milk and curdled milk were higher than the acceptable limit of 102 CFU/mL for dairy products. Lactobacillus fermentum, Enterococcus durans/feacium, Lactococcus lactis, Lactobacillus helveticus and Enterococcus feacalis were the predominant species identified in the curdled milk. Abstract Full Text (PDF) [Epub] Full Text (HTML)

6.

Study on Effect Elements of Exopolysaccharide Production of Lactobacillus Kimchi SR8 and DPPH Radical Scavenging Activity Yulong Zhang, Ping Hu, Min Fan, Qianwei Liao Journal of Food and Nutrition Research. 2017 5 (12). doi: 10.12691/jfnr-5-12-8 Keywords: Characterization , exopolysaccharide, free radical, scavenging activity, relationship Context: The correlation between exopolysaccharide production of Lactobacillus kimchi SR8 under different culture conditions and the DPPH radical scavenging activity of exopolysaccharide was studied. Lactobacillus kimchi SR8 produced 228.24 ± 2.23 mg/L exopolysaccharides with sucrose as the carbon source, Beef Extract-Peptone (2:1) as the nitrogen source and an initial pH of 6.50, whilst the DPPH radical scavenging activity of exopolysaccharides was only 6.85% ± 0.77% at a concentration of 0.20 mg/mL. However, the strain produced 206.79 ± 2.23 mg/L exopolysaccharides with glucose as the carbon source, Peptone-Tryptone (1:1) as the nitrogen source and an initial pH of 7.00, and the DPPH radical scavenging activity of exopolysaccharides increased to 28.34% ± 0.32% at the same concentration. The results showed no correlation between the exopolysaccharide production of lactic acid bacteria and the DPPH radical scavenging activity of exopolysaccharide. Therefore, the antioxidant activity should be taken into consideration when measures are taken to increase exopolysaccharide production if greater antioxidant activity of exopolysaccharides is preferred. Abstract Full Text (PDF) [Epub] Full Text (HTML)

7.

Soil-structure Interaction Taken into Account in Characterizing the Behavior of Flexible Piles Cheikh Ibrahima TINE, Oustasse Abdoulaye SALL, Déthié SARR, Aida Ndiouck FAYE, Papa Abdourahmane FALL American Journal of Mechanical Engineering. 2024 12 (2). doi: 10.12691/ajme-12-2-1 Keywords: Flexible pile, Characterization , Soil-structure interaction, Analytical calculation, Numerical modeling Context: The aim of this study is to gain a better understanding of the behavior of flexible piles subjected to lateral loading and head moment in clay soil, taking into account soil-structure interaction. In order to establish the behavioral model of the assembly, soil-pile interaction models according to different authors were presented. According to several authors, the soil-pile interface is characterized by the soil reaction modulus Es. This parameter, which characterizes the interaction between the soil and the structure, depends not only on the mechanical and geometric properties of the concrete and the foundation soil. In this context, the model of was used to characterize Es, which is a function of the rheological parameters of the soil (α and EM) and the geometric characteristics of the pile. After establishing and solving the behavior model of the rigid soil-pile assembly, the Python programming tool was used to perform the parametric analysis. The results show the significant impact of the interaction model adopted. The analysis also shows that the soil pressure modulus, soil slenderness and pile head forces are more influential than the other model parameters. Abstract Full Text (PDF) [Epub] Full Text (HTML)

8.

Molecular Studies on E.coli Isolate from Milk of Mastatic Cattle with Special Reference to Associated Biochemical Changes in Kaliobea Governorate Mervat E.I. Radwan, Khiary Farouk Abo-Zaid American Journal of Infectious Diseases and Microbiology. 2017 5 (3). doi: 10.12691/ajidm-5-3-4 Keywords: mastitis, serotyping Characterization , PCR and biochemical alteration Context: This investigation was performed in Teaching hospital and farm of Benha university in Moshtohor the number of cows in this farm 80 dairy cows that 40 of them had clinical signs of mastitis (inflammation in teats, pain in milking and milk decrease in amount and quality). When examine these cows to identify the disease which cause these signs. California Mastitis Test (CMT) was performed to determine positive milk samples in the Mastitic targeted cows. 20 samples of early lactation stage cows out of 40 samples recovered from CMT- positive milk samples. Biochemical and PCR tests were performed to isolates E. Coli from positive milk samples (CMT) and determined three virulance genes, eae gene, SXT1 and SXT2. The significance of Escherichia coli-induced mastitis and biochemical changes associated to it in cows, due to the presence of virulence genes and wide range resistance to 20 antimicrobials, is concluded. E.coli cause biochemical changes in mastatic cow as (liver enzymes AST, GPT, TP, ant. oxidative enzymes as CAT, SOD, GST, LD and kidney function as urea and creatinine. E.coli has effect on inflammatory response in immunity system of mastitic cow by increase IL6, TNF and CRP. Abstract Full Text (PDF) [Epub] Full Text (HTML)

9.

Physicochemical Composition of Seed Oil of Wild Jojoba Populations in Northwestern Mexico Nidia Araiza-Lizarde, Lilia Alcaraz-Meléndez, Miguel A. Angulo-Escalante, Teodoro Reynoso-Granados, Pedro Cruz-Hernández, Carlos L. Calderón-Vázquez Journal of Food and Nutrition Research. 2017 5 (6). doi: 10.12691/jfnr-5-6-12 Keywords: fatty acid, Characterization , ecotypes, seeds Context: This research analyzed physicochemical parameters of lipids, as well as the fatty acid profile and diversity of three jojoba ecotypes of northwestern Mexico. Oil content was from 43 to 49% in the three ecotypes; iodine value ranged from 82.08 to 83.11 g / 100 g; acidity value was 0.33 to 0.39 mg KOH/g. The four most abundant fatty acids in the three ecotypes were eicosanoic (52-62.43%), oleic (13.80-27.36%), 13-docosanoic (5.25-9.45%), and palmitic (6.43-9.70%) acids. The Inter Simple Sequence Repeat (ISSR) analysis showed that polymorphic accessions were 83%. The ecotypes analyzed in this study represent an alternative for selection and conservation of wild germplasm; furthermore, they also represent a potential for their use in cosmetics and biodiesel manufacturing industries. Abstract Full Text (PDF) [Epub] Full Text (HTML)

10.

Influence of Alcoholic Strength on Sensory Profile of Lager Beers Daniel Sancho, Carlos A. Blanco, Cristina Andrés-Iglesias, Isabel Caballero Journal of Food and Nutrition Research. 2021 9 (4). doi: 10.12691/jfnr-9-4-6 Keywords: non-alcoholic beer, beer Characterization , sensory analysis, flavor Context: Non-alcoholic beer is a product whose demand by consumers is growing worldwide, however, it is not well accepted by consumers due to its organoleptic characteristics. Sensory evaluation reflects the flavor profile of a product and, more specifically, profile methods are considered to offer the best current solution to the problem of describing beer flavor. This research aimed to evaluate several sensory attributes of commercial regular and non-alcoholic beer (low-alcohol and alcohol-free beers) brands. These attributes were carbonation, body, sweetness, bitterness, astringency, flavor persistence, odour and taste. The results obtained by cluster and Principal Components Analysis are in a good consistency. It has been found that non-alcoholic beers have a higher sweetness than regular beers, which may be due to the brewing process. Besides, the study has allowed to determine the organoleptic characteristics of low-alcohol and regular beers. It has also helped to define the sensory profile of low-alcohol beer most valued by consumers in an attempt to improve the sensory properties of this type of beer. Abstract Full Text (PDF) [Epub] Full Text (HTML)