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101.
Kraft lignin (KL) is a renewable source of many valuable intermediate biochemical products currently derived from petroleum. An excessive of lignin comes from pulping wastewater caused an adverse pollution problems hence affecting human and aquatic life. A comprehensive study pertaining to emulsion liquid membrane (ELM) extraction of lignin from pulping wastewater was presented. ELM formulation contains Aliquat 336 as carrier, kerosene as diluent, sodium bicarbonate (NaHCO3) as stripping agent and Span 80 as surfactant. The emulsion stability was investigated at different surfactant concentrations, homogenizer speed and emulsification time. Modifier (2‐ethyl‐1‐hexanol) was added to avoid segregation of third phase while improving the emulsion stability. At optimum conditions, 95% and 56% of lignin were extracted and recovered, respectively at 10 min of extraction time, 0.007 M of Aliquat 336, 0.1 M of NaHCO3 and 1:5 of treat ratio. Additional of modifier was contributed to highest recovery up to 98%. The ELM process was found to be equally feasible and quite effective in the recovery of KL from real pulping wastewater. Therefore, ELM process provides a promising alternative technology to recover KL from pulping wastewater while solving the environmental problems simultaneously. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1305–1314, 2015  相似文献   
102.
The enterovirus (EV) types echovirus (E-) 5, E-9, and E-18, and coxsackievirus (CV-) A9 are infrequently reported in human diseases and their epidemiologic features are poorly defined. Virus transmission patterns between countries have been estimated with phylogenetic data derived from the 1D/VP1 and 3CD gene sequences of a sample of 74 strains obtained in France (2000–2012) and Tunisia (2011–2013) and from the publicly available sequences. The EV types (E-5, E-9, and E-18) exhibited a lower worldwide genetic diversity (respective number of genogroups: 4, 5, and 3) in comparison to CV-A9 (n = 10). The phylogenetic trees estimated with both 1D/VP1 and 3CD sequence data showed variations in the number of co-circulating lineages over the last 20 years among the four EV types. Despite the low number of genogroups in E-18, the virus exhibited the highest number of recombinant 3CD lineages (n = 10) versus 4 (E-5) to 8 (E-9). The phylogenies provided evidence of multiple transportation events between France and Tunisia involving E-5, E-9, E-18, and CV-A9 strains. Virus spread events between France and 17 other countries in five continents had high probabilities of occurrence as those between Tunisia and two European countries other than France. All transportation events were supported by BF values > 10. Inferring the source of virus transmission from phylogenetic data may provide insights into the patterns of sporadic and epidemic diseases caused by EVs.  相似文献   
103.
104.
Eleven taxa including one new species of gammaridean amphipods are reported from the waters of Pulau Tioman. The presence of Tethygeneia sunda sp. n. represents the first record of the genus from the South China Sea. Additional material of Ampelisca brevicornis (Costa, 1853); Cymadusa vadosa Imbach, 1967; Paradexamine setigera Hirayama, 1984; Ericthonius pugnax (Dana, 1853); Leucothoe furina (Savigny, 1816); Microlysias xenokeras (Stebbing, 1918); Monoculodes muwoni Jo, 1990 are identified from the South China Sea, supporting previous records by Lowry (2000), Huang (1994), Imbach (1967), Margulis (1968) and Nagata (1959). Three additional species, Gitanopsis pusilla K.H. Barnard, 1916, Liljeborgia japonica Nagata, 1965b and Latigammaropsis atlantica (Stebbing, 1888), whilst previously reported from the neighbouring waters, comprise new records for the South China Sea.  相似文献   
105.
The protective effect of the synthetic aminothiol, N-(2-mercaptopropionyl) glycine (MPG) on adriamycin (ADR) induced acute cardiac and hepatic oxidative toxicity was evaluated in rats. ADR toxicity, induced by a single intraperitoneal injection (15 mg/kg), was indicated by an elevation in the level of serum glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), creatine kinase isoenzyme (CK-MB), and lactic dehydrogenase (LDH). ADR produced significant elevation in thiobarbituric acid reactive substances (TBARS), indicating lipid peroxidation, and significantly inhibited the activity of superoxide dismutase (SOD) in heart and liver tissues. In contrast, a single injection of ADR did not affect the cardiac or hepatic glutathione (GSH) content and cardiac catalase (CAT) activity but elevated hepatic CAT. Pretreatment with MPG, (2.5 mg/kg) intragastrically, significantly reduced TBARS concentration in both heart and liver and ameliorated the inhibition of cardiac and hepatic SOD activity. In addition, MPG significantly decreased the serum level of GOT, GPT, CK-MB, and LDH of ADR treated rats. These results suggest that MPG exhibited antioxidative potentials that may protect heart and liver against ADR-induced acute oxidative toxicity. This protective effect might be mediated, at least in part, by the high redox potential of sulfhydryl groups that limit the activity of free radicals generated by ADR.  相似文献   
106.
Mammalian and hepatic aspartate transcarbamylase is inhibited by phenobarbital p-nitrophenylhydra-zone in a reversible and non-competitive type with Ki values 8.45 × 10?5 and 9.64×10?5 M in the reactions toward carbamyl phosphate and aspartate, respectively. In vivo inhibition occurred in a dose-dependent manner in which less than 50% of the activity was retained. These observations suggest that this inhibitor may interfere with the in vivo regulation of this enzyme and lead to an additional biological effect of phenobarbitals.  相似文献   
107.
Aedes albopictus larvae obtained from different types of agricultural and non-agricultural localities in Peninsular Malaysia were subjected to several larvicides at World Health Organization (WHO) recommended dosages. Upon 24 h of WHO larval bioassay using two organochlorines and six organophosphates, high resistance against dichlorodiphenyltrichloroethane (DDT), temephos, chlorpyrifos and bromophos were demonstrated among all larval populations. Aedes albopictus larvae from both paddy growing areas (92.33% mortality) and rubber estates (97.00% mortality) were moderately resistant to dieldrin while only Ae. albopictus larvae from dengue prone residential areas (89.00% mortality) showed high resistance against dieldrin. All Ae. albopictus larval populations also developed either incipient or high resistance to both malathion (33.67%–95.33% mortality) and fenitrothion (73.00%–92.67% mortality). Only Ae. albopictus larvae from fogging-free residential areas that were tolerant to fenthion (97.33% mortality), whereas Ae. albopictus larvae from dengue prone residential areas were highly resistant to the same organophosphate (88.33% mortality). Cross resistance between intraclass and interclass larvicides of organochlorines and organophosphates were also exhibited in this study. The present study provided baseline data on various susceptibility levels of Ae. albopictus larval populations from different types of agricultural and non-agricultural localities against organochlorines and organophosphates at WHO recommended dosages. Nevertheless, further susceptibility investigations are suggested using revised doses of larvicides established from the local reference strain of Ae. albopictus to prevent the underestimation or overestimation of insecticide resistance level among Ae. albopictus field strains of larvae.  相似文献   
108.
This study examined the possible protective effects of thymoquinone (TQ), the main constituent of the volatile oil of black seed (Nigella sativa), against cyclophosphamide (CP)-induced cardiotoxicity. Adult male Wistar albino rats were divided into four treatment groups. Rats in the first group were served as control. Rats in the second group received TQ (50 mg/L in drinking water) for 12 days. Animals in the third group were injected with a single dose of CP (200 mg/kg, IP) at day 5. Rats in the fourth group received TQ (50 mg/L in drinking water) for 5 days before a single dose of CP (200 mg/kg, IP) and continued thereafter throughout the experiment. On day 13, animals were sacrificed; serum and hearts were isolated and analyzed. Cyclophosphamide resulted in a significant increase in serum creatine kinase, lactate dehydrogenase, cholesterol, triglycerides, creatinine, urea, and tumor necrosis factor-α. In heart tissues, CP resulted in a significant increase in thiobarbituric acid reactive substances and total nitrate/nitrite and a significant decrease in reduced glutathione, glutathione peroxidase, catalase, and adenosine triphosphate levels. Interestingly, TQ supplementation resulted in a complete reversal of all the biochemical changes induced by CP to their control values. Data from this study suggest that TQ supplementation attenuates CP-induced cardiotoxicity by a mechanism related, at least in part, to its ability to decrease oxidative and nitrosative stress and to preserve the activity of antioxidant enzymes as well as its ability to improve the mitochondrial function and energy production. .  相似文献   
109.
Leptin and μ-calpain have been considered as two candidate genes for carcass performance and meat quality traits in the farm animals. The micromolar calcium-activated neutral protease (CAPN1) gene encodes μ-calpain that degrades myofibril proteins under the postmortem conditions which appears to be the primary enzyme in the postmortem tenderization process. Leptin is the hormone product of the obese (LEP) gene. The role of leptin as a lipostatic signal regulating whole-body energy metabolism makes it one of the best physiological markers of body weight, food intake, reproduction and immune system functions.Genomic DNA extracted from 100 healthy buffaloes was amplified using primers that were designed from the cattle CAPN1 and LEP gene sequences. The amplified fragments of CAPN1 obtained from all tested buffalo DNA at 670-bp were digested with FokI endonuclease. The result showed that all tested buffaloes are genotyped as CC for CAPN1. For LEP gene, the amplified fragments obtained from all tested buffalo DNA at 400-bp were digested with Sau3AI endonuclease. All buffalo animals investigated in the present study are genotyped as AA for LEP gene.  相似文献   
110.
This context was investigated to assess the in vitro antioxidant, anti-diabetic, anti-obesity, and angiotensin-converting enzyme (ACE) inhibition traits of Punica granatum fruits peel extract. Initially, among various extracts tested, aqueous and ethanolic peel extracts depicted the presence of diverse phytoconstituents. In vitro antioxidative properties of peel extracts were determined using standard methodologies. Results showed that aqueous and ethanolic extracts had IC50 values of 471.7 and 509.16 μg/mL, respectively in terms of 1,1,diphenyl 2,2,picrylhydrazyl scavenging. Likewise, IC50 values of aqueous and ethanol extract were obtained as 488.76 and 478.47 μg/mL towards the degradation of hydrogen peroxide. The ethanolic extract exhibited the highest inhibition of α-glucosidase by showing activity of 53.34 ± 2.0 to 15.18 ± 1.4 U/L in a dose dependent manner (100–1000 µg/mL). Ethanolic extract was reported as the most active inhibitor of lipase with an IC50 value of 603.50 µg/mL. Ethanolic extract showed increased inhibition of ACE in a concentration dependent manner (100–1000 µg/mL) with IC50 value of 519.45 µg/mL. Fourier transform-infrared spectrum revealed the availability of various functional groups in the ethanolic extract of peel. Gas chromatography-mass spectrometry chromatogram of peel extract illustrated 23 diversified chemical constituents including 1,2,3,4-butanetetrol, Dimethyl sulfone, 9-octadecenamide, and Pentadecanoic acid as predominant compounds. In summary, P. granatum fruits peel extract revealed promising antioxidant, anti-diabetic, anti-obesity, and anti-hypertensive properties.  相似文献   
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