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31.
Nur Fariza Abd. RahmanMahiran Basri Mohd Basyaruddin Abdul RahmanRaja Noor Zaliha Raja Abdul Rahman Abu Bakar Salleh 《Bioresource technology》2011,102(3):2168-2176
Engkabang fat esters were produced via alcoholysis reaction between Engkabang fat and oleyl alcohol, catalyzed by Lipozyme RM IM. The reaction was carried out in a 500 ml Stirred tank reactor using heptane and hexane as solvents. Response surface methodology (RSM) based on a four-factor-five-level Central composite design (CCD) was applied to evaluate the effects of synthesis parameters, namely temperature, substrate molar ratio (oleyl alcohol: Engkabang fat), enzyme amount and impeller speed. The optimum yields of 96.2% and 91.4% were obtained for heptane and hexane at the optimum temperature of 53.9 °C, impeller speeds of 309.5 and 309.0 rpm, enzyme amounts of 4.82 and 5.65 g and substrate molar ratios of 2.94 and 3.39:1, respectively. The actual yields obtained compared well with the predicted values of 100.0% and 91.5%, respectively. Meanwhile, the properties of the esters show that they are suitable to be used as ingredient for cosmetic applications. 相似文献
32.
E. M. Hegazi A. Y. El‐Shazli M. B. Hafez G. M. Abd El‐Aziz 《Archives Of Phytopathology And Plant Protection》2013,46(4):351-360
Series of experiments were undertaken to investigate whether application of Precocene II (PII) to parasitized S. littoralis larvae can influence their THCs and DHCs. PII was applied in single dose treatments (70μg/5 μl/dose). Haemolymph samples were taken at daily intervals from day 3 to day 8 post‐treatments. Two distinct alterations were noted; first, PII‐treatments caused significant decrease in THCs. Once the parasitoid larvae emerge from either treated or untreated hosts, a sharp decline in THCs was observed. The second effect was changes in DHCs of S. littoralis larvae. In controls, haemocyte types could be arranged in descending order due to their relative occurrence into plasmatocytes (PLs), prohaemocytes (PRs), spherule cells (SPs), granular cells (GRs) and oenocytoids (OEs). This order changed in treated hosts to PLs, GRs, PRs, SPs and OEs, i.e., GRs that were less prevalent in the haemolymph of control larvae increased significantly in PII‐treated hosts. In the latters, sharp rise in GRs levels followed parasitoid emergence. OEs cells were scarce in both treated and untreated hosts. No significant difference was observed between the overall means of PLs in both types of host larvae. But GRs‐PRs was markedly altered in treated larvae. 相似文献
33.
Serine protease inhibitors (PIs) have been described in many plant species and are universal throughout the plant kingdom, where trypsin inhibitors is the most common type. In the present study, trypsin and chymotrypsin inhibitory activity was detected in the seed flour extracts of 13 selected cultivars/accessions of cowpea. Two cowpea cultivars, Cream7 and Buff, were found to have higher trypsin and chymotrypsin inhibitory potential compared to other tested cultivars for which they have been selected for further purification studies using ammonium sulfate fractionation and DEAE‐Sephadex A‐25 column. Cream7‐purified proteins showed two bands on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS‐PAGE) corresponding to molecular mass of 17.10 and 14.90 kDa, while the purified protein from Buff cultivar showed a single band corresponding mass of 16.50 kDa. The purified inhibitors were stable at temperature below 60°C and were active at wide range of pH from 2 to 12. The kinetic analysis revealed noncompetitive type of inhibition for both inhibitors against both enzymes. The inhibitor constant (Ki) values suggested high affinity between inhibitors and enzymes. Purified inhibitors were found to have deep and negative effects on the mean larval weight, larval mortality, pupation, and mean pupal weight of Spodoptera littoralis, where Buff PI was more effective than Cream7 PI. It may be concluded that cowpea PI gene(s) could be potential insect control protein for future studies in developing insect‐resistant transgenic plants. 相似文献
34.
Sophie Borgella Nadine Fievet Bich-Tram Huynh Samad Ibitokou Gbetognon Hounguevou Jacqueline Affedjou Jean-Claude Sagbo Parfait Houngbegnon Blaise Guezo-Mévo Achille Massougbodji Adrian J. F. Luty Michel Cot Philippe Deloron 《PloS one》2013,8(11)
Background
Infants of mothers with placental Plasmodium falciparum infections at delivery are themselves more susceptible to malaria attacks or to infection in early life.Methodology/ Principal Findings
To assess the impact of either the timing or the number of pregnancy-associated malaria (PAM) infections on the incidence of parasitemia or malaria attacks in infancy, we followed 218 mothers through pregnancy (monthly visits) up to delivery and their infants from birth to 12 months of age (fortnightly visits), collecting detailed clinical and parasitological data. After adjustment on location, mother’s age, birth season, bed net use, and placental malaria, infants born to a mother with PAM during the third trimester of pregnancy had a significantly increased risk of infection (OR [95% CI]: 4.2 [1.6; 10.5], p = 0.003) or of malaria attack (4.6 [1.7; 12.5], p = 0.003). PAM during the first and second trimesters had no such impact. Similarly significant results were found for the effect of the overall number of PAM episodes on the time to first parasitemia and first malaria attack (HR [95% CI]: 2.95 [1.58; 5.50], p = 0.001 and 3.19 [1.59; 6.38], p = 0.001) respectively.Conclusions/ Significance
This study highlights the importance of protecting newborns by preventing repeated episodes of PAM in their mothers. 相似文献35.
Ahmady Y. Ahmed Amany M. Gad Ola M. Abd El‐Raouf 《Journal of biochemical and molecular toxicology》2017,31(10)
Exposure to drugs often results in toxicity in the kidney which represents the major control system maintaining homeostasis of the body and thus is especially susceptible to xenobiotics. Nephrotoxicity is a life‐threatening side‐effect of nonsteroidal anti‐inflammatory drugs (NSAIDs). Diclofenac is one of the most frequently prescribed NSAIDs and have been reported to cause multiple organs damage. Curcumin (CUR) exhibits nephroprotective properties. Therefore, rats were divided into four groups; rats of groups 3 and 4 received diclofenac (100 mg/kg, i.m.), whereas rats of groups 2 and 4 received CUR (100 mg/kg, p.o.) for 3 days. Diclofenac revealed a significant increase in urea and creatinine levels and malondialdehyde concentration and marked reduction in catalase activity and reduced glutathione concentration. Histopathologically, diclofenac produced fatty changes and eosinophilic casts were detected in the renal tubules, those were attenuated by administration of CUR prior diclofenac. 相似文献
36.
Kanani MR Rahiminejad MR Sonboli A Mozaffarian V Kazempour Osaloo S Nejad Ebrahimi S 《化学与生物多样性》2011,8(3):503-517
To evaluate the chemotaxonomic significance of the essential oils of 23 populations of 18 Iranian Ferula species, the chemical composition of the oils was investigated by GC/FID and GC/MS. Altogether, 84 constituents, representing 81.3-99.7% of the total composition of the oils, have been identified. The composition of six species of the genus, i.e., F. oopoda, F. foetida, F. behboudiana, F. diversivittata, F. galbaniflua, and F. hezarlalehzarica, has been reported for the first time. The main constituents identified were α-terpinyl acetate (73.3%), 2,3,4-trimethylthiophene (2; 49.0%), sabinene (75.3%), verbenone (5; 69.4%), β-pinene (59.0-66.3%), and (Z)-β-ocimene (41.7%). Cluster analysis (CA) of the percentage content of the essential oil components of the Ferula species resulted in the characterization of four groups, i.e., taxa containing either i) monoterpene hydrocarbons, ii) oxygenated monoterpenes, iii) organosulfur compounds, or iv) monoterpene, sesquiterpene, and aliphatic hydrocarbons as the principal classes of compounds. Based on the results obtained, the chemical independence of F. hirtella from F. szowitsiana and of F. galbaniflua from F. gummosa at the specific level was concluded and their positions as distinct species were confirmed. The chemotaxonomic relationships among the representatives of the genus Ferula have been discussed in detail. 相似文献
37.
Haider Karar Muhammad Amjad Bashir Reem Atalla Alajmi Dina M. Metwally Muneeba Haider Najeeba Haider Samad Raza Ali Bakhsh Rania Haddadi 《Saudi Journal of Biological Sciences》2021,28(7):3936-3942
In 2004–05, during the December to February about 141 mango farmers were interviewed during peak activity of mango mealy bug in southern Punjab, Pakistan. The objective was to know the farmers’ knowledge, perceptions and practices in the management of mango mealy bug. Most of the farmers (94.33%) reported that Chaunsa variety (king of all mango varieties) was susceptible to mango and irrigation water was the major source of flare up of this pest. Basudin and Supracide were the most commonly used insecticides as 72.92 and 51.77 percent farmers gave positive response and grease bands were applied for the control of mango mealy bug by the majority of the respondents. Hundred percent yield losses was told by 22.7 percent respondents whereas 75 percent, 50 percent and 25 percent losses were reported by 39.7, 31.9 and 14.2 insecticidal spray did not show satisfaction to the respondents for the control of fertilized females of mango mealy bug coming down from the trees. Lack of knowledge about the pest, lack of money, adulterated and shortage of pesticides, lack of unity amongst farmers Further the growers’ views were tested in the field for confirmation and small land holdings were the main constraints for the control of mango mealy bug. 相似文献
38.
39.
A new species of corophiid Amphipoda, Cheiriphotis trifurcata, collected from the seagrass bed of the Lower Gulf of Thailand, is described. Cheiriphotis trifurcata is characterized by its trifurcated tip of the modified setae on the outer ramus in male pleopod 3. In this paper, the new species is fully described and compared with related species and a complete key of the 16 valid species in the genus Cheiriphotis is given. 相似文献
40.
Fisher N Abd Majid R Antoine T Al-Helal M Warman AJ Johnson DJ Lawrenson AS Ranson H O'Neill PM Ward SA Biagini GA 《The Journal of biological chemistry》2012,287(13):9731-9741
Atovaquone is an anti-malarial drug used in combination with proguanil (e.g. Malarone(TM)) for the curative and prophylactic treatment of malaria. Atovaquone, a 2-hydroxynaphthoquinone, is a competitive inhibitor of the quinol oxidation (Q(o)) site of the mitochondrial cytochrome bc(1) complex. Inhibition of this enzyme results in the collapse of the mitochondrial membrane potential, disruption of pyrimidine biosynthesis, and subsequent parasite death. Resistance to atovaquone in the field is associated with point mutations in the Q(o) pocket of cytochrome b, most notably near the conserved Pro(260)-Glu(261)-Trp(262)-Tyr(263) (PEWY) region in the ef loop). The effect of this mutation has been extensively studied in model organisms but hitherto not in the parasite itself. Here, we have performed a molecular and biochemical characterization of an atovaquone-resistant field isolate, TM902CB. Molecular analysis of this strain reveals the presence of the Y268S mutation in cytochrome b. The Y268S mutation is shown to confer a 270-fold shift of the inhibitory constant (K(i)) for atovaquone with a concomitant reduction in the V(max) of the bc(1) complex of ~40% and a 3-fold increase in the observed K(m) for decylubiquinol. Western blotting analyses reveal a reduced iron-sulfur protein content in Y268S bc(1) suggestive of a weakened interaction between this subunit and cytochrome b. Gene expression analysis of the TM902CB strain reveals higher levels of expression, compared with the 3D7 (atovaquone-sensitive) control strain in bc(1) and cytochrome c oxidase genes. It is hypothesized that the observed differential expression of these and other key genes offsets the fitness cost resulting from reduced bc(1) activity. 相似文献