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201.
The Alitropus typus infestation has a serious influence on fish farming in Pakistan. The present study focuses on the external morphology and control of highly infested ectoparasitic isopod Alitropus typus. Sixteen morphological parameters of the whole body were measured and statistically analyzed for mean, standard error and coefficient of variation by using the student t test. Non‐significant variations were observed in the size of pereopods which depict the significance of swimming and attached to its host. For biological control, different concentrations (1000, 5000 and 10 000 ppm) of a leaf extract of four plants (i.e. Euphorbia helioscopia, Ajuga bracteosa, Cannabis sativa and Callistemon citrinus) were tested against A. typus, and the mortality rates were recorded after 12, 24 and 36 h. One way Anova and Tukey tests were used to analyze the results. The recorded percentage mortality was in the order of E. helioscopia > A. bracteosa > C. sativa, whereas C. citrinus did not showed any toxicity. Concentrations of biochemical components like carbohydrates (mg/g), proteins (mg/g), and lipids (mg/dL) of treated isopods were estimated by the phenol‐sulfuric acid process, Lowry's method and biochemistry analyzer, respectively. The protein contents of the insects tested had decreased markedly as compared to control rates, and this might be due to insecticidal stress caused by the extracts. In another biocontrol experiment, crabs were introduced along with isopods into an aquarium. It was then noted that one crab consumes an average of seven isopods/week and can act as a scavenger for dead organisms. 相似文献
202.
Sulaiman Al‐Zuhair Salman Ashraf Soleiman Hisaindee Naeema Al Darmaki Sinan Battah Dimitri Svistunenko Brandon Reeder Glyn Stanway Afeefa Chaudhary 《Engineering in Life Science》2017,17(2):175-185
Crude proteins and pigments were extracted from different microalgae strains, both marine and freshwater. The effectiveness of enzymatic pre‐treatment prior to protein extraction was evaluated and compared to conventional techniques, including ultrasonication and high‐pressure water extraction. Enzymatic pre‐treatment was chosen as it could be carried out at mild shear conditions and does not subject the proteins to high temperatures, as with the ultrasonication approach. Using enzymatic pre‐treatment, the extracted proteins yields of all tested microalgae strains were approximately 0.7 mg per mg of dry cell weight. These values were comparable to those achieved using a commercial lytic kit. Ultrasonication was not very effective for proteins extraction from Chlorella sp., and the extracted proteins yields did not exceed 0.4 mg per mg of dry cell weight. For other strains, similar yields were achieved by both treatment methods. The time‐course effect of enzymatic incubation on the proteins extraction efficiency was more evident using laccase compared to lysozyme, which suggested that the former enzyme has a slower rate of cell disruption. The crude extracted proteins were fractionated using an ion exchange resin and were analyzed by the electrophoresis technique. They were further tested for their antioxidant activity, the highest of which was about 60% from Nannochloropsis sp. The total phenolic contents in the selected strains were also determined, with Chlorella sp. showing the highest content reaching 17 mg/g. Lysozyme was also found to enhance the extraction of pigments, with Chlorella sp. showing the highest pigments contents of 16.02, 4.59 and 5.22 mg/g of chlorophyll a, chlorophyll b and total carotenoids, respectively. 相似文献
203.
En route to economical eco‐friendly solvent system in enhancing sustainable recovery of poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate) copolymer
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Nik Murniati Nik Man Irdahayu Kannusamy Shantini Kai‐Hee Huong Sevakumaran Vigneswari Nursolehah Abdul Aziz Mohd. Noor Mohd. Azizan Al‐Ashraf Abdullah Amirul 《Engineering in Life Science》2017,17(9):1050-1059
Separation of poly(3‐hydroxybutyrate‐co‐4‐hydroxybutyrate) [P(3HB‐co‐4HB)] from bacterial cell matter is a critical step in the downstream process with respect to material quality and eco‐balance as P(3HB‐co‐4HB) is widely used for biomedical applications. Therefore, an efficient and eco‐based extraction of P(3HB‐co‐4HB) using a combination of NaOH and Lysol in digesting the non‐polymeric cell material (NPCM) digestion is developed. The NaOH and Lysol show synergistic influence on the copolymer extraction at a high purity and recovery of 97 and 98 wt% respectively. The optimized cell digestion method was found applicable to a vast batch of cells containing copolymers from various 4HB monomer compositions. At the largest extraction volume of 100 L, P(3HB‐co‐4HB) with a purity of 89 wt% was extracted with a maximum recovery of 90 wt%. The method developed has also eliminated the cell pretreatment step. The extraction method developed in this research has not only produced an economic and efficient copolymer recovery but has also retained the copolymer quality, in term of its molecular weight and thermal properties. It demonstrates a practical and promising downstream processing method in recovering the copolymer effectively from the bacterial biomass. 相似文献
204.
We developed a conditional overexpression/suppression genetic strategy in Candida albicans to enable simultaneous testing of gain or loss of function in order to identify new virulence factors. The strategy involved insertion of a strong, tetracycline-regulated promoter in front of the gene of interest. To validate the strategy, a library of genes encoding glycosylphosphatidylinositol (GPI)-anchored surface proteins was screened for virulence phenotypes in vitro. During the screening, overexpression of IFF4 was found to increase the adherence of C. albicans to plastic and to human epithelial cells, but not endothelial cells. Consistent with the in vitro results, IFF4 overexpression modestly increased the tissue fungal burden during murine vaginal candidiasis. In addition to the in vitro screening tests, IFF4 overexpression was found to increase C. albicans susceptibility to neutrophil-mediated killing. Furthermore, IFF4 overexpression decreased the severity of hematogenously disseminated candidiasis in normal mice, but not in neutropenic mice, again consistent with the in vitro phenotype. Overexpression of 12 other GPI proteins did not affect normal GPI protein cell surface accumulation, demonstrating that the overexpression strategy did not affect the cell capacity for making such proteins. These data indicate that the same gene can increase or decrease candidal virulence in distinct models of infection, emphasizing the importance of studying virulence genes in different anatomical contexts. Finally, these data validate the use of a conditional overexpression/suppression genetic strategy to identify candidal virulence factors. 相似文献
205.
Ghanem A Aboul-Enein MN El-Azzouny A El-Behairy MF Al-Humaidi E Alaidan AA Amin K Al-Ahdal MN 《Chirality》2008,20(8):871-877
The first straightforward lipase-catalyzed enantioselective access to enantiomerically enriched tiaprofenic acid as a versatile method in chiral separation of racemates is demonstrated. The latter was directly monitored by enantioselective HPLC using a 3,5-dimethylphenylcarbamate derivative of cellulose-based chiral stationary phase namely Chiralpak IB (the immobilized version of Chiralcel OD). Non-standard HPLC organic solvents were used as diluent to dissolve the "difficult to dissolve" enzyme substrate (the acid) and as eluent for the simultaneous enantioselective HPLC baseline separation of both substrate and product in one run without any further derivatization. The existence of a non-standard HPLC organic solvent (e.g., methyl tert-butyl ether) in the mobile phase composition is mandatory to accomplish the simultaneous enantioselective HPLC baseline separation of both substrate and product. 相似文献
206.
Amjad I. A. Hussein Ashraf M. Ahmed Maiko Sato Tadashi Shimamoto 《Microbiology and immunology》2009,53(11):595-602
Sixty Gram-negative bacterial isolates were collected from Palestinian hospitals in 2006. Thirty-two (53.3%) isolates showed multidrug resistance phenotypes. PCR and DNA sequencing were used to characterize integrons and antimicrobial resistance genes. PCR screening showed that 19 (31.7%) and five (8.3%) isolates were positive for class 1 and class 2 integrons, respectively. DNA-sequencing results for the captured antimicrobial resistance gene cassettes within class 1 integrons identified the following genes: dihydrofolate reductases, dfrA1 , dfrA5 , dfrA7 , dfrA12, dfrA17 and dfrA25 ; aminoglycoside adenyltransferases, aadA1, aadA2 , aadA5, aadA12 and aadB ; aminoglycoside acetyltransferase, aac(6')-Ib ; and chloramphenicol resistance gene, cmlA1 . ESBL were identified in 25 (41.7%) isolates. The identified ESBL were bla CTX-M-15 , bla CTX-M-56 , bla OXA-1 , bla SHV-1 , bla SHV-12 , bla SHV-32 and bla TEM-1 genes. Moreover, we characterized the plasmid-mediated quinolone resistance genes, aac(6')-Ib-cr and qnrB2 , which were detected in seven (11.7%) and two (3.3%) isolates, respectively. In this study various types of antibiotic resistance genes have been identified in Gram-negative bacteria from Palestinian hospitals, many of which are reported in the Middle East area for the first time. 相似文献
207.
Mohamed Ashraf Ali Jeyabalan Govinda Samy Elumalai Manogaran Velmurugan Sellappan Mohamed Zaheen Hasan Mohamed Jawed Ahsan Suresh Pandian Mohammad ShaharYar 《Bioorganic & medicinal chemistry letters》2009,19(24):7000-7002
In present investigation, a series of substituted phenyl-5,6-dimethoxy-1-oxo-2,5-dihydro-1H-2-indenylmethanone analogues were synthesized and were evaluated for antimycobacterial activity against Mycobacterium tuberculosis H37Rv and INH resistant M. tuberculosis. All the newly synthesized compounds were showing moderate to high inhibitory activities. The compound 5,6-dimethoxy-1-oxo-2,5-dihydro-1H-2-indenyl-4-fluorophenylmethanone (5g) was found to be the most promising compounds active against M. tuberculosis H37Rv and isoniazid (INH) resistant M. tuberculosis with Minimum inhibitory concentration 0.10 and 0.10 μM. 相似文献
208.
Mohamed Ashraf Ali Mohammad Shahar Yar Mohamed Zaheen Hasan Mohamed Jawed Ahsan Suresh Pandian 《Bioorganic & medicinal chemistry letters》2009,19(17):5075-5077
In present investigation, a series of substituted phenyl-5,6-dimethoxy-1-oxo-2,3-dihydro-1H-2-indenylmethanone analogues were synthesized and were tested for their potential for treating AD disease. All the newly synthesized compounds were showing moderate to high AChE inhibitory activities, with compound 5,6-dimethoxy-1-oxo-2,3-dihydro-1H-2-indenyl-3,4,5-trimethoxyphenylmethanone (5f) produced significant activities with 2.7 ± 0.01 μmol/L. 相似文献
209.
Arvind Kumar Gupta Ashraf Yusuf Rangrez Pankaj Verma Anil Chatterji Yogesh S. Shouche 《Indian journal of microbiology》2009,49(2):169-187
Microbial communities in coastal subsurface sediments play an important role in biogeochemical cycles. In this study microbial
communities in tidal subsurface sediments of Balramgari in the state of Orissa, India were investigated using a culture independent
approach. Two 16S rDNA cloned libraries were prepared from the closely located (100 m along the coast) subsurface sediment
samples. Library I sediment samples had higher organic carbon content but lower sand percentage in comparison to Library II.
A total of 310 clone sequences were used for DOTUR analysis which revealed 51 unique phylotypes or operational taxonomic units
(OTUs) for both libraries. The OTUs were affiliated with 13 major lineages of domain bacteria including Proteobacteria (α, β, δ and λ), Acidobacteria, Actinobacteria, Cyanobacteria, Chloroflexi, Firmicutes, Verrucomicrobia, Bacteroidetes, Gemmatimonadetes and TM7. We encountered few pathogenic bacteria such as Aeromonas hydrophila and Ochrobactrum intermedium, in sediment from Library I. ∫-LIBSHUFF comparison depicts that the two libraries were significantly different communities.
Most of the OTUs from both libraries possessed ≥85% to <97% similarity to RDP database sequences depicting the putative presence
of new species, genera and phylum. This work revealed the complex and unique bacterial diversity from coastal habitat of Balramgari
and shows that, in coastal habitat a variability of physical and chemical parameter has a prominent impact on the microbial
community structure. 相似文献
210.
Muhammad Sajid Aqeel Ahmad Qasim Ali Muhammad Ashraf Muhammad Zulqarnain Haider Qaswar Abbas 《Environmental and Experimental Botany》2009,66(3):409-417
A hydroponic experiment was conducted to assess the possible involvement of polyamines (PAs), abscisic acid (ABA) and anti-oxidative enzymes such as superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) in adaptation of six populations of Panicum antidotale Retz. to selection pressure (soil salinity) of a wide range of habitats. Plants of six populations were collected from six different habitats with ECe ranging from 3.39 to 19.23 dS m−1 and pH from 7.65 to 5.86. Young tillers from 6-month-old plants were transplanted in plastic containers each containing 10 l of half strength Hoagland's nutrient solution alone or with 150 mol m−3 NaCl. After 42 days growth, contents of polyamines (Put, Spd and Spm) and ABA, and the activities of anti-oxidative enzymes (SOD, POD and CAT) of all populations generally increased under salt stress. The populations collected from highly saline habitats showed a greater accumulation of polyamines and ABA and the activities of anti-oxidative enzymes as compared to those from mild or non-saline habitats. Moreover, Spm/Spd and Put/(Spd + Spm) ratios generally increased under salt stress. However, the populations from highly saline environments had significantly higher Spm/Spd and Put/(Spd + Spm) ratios as compared to those from mild or non-saline environments. Similarly, the populations adapted to high salinity accumulated less Na+ and Cl− in culm and leaves, and showed less decrease in leaf K+ and Ca2+ under salinity stress. Higher activities of anti-oxidative enzymes and accumulation of polyamines and ABA, and increased Spm/Spd and Put/(Spm + Spd) ratios were found to be highly correlated with the degree of adaptability of Panicum to saline environment. 相似文献