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71.
Mohamad Nafis Abdul Razak Mohamad Faizal Ibrahim Phang Lai Yee Mohd Ali Hassan Suraini Abd-Aziz 《Biotechnology and Bioprocess Engineering》2012,17(3):547-555
The abundance of oil palm decanter cake (OPDC) is a problem in oil palm mills. However, this lignocellulosic biomass can be utilized for cellulase and polyoses production. The effectiveness of chemical and physical pretreatment in reducing the lignin content was studied by saccharification using a Celluclast 1.5 L and scanning electron microscope. Physicochemical pretreatment of OPDC with 1% (w/v) NaOH and autoclaving at 121°C for 20 min increased potential polyoses produced to 52.5% and removed 28.7% of the lignin content. The optimized conditions for cellulase production by a locally isolated fungus were a time of 120 h, a substrate of untreated OPDC, a spore concentration of 1 × 107 spore/mL, a temperature of 30°C, and a pH between 7.0 and 7.5. Trichoderma asperellum UPM1 produced carboxymethylcellulase (CMCase), ??-glucosidase and filter paper activity (FPase) in the following concentrations: 17.35, 0.53, and 0.28 U/mL, respectively. Aspergillus fumigatus UPM2 produced the CMCase, ??-glucosidase and FPase in the following amounts: 10.93, 0.76, and 0.24 U/mL. The cellulases from T. asperellum UPM1 produced 2.33 g/L of polyoses and the cellulases from A. fumigatus UPM2 produced 4.37 g/L of polyoses. 相似文献
72.
Helen E. Fox Jill L. Harris Emily S. Darling Gabby N. Ahmadia Estradivari Tries B. Razak 《Restoration Ecology》2019,27(4):862-869
Calls for coral reef restoration are increasing amidst continued declines, yet we know little about long‐term outcomes and conditions that lead to successful coral recovery. Here, we report on one of the longest monitoring studies following 16 years of large‐scale, “low‐tech” experimental reef rehabilitation on rubble fields created by chronic blast fishing in Komodo National Park, Indonesia. After blast fishing had stopped, in the absence of rehabilitation, hard coral cover in rubble fields remained about 3% from 1999 to 2016, but on rehabilitation treatments, cover increased from 0% in 2002 to 44.5% (±21.9% SD) in 2016. Coral cover varied among sites and treatments (ranging from <5 to >80% in 2016) in patterns that may reflect current strength and turbidity. Our results demonstrate that low‐tech substrate stabilization can facilitate natural coral recruitment and growth. We conclude that relatively low‐cost methods can deliver sustained rehabilitation of hard coral cover and that long‐term monitoring should be incorporated more widely in restoration activities to inform return on investment. 相似文献
73.
Mohd Ridzuan Mohd Abd Razak Umi Rubiah Sastu Nor Azrina Norahmad Abass Abdul-Karim Amirrudin Muhammad Prem Kumar Muniandy Jenarun Jelip Christina Rundi Mallika Imwong Rose Nani Mudin Noor Rain Abdullah 《PloS one》2016,11(3)
Malaysia has a national goal to eliminate malaria by 2020. Understanding the genetic diversity of malaria parasites in residual transmission foci can provide invaluable information which may inform the intervention strategies used to reach elimination targets. This study was conducted to determine the genetic diversity level of P. falciparum isolates in malaria residual foci areas of Sabah. Malaria active case detection was conducted in Kalabakan and Kota Marudu. All individuals in the study sites were screened for malaria infection by rapid diagnostic test. Blood from P. falciparum-infected individuals were collected on filter paper prior to DNA extraction. Genotyping was performed using merozoite surface protein-1 (MSP-1), merozoite surface protein-2 (MSP-2), glutamate rich protein (GLURP) and 10 neutral microsatellite loci markers. The size of alleles, multiplicity of infection (MOI), mean number of alleles (Na), expected heterozygosity (He), linkage disequilibrium (LD) and genetic differentiation (FST) were determined. In Kalabakan, the MSP-1 and MSP-2 alleles were predominantly K1 and FC27 family types, respectively. The GLURP genotype VI (751–800 bp) was predominant. The MOI for MSP-1 and MSP-2 were 1.65 and 1.20, respectively. The Na per microsatellite locus was 1.70. The He values for MSP-1, MSP-2, GLURP and neutral microsatellites were 0.17, 0.37, 0.70 and 0.33, respectively. In Kota Marudu, the MSP-1 and MSP-2 alleles were predominantly MAD20 and 3D7 family types, respectively. The GLURP genotype IV (651–700 bp) was predominant. The MOI for both MSP-1 and MSP-2 was 1.05. The Na per microsatellite locus was 3.60. The He values for MSP-1, MSP-2, GLURP and neutral microsatellites were 0.24, 0.25, 0.69 and 0.30, respectively. A significant LD was observed in Kalabakan (0.495, p<0.01) and Kota Marudu P. falciparum populations (0.601, p<0.01). High genetic differentiation between Kalabakan and Kota Marudu P. falciparum populations was observed (FST = 0.532). The genetic data from the present study highlighted the limited diversity and contrasting genetic pattern of P. falciparum populations in the malaria declining areas of Sabah. 相似文献
74.
75.
Mo K Razak Z Rao P Yu Z Adachi H Katsuno M Sobue G Lieberman AP Westwood JT Monks DA 《PloS one》2010,5(9):e12922
Background
Emerging evidence implicates altered gene expression within skeletal muscle in the pathogenesis of Kennedy disease/spinal bulbar muscular atrophy (KD/SBMA). We therefore broadly characterized gene expression in skeletal muscle of three independently generated mouse models of this disease. The mouse models included a polyglutamine expanded (polyQ) AR knock-in model (AR113Q), a polyQ AR transgenic model (AR97Q), and a transgenic mouse that overexpresses wild type AR solely in skeletal muscle (HSA-AR). HSA-AR mice were included because they substantially reproduce the KD/SBMA phenotype despite the absence of polyQ AR.Methodology/Principal Findings
We performed microarray analysis of lower hindlimb muscles taken from these three models relative to wild type controls using high density oligonucleotide arrays. All microarray comparisons were made with at least 3 animals in each condition, and only those genes having at least 2-fold difference and whose coefficient of variance was less than 100% were considered to be differentially expressed. When considered globally, there was a similar overlap in gene changes between the 3 models: 19% between HSA-AR and AR97Q, 21% between AR97Q and AR113Q, and 17% between HSA-AR and AR113Q, with 8% shared by all models. Several patterns of gene expression relevant to the disease process were observed. Notably, patterns of gene expression typical of loss of AR function were observed in all three models, as were alterations in genes involved in cell adhesion, energy balance, muscle atrophy and myogenesis. We additionally measured changes similar to those observed in skeletal muscle of a mouse model of Huntington''s Disease, and to those common to muscle atrophy from diverse causes.Conclusions/Significance
By comparing patterns of gene expression in three independent models of KD/SBMA, we have been able to identify candidate genes that might mediate the core myogenic features of KD/SBMA. 相似文献76.
The effects of phenolic monomers (i.e. rho-coumaric acid, ferulic acid, rho-hydroxybenzaldehyde and vanillin) on the enzymes and fermentation activities of Neocallimastix frontalis B9 grown in ball-milled filter paper and guinea grass media were studied. The enzymes studied were carboxymethylcellulase (CMCase), filterpaperase (FPase), xylanase and beta-glucosidase. At 96 h of incubation, N. frontalis grown in ball-milled filter paper medium produced comparable xylanase and CMCase activities (0.41, 0.5 micromol/min/mg protein) while in guinea grass medium, N. frontalis produced higher xylanase activity than that of CMCase activity (2.35, 0.05 micromol/min/mg protein). The other enzymes activities were low. When N. frontalis was grown in ball-milled filter paper medium, only acetic acid was produced. However, when grown in guinea grass medium, the major end-product was acetate, but propionic, butyric and isovaleric were also produced in lesser amount. Vanillin showed the least inhibitory effects to enzyme activities of N. frontalis B9 grown in both ball-milled filter paper and guinea grass media. For total volatile fatty acid production, all phenolic monomers showed inhibitory effects, but rho-coumaric and ferulic acids were the stronger inhibitors than rho-hydroxybenzaldehyde and vanillin. 相似文献
77.
C. N. A. Razak W. F. Wang S. H. S. A. Rahman M. Basri A. B. Salleh 《Engineering in Life Science》1999,19(3):213-223
The Acinetobacter sp. E11, isolated from Port Dickson Beach, Malaysia, was able to grow in media containing crude oil as the sole carbon and energy source. Substrate specificity studies showed that the bacterium exhibited substrate preference as growth was observed only in media containing aliphatic hydrocarbons, while aromatic and cyclic hydrocarbons inhibited growth. With the aliphatic hydrocarbons, growth was seen only in the long-chain alkanes tested (pentadecane, dodecane and hexadecane). No growth was recorded in the short-chain alkanes (pentane, hexane and heptane) tested. With complex hydrocarbons, only crude oil and 4T SHELL engine oil supported growth. No growth was observed in kerosene and PETRONAS gasoline. The isolate could grow in up to 10% and 20% [v/v] of the crude oil and alkanes tested, respectively. Among the long-chain alkanes tested, hexadecane was the most preferred, followed by pentadecane and dodecane. Nitrogen and phosphorous supplements were essential for growth and the best growth was achieved with 3% nitrogen/phosphorous additions. Microscopic observation revealed that the bacterium adhered to the hexadecane and crude oil droplets. GC analysis showed that the bacterium was able to degrade more than 60% of the hydrocarbons in the crude oil in 15 days at 37°C compared to the uninoculated media. 相似文献
78.
Azraul Mumtazah Razak Shy Cian Khor Faizul Jaafar Norwahidah Abdul Karim Suzana Makpol 《Genes & nutrition》2018,13(1):31
Background
Several muscle-specific microRNAs (myomiRs) are differentially expressed during cellular senescence. However, the role of dietary compounds on myomiRs remains elusive. This study aimed to elucidate the modulatory role of tocotrienol-rich fraction (TRF) on myomiRs and myogenic genes during differentiation of human myoblasts. Young and senescent human skeletal muscle myoblasts (HSMM) were treated with 50 μg/mL TRF for 24 h before and after inducing differentiation.Results
The fusion index and myotube surface area were higher (p?<?0.05) on days 3 and 5 than that on day 1 of differentiation. Ageing reduced the differentiation rate, as observed by a decrease in both fusion index and myotube surface area in senescent cells (p?<?0.05). Treatment with TRF significantly increased differentiation at days 1, 3 and 5 of young and senescent myoblasts. In senescent myoblasts, TRF increased the expression of miR-206 and miR-486 and decreased PTEN and PAX7 expression. However, the expression of IGF1R was upregulated during early differentiation and decreased at late differentiation when treated with TRF. In young myoblasts, TRF promoted differentiation by modulating the expression of miR-206, which resulted in the reduction of PAX7 expression and upregulation of IGF1R.Conclusion
TRF can potentially promote myoblast differentiation by modulating the expression of myomiRs, which regulate the expression of myogenic genes.79.
Bahrin EK Ibrahim MF Abd Razak MN Abd-Aziz S Shah UK Alitheen N Salleh MM 《Preparative biochemistry & biotechnology》2012,42(2):155-170
The response surface method was applied in this study to improve cellulase production from oil palm empty fruit bunch (OPEFB) by Botryosphaeria rhodina. An experimental design based on a two-level factorial was employed to screen the significant environmental factors for cellulase production. The locally isolated fungus Botryosphaeria rhodina was cultivated on OPEFB under solid-state fermentation (SSF). From the analysis of variance (ANOVA), the initial moisture content, amount of substrate, and initial pH of nutrient supplied in the SSF system significantly influenced cellulase production. Then the optimization of the variables was done using the response surface method according to central composite design (CCD). Botryosphaeria rhodina exhibited its best performance with a high predicted value of FPase enzyme production (17.95 U/g) when the initial moisture content was at 24.32%, initial pH of nutrient was 5.96, and 3.98 g of substrate was present. The statistical optimization from actual experiment resulted in a significant increment of FPase production from 3.26 to 17.91 U/g (5.49-fold). High cellulase production at low moisture content is a very rare condition for fungi cultured in solid-state fermentation. 相似文献
80.
Mohamed Boukhary Osman Abdelghany Yasmine Hussein-Kamel Salah Bahr Abdul Razak Alsayigh Mousheera Abdelraouf 《Historical Biology》2013,25(4):348-366
An early Oligocene (Rupelian) diagnostic larger foraminiferal assemblage is described and illustrated from marls and limestones of the Asmari Formation, at Jabals Hafit and Malaqet in the UAE. An equivalent assemblage is identified in the mudstones of the Tahwah Formation, Wadi Suq, Oman. Although Nummulites intermedius (D'Archiac 1846) and N. fichteli are fully synonymous (e.g. Roveda 1970; Schaub 1981; Sirel 2003), in this study both species are biometrically differentiated, distinct and both names are valid. N. fichteli Michelotti 1841, N. intermedius (D'Archiac 1846) and N. emiratus n. sp., which are index for the early Oligocene (Rupelian), and they are replacing each others competitively and environmentally. The presence of Blondeauina bouillei n.gen., N. emiratus n.sp., N. intermedius, N. fichteli, Planoperculina complanata (Defrance 1822) and Austrotrillina asmariensis Adams 1968 ascribed the section of the Asmari Formation to the early Oligocene (Rupelian). The studied marls and limestones were deposited in outer and inner shelf environments, respectively. The Asmari Formation in the area studied consists mainly of marl in its lower portion and reefal limestone in its upper part, indicating a major marine regression. The Tahwah Formation in Oman is composed of bioturbated silty and muddy marls and is a facies equivalent to the Asmari Formation marls. The Asmari Formation facies change probably relates to a mid-Oligocene fall in global sea level. In this study, the Dabaa Formation, a subsurface unit of late Eocene–Oligocene marine shales in the north Western Desert of Egypt, was chosen to correlate with the Oligocene of Emirates and Oman. The Dabaa Formation comprises Spiroclypeus ornatus (Henson 1937) and Eulepidina dilatata (Michelotti 1861). The environment of deposition was inner shelf to littoral, which become estuarine towards the top in many areas. This Oligocene Dabaa sequence is correlatable with Wadi El Arish sequence recently discovered by Kuss and Boukhary (2008) from Risan Aneiza, Northern Sinai, Egypt. 相似文献