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Detection of virulent Newcastle disease virus using a phage-capturing dot blot assay

Lee TC, Yusoff K, Nathan S, Tan WS

J Virol Methods, 2006 Sep;136(1-2):224-9.
PMID: 16797732

Newcastle disease virus (NDV) strains can be classified as virulent or avirulent based upon the severity of the disease. Differentiation of the virus into virulent and avirulent is necessary for effective control of the disease. Biopanning experiments were performed using a disulfide constrained phage displayed heptapeptide library against three pathotypes of NDV strains: velogenic (highly virulent), mesogenic (moderately virulent) and lentogenic (avirulent). A phage clone bearing the peptide sequence SWGEYDM capable of distinguishing virulent from avirulent NDV strains was isolated. This phage clone was employed as a diagnostic reagent in a dot blot assay and it successfully detected only virulent NDV strains.
Fulltext Repeated time-series cross-validation: A new method to improved COVID-19 forecast accuracy in Malaysia

Abdul Aziz A, Yusoff M, Yaacob WFW, Mustaffa Z

MethodsX, 2024 Dec;13:103013.
PMID: 39559463 DOI: 10.1016/j.mex.2024.103013

Forecasting COVID-19 cases is challenging, and inaccurate forecast values will lead to poor decision-making by the authorities. Conversely, accurate forecasts aid Malaysian government authorities and agencies (National Security Council, Ministry of Health, Ministry of Finance, Ministry of Education, and Ministry of International Trade and Industry) and financial institutions in formulating action plans, regulations, and legal acts to control COVID-19 spread in the country. Therefore, this study proposes Repeated Time-Series Cross-Validation, a new data-splitting strategy to identify the best forecasting model that is capable of producing the lowest error measures value and a high percentage of forecast accuracy for COVID-19 prediction in Malaysia. Some of the highlights of the proposed method are:•A total of 21 models, five data partitioning sets, and four error measures to improve the forecast accuracy of daily COVID-19 cases in Malaysia.•The best model selected produces the lowest error measure value for the Root Mean Squared Error (RMSE), Mean Absolute Error (MAE), Mean Absolute Percentage Error (MAPE), and Mean Absolute Scaled Error (MASE).•The average 8-day forecast accuracy is 90.2 %. The lowest and highest forecast accuracy was 83.7 % and 98.7 %.
Fulltext Feasibility Study of Using Hydrophobic Geopolymer-Based as Aggregate Substitution in Asphalt Mixture

Ago C, Li G, Wu J, Md Yusoff NI

Polymers (Basel), 2023 Jul 18;15(14).
PMID: 37514465 DOI: 10.3390/polym15143077

Hydrophobic aggregates have the great ability to prevent asphalt pavement roads from stripping-off of the asphalt in presence of water. In addition, they give the option to consume less asphalt and save cost. On the other hand, natural aggregates have been found to be non-renewable and rare. Geopolymer based artificial aggregates are great materials as they demonstrated to have exceptional features, such as high strength, superior durability, and greater resistance to fire exposure. In this study, a new hydrophobic geopolymer based aggregate has been produced with rice ash (RA) and fly ash as precursors as well as, Sodium Hydroxide (NaOH) and Sodium Silicate (Na2SiO3) as activators. The mechanical properties combined with the softening coefficient, surface properties of samples, contact angle and adhesion were characterized as well as microstructure X-ray diffraction (XRD) and Scanning electron microscopy (SEM) test. The results indicate that the activators Na2SiO3/NaOH at a mix ratio of 1 have a suitable effect on the pores and the compressive strength of the new artificial aggregate most particularly sodium hydroxide. Nonetheless, it has been found that coating the artificial aggregate with asphalt showed a great improvement of the hydrophobic nature of the produced artificial aggregate based geopolymer. Hence, indicates the possibility of using it as recycle aggregate pavement. From a microstructure point, the hydrophobic nature of the new alkali-activated artificial aggregate can be improved by increasing the quantity of mullite in the mix proportion design.
Fulltext Physico-chemical and Sensory Properties of Red Palm Oil-based Ice Cream Using Maltodextrin or Modified Starch as Stabilizers

Zaini NSM, Mansor N, Yusoff MM, Rahim MHA

J Oleo Sci, 2023 Aug 31;72(9):811-818.
PMID: 37574285 DOI: 10.5650/jos.ess23036

This study highlights the use of red palm oil (RPO) as an alternative to dairy fat in a hard ice cream sample in the presence of different stabilizers; maltodextrin (MALTOD) and modified starch (MSTARCH). No stabilizer was added in the control sample (CO), while the different ratios of RPO to each stabilizer were 4:1, 3:2, and 2:3, coded as MALTOD1, MALTOD2, MALTOD3 for maltodextrin, and MSTARCH1, MSTARCH2, and MSTARCH3 for modified starch, respectively. These samples were compared regarding overrun, physical, and sensory properties. For MALTOD, sample MALTOD3 had the highest overrun (49.31±13.78%), while MALTOD2 had the highest viscosity (7.90±0.03 Pa.s) and hardness (1.09±0.07 kg), and MALTOD1 had the lowest melting properties (61.10±0.20%). For MSTARCH, sample MSTARCH1 had the highest hardness (3.39±0.07 kg), MSTARCH2 had the highest overrun (67.64±2.27%), and MSTARCH3 had the highest viscosity (8.19±0.24 Pa.s) and the lowest melting properties (39.83±0.20%). Samples MALTOD3 and MSTARCH1 were selected for comparison with commercial samples in terms of sensory acceptance and preference. There was no significant difference (p > 0.05) between the sensory acceptability of MALTOD3 and MSTARCH1. However, both samples received a significantly lower (p < 0.05) ranking than the commercial samples in terms of appearance, texture, flavour, meltability, and overall acceptance. Future studies are recommended to improve the RPO-based ice cream sample, particularly in terms of its sensory properties.
Humic acid recovery from stabilized leachate: Characterization and interference with chemical oxygen demand-colour removal

Ahmed Z, Yusoff MS, Kamal NHM, Aziz HA

Waste Manag Res, 2023 Oct;41(10):1584-1593.
PMID: 37154233 DOI: 10.1177/0734242X231160687

Heterogeneous combinations of organic compounds (humic acid (HA) and fulvic acid) are the prime factor for the high concentration of colour and chemical oxygen demand (COD) in semi-aerobic stabilized landfill leachate. These organics are less biodegradable and cause a severe threat to environmental elements. Microfiltration and centrifugation processes were applied in this study to investigate the HA removal from stabilized leachate samples and its corresponding interference with COD and colour. The three-stage extraction process recovered a maximum of 1412 ± 2.5 mg/L (Pulau Burung landfill site (PBLS) leachate), 1510 ± 1.5 mg/L (Alor Pongsu landfill site (APLS leachate) at pH 1.5 and 1371 ± 2.5 mg/L (PBLS) and 1451 ± 1.5 mg/L (APLS) of HA (about 42% of the total COD concentration) at pH 2.5, which eventually indicates the process efficiency. Comparative characteristics analysis of recovered HA by scanning electron microscopy, energy-dispersive X-ray, X-ray photoelectron spectroscopy, and Fourier transform infrared significantly indicate the existence of identical elements in the recovered HA compared with the previous studies. The higher reduction (around 37%) in ultraviolet (UV) absorbance values (UV254 and UV280) in the final effluent indicates the elimination of aromaticity and conjugated double-bond compounds from leachate. Moreover, 36 and 39% COD and 39 and 44% colour removal exhibit substantial interference.
Fulltext Spatial prediction of soil erosion risk using knowledge-driven method in Malaysia's Steepland Agriculture Forested Valley

Nasir Ahmad NSB, Mustafa FB, Muhammad Yusoff SY

Environ Dev Sustain, 2023 Apr 21.
PMID: 37362990 DOI: 10.1007/s10668-023-03251-8

Soil is a fundamental resource with its value vital to the world's ecosystem. Due to the fact that soil is one of the bases of all terrestrial life, humans cannot survive without it. However, soil erosion has jeopardized soil sustainability and affected the environmental quality, leaving a bad impact if these issues were not tackled at an earlier phase. Many research has been done to predict soil erosion susceptibility areas using different methods. This research aims to classify the contributing factors of soil erosion according to the risk and generate a soil erosion risk prediction map in Cameron Highlands. Thus, this research focuses on a knowledge-driven method that uses Analytical Hierarchy Process (AHP) technique to achieve the objectives. This technique consists of weighing the factors adopted by comparing pairs of factors that control erosion in this area through experts' opinions. 15 factors have been chosen to build the prediction map. Result shows that rainfall erosivity is the main factor contributing to soil erosion in Cameron Highlands which is 0.110, followed by land use (0.095), slope steepness (0.089), soil texture (0.079), NDVI (0.079), TWI (0.072), slope length (0.065), slope aspect (0.064), slope altitude (0.062), SPI (0.061), lithology (0.060), slope curvature (0.054), drainage density (0.049), distance to road (0.029) and distance to stream (0.025). The west part of the study area was exposed to a high risk of soil erosion. This research will give the decision-makers, policymakers and planners insight into minimizing the soil erosion problem and suggest better precautions and solutions to overcome this severe environmental problem in the more advanced phase.
Fulltext Effects of delayed metamorphosis on larval survival, metamorphosis, and juvenile performance of four closely related species of tropical sea urchins (genus Echinometra)

Rahman MA, Yusoff FM, Arshad A, Uehara T

ScientificWorldJournal, 2014;2014:918028.
PMID: 24624048 DOI: 10.1155/2014/918028

We report here, the effects of extended competency on larval survival, metamorphosis, and postlarval juvenile growth of four closely related species of tropical sea urchins, Echinometra sp. A (Ea), E. mathaei (Em), Echinometra sp. C (Ec), and E. oblonga (Eo). Planktotrophic larvae of all four species fed on cultured phytoplankton (Chaetoceros gracilis) attained metamorphic competence within 22-24 days after fertilization. Competent larvae were forced to delay metamorphosis for up to 5 months by preventing them from settling in culture bottles with continuous stirring on a set of 10 rpm rotating rollers and larval survival per monthly intervals was recorded. Larval survival was highest at 24 days, when competence was attained (0 delayed period), and there were no significant differences among the four species. Larvae that had experienced a prolonged delay had reduced survival rate, metamorphosis success, and juvenile survival, but among older larvae, Em had the highest success followed by Ea, Eo, and Ec. Juveniles from larvae of all four species that metamorphosed soon after becoming competent tended to have higher growth rates (test diameter and length of spines) than juveniles from larvae that metamorphosed after a prolonged period of competence with progressively slower growth the longer the prolonged period. Despite the adverse effects of delaying metamorphosis on growth parameters, competent larvae of all four species were able to survive up to 5 months and after metamorphosis grew into 1-month-old juveniles in lab condition. Overall, delayed larvae of Em showed significantly higher larval survival, metamorphosis, and juvenile survival than Ea and Eo, while Ec showed the lowest values in these performances. Em has the most widespread distribution of these species ranging from Africa to Hawaii, while Ec probably has the most restricted distribution. Consequently, differences in distribution may be related to differences in the ability to delay metamorphosis.
Fulltext Retracted: Luciferase-transfected colon adenocarcinoma cell line (DLD-1) for use in Orthotopic Xenotransplantation studies

Siddique MR, Shynder S, Ashraf MA, Yusoff I, Wajid A

Chem Cent J, 2012 Jul 18;6(1):69.
PMID: 22809083 DOI: 10.1186/1752-153X-6-69

BACKGROUND: Renilla Luciferase reporter gene (rLuc) GL4.82 and GL4.13 promoter are key player in transfection, but precise knowledge of its targets in colon cancer remains limited. The aim of this study was to characterize the best transfection technique to produce a stable transfected colon DLD1 (colorectal adenocarcinoma cell line), therefore imaging based approaches were employed.
RESULTS: DLD1 cells were transfected with a Plasmid (SV40-RLuc) carrying Renilla luciferase under the control of the SV-40 promoter, by using two different transfection techniques. Cells expressing the required DNA were isolated after antibiotic (Puramycin) selection. Clones of DLD-1/SV40-RLuc were produced using two different techniques (96 well plates and Petri dish) and their florescence intensity was recorded using IVIS machine (Calliper Life Sciences, Hopkinton, USA). Both techniques were characterized with the help of serial dilution technique. Results from this study substantiated that electroporation is the best. As expected, clones varied in their specific luciferase activity along with the dilutions. With the increase in cell concentration increase in intensity of florescence was recorded.
CONCLUSIONS: Based on the results we are confident that this transfected cell line DLD-1/SV40-RLuc (colorectal adenocarcinoma cell line) is the best for further Orthotopic Xenotransplantation Studies and in-vivo experiments as well. Investigation shows that DLD1/SV-rLuc cells have gained little bit resistance against both drugs therefore further study is suggested to know the reasons.
Paradigms unfolded - developing, validating, and evaluating the Medical Education e-Professionalism framework from a philosophical perspective

Guraya SS, Harkin DW, Yusoff MSB, Guraya SY

Front Med (Lausanne), 2023;10:1230620.
PMID: 37928467 DOI: 10.3389/fmed.2023.1230620

In order to ensure a strong research design, literature stresses the adoption of a research paradigm that is consistent with the researcher's beliefs about the nature of reality. In this article we provide an overview of research paradigm choices in relation to the creation of a Medical Education e-Professionalism (MEeP) framework discussing the research design, research methods, data collection and analysis to enhance the transparency of our previously published research. The MEeP framework was conceived to help Health Care Professionals (HCPs) safeguard the construct of professionalism in the digital context. This entire process was heavily informed by wider readings and deliberations of published literature on e-professionalism. Although the MEeP framework research journey has been published, the paradigms approach was not discussed in any detail. Considering that one of the duties of medical educator is to balance the service and science by bringing the theoretical underpinnings of one's research to public attention and scrutiny so as to nullify the notion of 'weak' research. We were compelled to unfold this paradigm story of the MEeP framework in a detailed manner. In an effort to make our research both robust and effective, this study portrays a philosophical approach to guide future research designs and methodological choices by detailing our rationale for pragmatism as a choice of paradigm.
Fulltext A study on the removal of propyl, butyl, and benzyl parabens via newly synthesised ionic liquid loaded magnetically confined polymeric mesoporous adsorbent

Md Yusoff M, Yahaya N, Md Saleh N, Raoov M

RSC Adv, 2018 Jul 16;8(45):25617-25635.
PMID: 35539765 DOI: 10.1039/c8ra03408g

This study investigated the effectiveness of ionic liquids (ILs) loaded onto the surface of a polymeric adsorbent (βCD-TDI) grafted with modified magnetic nanoparticles (MNPs) via an analysis of water treatment, which resulted in high removal of selected endocrine-disrupting chemicals (parabens). The syntheses of MNPs, MNP-βCD-TDI, and IL-MNP-βCD-TDI were characterised and compared using Fourier transform infrared (FT-IR) spectroscopy, carbon-hydrogen-nitrogen (CHN) analysis, vibrating sample magnetometry (VSM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), the Brunauer-Emmett-Teller (BET) method, thermogravimetric analysis (TGA), and X-ray diffraction (XRD). The results of SEM and TEM indicated that the pore size distribution exhibited mesoporous characteristics with a small surface area (BET analysis: 42.95 m2 g-1). Furthermore, a preliminary sorption experiment demonstrated the ability of IL-MNP-βCD-TDI to enhance not only the sorption capacity, but also the removal of propyl paraben (PP), butyl paraben (BP), and benzyl paraben (ArP). The adsorption process appeared to be pH-dependent, and hence the optimum pH of 6 was selected for a subsequent batch adsorption study of all the studied parabens with an equilibrium time of 80 min. Next, in an attempt to investigate the interactions that occur between the adsorbent and the adsorbates, adsorption kinetics and isotherm studies were performed. All the studied parabens were found to best fit pseudo-second-order kinetics and the Freundlich isotherm with R 2 > 0.98 at room temperature (298 K). The interaction of the host-guest inclusion complex and the π-π interaction between βCD and a selected paraben compound (ArP) were identified by performing 1H nuclear magnetic resonance (NMR), together with ultraviolet-visible (UV-vis) spectroscopic analysis. Finally, the adsorption efficiency of the developed material was practically tested on tap water, drain water, and industrial wastewater, which revealed a significant removal of parabens of up to 60-90% in comparison with a prior analysis.
Fulltext Prevalence of Latent Tuberculosis Infection and its Associated Factors Among Diabetic Patients Availing Primary Health Care in Terengganu State, Malaysia

Husain NF, Yusoff HM, Hassan NM, Aziz AA

Oman Med J, 2023 Sep;38(5):e546.
PMID: 38249131 DOI: 10.5001/omj.2023.97

OBJECTIVES: Diabetes mellitus (DM) patients are considered to be at high risk for contracting latent tuberculosis infection (LTBI). This study aimed to determine the prevalence of LTBI and its associated factors among diabetic patients attending primary care clinics in Terengganu state, Malaysia.
METHODS: This cross-sectional study was conducted among diabetic patients attending 11 health clinics in the Terengganu region from June 2017 to November 2018. The selected participants were administered a tuberculin skin test (TST). Simple and multivariate logistic regressions were applied to evaluate the significant associated factors of LTBI.
RESULTS: The total number of participants were 703 DM patients. The factors found associated with LTBI were poor diabetic control status (odds ratio (OR) = 8.53; p=0.008), being a healthcare worker (OR = 7.91; p=0.001), history of contact with TB patients (OR = 5.69; p < 0.001), bronchial asthma (OR = 5.28; p=0.019), coronary heart disease (OR = 3.45; p=0.026), and nephropathy (OR = 0.34; p=0.040). The presence of LTBI was found in 34 (4.8%) participants.
CONCLUSIONS: At 4.8%, the prevalence of LTBI among DM patients in Terengganu is relatively low. Diabetics with poorly controlled blood glucose levels, nephropathy, bronchial asthma, coronary heart disease, history of TB patient contact, or working in the healthcare profession should be periodically tested for LTBI.
Enhancement of biodegradation of crude petroleum-oil in contaminated water by the addition of nitrogen sources

Mukred AM, Hamid AA, Hamzah A, Yusoff WM

Pak J Biol Sci, 2008 Sep 01;11(17):2122-7.
PMID: 19266926

Addition of nitrogen sources as supplementary nutrient into MSM medium to enhance biodegradation by stimulating the growth four isolates, Acinetobacter faecalis, Staphylococcus sp., Pseudomonas putida and Neisseria elongata isolated from petroleum contaminated groundwater, wastewater aeration pond and biopond at the oil refinery Terengganu Malaysia was investigated. The organic nitrogen sources tested not only supported growth but also enhances biodegradation of 1% Tapis crude oil. All four isolates showed good growth especially when peptone was employed as the organic nitrogen compared to growth in the basal medium. Gas chromatography showed that more then 91, 93, 94 and 95% degradation of total hydrocarbon was observed after 5 days of incubation by isolates Pseudomonas putida, Neisseria elongate, Acinetobacter faecalis and Staphylococcus sp., respectively.
Effect of some environmental parameters on hydrogen production using C. acetobutylicum

Alshiyab H, Kalil MS, Hamid AA, Yusoff WM

Pak J Biol Sci, 2008 Sep 01;11(17):2073-82.
PMID: 19266920

The aim of this study was to investigate the influence of some environmental factors on bacterial metabolism. Fermentative hydrogen production by C. acetobutylicum, using glucose as the substrate. The effect of initial pH (4-8), inoculum size (1-20% (v/v)) and glucose concentration (1-30 g L(-1)) on hydrogen production were studied. The optimum cultivation temperature for hydrogen production was at 30 degrees C. The results show that substrate concentration and inoculum size resulted in hydrogen yield (Y(P/S)) of 391 mL g(-1) glucose utilized with maximum hydrogen productivity of 77.5 mL/L/h. Higher substrate concentration or inoculum size adversely affects hydrogen production, which decreases hydrogen yield by 15% to 334 mL g(-1) glucose utilized when 30% (v/v) inoculum size was used. The use of 30 g L(-1) substrate concentration resulted in a 75% decrease to 97 mL g(-1) glucose supplied. Concluded that proper Xo/So enhanced the hydrogen production.
Removal of headspace CO2 increases biological hydrogen production by C. acetobutylicum

Alshiyab H, Kalil MS, Hamid AA, Yusoff WM

Pak J Biol Sci, 2008 Oct 01;11(19):2336-40.
PMID: 19137867

The effect of removal of resultant gas resulted in enhancement of the H2 yield. The technique of CO2 scavenging resulted in H2 yield being improved from 408 mL g(-1) to reach the maximum of 422 mL g'. The highest hydrogen productivity of 87.9 ml L(-1) h(-1) was obtained by CO2 scavenging. Biomass concentration was enhanced to 1.47 g L(-1), Y(P,X) of 287 ml g(-1) L(-1), Y(X/S) of 0.294 and Y(H2/s) of 0.0377 by the use of CO2 scavenging. The results suggested that the presence of the gaseous products in fermentation medium and headspace adversely effect biomass growth and hydrogen production.
Effect of salts addition on hydrogen production by C. acetobutylicum

Alshiyab H, Kalil MS, Hamid AA, Wan Yusoff WM

Pak J Biol Sci, 2008 Sep 15;11(18):2193-200.
PMID: 19137827

The objective of this study is to investigate the effect of salts addition to fermentation medium on hydrogen production, under anaerobic batch culture system. In this study, batch experiments were conducted to investigate the inhibitory effect of both NaCl and sodium acetate on hydrogen production. The optimum pH and temperature for hydrogen production were at initial pH of 7.0 and 30 degrees C. Enhanced production of hydrogen, using glucose as substrate was achieved. In the absence of Sodium Chloride and Sodium Acetate enhanced hydrogen yield (Y(P/S)) from 350 mL g(-1) glucose utilized to 391 mL g(-1) glucose utilized with maximum hydrogen productivity of 77.5 ml/L/h. Results also show that sodium chloride and sodium acetate in the medium adversely affect growth. Hydrogen yield per biomass (Y(P/X)) of 254 ml/L/g, biomass per substrate utilized (Y(X/S)) of 0.268 and (Y(H2/S) of 0.0349. The results suggested that Sodium at any concentration resulted to inhibit the bacterial productivity of hydrogen.
Growth enhancement of effective microorganisms for bioremediation of crude oil contaminated waters

Mukred AM, Abd-Hamid A, Hamzah A, Yusoff WM

Pak J Biol Sci, 2008 Jul 01;11(13):1708-12.
PMID: 18819623

The bioremediation of polluted groundwater, wastewater aeration pond and biopond sites was investigated using bacteria isolated from these sites located at the oil refinery Terengganu Malaysia. Out of 62 isolates, only 16 isolates from groundwater (8) and wastewater aeration pond (3) and biopond (5) were chosen based on growth medium containing 1% (v/v) Tapis crude oil. Only four isolates; Acinetobacter faecalis, Staphylococcus sp., Pseudomonas putida and Neisseria elongata showed percentage biodegradation of crude oil more than 50% after 5 days using Mineral Salts Medium (MSM). The effect of physical parameters (temperature, pH and agitation) on growth by all four strains showed a maximum growth in MSM medium with 1% Tapis crude oil at 37 degrees C with pH 7 and agitation of 130 rpm.
Studies on extraction of mannanase enzyme by Aspergillus terreus SUK-1 from fermented palm kernel cake

Rashid JI, Samat N, Yusoff WM

Pak J Biol Sci, 2013 Sep 15;16(18):933-8.
PMID: 24502150

Microbial mannanases have become biotechnologically important in industry but their application is limited due to high production cost. In presents study, the extraction of mannanase from fermented Palm Kernel Cake (PKC) in the Solid State Fermentation (SSF) was optimized. Local isolate of Aspergillus terreus SUK-1 was grown on PKC in (SSF) using column bioreactor. The optimum condition were achieved after two washes of fermented PKC by adding of 10% glycerol (v/v) soaked for 10 h at the room temperature with solvent to ratio, 1:5 (w/v).
Effect of some environmental parameters on biobutanol production by Clostridium acetobutylicum NCIMB 13357 in date fruit medium

Khamaiseh EI, Hamid AA, Yusoff WM, Kalil MS

Pak J Biol Sci, 2013 Oct 15;16(20):1145-51.
PMID: 24506014

Date fruit juice contains high concentration of simple sugars ranging from 65 to 75% (w/w) in dry form. In this study, the potential of date fruit juice as biobutanol fermentation medium by C. acetobutylicum was investigated. The fermentation process was carried out at initial pH of 5, 6 and 7, incubation temperature of 30, 35 and 40 degrees C for 72 hours. The date fruit concentrations tested were 10, 20, 30 and 40 g L(-1). Medium containing 30 g L(-1) of date fruit at 35 degrees C incubation temperature with initial medium pH 7.0 gave the highest concentration of solvents of 3.1, 0.1 and 1.1 g L(-1) butanol, ethanol and acetone respectively. The yield and productivity of biobutanol were 0.32 g g(-1) and 0.044 g L(-1)/h respectively, while for total ABE were 0.45 g g(-1) and 0.06 g L(-1) h, respectively.
Optimization of temperature, moisture content and inoculum size in solid state fermentation to enhance mannanase production by Aspergillus terreus SUK-1 using RSM

Rashid JI, Samat N, Mohtar W, Yusoff W

Pak J Biol Sci, 2011 May 01;14(9):533-9.
PMID: 22032082

Optimization of three parameters, temperature (25-35 degrees C), moisture content (40% (w/v)-60% (w/v) and inoculum sizes (5% (w/v)-15% (w/v) were investigated and optimized by Response Surface Methodology (RSM) for optimal mannanase production by Aspergillus terreus SUK-1. A second order polynomial equation was fitted and the optimum condition was established. The result showed that the moisture content was a critical factor in terms of its effect on mannanase. The optimum condition for mannanase production was predicted at 42.86% (w/v) initial moisture (31 C) temperature and 5.5% (w/v) inoculum size. The predicted optimal parameter were tested in the laboratory and the mannanase activity 45.12 IU mL-1 were recorded to be closed to the predicted value (44.80 IU mL-1). Under the optimized SSF condition (31 degrees C, 42.86% moisture content (w/v) and 5.5% inoculum size (w/v)), the maximum mannanase production was to prevail about 45.12 IU mL-1 compare to before optimized (30 degrees C, 50% moisture content (w/v) and 10% inoculum size (w/v)) was only 34.42 IU mL-1.
Fulltext Histopathological Alterations in Gills, Liver and Kidney of African Catfish (Clarias gariepinus, Burchell 1822) Exposed to Melaleuca cajuputi Extract

Hassan M, Melad AAN, Zakariah MI, Yusoff NAH

Trop Life Sci Res, 2023 Jun;34(2):177-196.
PMID: 38144386 DOI: 10.21315/tlsr2023.34.2.9

This study evaluated the histopathological changes in the gill, liver and kidney of African catfish (Clarias gariepinus) intoxicated with a sub-lethal dose of Melaleuca cajuputi leaves extract (MCLE) for 96 h. The acute toxicity test has been determined previously with a value of 96-h LC50 = 127 mg/L, hence the selection of sub-lethal ranges from 60 mg/L to 160 mg/L of MCLE. Degenerative alterations were prominent in all tested organs, particularly after exposure to a high concentration of MCLE. Gill exhibited haemorrhage, epithelial lifting, lamellar disorganisation, and necrosis after exposure to a high MCLE concentration. Alterations in the liver include congestion, hydropic degeneration, and vacuolation, whereas lesions in the kidney were pyknosis, vacuolation, hydropic degeneration, and tubular necrosis. The obtained data showed that the organs experienced severe changes proportional to the increase in MCLE concentration. In addition, fish exposed to higher concentrations than the LC50 value experienced irreversible lesions. The present study suggests that the use of MCLE below the LC50 is recommended to avoid severe alterations to organs, particularly in African catfish. This study demonstrated that the use of MCLE above the LC50 promotes severe damage to the gills, liver and kidney of African catfish. However, further investigations are needed to define the causing-mechanisms underlying these effects.

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