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Oil palm empty fruit bunch as alternative substrate for acetone-butanol-ethanol production by Clostridium butyricum EB6

Ibrahim MF, Abd-Aziz S, Razak MN, Phang LY, Hassan MA

Appl Biochem Biotechnol, 2012 Apr;166(7):1615-25.
PMID: 22391689 DOI: 10.1007/s12010-012-9538-6

Acetone-butanol-ethanol (ABE) production from renewable resources has been widely reported. In this study, Clostridium butyricum EB6 was employed for ABE fermentation using fermentable sugar derived from treated oil palm empty fruit bunch (OPEFB). A higher amount of ABE (2.61 g/l) was produced in a fermentation using treated OPEFB as the substrate when compared to a glucose based medium that produced 0.24 g/l at pH 5.5. ABE production was increased to 3.47 g/l with a yield of 0.24 g/g at pH 6.0. The fermentation using limited nitrogen concentration of 3 g/l improved the ABE yield by 64%. The study showed that OPEFB has the potential to be applied for renewable ABE production by C. butyricum EB6.
Fulltext Bioconversion of glycerol for bioethanol production using isolated Escherichia coli ss1

Suhaimi SN, Phang LY, Maeda T, Abd-Aziz S, Wakisaka M, Shirai Y, et al.

Braz J Microbiol, 2012 Apr;43(2):506-16.
PMID: 24031858 DOI: 10.1590/S1517-83822012000200011

Bioconverting glycerol into various valuable products is one of glycerol's promising applications due to its high availability at low cost and the existence of many glycerol-utilizing microorganisms. Bioethanol and biohydrogen, which are types of renewable fuels, are two examples of bioconverted products. The objectives of this study were to evaluate ethanol production from different media by local microorganism isolates and compare the ethanol fermentation profile of the selected strains to use of glucose or glycerol as sole carbon sources. The ethanol fermentations by six isolates were evaluated after a preliminary screening process. Strain named SS1 produced the highest ethanol yield of 1.0 mol: 1.0 mol glycerol and was identified as Escherichia coli SS1 Also, this isolated strain showed a higher affinity to glycerol than glucose for bioethanol production.
Lipase-catalyzed dimethyl adipate synthesis: response surface modeling and kinetics

Chaibakhsh N, Rahman MB, Basri M, Salleh AB, Abd-Aziz S

Biotechnol J, 2010 Aug;5(8):848-55.
PMID: 20632329 DOI: 10.1002/biot.201000063

Dimethyl adipate (DMA) was synthesized by immobilized Candida antarctica lipase B-catalyzed esterification of adipic acid and methanol. To optimize the reaction conditions of ester production, response surface methodology was applied, and the effects of four factors namely, time, temperature, enzyme concentration, and molar ratio of substrates on product synthesis were determined. A statistical model predicted that the maximum conversion yield would be 97.6%, at the optimal conditions of 58.5 degrees C, 54.0 mg enzyme, 358.0 min, and 12:1 molar ratio of methanol to adipic acid. The R(2) (0.9769) shows a high correlation between predicted and experimental values. The kinetics of the reaction was also investigated in this study. The reaction was found to obey the ping-pong bi-bi mechanism with methanol inhibition. The kinetic parameters were determined and used to simulate the experimental results. A good quality of fit was observed between the simulated and experimental initial rates.
Immunomodulatory effects of zerumbone isolated from roots of Zingiber zerumbet

Keong YS, Alitheen NB, Mustafa S, Abdul Aziz S, Abdul Rahman M, Ali AM

Pak J Pharm Sci, 2010 Jan;23(1):75-82.
PMID: 20067871

In this study, the immunomodulatory effects of zerumbone isolated from Zingiber zerumbet were investigated by evaluating the effects of this compound towards the lymphocytes proliferation (mice thymocytes, mice splenocytes and human human peripheral blood mononuclear cells, PBMC), cell cycle progression and cytokine (interleukin 2 and 12) induction. Lymphocyte proliferation assay showed that zerumbone was able to activate mice thymocytes, splenocytes and PBMC at dosage dependent pattern where the best concentration was 7.5 microg/ml. Flow cytometry analysis showed the highest population of PBMC entered into G2/M phase after treatment for 72 h with 7.5 microg/ml zerumbone. The production of human interleukin-2 and human interleukin-12 cytokines in culture supernatant from zerumbone activated lymphocytes was prominently upregulated at 24 hour and decreased from 48 h to 72 h. The above results indicate that zerumbone can be used as immunomodulatory agent which can react toward the immune cell cytokine production in dosage dependent pattern.
Fulltext Comparison between the panoptic ophthalmoscope and the conventional direct ophthalmoscope in the detection of sight threatening diabetic retinopathy: the kuching diabetic eye study

Tan AK, Mallika P. S., Aziz S, Asokumaran T, Intan G, Faridah HA

Malays Fam Physician, 2010;5(2):83-90.
PMID: 25606193 MyJurnal

OBJECTIVE: To determine the sensitivity and specificity of the conventional direct ophthalmoscope and the PanOptic ophthalmoscope in the detection of sight threatening retinopathy, as well as the "Ease of Use" of these equipments.
METHODS: 200 diabetics, newly referred from primary health physicians were examined. Fundus examinations were performed with pupil dilatation in a dark room. The examinations were performed by a single investigator using the PanOptic ophthalmoscope, the conventional direct ophthalmoscope and slit lamp biomicroscopy.
RESULTS: The overall sensitivity in detecting sight threatening retinopathy using the conventional direct ophthalmoscope was 73.2% (95% CI: 57.1-85.8%), specificity 93.7% (95% CI: 88.7-96.9%). For PanOptic ophthalmoscope, the overall sensitivity in detecting sight threatening retinopathy was 58.5% (95% CI: 42.1-73.7%), specificity 93.7% (95% CI: 88.7-96.9%). The conventional direct ophthalmoscope was 1.38 times (95% CI: 1.17-1.61 times) as easy to use compared to the PanOptic ophthalmoscope.
CONCLUSION: The PanOptic ophthalmoscope is not superior to the conventional direct ophthalmoscope for the screening of Sight Threatening Retinopathy.
KEYWORDS: PanOptic ophthalmoscope; conventional direct ophthalmoscope; sight threatening retinopathy
Study site: Ophthalmology clinic, Sarawak General Hospital, Kuching, Sarawak, Malaysia
Effect of agitation and aeration rates on chitinase production using Trichoderma virens UKM1 in 2-l stirred tank reactor

Abd-Aziz S, Fernandez CC, Salleh MM, Illias RM, Hassan MA

Appl Biochem Biotechnol, 2008 Aug;150(2):193-204.
PMID: 18633736 DOI: 10.1007/s12010-008-8140-4

Shrimps have been a popular raw material for the burgeoning marine and food industry contributing to increasing marine waste. Shrimp waste, which is rich in organic compounds is an abundant source of chitin, a natural polymer of N-acetyl-D-glucosamine (GluNac), a reducing sugar. For this respect, chitinase-producing fungi have been extensively studied as biocontrol agents. Locally isolated Trichoderma virens UKM1 was used in this study. The effect of agitation and aeration rates using colloidal chitin as control substrate in a 2-l stirred tank reactor gave the best agitation and aeration rates at 200 rpm and 0.33 vvm with 4.1 U/l per hour and 5.97 U/l per hour of maximum volumetric chitinase activity obtained, respectively. Microscopic observations showed shear sensitivity at higher agitation rate of the above system. The oxygen uptake rate during the highest chitinase productivity obtained using sun-dried ground shrimp waste of 1.74 mg of dissolved oxygen per gram of fungal biomass per hour at the kappaL a of 8.34 per hour.
Risk factors of erectile dysfunction in patients receiving methadone maintenance therapy

Nik Jaafar NR, Mislan N, Abdul Aziz S, Baharudin A, Ibrahim N, Midin M, et al.

J Sex Med, 2013 Aug;10(8):2069-76.
PMID: 23445463 DOI: 10.1111/jsm.12105

INTRODUCTION: While methadone effectively treats opiate dependence, the side effect of erectile dysfunction (ED) may interfere with treatment adherence and benefits.
AIM:To determine the rate of ED and the associated factors which predict ED in male patients on methadone maintenance therapy (MMT) in a Malaysian population.
MAIN OUTCOME MEASURES: The main outcome measures were the International Index of Erectile Function-15 (IIEF-15) and the Beck Depression Inventory (BDI).
METHODS: A total of 108 participants diagnosed with heroin dependence were assessed. We used the Structured Clinical Interview for DSM-IV Axis-I Disorders (SCID-I) on subjects who received MMT, and they were assessed using the IIEF-15, the BDI, and measures of other clinical and sociodemographic variables.
RESULTS: The rate of ED among men on MMT was 68.5% (mild ED, 36.1%; mild to moderate ED, 22.2%; severe ED, 3.7%). The mean age of the participants was 43.45 years. Older age (P = 0.002), concurrent illicit heroin use (P = 0.024), and having an older partner (P = 0.039) were significantly associated with ED. Following multivariate analysis, it was found that older age was the only significant predictor of ED, with an adjusted odds ratio of 1.07 (95% CI = 1.02-1.16). Methadone dose and duration of methadone treatment were not significantly associated with ED.
CONCLUSION: ED was highly prevalent among male patients on MMT. This suggests that there is a need for routine assessment of sexual function in patients on methadone. Among the risk factors, age was the only factor that was significantly associated with ED. The current use of MMT in Malaysia in terms of dosage and duration did not pose a significant risk for ED.
KEYWORDS: Erectile Dysfunction; Methadone Therapy; Opiate Dependence
Study site: outpatient clinic for opiate substitution therapy, Hospital Kuala Lumpur (HKL), Malaysia
Improvement of cyclodextrin glycosyltransferase gene expression in Escherichia coli by insertion of regulatory sequences involved in the promotion of RNA transcription

Ramli N, Abd-Aziz S, Alitheen NB, Hassan MA, Maeda T

Mol Biotechnol, 2013 Jul;54(3):961-8.
PMID: 23338983 DOI: 10.1007/s12033-013-9647-7

Regulation of RNA transcription in controlling the expression of genes at promoter and terminator regions is crucial as the interaction of RNA polymerase occurred at both sites. Gene encoding cyclodextrin glycosyltransferase (CGTase) from Bacillus sp. NR5 UPM isolated in the previous study was used for further construction of pTZCGT-SS, pTZCGT-BS and pTZCGT-BT expression systems for enhancement of CGTase production. The putative promoter regions, -35 and -10 sequences were found in the upstream of the mature gene start codon. Whereas, long inverted repeats sequences which can form a stable stem and loop structure was found downstream of the open reading frame (ORF) of Bacillus sp. NR5 UPM CGTase. The construction of E. coli strain harbouring pTZCGT-BS showed increment of 3.2-fold in CGTase activity compared to the wild type producer. However, insertion of terminator downstream of CGTase gene in E. coli strain harbouring pTZCGT-BT only resulted in 4.42 % increment of CGTase production compared to E. coli strain containing pTZCGT-BS, perhaps due to low intrinsic termination efficiency. Thus, it is suggested that the insertion of the putative promoter regions upstream of the coding sequence for the construction of CGTase expression system will further enhance in the recombinant enzyme production.
Fulltext Comparison on the use of semi-automated and automated core biopsy needle in ultrasound guided breast biopsy

Sridharan R, Yunos SM, Aziz S, Hussain RI, Alhabshi SM, Suria Hayati MP, et al.

Med J Malaysia, 2015 Dec;70(6):326-33.
PMID: 26988204 MyJurnal

OBJECTIVE: The aim of this study was to compare the use of semi-automated (Medax Velox 2; Poggio Rusco, Italy) and automated (Bard Magnum Biopsy Instrument; Covington, GA, USA) core biopsy needles, for ultrasound guided breast biopsy.
MATERIALS AND METHODS: A 14G semi-automatic spring loaded core biopsy needle with a 22-mm-throw (Medax Velox 2; Poggio Rusco, Italy) and 14-gauge automated needle device with a 22-mm-throw biopsy gun (Bard-Magnum Biopsy Instrument, Covington, GA, USA) were used for breast biopsies under ultrasound guidance on alternate months during the study period between July 2009 and May 2011. One hundred and sixty lesions were biopsied and specimens were sent for histological evaluation.
RESULTS: The automated needle obtained a higher number of histology reports at 84% (67/80) as compared with the semiautomated needle at 60% (48/80) (Fisher exact test, p value=0.023). Inadequate samples with the automated needle were much less at 9% (7/60) than with the semiautomated needle at 23% (18/60) (Fisher exact test, p value=0.028). The semi-automated needle showed slightly less fragmented samples. However, the number of fragmented samples with definitive diagnosis was slightly higher with the automated compared with the semiautomated needle, at 16% (13/80) and 13% (10/80) respectively. Compared with histology of 29 lesions that were excised, the semi-automated needle had higher sensitivity (100%) but lower specificity (75%) and accuracy (90%) compared with the automated needle (88% sensitivity, 100% specificity, 95% accuracy).
CONCLUSION: Definitive diagnosis from the study samples slightly favours the use of automated core biopsy needle as compared to semi-automated core biopsy needle.
Study site: Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur
Fulltext MH17: the Malaysian experience

Khoo LS, Hasmi AH, Abdul Ghani Aziz SA, Ibrahim MA, Mahmood MS

Malays J Pathol, 2016 Apr;38(1):1-10.
PMID: 27126658 MyJurnal

A disaster is a natural or man-made (or technological) hazard resulting in an event of substantial extent causing significant physical damage or destruction, loss of life, or drastic change to the environment. It is a phenomenon that can cause damage to life and property and destroy the economic, social and cultural life of the people; and overwhelms the capacity of the community to cope with the event. The recent tragic aviation accidents in 2014 involving Malaysia Airlines flights MH370 and MH17 shocked the world in an unprecedented manner. This paper focuses on the Malaysian experience in the MH17 mission in Ukraine as well as the first ever international Disaster Victim Identification (DVI) operation for the Malaysian DVI team. The DVI operations in Hilversum, the Netherlands were well described in stages. The Netherlands' Landelijk Team Forensische Opsporing as the lead DVI team in Hilversum operated systematically, ensuring the success of the whole mission. This paper discusses the lessons learned by the Malaysian team on proper DVI structure, inter- and intra-agency cooperation, facilities planning and set up, logistics and health and safety aspects, as well as effective communication and collaboration with other international delegates. Several issues and challenges faced by the Malaysian team were also documented. In addition, the authors shared views, opinions and recommendations for a more comprehensive DVI operation in the future.
Case-control investigation on the risk factors of melioidosis in small ruminant farms in Peninsular Malaysia

Musa HI, Hassan L, Shamsuddin ZH, Panchadcharam C, Zakaria Z, Abdul Aziz S, et al.

J Appl Microbiol, 2015 Aug;119(2):331-41.
PMID: 25891038 DOI: 10.1111/jam.12830

Epidemiology of melioidosis is poorly understood because its occurrence is influenced by complex interaction of environmental, climatic, physicochemical and host factors. We investigated the potential risk factors for the exposure to Burkholderia pseudomallei in small ruminants' farms in Peninsular Malaysia.
Potential non-phytopathogenic filamentous fungi for bioconversion of domestic wastewater sludge

Molla AH, Fakhru'l-Razi A, Hanafi MM, Abd-Aziz S, Alam MZ

J Environ Sci Health A Tox Hazard Subst Environ Eng, 2002 Sep;37(8):1495-507.
PMID: 12369641

Ten filamentous fungi adapted to domestic wastewater sludge (DWS) were further studied to evaluate their potential in terms of adaptation to higher sludge supplemented growing media and phytopathogenicity (induction of diseases to plants) to three germinating crop (Corn: Zea mays, Mung bean: Phaseolus aureus and Mustard: Brassica napus) seeds. The performances of the fungi in seed germination were evaluated based on percent germination index (GI) and infected/spotted seeds on direct fungal biomass (FBM) and fungal metabolite (FM). Significantly the highest biomass production was achieved with RW-P1 512 and Penicillium corylophilum (WW-P1003) at the highest (25%) sludge supplemented growing media that implied its excellent potentiality of adaptation and multiplication to domestic wastewater sludge. Significantly encouraging results of percent GI and spotted/infected seedlings were observed in FM than FBM by all fungi except the strain Aspergillus niger. A. niger gave the poorest percent of GI (24.30, 26.98 and 00.00%) and the highest percent of infected/spotted seeds (70, 100, and 100%) using FBM for corn, mung bean and mustard, respectively. On the other hand, comparatively the highest percent of GI (107.99, 106.25 and 117.67%) and the lowest percent of spotted/infected seedlings (3.3, 3.3 and 3.3%) were achieved with the isolate RW-P1 512 using FM. In FBM, the superior results of percent GI (86.61, 95.92 and 83.87%) and spotted/infected seedlings (3.3, 63.3 and 43.3%) were obtained by A. versicolor. Several crop seeds were responded differently for different fungal treatments. Hundred percent infected/spotted seeds in FM were recorded only for mustard with Trichoderma family that implied its strong sensitiveness to its metabolites.
A potential resource for bioconversion of domestic wastewater sludge

Molla AH, Fakhru'l-Razi A, Abd-Aziz S, Hanafi MM, Roychoudhury PK, Alam MZ

Bioresour Technol, 2002 Dec;85(3):263-72.
PMID: 12365494

Twenty seven filamentous fungal strains representing five genera; Aspergillus, Penicillium, Trichoderma, Myriodontium and Pleurotus were isolated from four sources; domestic wastewater sludge cake (SC) from IWK (Indah Water Konsortium) wastewater treatment plant, palm oil mill effluent compost from Sri Ulu palm Oil Processing Mill, compost of plant debris, and fungal fruiting bodies from a rotten wood stump. Thirty-three strains/isolates were tested for their ability to convert domestic wastewater sludge into compost by assessing biomass production and growth rate on sludge enriched media. The strains/isolates Aspergillus niger, SS-T2008, WW-P1003 and RW-P1 512 produced the highest dry biomass at higher sludge supplemented culture media from their respective group (Aspergillus, Trichoderma, Penicillium and Basidiomycetes, respectively). This implied these strains are better adapted for growth at higher sludge rich substances, and subsequently may be efficient in bioconversion/biodegradation of sludge. The fungi isolated from ecological closely related sources were more amendable to adaptation in a sludge rich culture media.
Fulltext Prevalence of Staphylococcus aureus carriage by young Malaysian footballers during indoor training

William JL, Radu S, Aziz SA, Rahim RA, Cheah YK, Liwan A, et al.

Br J Sports Med, 2004 Feb;38(1):12-4.
PMID: 14751938

BACKGROUND: Research has shown that athletes are carriers of Staphylococcus aureus during physical activity.
OBJECTIVE: To estimate the mean total plate count of S aureus carried by footballers before and after training at an indoor venue.
METHODS: Forty Malay and 20 Indian students volunteered to participate. There was also a control group consisting of 40 Malay and 20 Indian students who were not active. The experimental group were active footballers who had played at school or club level. The subjects were healthy and free of skin infection. The experiment was divided into three sessions, with 20 subjects present at each. At each session, the subjects trained for one hour. Swabs were taken from the skin, nose, and ear before and after training. For the control group, swabs were taken only once from the skin, nose, and ear. The swabs were subjected to biochemical tests and then streaked and cultured aerobically in Baird Parker agar plates for 24 hours at 37 degrees C. Black colonies with a clear zone were presumed to be S aureus, and the mean total plate count of the colonies was estimated. Gram staining, catalase, coagulase slide, coagulase tube, acetoin production, o-nitrophenyl beta-D-galactopyranoside (ONPG), and mannitol fermentation tests were used to confirm the colonies as S aureus. A haemolysin test was conducted with human blood to confirm haemolytic activity.
RESULTS: All subjects in the experimental group were carrying S aureus both before and after training. The estimated mean total counts of colonies from the skin, ear, and nose for the Malays before training were 33, 71, and 312 respectively. Counts after training were 21, 44, and 452 respectively. The results for the Indians were 72, 80, and 309 respectively before training and 55, 200, and 466 respectively after training. The positive results for Gram staining, catalase, coagulase slide, coagulase tube, acetoin production, ONPG, and mannitol fermentation tests were 100%, 96%, 95%, 95%, 93%, 93%, and 90% respectively. All subjects in the control group were also carrying S aureus.
CONCLUSIONS: All of the players were carriers of S aureus during training. The decrease in total count from the skin for both races may be due to lysozyme activity lysing the bacterial cells. Contamination of the environment with these bacteria may have increased the estimated total plate count in the nose. The experimental group face a higher risk of infection because of lower immunity during training and higher rate of injuries compared with the control group.
Harnessing the potential of ligninolytic enzymes for lignocellulosic biomass pretreatment

Masran R, Zanirun Z, Bahrin EK, Ibrahim MF, Lai Yee P, Abd-Aziz S

Appl Microbiol Biotechnol, 2016 Jun;100(12):5231-46.
PMID: 27115758 DOI: 10.1007/s00253-016-7545-1

Abundant lignocellulosic biomass from various industries provides a great potential feedstock for the production of value-added products such as biofuel, animal feed, and paper pulping. However, low yield of sugar obtained from lignocellulosic hydrolysate is usually due to the presence of lignin that acts as a protective barrier for cellulose and thus restricts the accessibility of the enzyme to work on the cellulosic component. This review focuses on the significance of biological pretreatment specifically using ligninolytic enzymes as an alternative method apart from the conventional physical and chemical pretreatment. Different modes of biological pretreatment are discussed in this paper which is based on (i) fungal pretreatment where fungi mycelia colonise and directly attack the substrate by releasing ligninolytic enzymes and (ii) enzymatic pretreatment using ligninolytic enzymes to counter the drawbacks of fungal pretreatment. This review also discusses the important factors of biological pretreatment using ligninolytic enzymes such as nature of the lignocellulosic biomass, pH, temperature, presence of mediator, oxygen, and surfactant during the biodelignification process.
Fulltext Combination of Superheated Steam with Laccase Pretreatment Together with Size Reduction to Enhance Enzymatic Hydrolysis of Oil Palm Biomass

Ahmad Rizal NFA, Ibrahim MF, Zakaria MR, Kamal Bahrin E, Abd-Aziz S, Hassan MA

Molecules, 2018 Apr 02;23(4).
PMID: 29614823 DOI: 10.3390/molecules23040811

The combination of superheated steam (SHS) with ligninolytic enzyme laccase pretreatment together with size reduction was conducted in order to enhance the enzymatic hydrolysis of oil palm biomass into glucose. The oil palm empty fruit bunch (OPEFB) and oil palm mesocarp fiber (OPMF) were pretreated with SHS and ground using a hammer mill to sizes of 2, 1, 0.5 and 0.25 mm before pretreatment using laccase to remove lignin. This study showed that reduction of size from raw to 0.25 mm plays important role in lignin degradation by laccase that removed 38.7% and 39.6% of the lignin from OPEFB and OPMF, respectively. The subsequent saccharification process of these pretreated OPEFB and OPMF generates glucose yields of 71.5% and 63.0%, which represent a 4.6 and 4.8-fold increase, respectively, as compared to untreated samples. This study showed that the combination of SHS with laccase pretreatment together with size reduction could enhance the glucose yield.
Fulltext Salmonella in native "village" chickens (Gallus domesticus): prevalence and risk factors from farms in South-Central Peninsular Malaysia

Jajere SM, Hassan L, Abdul Aziz S, Zakaria Z, Abu J, Nordin F, et al.

Poult Sci, 2019 Nov 01;98(11):5961-5970.
PMID: 31392329 DOI: 10.3382/ps/pez392

Village chicken or Ayam Kampung, common to Southeast Asian countries, has always been regarded as superior in comparison to commercial broiler chicken in terms of wholesomeness and health benefits. The current study investigates the prevalence and risk factors of Salmonella among village chicken flocks from the central and southern states of Peninsular Malaysia. A total of 35 village flocks were sampled from Selangor (n = 19), Melaka (n = 10), Johor (n = 4), and Negeri Sembilan (n = 2). In total, 1,042 samples were collected; these included cloacal swabs (n = 675), eggs (n = 62), pooled drinking water (n = 175), pooled feeds (n = 70), and pooled flies (n = 60). Isolation of Salmonella from cloacal swabs, poultry drinking water, and feeds was carried out according to the protocols and recommendations of the World Organization for Animal Health (OIE) terrestrial manual. The prevalence of Salmonella at an individual bird-level was 2.5% (17/675, 95% CI: 1.6 to 4.0). All eggs screened were negative; in the case of environmental samples, however, Salmonella was detected in 5.14% (9/175), 7.14% (5/70), and 5.0% (3/60) for water, feed, and flies, respectively. A total of 34 isolates and 8 Salmonella serotypes were identified. Weltevreden (20.6%) was the most common, followed by Typhimurium and Agona (17.6%), Albany and Enteritidis (8.8%), Molade (5.9%), Corvallis and Schleissheim (2.9%), and others grouped as Salmonella spp. (11.8%). Multivariable logistic regression models revealed that Salmonella positivity among flocks could be strongly predicted by storage of feeds (uncovered feeds; OR = 10.38; 95% CI: 1.25 to 86.39; p = 0.030) and uncovered water tanks (uncovered tank; OR = 6.43; 95% CI: 1.02 to 40.60; p = 0.048). The presence of Salmonella in village chickens in the study area was lower than that of commercial chickens in Malaysia.
Optimized lipase-catalyzed synthesis of adipate ester in a solvent-free system

Chaibakhsh N, Abdul Rahman MB, Abd-Aziz S, Basri M, Salleh AB, Abdul Rahman RN

J Ind Microbiol Biotechnol, 2009 Sep;36(9):1149-55.
PMID: 19479288 DOI: 10.1007/s10295-009-0596-x

Immobilized Candida antarctica lipase-catalyzed esterification of adipic acid and oleyl alcohol was investigated in a solvent-free system (SFS). Optimum conditions for adipate ester synthesis in a stirred-tank reactor were determined by the response surface methodology (RSM) approach with respect to important reaction parameters including time, temperature, agitation speed, and amount of enzyme. A high conversion yield was achieved using low enzyme amounts of 2.5% w/w at 60 degrees C, reaction time of 438 min, and agitation speed of 500 rpm. The good correlation between predicted value (96.0%) and actual value (95.5%) implies that the model derived from RSM allows better understanding of the effect of important reaction parameters on the lipase-catalyzed synthesis of adipate ester in an organic solvent-free system. Higher volumetric productivity compared to a solvent-based system was also offered by SFS. The results demonstrate that the solvent-free system is efficient for enzymatic synthesis of adipate ester.
Fulltext The Study of the Degree of Crystallinity, Electrical Equivalent Circuit, and Dielectric Properties of Polyvinyl Alcohol (PVA)-Based Biopolymer Electrolytes

B Aziz S, S Marf A, Dannoun EMA, Brza MA, Abdullah RM

Polymers (Basel), 2020 Sep 24;12(10).
PMID: 32987807 DOI: 10.3390/polym12102184

This report presents a facile and efficient methodology for the fabrication of plasticized polyvinyl alcohol (PVA):chitosan (CS) polymer electrolytes using a solution cast technique. Regarding characterizations of electrical properties and structural behavior, the electrochemical impedance spectroscopy (EIS) and X-ray diffraction (XRD) are used, respectively. Crystalline peaks appear in the XRD pattern of the PVA:CS:NH4I while no peaks can be seen in the XRD pattern of plasticized systems. The degree of crystallinity is calculated for all the samples from the deconvoluted area of crystalline and amorphous phases. Considering the EIS measurements, the most conductive plasticized system shows a relatively high conductivity of (1.37 × 10-4) S/cm, which is eligible for applications in energy storage devices. The analysis of the EIS spectra reveals a decrease in bulk resistance which indicates an increase in free ion carriers. The electrical equivalent circuit (EEC) model is used in the analysis of EIS plots. Dielectric properties are modified with the addition of glycerol as a plasticizer. It is proved that the addition of glycerol as a plasticizer lowers ion association. It also shows, at the low-frequency region, a large value of a dielectric constant which is correlated with electrode polarization (EP). The distribution of relaxation times is associated with conducting ions.
Fulltext In vitro cytotoxic and antimicrobial activities of Erythrina suberosa (Roxb) bark

Ahmed Z, Aziz S, Alauddin S, Mohiuddin SG, Javed A, Ahmed R, et al.

J Pharm Bioallied Sci, 2020 04 10;12(2):210-216.
PMID: 32742121 DOI: 10.4103/jpbs.JPBS_223_19

Background: The study was focused on evaluating cytotoxic and antimicrobial activities of Erythrina suberosa (Roxb.) bark through in vitro pharmacological screening.
Materials and Methods: The bark was extracted using different solvents, for example, dichloromethane, ethyl acetate, methanol, and aqueous for obtaining the organic fractions. These organic fractions were then evaluated for their cytotoxic and antimicrobial activity compared with the standard. Cefixime was used as the standard for antibacterial assay, whereas clotrimazole was used as the standard for antifungal activities. Bacterial strains used were Staphylococcus aureus and methicillin-resistant S. aureus (MRSA), whereas for antifungal activities Candida albicans, Candida parapsilosis, and Candida krusei strains were used.
Results: The organic fractions obtained were evaluated for their cytotoxic and antimicrobial activities. In cytotoxic assay (Brine shrimp lethality assay), dichloromethane fraction was the most potent with LD50 of 47.63, whereas aqueous, methanol, and ethyl acetate fractions showed LD50 of 121.74, 422.2, and 201.96, respectively. Similarly, for antibacterial assay, dichloromethane fraction showed 32.2mm zone of inhibition against MRSA in comparison with standard cefixime (zone of inhibition, 30.5mm). A minimal zone of inhibition with crude saponins (13.1 and 12.2mm) was observed against C. albicans in comparison to standard (cefixime) with a zone of inhibition of 28.5mm. No prominent results were observed against C. parapsilosis and C. krusei strains.
Conclusion: The study was based on the plant from Indo-Pak origin, and it has shown some prominent cytotoxic and antibacterial activities. Although the results of this study have provided a basic idea about the efficacy of plant extract, still more explanatory and high-scale studies can be beneficial for elaborating the cytotoxic and antimicrobial activities of this plant.

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