Malaysian Agricultural Research and Development Institute MARDI
Malaysian Agricultural Research and Development Institute MARDI
Khalid K.,University of Malaya |
Khalid K.,Malaysian Agricultural Research and Development Institute MARDI |
Noh M.A.M.,University of Malaya |
Zain S.M.,University of Malaya |
Khan M.N.,University of Malaya
Topics in Current Chemistry | Year: 2017
The efficiency of counterion affinity towards ionic micelles is often described in terms of the degree of counterion binding (βX) to ionic micelles or the conventional ion-exchange constant (KXBr) or relative binding constant (RXBr) of X− and Br− counterions. This review describes the use of ionized phenyl salicylate ions, PSa−, as a new probe to determine KXBr values using a semiempirical spectrophotometric method. The value of KXBr is found to be comparable to reported values obtained using different probes by the semiempirical kinetic method as well as different physical methods. Application of semiempirical methods for calculation of KXBr or RXBr values involves an inherent assumption that these values are independent of the physicochemical characteristics of the probe molecule. © 2017, Springer International Publishing Switzerland.
Geesink G.,University of New England of Australia |
Sujang S.,Malaysian Agricultural Research and Development Institute MARDI |
Koohmaraie M.,King Saud University |
Koohmaraie M.,Forest Laboratories
Meat Science | Year: 2011
Lamb longissimus muscle (n= 6) sections were cooked at different times post mortem (prerigor, at rigor, 1. day. p.m., and 7. days. p.m.) using two cooking methods. Using a boiling waterbath, samples were either cooked to a core temperature of 70 °C or boiled for 3. h. The latter method was meant to reflect the traditional cooking method employed in countries where preparation of prerigor meat is practiced. The time postmortem at which the meat was prepared had a large effect on the tenderness (shear force) of the meat (P < 0.01). Cooking prerigor and at rigor meat to 70 °C resulted in higher shear force values than their post rigor counterparts at 1 and 7. days. p.m. (9.4 and 9.6 vs. 7.2 and 3.7. kg, respectively). The differences in tenderness between the treatment groups could be largely explained by a difference in contraction status of the meat after cooking and the effect of ageing on tenderness. Cooking pre and at rigor meat resulted in severe muscle contraction as evidenced by the differences in sarcomere length of the cooked samples. Mean sarcomere lengths in the pre and at rigor samples ranged from 1.05 to 1.20 μm. The mean sarcomere length in the post rigor samples was 1.44 μm. Cooking for 3. h at 100 °C did improve the tenderness of pre and at rigor prepared meat as compared to cooking to 70 °C, but not to the extent that ageing did. It is concluded that additional intervention methods are needed to improve the tenderness of prerigor cooked meat. © 2011 Elsevier B.V.
Sajab M.S.,National University of Malaysia |
Chia C.H.,National University of Malaysia |
Zakaria S.,National University of Malaysia |
Jani S.M.,Malaysian Agricultural Research and Development Institute MARDI |
And 4 more authors.
Bioresource Technology | Year: 2011
Chemically modified kenaf core fibres were prepared via esterification in the presence of citric acid (CA). The adsorption kinetics and isotherm studies were carried out under different conditions to examine the adsorption efficiency of CA-treated kenaf core fibres towards methylene blue (MB). The adsorption capacity of the kenaf core fibres increased significantly after the citric acid treatment. The values of the correlation coefficients indicated that the Langmuir isotherm fitted the experimental data better than the Freundlich isotherm. The maximum adsorption capacity of the CA-treated kenaf core fibres was found to be 131.6. mg/g at 60°C. Kinetic models, pseudo-first-order, pseudo-second-order and intraparticle diffusion, were employed to describe the adsorption mechanism. The kinetic data were found to fit pseudo-second-order model equation as compared to pseudo-first-order model. The adsorption of MB onto the CA-treated kenaf core fibres was spontaneous and endothermic. © 2011 Elsevier Ltd.
Yap H.-Y.Y.,University of Malaya |
Chooi Y.-H.,Australian National University |
Firdaus-Raih M.,National University of Malaysia |
Fung S.-Y.,University of Malaya |
And 3 more authors.
BMC Genomics | Year: 2014
Background: The sclerotium of Lignosus rhinocerotis (Cooke) Ryvarden or Tiger milk mushroom (Polyporales, Basidiomycota) is a valuable folk medicine for indigenous peoples in Southeast Asia. Despite the increasing interest in this ethnobotanical mushroom, very little is known about the molecular and genetic basis of its medicinal and nutraceutical properties.Results: The de novo assembled 34.3 Mb L. rhinocerotis genome encodes 10,742 putative genes with 84.30% of them having detectable sequence similarities to others available in public databases. Phylogenetic analysis revealed a close evolutionary relationship of L. rhinocerotis to Ganoderma lucidum, Dichomitus squalens, and Trametes versicolor in the core polyporoid clade. The L. rhinocerotis genome encodes a repertoire of enzymes engaged in carbohydrate and glycoconjugate metabolism, along with cytochrome P450s, putative bioactive proteins (lectins and fungal immunomodulatory proteins) and laccases. Other genes annotated include those encoding key enzymes for secondary metabolite biosynthesis, including those from polyketide, nonribosomal peptide, and triterpenoid pathways. Among them, the L. rhinocerotis genome is particularly enriched with sesquiterpenoid biosynthesis genes.Conclusions: The genome content of L. rhinocerotis provides insights into the genetic basis of its reported medicinal properties as well as serving as a platform to further characterize putative bioactive proteins and secondary metabolite pathway enzymes and as a reference for comparative genomics of polyporoid fungi. © 2014 Yap et al.; licensee BioMed Central Ltd.
Tan C.-S.,Malaysian Agricultural Research and Development Institute MARDI |
Ng S.-T.,LiGNO Biotech Sdn Bhd |
Tan J.,University of Malaya
Mycotaxon | Year: 2013
Lignosus cameronensis and L. tigris are described as new based on collections from the tropical forests of Pahang, Malaysia. Phenotypic and genotypic data support both as new species. Morphological features are illustrated, and the associated Internal Transcribed Region (ITS1 + 5.8S + ITS2) rDNA sequences have been deposited in the GenBank. Pore and basidiospore sizes are the main characters distinguishing these two Lignosus species from other members of the genus, with L. tigris distinguished from L. sacer by its larger pore size and smaller basidiospores and L. cameronensis separated from L. ekombitii by its smaller basidiospores. A key to the species of Lignosus is provided. © 2013. Mycotaxon, Ltd.
Sairi M.,Curtin University Australia |
Sairi M.,Malaysian Agricultural Research and Development Institute MARDI |
Arrigan D.W.M.,Curtin University Australia
Talanta | Year: 2014
The behaviour of protonated ractopamine (RacH+) at an array of micro-interfaces between two immiscible electrolyte solutions (micro-ITIES) was investigated via cyclic voltammetry (CV) and linear sweep stripping voltammetry (LSSV). The micro-ITIES array was formed at silicon membranes containing 30 pores of radius 11.09±0.12 μm and pore centre-to-centre separation of 18.4±2.1 times the pore radius. CV shows that RacH+ transferred across the water |1,6-dichlorohexane μITIES array at a very positive applied potential, close to the upper limit of the potential window. Nevertheless, CV was used in the estimation of some of the drug's thermodynamic parameters, such as the formal transfer potential and the Gibbs transfer energy. LSSV was implemented by pre-concentration of the drug, into the organic phase, followed by voltammetric detection, based on the back-transfer of RacH+ from the organic to aqueous phase. Under optimised pre-concentration and detection conditions, a limit of detection of 0.1 μM was achieved. In addition, the impact of substances such as sugar, ascorbic acid, metal ions, amino acid and urea on RacH+ detection was assessed. The detection of RacH+ in artificial serum indicated that the presence of serum protein interferes in the detection signal, so that sample deproteinisation is required for feasible bioanalytical applications. © 2014 Elsevier B.V.
Ng S.-K.,UCSI University |
Jessie L.-Y.L.,UCSI University |
Tan C.-P.,University Putra Malaysia |
Long K.,Malaysian Agricultural Research and Development Institute MARDI |
Nyam K.-L.,UCSI University
JAOCS, Journal of the American Oil Chemists' Society | Year: 2013
In order to improve the quality and protect against degradation, kenaf (Hibiscus cannabinus L.) seed oil was microencapsulated by using spray drying. The microencapsulated kenaf seed oil (MKSO) was then stored at 65 C for 24 days, the changes of fatty acids and bioactive compounds were examined every six days. Bulk (unencapsulated) kenaf seed oil was used as a control and was compared to the MKSO. The fatty acids and phytosterols compositions were determined by using gas chromatography, while tocopherols and phenolic acids of microencapsulated kenaf seed oil were determined by using high performance liquid chromatography. The results showed that there was a significant decrease (p < 0.05) in bioactive compounds in kenaf seed oil while the bioactive compounds in MKSO were maintained in a stable condition upon accelerated storage. Microencapsulation was shown to protect kenaf seed oil against oxidation, as well as preventing the degradation and/or loss of bioactive compounds in kenaf seed oil. © 2013 AOCS.
Nyam K.L.,University Putra Malaysia |
Tan C.P.,University Putra Malaysia |
Karim R.,University Putra Malaysia |
Lai O.M.,University Putra Malaysia |
And 2 more authors.
Food Chemistry | Year: 2010
Tocopherol-enriched oil was extracted by supercritical fluid extraction of carbon dioxide (SFE-CO2) from Kalahari melon and roselle seeds. The SFE-CO2 process was optimised using response surface methodology (RSM) with central composite design (CCD). Three SFE-CO2 parameters namely extracting pressure, extracting temperature, and flow rate of carbon dioxide were examined. The optimal SFE-CO2 conditions were determined and the quadratic response surfaces were drawn from the mathematical models. The optimal SFE-CO2 conditions for the extraction tocopherol-enriched oil from Kalahari melon seeds were: extracting pressure 290 bar, extracting temperature 58 °C, and flow rate of carbon dioxide 20 ml/min. The optimum conditions for roselle seeds were extracting pressure 200 bar, extracting temperature 80 °C, and flow rate of carbon dioxide 20 ml/min. These optimum conditions yielded tocopherol concentration of 274.74 and 89.75 mg/100 g oil from Kalahari seed and roselle seed, respectively. No significant (P > 0.05) differences were obtained between the experimental and predicted values. © 2009 Elsevier Ltd. All rights reserved.
Saad M.J.,Malaysian Agricultural Research and Development Institute MARDI
Journal of Sustainability Science and Management | Year: 2012
The manufacturing of kenaf core fibre - polypropylene composites with treated and non-treated maleated polypropylene (MAPP) was fabricated. Commercial MAPP (epolene 43) was used to determine MAPP's effectiveness as a coupling agent for kenaf fibre-composites. The mixturing between kenaf, PP and MAPP was done in an internal mixer machine to produce a pellet. A Kenaf core- polypropylene composite sample was manufactured using a compression moulding method on the kenaf and polypropylene (PP) pellets. The tensile, flexural and impact of the epolene 43 treated composite samples were better than those of the untreated composites. Scanning electron micrograph (SEM) proved that the interfacial region of treated composite board shows good interaction among kenaf's wood fibre and PP components. © Universiti Malaysia Terengganu Publisher.
Abdullah H.,Malaysian Agricultural Research and Development Institute MARDI
Acta Horticulturae | Year: 2011
The quality of fresh fruits is a combination of characteristics, attributes and properties that give the commodity value for food. Quality is used in various ways to indicate degree of excellence. For pineapple, quality is always associated with excellent appearance, freshness, taste, colour and aroma, besides being free from injuries and disorders. Effective postharvest handling should begin with excellent quality fruits at harvest and continues with proper control measures along the handling chain until consumption. Pineapple for long distance markets should be able to withstand long distance transportation and still remain in excellent condition after reaching the destination. Effective maintenance of quality in pineapple incorporates good handling practices including the use of cold chain, proper grading, suitable packaging and the right treatments.