Displaying publications 1 - 20 of 21 in total

  1. Rashidah, S., Jinap, S., Nazamid, S., Jamilah, B.
    This study was carried out to extract and compare the characteristic ability of globulins from cottonseed, alfalfa seed, pea seed, mung bean and French bean with cocoa seeds to produce cocoa-specific aroma precursors. The extracted globulins were compared through SDS PAGE, amino acid and oligopeptide profiles. A very low recovery was obtained during globulin extraction from different seeds ranging from 0.5% to 2.7%. Cottonseed produced the highest total protein (13.90 mg/g), followed by cocoa seed (11.91 mg/g), whereas alfalfa seed, mung bean, pea seed and French bean produced 7.86, 4.77, 4.59 and 3.89 mg/g respectively. Two distinctive bands of 51.1 and 33.0 kDa were observed for cocoa vicilin-class globulin (VCG) from SDS PAGE. More than three bands were shown for other seed globulins. Comparative HPLC analyses of the obtained peptide mixtures revealed different and complex patterns of predominantly hydrophobic peptides. A similar high content of amides (glutamic acids-glutamine, aspartic acid- asparagine and arginine) and low concentrations of lysine were observed in all seeds globulin.
  2. Nafi’, A., Foo, H.L., Jamilah, B., Ghazali. H.M.
    Proteases in ginger rhizome have the potentials in industrial applications. This study was conducted to extract and characterize the proteolytic enzyme from ginger (Zingiber officinale Roscoe). Ginger protease (GP) was extracted from ginger rhizome by homogenization with 100 mM potassium phosphate buffer pH 7.0 containing 10 mM cysteine and 5 mM EDTA which were found to be the most efficient extraction buffer and stabilizers. After centrifugation at 10,500 x g, protein in the crude extract was precipitated using 60% ammonium sulfate following which the precipitate was redissolved in 50 mM potassium phosphate buffer pH 7.0, dialyzed and then lyophilized. The extraction method yielded 0.94% (w/w of fresh weight) of GP with a specific activity of 27.6 ± 0.1 Unit/mg protein where 1 Unit is defined as the amount of protease causing an increase in absorbance by 1 unit per minute using azocasein as the substrate. Results show that the GP was completely inhibited by heavy metal cations i.e. Cu2+and Hg2+, and a thiol blocking agent or inhibitor, n-ethyl maleimide (NEM), indicating that GP is most probably a cysteine protease. The enzyme has an optimum temperature at 60⁰C and the optimum pH ranged between pH 6 to 8. Monovalent cations (K+ and Na+) have no significant effect on activity of GP, but divalent and trivalent cations showed moderate inhibitory effect. Detergents such as sodium dodecyl sulfate increased the activity of GP while Tween 80 and Tween 20 slightly reduced the activity.
  3. Nura, M., Kharidah, M., Jamilah, B., Roselina, K.
    This study examined the physicochemical properties of rice flours with five different particle sizes (≤63, 80, 100, 125, and 140 μm) prepared by dry milling and their effects on textural properties of laksa noodles. Rice flour with the smallest particle size had the highest water absorption index, peak viscosity, hot paste viscosity, breakdown, final or cold paste viscosity and gel hardness, but the lowest gelatinization temperature. Reduction of rice flour particle size improved textural properties of laksa noodle. Laksa noodle produced from rice flour with the smallest particle size had the best textural properties.
  4. Ali, G., Russly, A.R., Jamilah, B., Azizah, O., Mandana, B.
    This study aims to evaluate the effect of heat and the simultaneous application of heat (80-95°C) and ultrasonic waves (thermosonication) on the inactivation kinetic of peroxidase and vitamin C degradation in seedless guava. Ultrasonic wave’s amplitudes except 25 and 100% had significant (P 0.98). In the heat blanching process, the peroxidase inactivation rate constant increased from 1.1×10-2 to 4.6×10-2 s-1. However, the inactivation rate of peroxidase was increased by 1.5–3 times in the temperature range 80–95ºC, with the 50 and 75% ultrasonic wave amplitudes, respectively. Decreases in vitamin C contents due to blanching treatments were found. Blanching processes at high temperature and short time resulted in higher vitamin C retention. It was found that thermosonication treatment inactivates seedless guava peroxidase at less severe blanching conditions and consequently retains vitamin C content at higher levels. The present findings will help to design the blanching conditions in order to reduce the severity of conventional thermal treatments and, therefore, improving the quality of the thermally treated product.
  5. Jamilah, B., Abdulkadir Gedi, M., Suhaila, M., Md.Zaidul, I.S.
    The extraction of phenolics from Citrus hystrix leaf was carried out using supercritical fluid extraction and was optimized using response surface methodology (RSM). The effects of CO2 flow rate, extraction pressure and extraction temperature on yield, total phenolic content and diphenyl-picrylhydrazyl-IC50 were evaluated and compared with ethanol extraction. The extraction pressure was the most significant factor affecting the yield, TPC and DPPH-IC50 of the extracts, followed by CO2 flow rate and the extraction temperature. The optimum conditions of pressure, CO2 flow rate and temperature were at 267 bars, 18 g/min and 50°C, respectively. The yield, TPC and DPPH-IC50 obtained were 5.06%, 116.53 mg GAE/g extract and IC50 of 0.063 mg/ml, respectively. These values were not significantly different (p
  6. Nor-Khaizura, M.A.R., Zaiton, H, Jamilah, B., Gulam Rusul, R.A.
    Keropok lekor is an important fish product in Malaysia. The customer demands for keropok lekorhave been increasing. This study was conducted to analyze the microbiological quality of keropok lekor in every stage of its processing, namely mincing, mixing, kneading, boiling and cooling. When processing keropok lekor, the boiling of keropok lekor at 100°C for 10 min reduced the Total Plate Counts (4.38±0.47 log10 cfu/g), psychrotrophic counts (2.00 ± 0.00 log10 cfu/g), mesophilic sporeformer counts (1.26 ± 0.34 log10 cfu/g) and total coliform counts (1.71±0.51 log Most Probable Number/g) significantly (p>0.05). However, the microbial counts were found to increase significantly (p
  7. Yazdan. M,, Jamilah, B., Yaakob C.M., Sharifah, K.
    Effects of breading materials and deep-fat frying on fat uptake, moisture content and fatty acid composition of the black pomfret (Parastromateus niger) fillets. Black pomfret fillets both breaded and non-breaded were deep-fat fried in sunflower oil and palm olein. Fat uptake, moisture content and fatty acid composition in the fillets were determined. Total fat content in the fillets of both breaded and un-breaded fillets increased significantly (p
  8. Muhamad, S.A.S., Jamilah, B., Russly, A.R., Faridah, A.
    Ten solvents were used to extract phytochemicals from the peel of Carica papaya cv. Sekaki/
    Hong Kong to evaluate antibacterial activities and determine chemical composition of Carica
    papaya cv. Sekaki/Hong Kong seeds. The antibacterial activities of ten solvent extracts were
    tested against 14 microorganisms vis Shigella sonnei, Salmonella typhimurium, Escherichia
    coli, Salmonella enteritidis, Vibrio vulnificus, Vibrio parahaemolyticus, Proteus mirabilis,
    Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes, Corynebacterium diphtheria,
    Clostridium perfringens, Streptococcus pneumoniae and Bacillus subtilis using disk diffusion
    test (DDT). The Carica papaya seed of ACN and MeOH extracts inhibited 11 microorganisms,
    indicating their broad spectrum activity. The disk diffusion test exhibited moderate and clear
    inhibition on C. diphtheria, S. pneumonia, B. subtilis and C. perfringens. MeOH extract
    inhibited S. enteritidis, V. vulnificus, P. mirabilis and B. cereus with the lowest MIC at 11.25
    mg/mL each, thus was chosen as the best extract. The hierarchy of extract potency can be
    ranked as MeOH > acetone > ACN > CHCL3 > hexane > DE = PE > EtOH > DCM based
    on clear and moderate inhibition and the lowest MIC. TPC and TFC of the extracts ranged
    between 4.83 to 22.59 mg GAE/g DW and 1.32 (water) and 17.15 mg QE/g DW respectively.
    The GC/MS analysis of MeOH extract identified potential antibacterial compounds such as
    isothiocyanatomethyl benzene, 9-octadecenoic acid, hexadecanoic acid and β-sitosterol. The
    Carica papaya seed cv. Sekaki/ Hong Kong possessed significant antibacterial activities when
    extracted by different solvents in particular MeOH solvent.
  9. Zad Bagher Seighalani, F., Jamilah, B., Saari, N.
    Physico-chemical properties of red tilapia mince during the preparation of surimi and kamaboko
    gel were evaluated to determine the potential of red tilapia as a source for surimi. Processing
    of red tilapia for surimi and kamaboko gel resulted in a significant lower Ca2+ ATPase activity,
    protein and fat than mincemeat. Thermograms of Differential Scanning Calorimetry (DSC)
    showed three peaks at 31.0, 54.5 and 72.0°C for the mince and only two peaks for surimi and
    kamaboko gel respectively. Enthalpies of myosin peaks in surimi and kamaboko gel were lower
    compared to the mincemeat, but there were no significant differences among the enthalpies
    (ΔH) of their actin peaks. The highest maximum storage modulus (G’max) was obtained at
    78.5°C for kamaboko gel which corresponded to 2420 Pa. The sodium dodecyl sulfate (SDSPAGE)
    gel showed apparent intensity different in myosin (205 kDa) and no obvious differences
    for actin (43 kDa).
  10. Jamilah, B., Umi Hartina, M.R., Mat Hashim, D., Sazili, A.Q.
    The properties of collagens from Barramundi (Lates calcarifer) skin obtained by acid solubilized (control), pepsin and papain aided extractions were investigated. The yields of collagens (dry weight basis) for acid solubilized, pepsin and papain aided extractions were 8.1, 43.6 and 44.0%, respectively. The collagens were generally colorless although collagens from the enzymes aided-extractions were slightly darker. Based on the e-nose evaluation, the collagens were considered odorless. The pH of all the collagens was in the vicinity of 3; however, those extracted with papain had significantly higher pH. The polypeptide profiles obtained in the SDS-PAGE analysis for pepsin extracted collagen were similar to those of acid solubilized collagens. Papain extracted collagen had distinctly different SDS-PAGE pattern. All the extracted collagens were of type 1 with apparent peptides molecular weight distribution of 37 to 250 kDalton. They had high solubility in pH 2 to 5 and increasing NaCl concentration up to 6%.
  11. Jamilah, B., Shu, C. E., Kharidah, M., Dzulkifly, M. A., Noranizan, A.
    Pitaya peel (Hylocereus polyrhizus), which consists approximately 22% of the whole fruit weight, is discarded during processing. Physico-chemical properties of the discarded pitaya peel were determined in
    order to evaluate its potential for recovery of any value-added materials. The moisture content of the peel was approximately 92.7% and it was low in total soluble solids, protein, ash and fat content. Betacyanin pigment (150.46 ± 2.19 mg/100 g) and pectin (10.8%) were high in the peel. Glucose, maltose and fructose were detected in the peel but not sucrose and galactose. The peel also had very high insoluble and soluble dietary fibre which had exhibited a good ratio of insoluble dietary fibre to soluble dietary fibre (3.8: 1.0).
  12. Chong, C.Y., Fatimah, A.B., Russly, A.R., Jamilah, B., Selvi, V., Maryam, S.
    The profile of total volatile base nitrogen (TVBN), pH, biogenic amines were studied in Indian mackerel packed under different levels of CO2. Gutted and beheaded Indian mackerel was stored in air, vacuum packaging (VP), 30% CO2/65% N2/5% O2 (M30C), 60% CO2/35%N2/5%O2 (M60C), 80% CO2/15%N2/5% O2 (M80C) and 100% CO2 (M100C) at 5°C for 12 days. The application of VP and MAP was effective in retarding the formation of TVBN, total biogenic amines and improve the shelf life of Indian mackerel. Cadaverine obtained the best correlation with storage time when compared with other biogenic amines. Cadaverine or cadaverine + putrescine can serve as a reliable objective freshness indicator of fish stored in different atmospheres. Among the commonly used freshness indices, TVBN was the best quality indicator correlated with histamine. VP and MAP conditions influenced the performance of quality indicators. pH was a good quality indicator of spoilage in air-stored fish except for VP and MAP packed fish. Lower value of TVBN (30 mg/100g) was suggested as an upper limit for this species of fish under MAP condition based on APC and sensory result.
  13. Chong, C.Y., Abu Bakar, F., Russly, A.R., Jamilah, B., Mahyudin, N.A.
    Biological amines are nitrogenous compounds that occur naturally in wide variety of food. Histamine, putrescine, cadavarine, tyramine, spermine, spermidine, tryptamine and β-phenylethylamine are the biogenic amines that are normally present in foods. Although the biogenic amines play some important physiological functions but high level of amines can cause toxicological effects. High amount of amines can be produced by bacteria during amino acids decarboxylation and have been identified as one of the important agent causing seafood intoxication. Temperature is the major factor for controlling the biogenic amines formation in food. The effects of other alternatives are also discussed including salting, packaging, irradiation, high pressure processing and the use of starter culture. A variety of techniques can be combined together to control the microbial growth and enzyme activity during processing and storage for better shelf life extension and food safety.
  14. Muhamad, S. A. S., Jamilah, B., Russly, A. R., Faridah, A.
    Ten solvents were used to extract phytochemicals from the peel of Carica papaya cv.
    Sekaki/Hong Kong to determine their antibacterial activities. Moderate to clear inhibition on
    Corynebacterium diphtheriae, Streptococcus pneumoniae, Bacillus subtilis and Clostridium
    perfringens were obtained from the disk diffusion test out of fourteen pathogens tested.
    Petroleum ether extract, the most potent extract, showed moderate inhibition towards C.
    diphtheriae and S. pneumoniae at MIC of 5.63 mg/mL and 1.40 mg/mL. Polar solvents
    gave higher yield, total phenolic and total flavonoid contents than nonpolar solvents. Extract
    yields were 10.9 to 84.1 mg/g in polar solvents and 3.9 to 20.3 mg/g in non-polar solvents.
    Twenty eight compounds were identified in petroleum extracts through GC/MS analysis.
    Among the compounds identified were fatty acids, esters, alkane, tocopherols and sterols.
    9,12,15-octadecatrienoic acid was the most abundant compound.
  15. Rodiah, M. H., Jamilah, B., Sharifah Kharidah, S. M., Russly, A. R.
    The physico-chemical and antioxidant activity of the mesocarp and exocarp of Borassus flabellifer were determined to assess the potential of the fruit as a food ingredient. Proximate analysis indicated that both mesocarp and exocarp had a high fibre content of 23.92% and 28.20%, respectively, of which 62.5% and 79.4% were insoluble dietary fibre. The soluble dietary fibre was < 0.50% for both samples. Hemicellulose was the major component in the exocarp followed by cellulose and lignin. Meanwhile for the mesocarp, cellulose was the highest component followed by hemicellulose and lignin. Fructose, galactose, glucose, mannose and sucrose were detected in both samples. Phenol and tannins were present in both mesocarp and exocarp; however, saponin was only detected in the mesocarp. Radical scavenging activity (157.05 mM TE/g) and reducing power (213.05 mM Fe2+) of the exocarp were significantly higher as compared to those of the mesocarp.
  16. Azilawati MI, Hashim DM, Jamilah B, Amin I
    Food Chem, 2015 Apr 1;172:368-76.
    PMID: 25442566 DOI: 10.1016/j.foodchem.2014.09.093
    The amino acid compositions of bovine, porcine and fish gelatin were determined by amino acid analysis using 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate as derivatization reagent. Sixteen amino acids were identified with similar spectral chromatograms. Data pre-treatment via centering and transformation of data by normalization were performed to provide data that are more suitable for analysis and easier to be interpreted. Principal component analysis (PCA) transformed the original data matrix into a number of principal components (PCs). Three principal components (PCs) described 96.5% of the total variance, and 2 PCs (91%) explained the highest variances. The PCA model demonstrated the relationships among amino acids in the correlation loadings plot to the group of gelatins in the scores plot. Fish gelatin was correlated to threonine, serine and methionine on the positive side of PC1; bovine gelatin was correlated to the non-polar side chains amino acids that were proline, hydroxyproline, leucine, isoleucine and valine on the negative side of PC1 and porcine gelatin was correlated to the polar side chains amino acids that were aspartate, glutamic acid, lysine and tyrosine on the negative side of PC2. Verification on the database using 12 samples from commercial products gelatin-based had confirmed the grouping patterns and the variables correlations. Therefore, this quantitative method is very useful as a screening method to determine gelatin from various sources.
  17. Azilawati MI, Hashim DM, Jamilah B, Amin I
    J Chromatogr A, 2014 Aug 1;1353:49-56.
    PMID: 24797394 DOI: 10.1016/j.chroma.2014.04.050
    In-house method validation was conducted to determine amino acid composition in gelatin by a pre-column derivatization procedure with the 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate reagent. The analytical parameters revealed that the validated method was capable of selectively performing a good chromatographic separation for 18 amino acids in less than 40 min; the overall detection and quantitation limit for amino acids fell into ranges of 5.68-12.48 and 36.0-39.0 pmol/μl, respectively; the matrix effect was not observed, and the linearity range was 37.5-1000 pmol/μl. The accuracy (precision and recovery) analyses of the method were conducted under repeatable conditions on different days in random order. Method precision revealed by HorRat values was significantly less than 2, except for histidine with a precision of 2.19, and the method recoveries had a range of 80-115% except for alanine which was recovered at 79.4%. The findings were reproducible and accurately defined, and the method was found to be suited to routine analysis of amino acid composition in gelatin-based ingredients.
  18. Zakiah I, Zaini AR, Jamilah B, Zawiah A
    Malays J Pathol, 1992 Dec;14(2):91-4.
    PMID: 1304630
    Over a three-year-period, 310 babies with prolonged jaundice admitted to GHKL were studied, to determine the incidence of alpha-1-antitrypsin deficiency as a cause of the problem. Ninety-two babies (29.7%) were found to be alpha-1-antitrypsin deficient. The percentage incidence was found to be highest in Indians (33.3%), followed by Malays (31.9%) and Chinese (26.7%). There was a male preponderance with a M:F ratio of 1.6:1. Most of these babies presented at the hospital at the age of more than two weeks but less than one month. Apart from the problem of prolonged jaundice and alpha-1-antitrypsin deficiency, 2 had associated bleeding problems, 11 associated infections and 3 respiratory problems. Two babies had clinical features of Down's syndrome, 2 had G6PD deficiency and 1 had congenital hypothyroidism. AST, ALT and ALPO4 were high in 20, 26 and 3 babies respectively.
  19. Azilawati MI, Dzulkifly MH, Jamilah B, Shuhaimi M, Amin I
    J Pharm Biomed Anal, 2016 Sep 10;129:389-397.
    PMID: 27454091 DOI: 10.1016/j.jpba.2016.07.012
    A detailed procedure for estimating uncertainty according to the Laboratory of Government Chemists/Valid Analytical Measurement (LGC/VAM) protocol for determination of 18 amino acids in gelatin is proposed. The expanded uncertainty was estimated using mainly the method validation data (precision and trueness). Other sources of uncertainties were contributed by components in standard preparation measurements. The method scope covered a single matrix (gelatin) under a wide range of analyte concentrations. The uncertainty of method precision, μ(P) was 0.0237-0.1128pmolμl(-1) in which hydroxyproline and histidine represented the lowest and highest values of uncertainties, respectively. Proline and phenylalanine represented the lowest and highest uncertainties value for method recovery, μ(R) that was estimated within 0.0064-0.0995pmolμl(-1). The uncertainties from other sources, μ(Std) were 0.0325, 0.0428 and 0.0413pmolμl(-1) that were contributed by hydroxyproline, other amino acids and cystine, respectively. Hydroxyproline and phenylalanine represented the lowest and highest values of expanded uncertainty, U(y) that were determined at 0.0949 and 0.2473pmolμl(-1), respectively. The data were accurately defined and fulfill the technical requirements of ISO 17025:2005.
  20. Khong NM, Yusoff FM, Jamilah B, Basri M, Maznah I, Chan KW, et al.
    Food Chem, 2016 Apr 1;196:953-60.
    PMID: 26593577 DOI: 10.1016/j.foodchem.2015.09.094
    The study aimed to evaluate nutraceutical potential of three commercially significant edible jellyfish species (Acromitus hardenbergi, Rhopilema hispidum and Rhopilema esculentum). The bell and oral arms of these jellyfishes were analyzed for their proximate composition, calorific value, collagen content, amino acid profile, chemical score and elemental constituent. In general, all jellyfish possessed low calorific values (1.0-4.9 kcal/g D.W.) and negligible fat contents (0.4-1.8 g/100 g D.W.), while protein (20.0-53.9 g/100 g D.W.) and minerals (15.9-57.2g/100g D.W.) were found to be the richest components. Total collagen content of edible jellyfish varied from 122.64 to 693.92 mg/g D.W., accounting for approximately half its total protein content. The dominant amino acids in both bell and oral arms of all jellyfish studied includes glycine, glutamate, threonine, proline, aspartate and arginine, while the major elements were sodium, potassium, chlorine, magnesium, sulfur, zinc and silicon. Among the jellyfish, A. hardenbergi exhibited significantly higher total amino acids, chemical scores and collagen content (p<0.05) compared to R. hispidum and R. esculentum. Having good protein quality and low calories, edible jellyfish is an appealing source of nutritive ingredients for the development of oral formulations, nutricosmetics and functional food.
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