Displaying publications 1 - 20 of 31 in total

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  1. Fulltext Solid-state fermentation of oil palm frond petiole for lignin peroxidase and xylanase-rich cocktail production
    Mohamad Ikubar MR, Abdul Manan M, Md Salleh M, Yahya A
    3 Biotech, 2018 May;8(5):259.
    PMID: 29765817 DOI: 10.1007/s13205-018-1268-1
    In current practice, oil palm frond leaflets and stems are re-used for soil nutrient recycling, while the petioles are typically burned. Frond petioles have high commercialization value, attributed to high lignocellulose fiber content and abundant of juice containing free reducing sugars. Pressed petiole fiber is the subject of interest in this study for the production of lignocellulolytic enzyme. The initial characterization showed the combination of 0.125 mm frond particle size and 60% moisture content provided a surface area of 42.3 m2/g, porosity of 12.8%, and density of 1.2 g/cm3, which facilitated fungal solid-state fermentation. Among the several species of Aspergillus and Trichoderma tested, Aspergillus awamori MMS4 yielded the highest xylanase (109 IU/g) and cellulase (12 IU/g), while Trichoderma virens UKM1 yielded the highest lignin peroxidase (222 IU/g). Crude enzyme cocktail also contained various sugar residues, mainly glucose and xylose (0.1-0.4 g/L), from the hydrolysis of cellulose and hemicellulose. FT-IR analysis of the fermented petioles observed reduction in cellulose crystallinity (I900/1098), cellulose-lignin (I900/1511), and lignin-hemicellulose (I1511/1738) linkages. The study demonstrated successful bioconversion of chemically untreated frond petioles into lignin peroxidase and xylanase-rich enzyme cocktail under SSF condition.
    Matched MeSH terms: Xylose
  2. Fulltext Evaluation of the effect of soluble polysaccharides of palm kernel cake as a potential prebiotic on the growth of probiotics
    Bello B, Mustafa S, Tan JS, Ibrahim TAT, Tam YJ, Ariff AB, et al.
    3 Biotech, 2018 Aug;8(8):346.
    PMID: 30073131 DOI: 10.1007/s13205-018-1362-4
    This paper deliberates the extraction, characterization and examination of potential application of soluble polysaccharides of palm kernel cake (PKC) as a prebiotic. The PKC was defatted and crude polysaccharide was obtained through water, citric acid or NaOH extraction. The physiochemical properties of the extracted polysaccharides viz. total carbohydrates, protein content, solubility rate, monosaccharides composition, structural information and thermal properties were also determined. The extracted soluble polysaccharides were further subjected to a digestibility test using artificial human gastric juice. Finally, their prebiotic potential on two probiotics, namely Lactobacillus plantarum ATCC 8014 and Lb. rhamnosus ATCC 53103 were evaluated in vitro. It was observed that PKC contained ash (5.2%), moisture (7.4%), carbohydrates (65.8%), protein (16.5%) and fat (5.1%). There were significant differences (P  95%). Protein content in SCPW, SCPCA and SCPN are 0.72, 0.40 and 0.58, respectively, and the peaks which indicated the presence of protein were observed at approximately 1640 cm-1 (amide I). FTIR spectroscopy revealed that the polysaccharides extracts were linked to β and α-glycosidic bonds and thermal analysis using differential scanning calorimeter (DSC) showed the main degradation temperature of SP is about 121 to 125 °C. The SP were found to be highly resistance (> 96%) to hydrolysis when subjected to artificial human gastric juice. The prebiotics potentials of the polysaccharides on probiotics in vitro demonstrated an increase in proliferation of Lb. plantarum ATCC 8014 and Lb. rhamnosus ATCC 53103 with decrease in the pH of the medium and producing organic acids.All the above findings strongly indicated that polysaccharides extracted from PKC, an industrial waste, have a potential to be exploited as novel prebiotics.
    Matched MeSH terms: Xylose
  3. Production of xylose from Meranti wood sawdust by dilute acid hydrolysis
    Rafiqul IS, Sakinah AM, Karim MR
    Appl Biochem Biotechnol, 2014 Sep;174(2):542-55.
    PMID: 25082763 DOI: 10.1007/s12010-014-1059-z
    Xylitol production by bioconversion of xylose can be economically interesting if the raw material can be recovered from a cheap lignocellulosic biomass (LCB). Meranti wood sawdust (MWS) is a renewable and low-cost LCB that can be used as a promising and economic source of xylose, a starting raw material for the manufacture of several specialty chemicals, especially xylitol. This study aimed to optimize the hydrolysis process of MWS and to determine the influence of temperature, H2SO4 concentration, and residence time on xylose release and on by-product formation (glucose, arabinose, acetic acid, furfural, hydroxymethylfurfural (HMF), and lignin degradation products (LDPs)). Batch hydrolysis was conducted under various operating conditions, and response surface methodology was adopted to achieve the highest xylose yield. Xylose production was highly affected by temperature, acid concentration, and residence time. The optimum temperature, acid concentration, and time were determined to be 124 °C, 3.26 %, and 80 min, respectively. Under these optimum conditions, xylose yield and selectivity were attained at 90.6 % and 4.05 g/g, respectively.
    Matched MeSH terms: Xylose/biosynthesis*
  4. Enhanced xylose recovery from oil palm empty fruit bunch by efficient acid hydrolysis
    Tan HT, Dykes GA, Wu TY, Siow LF
    Appl Biochem Biotechnol, 2013 Aug;170(7):1602-13.
    PMID: 23709290 DOI: 10.1007/s12010-013-0298-8
    Oil palm empty fruit bunch (EFB) is abundantly available in Malaysia and it is a potential source of xylose for the production of high-value added products. This study aimed to optimize the hydrolysis of EFB using dilute sulfuric acid (H2SO4) and phosphoric acid (H3PO4) via response surface methodology for maximum xylose recovery. Hydrolysis was carried out in an autoclave. An optimum xylose yield of 91.2 % was obtained at 116 °C using 2.0 % (v/v) H2SO4, a solid/liquid ratio of 1:5 and a hydrolysis time of 20 min. A lower optimum xylose yield of 24.0 % was observed for dilute H3PO4 hydrolysis at 116 °C using 2.4 % (v/v) H3PO4, a solid/liquid ratio of 1:5 and a hydrolysis time of 20 min. The optimized hydrolysis conditions suggested that EFB hydrolysis by H2SO4 resulted in a higher xylose yield at a lower acid concentration as compared to H3PO4.
    Matched MeSH terms: Xylose/chemical synthesis*
  5. Enzymatic Production of Bioxylitol from Sawdust Hydrolysate: Screening of Process Parameters
    Rafiqul IS, Sakinah AM, Zularisam AW
    Appl Biochem Biotechnol, 2015 Jun;176(4):1071-83.
    PMID: 25904039 DOI: 10.1007/s12010-015-1630-2
    Xylose-rich sawdust hydrolysate can be an economic substrate for the enzymatic production of xylitol, a specialty product. It is important to identify the process factors influencing xylitol production. This research aimed to screen the parameters significantly affecting bioxylitol synthesis from wood sawdust by xylose reductase (XR). Enzymatic bioxylitol production was conducted to estimate the effect of different variables reaction time (2-18 h), temperature (20-70 °C), pH (4.0-9.0), NADPH (1.17-5.32 g/L), and enzyme concentration (2-6 %) on the yield of xylitol. Fractional factorial design was followed to identify the key process factors. The screening design identified that time, temperature, and pH are the most significant factors influencing bioxylitol production among the variables with the values of 12 h, 35 °C, and 7.0, respectively. These conditions led to a xylitol yield of 71 % (w/w). This is the first report on the statistical screening of process variables influencing enzyme-based bioxylitol production from lignocellulosic biomass.
    Matched MeSH terms: Xylose/chemistry*
  6. Hydrothermal and wet disk milling pretreatment for high conversion of biosugars from oil palm mesocarp fiber
    Zakaria MR, Norrrahim MN, Hirata S, Hassan MA
    Bioresour Technol, 2015 Apr;181:263-9.
    PMID: 25659104 DOI: 10.1016/j.biortech.2015.01.072
    Eco-friendly pretreatment methods for lignocellulosic biomass are being developed as alternatives to chemical based methods. Superheated steam (SHS), hot compressed water (HCW) and wet disk milling (WDM) were used individually and with combination to partially remove hemicellulose and alter the lignin composition of recalcitrant structure of oil palm mesocarp fiber (OPMF). The efficiency of the pretreatment methods was evaluated based on the chemical compositions altered, SEM analysis, power consumption and degree of enzymatic digestibility. Hemicellulose removal (94.8%) was more pronounced under HCW compared to SHS, due to maximal contact of water and production of acetic acid which enhanced further degradation of hemicellulose. Subsequent treatment with WDM resulted in defibrillation of OPMF and expansion of the specific surface area thus increasing the conversion of cellulose to glucose. The highest glucose yield was 98.1% (g/g-substrate) when pretreated with HCW (200 °C, 20 min) and WDM which only consumed 9.6 MJ/kg of OPMF.
    Matched MeSH terms: Xylose/analysis
  7. Combined pretreatment using alkaline hydrothermal and ball milling to enhance enzymatic hydrolysis of oil palm mesocarp fiber
    Zakaria MR, Hirata S, Hassan MA
    Bioresour Technol, 2014 Oct;169:236-43.
    PMID: 25058299 DOI: 10.1016/j.biortech.2014.06.095
    Hydrothermal pretreatment of oil palm mesocarp fiber was conducted in tube reactor at treatment severity ranges of log Ro = 3.66-4.83 and partial removal of hemicellulose with migration of lignin was obtained. Concerning maximal recovery of glucose and xylose, 1.5% NaOH was impregnated in the system and subsequent ball milling treatment was employed to improve the conversion yield. The effects of combined hydrothermal and ball milling pretreatments were evaluated by chemical composition changes by using FT-IR, WAXD and morphological alterations by SEM. The successful of pretreatments were assessed by the degree of enzymatic digestibility of treated samples. The highest xylose and glucose yields obtained were 63.2% and 97.3% respectively at cellulase loadings of 10 FPU/g-substrate which is the highest conversion from OPMF ever reported.
    Matched MeSH terms: Xylose/analysis
  8. Effect of autohydrolysis and enzymatic treatment on oil palm (Elaeis guineensis Jacq.) frond fibres for xylose and xylooligosaccharides production
    Sabiha-Hanim S, Noor MA, Rosma A
    Bioresour Technol, 2011 Jan;102(2):1234-9.
    PMID: 20797853 DOI: 10.1016/j.biortech.2010.08.017
    Oil palm (Elaeis guineensis Jacq.) is one of the most important commercial crops for the production of palm oil, which generates 10.88 tons of oil palm fronds per hectare of plantation as a by-product. In this study, oil palm frond fibres were subjected to an autohydrolysis treatment using an autoclave, operated at 121 °C for 20-80 min, to facilitate the separation of hemicelluloses. The hemicellulose-rich solution (autohydrolysate) was subjected to further hydrolysis with 4-16 U of mixed Trichoderma viride endo-(1,4)-β-xylanases (EC 3.2.1.8) per 100 mg of autohydrolysate. Autoclaving of palm fronds at 121°C for 60 min (a severity factor of 2.40) recovered 75% of the solid residue, containing 57.9% cellulose and 18% Klason lignin, and an autohydrolysate containing 14.94% hemicellulose, with a fractionation efficiency of 49.20%. Subsequent enzymatic hydrolysis of the autohydrolysate with 8 U of endoxylanase at 40 °C for 24 h produced a solution containing 17.5% xylooligosaccharides and 25.6% xylose. The results clearly indicate the potential utilization of oil palm frond, an abundantly available lignocellulosic biomass for the production of xylose and xylooligosaccharides which can serve as functional food ingredients.
    Matched MeSH terms: Xylose/biosynthesis*
  9. Hot compressed water pretreatment of oil palm fronds to enhance glucose recovery for production of second generation bio-ethanol
    Goh CS, Lee KT, Bhatia S
    Bioresour Technol, 2010 Oct;101(19):7362-7.
    PMID: 20471249 DOI: 10.1016/j.biortech.2010.04.048
    This work presents the pretreatment of oil palm fronds (OPF) using hot compressed water (HCW) to enhance sugar recovery in enzymatic hydrolysis. A central, composite rotatable design was used to optimize the effect of reaction temperature, reaction time and liquid-solid ratio on the pretreatment process. All variables were found to significantly affect the glucose yield. A quadratic polynomial equation was used to model glucose yield by multiple regression analysis, using response surface methodology (RSM). Using a 10 bar pressurized reactor, the optimum conditions for pretreatment of OPF were found at 178 degrees C, 11.1 min and a liquid-solid ratio of 9.6. The predicted glucose yield was 92.78 wt.% at the optimum conditions. Experimental verification of the optimum conditions gave a glucose yield in good agreement with the estimated value of the model.
    Matched MeSH terms: Xylose/analysis
  10. Optimization studies on acid hydrolysis of oil palm empty fruit bunch fiber for production of xylose
    Rahman SH, Choudhury JP, Ahmad AL, Kamaruddin AH
    Bioresour Technol, 2007 Feb;98(3):554-9.
    PMID: 16647852
    Oil palm empty fruit bunch fiber is a lignocellulosic waste from palm oil mills. It is a potential source of xylose which can be used as a raw material for production of xylitol, a high value product. The increasing interest on use of lignocellulosic waste for bioconversion to fuels and chemicals is justifiable as these materials are low cost, renewable and widespread sources of sugars. The objective of the present study was to determine the effect of H(2)SO(4) concentration, reaction temperature and reaction time for production of xylose. Batch reactions were carried out under various reaction temperature, reaction time and acid concentrations and Response Surface Methodology (RSM) was followed to optimize the hydrolysis process in order to obtain high xylose yield. The optimum reaction temperature, reaction time and acid concentration found were 119 degrees C, 60 min and 2%, respectively. Under these conditions xylose yield and selectivity were found to be 91.27% and 17.97 g/g, respectively.
    Matched MeSH terms: Xylose/chemistry*
  11. Fractionation of oil palm empty fruit bunch by bisulfite pretreatment for the production of bioethanol and high value products
    Tan L, Wang M, Li X, Li H, Zhao J, Qu Y, et al.
    Bioresour Technol, 2016 Jan;200:572-8.
    PMID: 26539970 DOI: 10.1016/j.biortech.2015.10.079
    In this work, fractionation of empty fruit bunch (EFB) by bisulfite pretreatment was studied for the production of bioethanol and high value products to achieve biorefinery of EFB. EFB was fractionated to solid and liquor components by bisulfite process. The solid components were used for bioethanol production by quasi-simultaneous saccharification and fermentation. The liquor components were then converted to furfural by hydrolysis with sulfuric acid. Preliminary results showed that the concentration of furfural was highest at 18.8g/L with 0.75% sulfuric acid and reaction time of 25min. The conversion of xylose to furfural was 82.5%. Furthermore, we attempted to fractionate the liquor into hemicellulose sugars and lignin by different methods for producing potential chemicals, such as xylose, xylooligosaccharide, and lignosulfonate. Our research showed that the combination of bisulfite pretreatment and resin separation could effectively fractionate EFB components to produce bioethanol and other high value chemicals.
    Matched MeSH terms: Xylose
  12. Pretreatment of extruded Napier grass byhydrothermal process with dilute sulfuric acid and fermentation using a cellulose-hydrolyzing and xylose-assimilating yeast for ethanol production
    Ismail KSK, Matano Y, Sakihama Y, Inokuma K, Nambu Y, Hasunuma T, et al.
    Bioresour Technol, 2022 Jan;343:126071.
    PMID: 34606923 DOI: 10.1016/j.biortech.2021.126071
    One of the potential bioresources for bioethanol production is Napier grass, considering its high cellulose and hemicellulose content. However, the cost of pretreatment hinders the bioethanol produced from being economical. This study examines the effect of hydrothermal process with dilute acid on extruded Napier grass, followed by enzymatic saccharification prior to simultaneous saccharification and co-fermentation (SScF). Extrusion facilitated lignin removal by 30.2 % prior to dilute acid steam explosion. Optimum pretreatment condition was obtained by using 3% sulfuric acid, and 30-min retention time of steam explosion at 190 °C. Ethanol yield of 0.26 g ethanol/g biomass (60.5% fermentation efficiency) was attained by short-term liquefaction and fermentation using a cellulose-hydrolyzing and xylose-assimilating Saccharomyces cerevisiae NBRC1440/B-EC3-X ΔPHO13, despite the presence of inhibitors. This proposed method not only reduced over-degradation of cellulose and hemicellulose, but also eliminated detoxification process and reduced cellulase loading.
    Matched MeSH terms: Xylose*
  13. Deep eutectic solvent and inorganic salt pretreatment of lignocellulosic biomass for improving xylose recovery
    Loow YL, Wu TY, Yang GH, Ang LY, New EK, Siow LF, et al.
    Bioresour Technol, 2018 Feb;249:818-825.
    PMID: 29136937 DOI: 10.1016/j.biortech.2017.07.165
    Deep eutectic solvents (DESs) have received considerable attention in recent years due to their low cost, low toxicity, and biodegradable properties. In this study, a sequential pretreatment comprising of a DES (choline chloride:urea in a ratio of 1:2) and divalent inorganic salt (CuCl2) was evaluated, with the aim of recovering xylose from oil palm fronds (OPF). At a solid-to-liquid ratio of 1:10 (w/v), DES alone was ineffective in promoting xylose extraction from OPF. However, a combination of DES (120°C, 4h) and 0.4mol/L of CuCl2 (120°C, 30min) resulted in a pretreatment hydrolysate containing 14.76g/L of xylose, remarkably yielding 25% more xylose than the CuCl2-only pretreatment (11.87g/L). Characterization studies such as FE-SEM, BET, XRD, and FTIR confirmed the delignification of OPF when DES was implemented. Thus, the use of this integrated pretreatment system enabled xylose recoveries which were comparable with other traditional pretreatments.
    Matched MeSH terms: Xylose*
  14. Zinc, magnesium, and calcium ion supplementation confers tolerance to acetic acid stress in industrial Saccharomyces cerevisiae utilizing xylose
    Ismail KS, Sakamoto T, Hasunuma T, Zhao XQ, Kondo A
    Biotechnol J, 2014 Dec;9(12):1519-25.
    PMID: 24924214 DOI: 10.1002/biot.201300553
    Lignocellulosic biomass is a potential substrate for ethanol production. However, pretreatment of lignocellulosic materials produces inhibitory compounds such as acetic acid, which negatively affect ethanol production by Saccharomyces cerevisiae. Supplementation of the medium with three metal ions (Zn(2+) , Mg(2+) , and Ca(2+) ) increased the tolerance of S. cerevisiae toward acetic acid compared to the absence of the ions. Ethanol production from xylose was most improved (by 34%) when the medium was supplemented with 2 mM Ca(2+) , followed by supplementation with 3.5 mM Mg(2+) (29% improvement), and 180 μM Zn(2+) (26% improvement). Higher ethanol production was linked to high cell viability in the presence of metal ions. Comparative transcriptomics between the supplemented cultures and the control suggested that improved cell viability resulted from the induction of genes controlling the cell wall and membrane. Only one gene, FIT2, was found to be up-regulated in common between the three metal ions. Also up-regulation of HXT1 and TKL1 might enhance xylose consumption in the presence of acetic acid. Thus, the addition of ionic nutrients is a simple and cost-effective method to improve the acetic acid tolerance of S. cerevisiae.
    Matched MeSH terms: Xylose/metabolism*
  15. Efficient removal of lignin with the maintenance of hemicellulose from kenaf by two-stage pretreatment process
    Wan Azelee NI, Md Jahim J, Rabu A, Abdul Murad AM, Abu Bakar FD, Md Illias R
    Carbohydr Polym, 2014 Jan;99:447-53.
    PMID: 24274529 DOI: 10.1016/j.carbpol.2013.08.043
    The enhancement of lignocellulose hydrolysis using enzyme complexes requires an efficient pretreatment process to obtain susceptible conditions for the enzyme attack. This study focuses on removing a major part of the lignin layer from kenaf (Hibiscus cannabinus) while simultaneously maintaining most of the hemicellulose. A two-stage pretreatment process is adopted using calcium hydroxide, Ca(OH)₂, and peracetic acid, PPA, to break the recalcitrant lignin layer from other structural polysaccharides. An experimental screening of several pretreatment chemicals, concentrations, temperatures and solid-liquid ratios enabled the production of an optimally designed pretreatment process for kenaf. Our results showed that the pretreatment process has provide 59.25% lignin removal while maintaining 87.72% and 96.17% hemicellulose and cellulose, respectively, using 1g of Ca(OH)₂/L and a 8:1 (mL:g) ratio of liquid-Ca(OH)₂ at 50 °C for 1.5 h followed by 20% peracetic acid pretreatment at 75 °C for 2 h. These results validate this mild approach for aiding future enzymatic hydrolysis.
    Matched MeSH terms: Xylose/chemistry*
  16. Fulltext Chemical composition and molecular structure of polysaccharide-protein biopolymer from Durio zibethinus seed: extraction and purification process
    Amid BT, Mirhosseini H, Kostadinović S
    Chem Cent J, 2012 Oct 14;6(1):117.
    PMID: 23062269 DOI: 10.1186/1752-153X-6-117
    BACKGROUND: The biological functions of natural biopolymers from plant sources depend on their chemical composition and molecular structure. In addition, the extraction and further processing conditions significantly influence the chemical and molecular structure of the plant biopolymer. The main objective of the present study was to characterize the chemical and molecular structure of a natural biopolymer from Durio zibethinus seed. A size-exclusion chromatography coupled to multi angle laser light-scattering (SEC-MALS) was applied to analyze the molecular weight (Mw), number average molecular weight (Mn), and polydispersity index (Mw/Mn).

    RESULTS: The most abundant monosaccharide in the carbohydrate composition of durian seed gum were galactose (48.6-59.9%), glucose (37.1-45.1%), arabinose (0.58-3.41%), and xylose (0.3-3.21%). The predominant fatty acid of the lipid fraction from the durian seed gum were palmitic acid (C16:0), palmitoleic acid (C16:1), stearic acid (C18:0), oleic acid (C18:1), linoleic acid (C18:2), and linolenic acid (C18:2). The most abundant amino acids of durian seed gum were: leucine (30.9-37.3%), lysine (6.04-8.36%), aspartic acid (6.10-7.19%), glycine (6.07-7.42%), alanine (5.24-6.14%), glutamic acid (5.57-7.09%), valine (4.5-5.50%), proline (3.87-4.81%), serine (4.39-5.18%), threonine (3.44-6.50%), isoleucine (3.30-4.07%), and phenylalanine (3.11-9.04%).

    CONCLUSION: The presence of essential amino acids in the chemical structure of durian seed gum reinforces its nutritional value.

    Matched MeSH terms: Xylose
  17. Fulltext Exploratory Analysis of the Microbiological Potential for Efficient Utilization of Fiber Between Lantang and Duroc Pigs
    Cheng P, Wang Y, Liang J, Wu Y, Wright A, Liao X
    Front Microbiol, 2018;9:1342.
    PMID: 29988353 DOI: 10.3389/fmicb.2018.01342
    There is growing interest in the use of unconventional feed ingredients containing higher dietary fiber for pig production due to increasing prices of cereal grains and the potential health benefits of dietary fiber on host animals. This study aimed to gain insight into the community-wide microbiome population between the Chinese native Lantang pigs and the commercial Duroc pigs to uncover the microbiological mechanisms for the degradation capacity of fiber in pigs. Utilizing the metagenomics approach, we compared the phylogeny and functional capacity of the fecal microbiome from approximately 150-day-old female Lantang and Duroc pigs fed a similar diet. The structure of the fecal microbial community from the two pig breeds was different at the genus level; the number of genes associated with fiber degradation was higher in Lantang pigs. Further analysis and prediction of their functions from the fecal microbiomes of the two pig breeds revealed that the degradation capacities of fiber, branched chain fatty acids, and oligosaccharides were higher in Lantang pigs. The ability of lignocellulose bonding modules and the transport capacities of xylose, L-arabinose, ribose and methyl galactose were also higher in Lantang pigs. Similarly, the metabolic capacities of xylose, ribose, and fucose and the potential effectiveness of the tricarboxylic acid cycle (TCA) and gene abundance in the hydrogen sink pathway were higher in the fecal microbiome from Lantang pigs. Lantang pigs have a higher capacity to utilize dietary fiber than Duroc pigs, and the differences in the capability to utilize dietary fiber between the indigenous and commercial pigs could be differences in the composition and biological function of the gut microbiota.
    Matched MeSH terms: Xylose
  18. Fulltext A perspective bioproduction of xylitol by enzyme technology and future prospects
    Rafiqul, I.S.M., Mimi Sakinah, A.M.
    International Food Research Journal, 2012;19(2):405-408.
    MyJurnal
    Xylitol is a high value sugar alcohol with anticariogenic properties that is used as an ideal sweetener for diabetic patients. Industrially, xylitol is manufactured by catalytic reduction of pure xylose, which has
    some disadvantages. The fermentation process has been studied as an alternative, but its viability is dependent on the optimization of several variables. This fermentation process on an industrial-scale is not feasible due to decreased productivity. Compared to the fermentation process, enzymatic method is expected to make a substantial increase in productivity. Enzymatic xylitol production from xylose exist in lignocellulosics is an attractive and promising alternative method to the chemical process. The enzymatic method might be able to overcome the disadvantages of the chemical process. This article reviews the literature on the processes for xylitol production and identifies further ways for improved xylitol production to compete with the current chemical process.
    Matched MeSH terms: Xylose
  19. Fulltext Candida sp. as a starter culture for cocoa (Theobroma cacao L.) beans fermentation
    Mahazar, N. H., Sufian, N. F., Meor Hussin, A. S., Norhayati, H., Mathawan, M., Rukayadi, Y.
    International Food Research Journal, 2015;22(5):1783-1787.
    MyJurnal
    Two cocoa bean fermentation methods (spontaneous fermentation and the use of starter culture) for 7 days fermentation were compared in terms of safety and quality fermented beans. Candida sp. was used as a starter culture in this study. The safety of the fermented cocoa beans were measured by the growth colonies of pathogenic microorganisms namely Bacillus cereus, Escherichia coli, Salmonella sp., Staphylococcus aureus, and Pseudomonas sp., on Bacillus cereus agar, eosin-methylene blue (EMB) agar, xylose lysine deoxycholate (XLD) agar, Baird-Parker agar (BPA), and Pseudomonas agar, respectively. B. cereus, E. coli and Salmonella sp. were early present in both fermentations. Candida sp.-fermentation showed detection of B. cereus at 5.34 log10 CFU/g and absence after 24 hours of fermentation while in spontaneous-fermentation B. cereus was too few to count. Moreover, the log10 E. coli number in Candida sp.-fermentation and spontaneous-fermentation were reduced from 5.72 to 3.66 and from 7.15 to 4.46 on day 1 to day 3, respectively. There were no presences of pathogenic microorganisms on day 5 and day 7 for both fermentations. In term of quality, proximate analysis of spontaneous-fermentation resulted that the content of moisture, ash, fat, crude protein, crude fibre and carbohydrate was 56.47%, 2.32%, 3.17%, 7.02%, 28.14% and 2.88%, meanwhile for the Candida sp.-fermentation was 53.96%, 2.19%, 3.44%, 8.25%, 25.46% and 6.70%, respectively. This study showed that both fermentations are considered to be safe and there is no significant difference in proximate value in fermented cocoa beans from spontaneous-fermentation and Candida sp.-fermentation.
    Matched MeSH terms: Xylose
  20. Molecular structure, chemical properties and biological activities of Pinto bean pod polysaccharide
    Kamarudin F, Gan CY
    Int J Biol Macromol, 2016 Jul;88:280-7.
    PMID: 27044345 DOI: 10.1016/j.ijbiomac.2016.04.003
    Pinto bean pod polysaccharide (PBPP) was successfully extracted with yield of 38.5g/100g and the PBPP gave total carbohydrate and uronic acid contents of 286.2mg maltose equivalent/g and 374.3mgGal/g, respectively. The Mw of PBPP was 270.6kDa with intrinsic viscosity of 0.262dm(3)/g, which composed of mannose (2.5%), galacturonic acid (15.0%), rhamnose (4.0%), glucose (9.0%), galactose (62.2%), xylose (2.9%) and arabinose (4.3%) with trace amount of ribose and fucose. The result suggested that PBPP has a spherical conformation with a highly branched structure. Fourier Transform Infrared analysis showed that PBPP has a similar structure as commercial pectin with an esterification degree of 59.9%, whereas scanning electron microscopy study showed that the crude polysaccharide formed a thin layer of film that was made of multiple micro strands of fibre. PBPP exhibited substantial free radical scavenging activity (7.7%), metal reducing capability (2.04mmol/dm(3)) and α-amylase inhibitory activity (97.6%) at a total amount of 1mg. PBPP also exhibited high water- and oil-holding capacities (3.6g/g and 2.8g/g, respectively). At a low concentration, PBPP exhibited emulsifying activity of 39.6% with stability of 38.6%. Apart from that, PBPP was able to show thickening capability at low concentration (0.005kg/dm(3)).
    Matched MeSH terms: Xylose
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