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Fulltext Explorative Xylitol Detection from Lignocellulosic Biomass Fermentation of Coconut Husk Using HPLC C18 Column

Mariam-Aisha Fatima, Muhammad Fahmi Mehdin, Nurain Nasrudin, Neelam Shahab

Journal of Management & Science, 2018;16(2):29-38.
MyJurnal

Lignocellulosic biomass, found in wooden plant husks is a potent renewable material source which can be utilised to form various chemicals and biomaterials including polyols such as xylitol. Xylitol has been used commercially as an alternative to sucrose in many products as bulk sweetener in non-cariogenic confectionery as well as in diabetic diets and solutions for parenteral nutrition. Therefore, this study aims to optimise separation parameters of the Shimadzu high performance liquid chromatography (HPLC) (Model No: LC-20A) and quantify the potential of coconut husk as substrate for Candida albicans in producing xylitol using HPLC. Pretreatment to depolymerise components of biomass i.e. cellulose, hemicellulose and lignin were done using dilute acid hydrolysis method which yielded fermentable reducing sugars, xylose. Xylose is a monosaccharide with an aldehyde functional group, a reducing sugar which is then utilised and fermented by the yeast Candida albicans to form xylitol. In this study, the media used for fermenting pretreated coconut husk and Candida albicans is a synthetic defined (SD) minimal broth. Growth curves against concentration of reducing sugar were plotted to determine utilisation and production trends with specific mixes of carbon sources. The presence of reducing sugars were tested using 3,5-dinitrosalicylic acid (DNS) assay in pretreated coconut husk yielded 13.22 g/L. In order to analyse the product with HPLC, an existing protocol is modified for Hypersil GOLD™ C18 column with acetonitrile as the mobile phase. Results obtained from HPLC analyses using developed protocol suggested the formation of xylitol from the fermentation of pretreated husk by Candida albicans. These can be followed by purification of fermented media in obtaining a better separation of contaminating peaks.

Matched MeSH terms: Xylose
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
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
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
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*
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*
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
Fulltext Sulfated galactans from red seaweeds and their potential applications

Lim, Yi-Yi, Lee, Wei-Kang, Leow, Adam Thean-Chor, Parameswari Namasivayam, Janna-Ong Abdullah, Ho, Chai-Ling

The Pertanika Journal of Scholarly Research Reviews, 2018;4(2):1-17.
MyJurnal

Red seaweeds (Rhodophyta) produce a variety of sulfated galactans in their cell wall matrix and intercellular space, contributing up to 50-60 % of their total dry weight. These sulfated polysaccharides are made up of galactose disaccharides substituted with sulfate, methoxyl, pyruvic acid, or non-galactose monosaccharides (e.g. xylose, glucose and mannose). They are required by the Rhodophytes for protection against pathogen, desiccation, tidal waves and extreme changes in pH, temperature and salinity. Since ancient times, sulfated galactans from red seaweeds, such as agar and carrageenan, have been consumed as human foods and later being used in traditional medicine. Nowadays, some red seaweeds are cultivated and exploited for commercial uses in various fields. In this review, different types of sulfated galactans found in red seaweeds and their current and potential uses in food, biotechnology, medical and pharmaceutical industries are discussed.

Matched MeSH terms: Xylose
Structural Characterization and Immunomodulatory Activity of a Polysaccharide from Eurycoma longifolia

He P, Dong Z, Wang Q, Zhan QP, Zhang MM, Wu H

J Nat Prod, 2019 02 22;82(2):169-176.
PMID: 30714735 DOI: 10.1021/acs.jnatprod.8b00238

A polysaccharide, Ali-1, was isolated from the roots of Eurycoma longifolia, a popular traditional medicinal herb in Malaysia. The structure of Ali-1 was characterized by monosaccharide, methylation, and NMR data analyses. The average molecular weight of Ali-1 is 14.3 ku, and it is composed of arabinose (14.31%), xylose (57.69%), galacturonic acid (13.03%), and glucuronic acid (14.86%). The main chain comprises (1→4)-linked xylose residues. It has branch points in the main chain; (1→2,4)-linked xylose residues, 1,2-linked glucuronic acid residues, and 1,2-linked arabinose residues form the branches, and the branches are terminated with T-linked galacturonic acid residues and T-linked arabinose residues. Ali-1 significantly improves the pinocytic and phagocytic abilities of RAW264.7 cells and facilitates cytokine secretion according to an immunostimulation assay. These results demonstrate that Ali-1 has potential as a functional supplement for people with compromised immune systems.

Matched MeSH terms: Xylose
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
Co-expression of TAL1 and ADH1 in recombinant xylose-fermenting Saccharomyces cerevisiae improves ethanol production from lignocellulosic hydrolysates in the presence of furfural

Hasunuma T, Ismail KSK, Nambu Y, Kondo A

J Biosci Bioeng, 2014 Feb;117(2):165-169.
PMID: 23916856 DOI: 10.1016/j.jbiosc.2013.07.007

Lignocellulosic biomass dedicated to bioethanol production usually contains pentoses and inhibitory compounds such as furfural that are not well tolerated by Saccharomyces cerevisiae. Thus, S. cerevisiae strains with the capability of utilizing both glucose and xylose in the presence of inhibitors such as furfural are very important in industrial ethanol production. Under the synergistic conditions of transaldolase (TAL) and alcohol dehydrogenase (ADH) overexpression, S. cerevisiae MT8-1X/TAL-ADH was able to produce 1.3-fold and 2.3-fold more ethanol in the presence of 70 mM furfural than a TAL-expressing strain and a control strain, respectively. We also tested the strains' ability by mimicking industrial ethanol production from hemicellulosic hydrolysate containing fermentation inhibitors, and ethanol production was further improved by 16% when using MT8-1X/TAL-ADH compared to the control strain. Transcript analysis further revealed that besides the pentose phosphate pathway genes TKL1 and TAL1, ADH7 was also upregulated in response to furfural stress, which resulted in higher ethanol production compared to the TAL-expressing strain. The improved capability of our modified strain was based on its capacity to more quickly reduce furfural in situ resulting in higher ethanol production. The co-expression of TAL/ADH genes is one crucial strategy to fully utilize undetoxified lignocellulosic hydrolysate, leading to cost-competitive ethanol production.

Matched MeSH terms: Xylose/metabolism*
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

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