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.
Herbicides are inevitable inputs to control excessive weed in crop land, particularly where modern agricultural practices such as conservation tillage, are opted. Intensive farming has increased the market value of herbicides among the other pesticides. Although herbicides are effective in controlling weed population, administration of this synthetic chemicals may alter the soil microbial community causing potential increase of plant pathogens. Moreover, herbicides may also have nontarget effects on the cultivated crops making them more susceptible to diseases. Actions of herbicides in soil that either stimulate microbial growth or wipe out some microbial population may create space for the thrivial of opportunistic fungi. Previous studies showed that white rot fungi are more tolerant to herbicides as they produce lignin degrading enzymes that are highly oxidative, non-specific and are able to transform a wide range of herbicides. Besides that, this group of fungi can grow on agricultural waste substrates. Influence of these herbicides on soil microbial ecosystem and interactions of plants and pathogenic white rot fungi modulate disease development in plant hosts.
The biggest agricultural sector that contributes to the Malaysian economy is the oil palm industry. The effluent generated during the production of crude palm oil known as palm oil mill effluent (POME). POME undergoes anaerobic treatment that requires long retention time and produces large amount of methane that consequently contributes to global warming. In this study, an isolated bacteria was selected based on its ability to degrade kraft lignin (KL) and identified as Ochrobactrum sp. The bacteria were able to treat POME (from anaerobic pond) under the aerobic condition without addition of nutrient, resulting in a significant chemical oxygen demand (COD) removal of 71 %, removal rate of 1385 mg/l/day, and 12.3 times higher than that of the ponding system. It has also resulted in 60 % removal of ammoniacal nitrogen and 55 % of total polyphenolic after 6-day treatment period with the detection of lignocellulolytic enzymes.
Oil palm (Elaeis guineensis Jacq.) is one of the most planted trees in Malaysia for the palm oil production. Thus, solid biomass had been generated from this industry such as empty fruit bunch, shell, mesocarp fibre, frond and trunk produced that causes problematic to the nation and expected to escalate up to 85-110 million tonnes by 2020. Besides that, palm oil mill effluent and excessive steam also generated from the production of palm oil. In situ hydrothermal pretreatment means the utilisation of excessive steam produced by the oil palm mill and at the same time, generating value added product as well as reducing the biomass. Oil palm biomass is rich in lignocellulosic materials which comprised of lignin, hemicellulose and cellulose. Refinement of lignocellulosic from oil palm biomass can be utilised to form fermentable sugar, bioethanol and other potential chemicals. Recalcitrant property of lignocellulosic reduces the ability of enzymes to penetrate, thus pretreatment is required prior to hydrolysis process. Pretreatment can be either physical, chemical, biological or combined. In this review paper, three types of hydrothermal pretreatment were discussed as suitable in situ pretreatment process for oil palm biomass; in palm oil mill. The suitability was measured based on the availability of excess steam and energy in the mill. Furthermore, physicochemical pretreatment also facilitate the saccharification process, whereby it loosened the lignocellulose structure and increase the surface area. The effects and factors in choosing right pretreatment are highlighted in this paper.
Nanofibrillated cellulose (NFCs) were extracted from sugar palm fibres (SPS) in two separate stages; delignification and mercerization to remove lignin and hemicellulose, respectively. Subsequently, the obtained cellulose fibres were then mechanically extracted into nanofibres using high pressurized homogenization (HPH). The diameter distribution sizes of the isolated nanofibres were dependent on the cycle number of HPH treatment. TEM micro-images displayed the decreasing trend of NFCs diameter, from 21.37 to 5.5 nm when the number of cycle HPH was increased from 5 to 15 cycles, meanwhile TGA and XRD analysis showed that the degradation temperature and crystallinity of the NFCs were slightly increased from 347 to 347.3 °C and 75.38 to 81.19% respectively, when the number of cycles increased. Others analysis also were carried on such as FT-IR, FESEM, AFM, physical properties, zeta potential and yield analysis. The isolated NFCs may be potentially applied in various application, such as tissue engineering scaffolds, bio-nanocomposites, filtration media, bio-packaging and etc.
The valorization of lignin to replace phenol is significant in the production of phenolic resins. However, a great challenge is to produce lignin-based resin (LR) with a suitable viscosity and high substitution rate of lignin to phenol. In this study, LRs were produced using hardwood technical lignin derived from the pulping industry. Structural analysis of the LRs indicated that the unsubstituted para and ortho carbon atoms of the aromatic ring influenced the curing temperature and activation energy of the resins. The curing kinetics and thermal decomposition study implied that urea and methylene groups in cured LRs were significant factors that affected the thermal stability negatively. The prepared LRs showed desirable features if used as adhesives to make plywood. This is the first approach in which a substitution rate of up to 65 % is achieved for low-reactive-site hardwood lignin, which provides a solution to the challenge of the simultaneous realization of the high addition of lignin and the adaptive viscosity of resins.
Xylem is an essential conductive tissue in vascular plants, and secondary cell wall polymers found in xylem vessel elements, such as cellulose, hemicellulose, and lignin, are promising sustainable bioresources. Thus, understanding the molecular mechanisms underlying xylem vessel element differentiation is an important step towards increasing woody biomass and crop yields. Establishing in vitro induction systems, in which vessel element differentiation is induced by phytohormonal stimuli or by overexpression of specific transcription factors, has been vital to this research. In this review, we present an overview of these in vitro induction systems, and describe two recently developed in vitro induction systems, VISUAL (Vascular cell Induction culture System Using Arabidopsis Leaves) and the KDB system. Furthermore, we discuss the potentials and limitations of each of these new in vitro induction systems for advancing our understanding of the molecular mechanisms driving xylem vessel element differentiation.
e effects of biological pretreatment on the rubberwood (Hevea brasiliensis), was evaluated after cultivation of white rot fungi Ceriporiopsis subvermispora, Trametes versicolor, and a mixed culture of C. subvermispora and T. versicolor. The analysis of chemical compositions indicated that C. subvermispora had greater selectivity for lignin degradation with the highest lignin and hemicellulose loss at 45.06% and 42.08%, respectively, and lowest cellulose loss (9.50%) after 90 days among the tested samples. X-ray analysis showed that pretreated samples had a higher crystallinity than untreated samples. The sample pretreated by C. subvermispora presented the highest crystallinity of all the samples which might be caused by the selective degradation of amorphous components. Fourier transform infrared (FT-IR) spectroscopy demonstrated that the content of lignin and hemicellulose decreased during the biological pretreatment process. A study on hydrolysis of rubberwood treated with C. subvermispora, T. versicolor, and mixed culture for 90 days resulted in an increased sugar yield of about 27.67%, 16.23%, and 14.20%, respectively, as compared with untreated rubberwood (2.88%). The results obtained demonstrate that rubberwood is a potential raw material for industrial applications and white rot fungus C. subevermispora provides an effective method for improving the enzymatic hydrolysis of rubberwood.
In this cross-sectional investigation, the primary objective was to explore the correlation between the consumption of polyphenols and the likelihood of non-alcoholic fatty liver disease (NAFLD) in the adult population participating in the Hoveyzeh cohort. Data from the Hoveyzeh cohort study, part of the Persian Cohort Study, involving 10,009 adults aged 35-70, were analyzed. Exclusions were made for missing data, extreme energy intake, and liver cancer patients. Dietary habits were assessed using a food frequency questionnaire, and polyphenol intake was calculated using the Phenol Explorer database. Logistic regression analyses, adjusted for confounders, were performed to assess the relationship between polyphenol subclasses (total polyphenols, total flavonoids, phenolic acid, and lignin) and NAFLD. Among 9894 participants, those in the highest quintile of total polyphenol (OR 0.65, CI 0.5-0.84; P = 0.007), phenolic acid (OR 0.67, CI 0.52-0.86; P lignin intake (OR 0.69, CI 0.52-0.87; P = 0.001) demonstrated lower odds of NAFLD compared to the lowest quintile, even after adjusting for confounding factors. However, no significant association was found between total flavonoid intake and NAFLD (OR 1.26, CI 0.96-1.67; P = 0.47). Subgroup analysis indicated a significant inverse association between total polyphenols and NAFLD in women (OR 0.64, CI 0.42-0.93; P = 0.001). Higher intake of total polyphenols, phenolic acid, and lignin was associated with reduced odds of NAFLD among adults in the Hoveyzeh cohort. This suggests that dietary patterns rich in these polyphenols may play a role in mitigating the risk of NAFLD. Further interventional and longitudinal studies are needed to validate these findings and explore potential preventive strategies involving polyphenol-rich diets.
Ionic liquids (ILs) have been used as an alternative green solvent for lignocelluloses pretreatment. However, being a salt, ILs exhibit an inhibitory effect on cellulases activity, thus making the subsequent saccharification inefficient. The aim of the present study is to produce salt-tolerant cellulases, with the rationale that the enzyme also tolerant to the presence of ILs. The enzyme was produced from a locally isolated halophilic strain and was characterized and assessed for its tolerance to different types of ionic liquids. The results showed that halophilic cellulases produced from Aspergillus terreus UniMAP AA-6 exhibited higher tolerance to ILs and enhanced thermo stability in the presence of high saline conditions.
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.
Conversion of glucose, empty fruit bunch (efb) and kenaf to levulinic acid over a new hybrid catalyst has been investigated in this study. The characterization and catalytic performance results revealed that the physico-chemical properties of the new hybrid catalyst comprised of chromium chloride and HY zeolite increased the levulinic acid production from glucose compared to the parent catalysts. Optimization of the glucose conversion process using two level full factorial designs (2(3)) with two center points reported 55.2% of levulinic acid yield at 145.2 °C, 146.7 min and 12.0% of reaction temperature, reaction time and catalyst loading, respectively. Subsequently, the potential of efb and kenaf for producing levulinic acid at the optimum conditions was established after 53.2% and 66.1% of efficiencies were reported. The observation suggests that the hybrid catalyst has a potential to be used in biomass conversion to levulinic acid.
This study was conducted to evaluate the potential antioxidant activity of lignin obtained from black liquor, a hazardous waste product generated during the extraction of palm oil. Antioxidant potential of the extracted lignin was evaluated by dissolving the extracted samples in 2 different solvent systems, namely, 2-methoxy ethanol and DMSO. Results revealed high percent inhibition of the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical in the lignin sample dissolved in 2-methoxy ethanol over DMSO (concentration range of 1-100 microg/ml). Lignin extracted in 2-methoxy ethanol exhibited higher inhibition percentage (at 50 microg/ml, 84.2%), whereas a concentration of 100 microg/ml was found to be effective in the case of the DMSO solvent (69.8%). Fourier transform infrared (FTIR) spectrometry revealed that the functional groups from the extracted lignin and commercial lignin were highly similar, indicating the purity of the lignin extracted from black liquor. These results provide a strong basis for further applications of lignin in the food industry and also illustrate an eco-friendly approach to utilize oil palm black liquor.
Ethanolic fermentation using Saccharomyces cerevisiae was carried out on three types of hydrolysates produced from lignocelulosic biomass which are commonly found in Malaysia such as oil palm trunk, rubberwood and mixed hardwood. The effect of fermentation temperature and pH of hydrolysate was evaluated to optimize the fermentation efficiency which defined as maximum ethanol yield in minimum fermentation time. The fermentation process using different temperature of 25 degrees Celsius, 30 degrees Celsius and 40 degrees Celsius were performed on the prepared fermentation medium adjusted to pH 4, pH 6 and pH 7, respectively. Results showed that the fermentation time was significantly reduced with the increase of temperature but an adverse reduction in ethanol yield was observed using temperature of 40 degrees Celsius. As the pH of hydrolysate became more acidic, the ethanol yield increased. Optimum fermentation efficiency for ethanolic fermentation of lignocellulosic hydrolysates using S. cerevisiae can be obtained using 33.2 degrees Celsius and pH 5.3.
The present study reveals the perspective and challenges of bio-ethanol production from lignocellulosic materials in Malaysia. Malaysia has a large quantity of lignocellulosic biomass from agriculture waste, forest residues and municipal solid waste. In this work, the current status in Malaysia was laconically elucidated, including an estimation of biomass availability with a total amount of 47,402 dry kton/year. Total capacity and domestic demand of second-generation bio-ethanol production in Malaysia were computed to be 26,161 ton/day and 6677 ton/day, respectively. Hence, it was proven that the country's energy demand can be fulfilled with bio-ethanol if lignocellulosic biomass were fully converted into bio-ethanol and 19% of the total CO(2) emissions in Malaysia could be avoided. Apart from that, an integrated national supply network was proposed together with the collection, storage and transportation of raw materials and products. Finally, challenges and obstacles in legal context and policies implementation were elaborated, as well as infrastructures shortage and technology availabilities.
Recently, second-generation bio-ethanol (SGB), which utilizes readily available lignocellulosic biomass has received much interest as another potential source of liquid biofuel comparable to biodiesel. Thus the aim of this paper is to determine the exergy efficiency and to compare the effectiveness of SGB and palm methyl ester (PME) processes. It was found that the production of bio-ethanol is more thermodynamically sustainable than that of biodiesel as the net exergy value (NExV) of SGB is 10% higher than that of PME. Contrarily, the former has a net energy value (NEV) which is 9% lower than the latter. Despite this, SGB is still strongly recommended as a potential biofuel because SGB production can help mitigate several detrimental impacts on the environment.
Hemicelluloses from oil palm frond (OPF) were extracted using 3 M potassium hydroxide (KOH) for 4 h at 40 degrees C with stirring at 400 rpm to obtain hemicelluloses A and B. The total yield of the hemicellulose isolated from OPF was 33% (dry weight). Both hemicelluloses A and B were then subjected to hydrothermal treatment at 121 degrees C and 1.03 x 10(5) Pa for 10, 30, and 50 min. Physicochemical characterizations of hydrothermally treated hemicelluloses, such as Klason lignin content and reducing sugar content, were performed to study the effect of autohydrolysis processing on OPF-derived hemicelluloses. It was shown that Klason lignin content in hemicellulose A was higher than that in hemicellulose B and decreased after hydrothermal treatment. Hydrothermal treatment enhanced the solubility of hemicelluloses, which reflects their higher reducing sugar content. Monosaccharide analysis using HPLC showed that xylose was the predominant monosaccharide for both hemicelluloses A and B.
Next Generation Sequencing has provided comprehensive, affordable and high-throughput DNA sequences for Single Nucleotide Polymorphism (SNP) discovery in Acacia auriculiformis and Acacia mangium. Like other non-model species, SNP detection and genotyping in Acacia are challenging due to lack of genome sequences. The main objective of this study is to develop the first high-throughput SNP genotyping assay for linkage map construction of A. auriculiformis x A. mangium hybrids.
A laboratory-scale study of bioconversion of local lignocellulosic material, oil palm biomass (OPB) was conducted by evaluating the enzyme production through microbial treatment in solid state bioconversion (SSB). OPB in the form of empty fruit bunches (EFB) was used as a solid substrate and treated with the white-rot fungus, Phanerochaete chrysosporium, to produce ligninase. The results showed that the highest ligninase activity of 400.27 U/liter was obtained at day 12 of fermentation. While the optimum study indicated the enzyme production of 1472.8 U/liter with moisture content of 50%, 578.7 U/liter with 10% v/w of inoculum size, and 721.8 U/liter with co-substrate concentration of 1% (w/w) at days 9, 9 and 12 of fungal treatment, respectively. The parameters glucosamine and reducing sugar were observed to evaluate the growth and substrate utilization in the experiment.
The lower termite, Coptotermes curvignathus, is one of the most prominent plantation pests that feed upon, digest, and receive nourishment from exclusive lignocellulose diets. The objective of this study was to examine the utilization of sole carbon sources by isolated culturable aerobic bacteria among communities from the gut and foraging pathway of C. curvignathus. We study the bacteria occurrence from the gut of C. curvignathus and its surrounding feeding area by comparing the obtained phenotypic fingerprint with Biolog's extensive species library. A total of 24 bacteria have been identified mainly from the family Enterobacteriaceae from the identification of Biolog Gen III. Overall, the bacteria species in the termite gut differ from those of foraging pathway within a location, except Acintobacter baumannii, which was the only bacteria species found in both habitats. Although termites from a different study area do not have the same species of bacteria in the gut, they do have a bacterial community with similar role in degrading certain carbon sources. Sugars were preferential in termite gut isolates, while nitrogen carbon sources were preferential in foraging pathway isolates. The preferential use of specific carbon sources by these two bacterial communities reflects the role of bacteria for regulation of carbon metabolism in the termite gut and foraging pathway.