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1.
J Sci Food Agric ; 102(10): 4046-4053, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-34997572

RESUMO

BACKGROUND: Palm kernel is the edible seed of the oil palm fruit obtained during the palm oil milling process. For efficient processing and storage, the moisture content of palm kernel must be reduced to an optimal level by drying. This study aimed to see how drying influenced the physical structure and physicochemical properties of palm kernel and oil. Before and after drying, the free fatty acid (FFA), color, fatty acid composition, Fourier transform infrared, thermal properties and structure of palm kernel were investigated. RESULTS: Results show that drying significantly (P < 0.05) reduced FFA and color of palm kernel oil. Drying also significantly affected (P < 0.05) composition of some fatty acids in palm kernel oil such as capric acid, lauric acid, myristic acid, palmitic acid and oleic acid. However, drying did not affect palm kernel and palm kernel oil functional groups and thermal properties. After drying, structural damage of palm kernel was observed. CONCLUSION: Based on these findings, the quality of kernel oil may be maintained after drying, and it can even be improved based on lower FFA content. © 2022 Society of Chemical Industry.


Assuntos
Ácidos Graxos , Óleos de Plantas , Ácidos Graxos/química , Ácidos Graxos não Esterificados/análise , Óleo de Palmeira/análise , Óleos de Plantas/química , Sementes/química
2.
Polymers (Basel) ; 13(23)2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-34883717

RESUMO

In the effort to produce renewable and biodegradable polymers, more studies are being undertaken to explore environmentally friendly sources to replace petroleum-based sources. The oil palm industry is not only the biggest vegetable-oil producer from crops but also one the biggest producers of residual oil that cannot be used for edible purposes due to its low quality. In this paper the development of biopolymers from residual palm oil, residual palm oil with 10% jatropha oil, and residual palm oil with 10% algae oil as additives were explored. Polyols from the different oils were prepared by epoxydation with peroxyacetic acid and alcoholysis under the same conditions and further reacted with poly isocyanate to form polyurethanes. Epoxidized oils, polyols and polyurethanes were analyzed by different techniques such as TGA, DSC, DMA, FTIR and H-NMR. Overall, although the IV of algae oil is slightly higher than that of jatropha oil, the usage of algae oil as additive into the residual palm oil was shown to significantly increase the hard segments and thermal stability of the bio polyurethane compared to the polymer with jatropha oil. Furthermore, when algae oil was mixed with the residual palm oil, it was possible to identify phosphate groups in the polyol which might enhance the fire-retardant properties of the final biopolymer.

3.
Foods ; 10(11)2021 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-34829028

RESUMO

In recent years, downstream bioprocessing industries are venturing into less tedious, simple, and high-efficiency separation by implementing advanced purification and extraction methods. This review discusses the separation of proteins, with the main focus on amylase as an enzyme from agricultural waste using conventional and advanced techniques of extraction and purification via a liquid biphasic system (LBS). In comparison to other methods, such as membrane extraction, precipitation, ultrasonication, and chromatography, the LBS stands out as an efficient, cost-effective, and adaptable developing method for protein recovery. The two-phase separation method can be water-soluble polymers, or polymer and salt, or alcohol and salt, which is a simpler and lower-cost method that can be used at a larger purification scale. The comparison of different approaches in LBS for amylase purification from agricultural waste is also included. Current technology has evolved from a simple LBS into microwave-assisted LBS, liquid biphasic flotation (LBF), thermoseparation (TMP), three-phase partitioning (TPP), ultrasound-assisted LBS, and electrically assisted LBS. pH, time, temperature, and concentration are some of the significant research parameters considered in the review of advanced techniques.

4.
Bioresour Technol ; 332: 125070, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33878542

RESUMO

The influence of biomass cellulosic content on biochar nanopore structure and adsorption capacity in aqueous phase was scarcely reported. Commercial cellulose (100% cellulose), oil palm frond (39.5% cellulose), and palm kernel shell (20.5% cellulose) were pyrolyzed AT 630 °C, characterized and tested for the adsorption of iodine and organic contaminants. The external surface area and average pore size increased with cellulosic content, where commercial cellulose formed biochar with external surface area of 95.4 m2/g and average pore size of 4.1 nm. The biochar from commercial cellulose had the largest adsorption capacities: 371.40 mg/g for iodine, 86.7 mg/L for tannic acid, 17.89 mg/g for COD and 60.35 mg/g for colour, while biochar from palm kernel shell had the least adsorption capacities. The cellulosic content reflected the differences in biochar nanopore structure and adsorption capacities, signifying the suitability of highly cellulosic biomass for producing biochar to effectively treat wastewater.


Assuntos
Nanoporos , Adsorção , Biomassa , Carvão Vegetal
5.
Environ Pollut ; 269: 116197, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33316496

RESUMO

In order to meet the growing demand for adsorbents to treat wastewater effectively, there has been increased interest in using sustainable biomass feedstocks. In this present study, the dermal tissue of oil palm frond was pyrolyzed with superheated steam at 500 °C to produce nanoporous biochar as bioadsorbent. The effect of operating conditions was investigated to understand the adsorption mechanism and to enhance the adsorption of phenol and tannic acid. The biochar had a microporous structure with a Brunauer-Emmett-Teller surface area of 422 m2/g containing low polar groups. The adsorption capacity of 62.89 mg/g for phenol and 67.41 mg/g for tannic acid were obtained using 3 g/L biochar dosage after 8 h of treatment at solution pH of 6.5 and temperature of 45 °C. The Freundlich model had the best fit to the isotherm data of phenol (R2 of 0.9863), while the Langmuir model best elucidated the isotherm data of tannic acid (R2 of 0.9632). These indicated that the biochar-phenol interface was associated with a heterogeneous multilayer sorption mechanism, while the biochar-tannic acid interface had a nonspecific monolayer sorption mechanism. The residual concentration of 26.3 mg/L phenol and 23.1 mg/L tannic acid was achieved when treated from 260 mg/L three times consecutively with 1 g/L biochar dosage, compared to a reduction to 72.3 mg/L phenol and 69.9 mg/L tannic acid using 3 g/L biochar dosage in a single treatment. The biochar exhibited effective adsorption of phenol and tannic acid, making it possible to treat effluents that contain varieties of phenolic compounds.


Assuntos
Pirólise , Poluentes Químicos da Água , Adsorção , Carvão Vegetal , Cinética , Fenol/análise , Fenóis/análise , Vapor , Taninos , Poluentes Químicos da Água/análise
6.
Food Sci Nutr ; 8(4): 1777-1787, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32328243

RESUMO

This study was carried out to compare the antioxidant and nutritional properties of coconut (Cocos nucifera L.) sap with other natural sources of sugar such as sugar palm (Borassus flabellifer) and sugarcane (Saccharum officinarum L.). Coconut sap and juice from sugar palm and sugarcane were analyzed for proximate composition, pH and total soluble solid (TSS), color, sugar profile, vitamin profile, antioxidant properties (total phenolic contents, DPPH, FRAP, and ABTS), and mineral content. The results indicated that coconut sap possesses high DPPH (23.42%), FRAP (2.09 mM/ml), and ABTS (21.85%) compared with the juices. Coconut sap also had high vitamin C (116.19 µg/ml) and ash (0.27%) contents, especially in potassium (960.87 mg/L) and sodium (183.21 mg/L) which also indicating high content of minerals. These properties showed that coconut sap could be served as a potential healthier sugar source compared with sugar palm and sugarcane juices.

7.
J Mech Behav Biomed Mater ; 97: 58-64, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31100486

RESUMO

This paper demonstrates the potential use of toy-bricks as the building block of a mechanical tensile testing instrument for the mechanical characterisation of natural fibres. A table-top tensile testing instrument was developed using LEGO parts (Mindstorms EV3 and Technics) and a 2 kg capacity load cell, whereas deformation modes were programmed in an open source programming language. Experimental work was conducted on oil palm fibres under different tensile modes (i.e. constant deformation, triple-twisted-tension and deformation-relaxation modes), which showed anisotropic-viscoelastic behaviour, and microstructural damages due to deformation.


Assuntos
Lignina/química , Teste de Materiais/instrumentação , Óleo de Palmeira/química , Anisotropia , Fenômenos Biomecânicos , Elasticidade , Estresse Mecânico , Resistência à Tração , Viscosidade
8.
Int J Biol Macromol ; 132: 592-599, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30922914

RESUMO

This research aimed to improve the stability of Chlorella-Alginate Beads (CABs) by zeolite molecular sieves 13X. Dissolution time of synthesized Zeolite-Algal-Alginate Beads (ZABs) in a chelating agent revealed a significant improvement on the beads stability (78.5 ±â€¯0.5 min) compared to the control beads (51.5 ±â€¯0.5 min) under the optimum conditions of zeolite/alginate (1.5:1), pH 5 and 2% of beads. Monitoring cell growth during 5 days of incubation showed good biocompatibility of zeolite 13X. Scanning electron microscopy (SEM) indicated rough surface and spherical shapes of ZABs. Energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared spectroscopy (FTIR) of ZABs confirmed the presence of zeolite 13X within the matrix. The zeta potential value of ZABs indicated that the beads were relatively stable. The findings of this research showed that zeolite molecular sieves 13X have the potential to improve the stability of algal-alginate beads compared to common beads.


Assuntos
Alginatos/química , Chlorella/química , Microesferas , Zeolitas/química , Estabilidade de Medicamentos , Concentração de Íons de Hidrogênio , Teste de Materiais
9.
Biomed Res Int ; 2018: 6563196, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30643814

RESUMO

The interest in utilizing algae for wastewater treatment has been increased due to many advantages. Algae-wastewater treatment system offers a cost-efficient and environmentally friendly alternative to conventional treatment processes such as electrocoagulation and flocculation. In this biosystem, algae can assimilate nutrients in the wastewater for their growth and simultaneously capture the carbon dioxide from the atmosphere during photosynthesis resulting in a decrease in the greenhouse gaseousness. Furthermore, the algal biomass obtained from the treatment process could be further converted to produce high value-added products. However, the recovery of free suspended algae from the treated effluent is one of the most important challenges during the treatment process as the current methods such as centrifugation and filtration are faced with the high cost. Immobilization of algae is a suitable approach to overcome the harvesting issue. However, there are some drawbacks with the common immobilization carriers such as alginate and polyacrylamide related to low stability and toxicity, respectively. Hence, it is necessary to apply a new carrier without the mentioned problems. One of the carriers that can be a suitable candidate for the immobilization is zeolite. To date, various types of zeolite have been used for the immobilization of cells of bacteria and yeast. If there is any possibility to apply them for the immobilization of algae, it needs to be considered in further studies. This article reviews cell immobilization technique, biomass immobilization onto zeolites, and algal immobilization with their applications. Furthermore, the potential application of zeolite as an ideal carrier for algal immobilization has been discussed.


Assuntos
Biomassa , Células Imobilizadas/metabolismo , Gases de Efeito Estufa/metabolismo , Zeolitas/química
10.
Waste Manag ; 67: 95-105, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28527863

RESUMO

In Malaysia, the amount of food waste produced is estimated at approximately 70% of total municipal solid waste generated and characterised by high amount of carbohydrate polymers such as starch, cellulose, and sugars. Considering the beneficial organic fraction contained, its utilization as an alternative substrate specifically for bioethanol production has receiving more attention. However, the sustainable production of bioethanol from food waste is linked to the efficient pretreatment needed for higher production of fermentable sugar prior to fermentation. In this work, a modified sequential acid-enzymatic hydrolysis process has been developed to produce high concentration of fermentable sugars; glucose, sucrose, fructose and maltose. The process started with hydrothermal and dilute acid pretreatment by hydrochloric acid (HCl) and sulphuric acid (H2SO4) which aim to degrade larger molecules of polysaccharide before accessible for further steps of enzymatic hydrolysis by glucoamylase. A kinetic model is proposed to perform an optimal hydrolysis for obtaining high fermentable sugars. The results suggested that a significant increase in fermentable sugar production (2.04-folds) with conversion efficiency of 86.8% was observed via sequential acid-enzymatic pretreatment as compared to dilute acid pretreatment (∼42.4% conversion efficiency). The bioethanol production by Saccharomyces cerevisiae utilizing fermentable sugar obtained shows ethanol yield of 0.42g/g with conversion efficiency of 85.38% based on the theoretical yield was achieved. The finding indicates that food waste can be considered as a promising substrate for bioethanol production.


Assuntos
Biocombustíveis , Carboidratos , Fermentação , Alimentos , Eliminação de Resíduos , Etanol , Hidrólise , Malásia
11.
Biotechnol Rep (Amst) ; 10: 44-48, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28352523

RESUMO

Immobilisation of cyclodextrin glucanotransferase (CGTase) on nanofibres was demonstrated. CGTase solution (1% v/v) and PVA (8 wt%) solution were mixed followed by electrospinning (-9 kV, 3 h). CGTase/PVA nanofibres with an average diameter of 176 ± 46 nm were successfully produced. The nanofibres that consist of immobilised CGTase were crosslinked with glutaraldehyde vapour. A CGTase/PVA film made up from the same mixture and treated the same way was used as a control experiment. The immobilised CGTase on nanofibres showed superior performance with nearly a 2.5 fold higher enzyme loading and 31% higher enzyme activity in comparison with the film.

12.
Appl Biochem Biotechnol ; 175(4): 1817-42, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25427594

RESUMO

Nanobiocatalysis is a new frontier of emerging nanosized material support in enzyme immobilization application. This paper is about a comprehensive review on cellulose nanofibers (CNF), including their structure, surface modification, chemical coupling for enzyme immobilization, and potential applications. The CNF surface consists of mainly -OH functional group that can be directly interacted weakly with enzyme, and its binding can be improved by surface modification and interaction of chemical coupling that forms a strong and stable covalent immobilization of enzyme. The knowledge of covalent interaction for enzyme immobilization is important to provide more efficient interaction between CNF support and enzyme molecule. Enzyme immobilization onto CNF is having potential for improving enzymatic performance and production yield, as well as contributing toward green technology and sustainable sources.


Assuntos
Celulose/química , Enzimas Imobilizadas/química , Nanofibras/química , Adsorção , Reagentes de Ligações Cruzadas/química , Química Verde , Nanofibras/ultraestrutura , Propriedades de Superfície
13.
Bioresour Technol ; 169: 428-438, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25079208

RESUMO

The effect of different aeration rates on the organic matter (OM) degradation during the active phase of oil palm empty fruit bunch (EFB)-rabbit manure co-composting process under constant forced-aeration system has been studied. Four different aeration rates, 0.13 L min(-1) kg(DM)(-1),0.26 L min(-1) kg(DM)(-1),0.49 L min(-1) kg(DM)(-1) and 0.74 L min(-1) kg(DM)(-1) were applied. 0.26 L min(-1) kg(DM)(-1) provided enough oxygen level (10%) for the rest of composting period, showing 40.5% of OM reduction that is better than other aeration rates. A dynamic mathematical model describing OM degradation, based on the ratio between OM content and initial OM content with correction functions of moisture content, free air space, oxygen and temperature has been proposed.


Assuntos
Arecaceae/química , Frutas/química , Modelos Teóricos , Aerobiose , Animais , Biodegradação Ambiental , Carbono/análise , Condutividade Elétrica , Umidade , Concentração de Íons de Hidrogênio , Cinética , Nitrogênio/análise , Compostos Orgânicos/isolamento & purificação , Oxigênio , Coelhos , Solo/química , Temperatura , Termogravimetria
14.
Enzyme Microb Technol ; 64-65: 52-9, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25152417

RESUMO

In this study, the potential of electrohydrodynamic atomization or electrospraying to produce nanometer-order CGTase particles from aqueous suspension was demonstrated. CGTase enzyme was prepared in acetate buffer solution (1% v/v), followed by electrospraying in stable Taylor cone-jet mode. The deposits were collected on aluminium foil (collector) at variable distances from the tip of spraying needle, ranging from 10 to 25 cm. The Coulomb fission that occurs during electrospraying process successfully transformed the enzyme to the solid state without any functional group deterioration. The functional group verification was conducted by FTIR analysis. Comparison between the deposit and the as-received enzyme in dry state indicates almost identical spectra. By increasing the distance of the collector from the needle tip, the average particle size of the solidified enzyme was reduced from 200±117 nm to 75±34 nm. The average particle sizes produced from the droplet fission were in agreement with the scaling law models. Enzyme activity analysis showed that the enzyme retained its initial activity after the electrospraying process. The enzyme particles collected at the longest distance (25 cm) demonstrated the highest enzyme activity, which indicates that the activity was controlled by the enzyme particle size.


Assuntos
Proteínas de Bactérias/química , Glucosiltransferases/química , Bacillus/enzimologia , Proteínas de Bactérias/metabolismo , Biotecnologia , Técnicas Eletroquímicas , Glucosiltransferases/metabolismo , Microscopia Eletrônica de Varredura , Nanopartículas/química , Tamanho da Partícula , Espectroscopia de Infravermelho com Transformada de Fourier , Suspensões , Água
15.
ScientificWorldJournal ; 2013: 948940, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24109209

RESUMO

Mixotrophic metabolism was evaluated as an option to augment the growth and lipid production of marine microalga Tetraselmis sp. FTC 209. In this study, a five-level three-factor central composite design (CCD) was implemented in order to enrich the W-30 algal growth medium. Response surface methodology (RSM) was employed to model the effect of three medium variables, that is, glucose (organic C source), NaNO3 (primary N source), and yeast extract (supplementary N, amino acids, and vitamins) on biomass concentration, X(max), and lipid yield, P(max)/X(max). RSM capability was also weighed against an artificial neural network (ANN) approach for predicting a composition that would result in maximum lipid productivity, Pr(lipid). A quadratic regression from RSM and a Levenberg-Marquardt trained ANN network composed of 10 hidden neurons eventually produced comparable results, albeit ANN formulation was observed to yield higher values of response outputs. Finalized glucose (24.05 g/L), NaNO3 (4.70 g/L), and yeast extract (0.93 g/L) concentration, affected an increase of X(max) to 12.38 g/L and lipid a accumulation of 195.77 mg/g dcw. This contributed to a lipid productivity of 173.11 mg/L per day in the course of two-week cultivation.


Assuntos
Aquicultura/métodos , Microalgas/metabolismo , Redes Neurais de Computação , Biomassa , Técnicas de Cultura de Células , Meios de Cultura/química , Glucose/química , Glucose/metabolismo , Metabolismo dos Lipídeos , Microalgas/crescimento & desenvolvimento , Modelos Biológicos , Nitratos/química , Nitratos/metabolismo , Análise de Regressão , Leveduras/metabolismo
16.
Bioresour Technol ; 142: 723-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23806510

RESUMO

An extractive bioconversion with Bacillus cereus cyclodextrin glycosyltransferase (CGTase, EC 2.4.1.19) in aqueous two-phase system (ATPS) was investigated for the synthesis and recovery of cyclodextrins (CDs). Optimum condition for the extractive bioconversion of CDs was achieved in ATPS consisted of 7.7% (w/w) polyethylene glycol (PEG) 20,000 and 10.3% (w/w) dextran T500 with volume ratio (VR) of 4.0. Enzymatic conversion of starch occurred mainly in dextran-rich bottom phase whereas the product, CDs was transferred to top phase and a higher partition coefficient of CDs was achieved. Repetitive batch of CDs synthesis was employed by replenishment of the top phase components and addition of starch every 8h. An average total CDs concentration of 13.7 mg/mL, (4.77 mg/mLα-CD, 5.02 mg/mLß-CD and 3.91 mg/mLγ-CD) was recovered in the top phase of PEG 20,000/dextran T500 ATPS. This study showed the effectiveness of ATPS application in extractive bioconversion of CDs synthesis with B. cereus CGTase.


Assuntos
Bacillus cereus/metabolismo , Ciclodextrinas/metabolismo , Glucosiltransferases/metabolismo , Água/química
17.
J Biomed Biotechnol ; 2012: 125865, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23133311

RESUMO

Factors influencing poly(3-hydroxybutyrate) P(3HB) production by Cupriavidus necator CCUG52238(T) utilizing oil palm frond (OPF) juice were clarified in this study. Effects of initial medium pH, agitation speed, and ammonium sulfate (NH(4))(2)SO(4) concentration on the production of P(3HB) were investigated in shake flasks experiments using OPF juice as the sole carbon source. The highest P(3HB) content was recorded at pH 7.0, agitation speed of 220 rpm, and (NH(4))(2)SO(4) concentration at 0.5 g/L. By culturing the wild-type strain of C. necator under the aforementioned conditions, the cell dry weight (CDW) and P(3HB) content obtained were 9.31 ± 0.13 g/L and 45 ± 1.5 wt.%, respectively. This accounted for 40% increment of P(3HB) content compared to the nonoptimized condition. In the meanwhile, the effect of dissolved oxygen tension (DOT) on P(3HB) production was investigated in a 2-L bioreactor. Highest CDW (11.37 g/L) and P(3HB) content (44 wt.%) were achieved when DOT level was set at 30%. P(3HB) produced from OPF juice had a tensile strength of 40 MPa and elongation at break of 8% demonstrated that P(3HB) produced from renewable and cheap carbon source is comparable to those produced from commercial substrate.


Assuntos
Cupriavidus necator/metabolismo , Hidroxibutiratos/metabolismo , Extratos Vegetais/metabolismo , Folhas de Planta/metabolismo , Óleos de Plantas/metabolismo , Poliésteres/metabolismo , Sulfato de Amônio/farmacologia , Biomassa , Reatores Biológicos/microbiologia , Cupriavidus necator/efeitos dos fármacos , Cupriavidus necator/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio/efeitos dos fármacos , Fenômenos Mecânicos/efeitos dos fármacos , Oxigênio/farmacologia , Óleo de Palmeira , Solubilidade , Temperatura , Fatores de Tempo
18.
Bioresour Technol ; 110: 566-71, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22342083

RESUMO

In this paper, we report that pressed juice from oil palm frond (OPF) contained renewable sugars such as glucose, sucrose and fructose. By using a simple sugarcane press, 50% (wt/wt) of OPF juice was obtained from fresh OPF. The glucose content in the juice was 53.95±2.86g/l, which accounts for 70% of the total free sugars. We have examined the effect of various OPF juice concentrations on the production of poly(3-hydroxybutyrate), P(3HB) by Cupriavidus necator CCUG 52238(T). The cell dry mass in shake flask experiment reached 8.42g/l, with 32wt.% of P(3HB) at 30% (v/v) of OPF juice, comparable with using technical grade sugars. The biopolymer had a molecular mass, M(w) of 812kDa, with a low polydispersity index of 1.61. This result indicates that OPF juice can be used as an alternative renewable carbon source for P(3HB) production and has potential as a renewable carbon source.


Assuntos
Carboidratos/isolamento & purificação , Eucalyptus/química , Fermentação , Carboidratos/química
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