Cross-linked lipase in hybrid matrix for biodiesel production from crude Jatropha curcas oil

Immobilization of lipases is gaining much attention these days due to the wide variety of reactions catalyzed by them. Moreover, the lipases play an important role in biodiesel production. In this study, lipase from Burkholderia cepacia was first cross-linked with glutaraldehyde followed by entrapment into hybrid matrix of equal proportions of alginate and β-carrageenan natural polymers. The immobilized lipase gave promising results with stability parameters like pH, temperature, solvent, storage, enzyme leakage, and hydrolytic activity. A significant reduction of 65.76% of enzyme leakage was obtained with this immobilized lipase. Moreover, a 100% yield of biodiesel was produced from crude Jatropha curcas oil using this immobilized lipase

Stability studies of immobilized Burkholderia cepacia lipase and its application in biodiesel production from Jatropha curcas Oil

This chapter focuses mainly on biodiesel production from the future green gold namely Jatropha curcas. The importance of this plant as biodiesel-feedstock, oil extraction methods from the seeds, and different routes of biodiesel production are discussed in the first part. Nowadays, immobilization of lipase has gained immense potential in the biofuel industry mainly to reduce the production costs and to make the method more economical. Different approaches of lipase immobilization are briefed in the second part. The final part of this chapter shows stability studies of Burkholderia cepacia lipase immobilized in hybrid matrix and its application and biodiesel optimization from crude J. curcas oil

Low-cost alternative renewable energy bioethanol production from palm oil in Malaysian context

Biofuels can be broadly defined as solids, liquids, or gas fuels consisting of, or derived from, plant biomass. Its use here is primarily with respect to a liquid transportation fuel (bioethanol or biodiesel). A major environmental issue being addressed by the global community is the sustainable supply of energy in parallel with a significant reduction in greenhouse gas emissions. This will be a significant technological and socioeconomic challenge because of our dependence on fossil fuel combustion for energy and the fact that it is this combustion that is the primary cause of greenhouse gas emissions

Quantitative assessment of seagrass as Bioethanol feedstock

The depletion of fossil fuels and the increase of fuel demand lead to the search of more sustainable alternatives. Nowadays, bioethanol is gaining popularity as renewable fuel to replace existing fossil gasoline. Currently, bioethanol is produced from land based crops but in the future, marine biomass such as seagrass and seaweeds are promising alternatives since these do not take up land area for cultivation. In this paper, seagrass, Thalassia hemprichii was tested for its potential as bioethanol feedstock via fermentation by yeast, Saccharomyces cerevisiae. Thalassia hemprichii is highly abundant as it can be easily cultivated in warm seawater in Malaysia for example in Sabah. Thalassia hemprichii contains high carbohydrate content, hemicellulose and cellulose which will be hydrolyzed to glucose and other reducing sugars, which in turn is converted to ethanol by yeast. It has been shown that the extracted leaves from Thalassia sp. through hot water treatment gives higher concentration of sugar (1.68g/ml) as compared to acid hydrolysis using dilute sulfuric acid (1.38g/ml). Besides that, among the five different inoculum concentrations, it was found that 10% (v/v) concentration of inoculum gives the highest bioethanol production for both types of treatments. Ethanol produced with hot water treatment (2.29g/ml) was higher as compared to sulfuric acid hydrolysis(1.74g/ml). The results from this study showed that Thalassia hemprichii has potential to be used as substrate for bioethanol production

Bioethanol production from galactose by immobilized wild-type Saccharomyces cerevisiae

Bioethanol has been emerging from different types of renewable feedstocks as an alternative to reduce problems caused by the use of fossil fuels. Galactose is the major sugar obtained from the hydrolysis of seaweeds and can be fermented to ethanol by yeast. Wild-type Saccharomyces cerevisiae has been reported with good performance of galactose fermentation. The first part of the study focused on the isolation and characterization of wild-type S. cerevisiae with the ability to ferment galactose to ethanol. A wild-type S. cerevisiae strain with the ability to ferment galactose to ethanol was isolated from grape with ethanol tolerance of 15%. Immobilization of yeast cells has been performed to increase the ethanol production. The second part of the study involved the immobilization of the isolated wild-type S. cerevisiae in PVA-alginate beads. Batch fermentation of galactose by immobilized wild-type S. cerevisiae obtained ethanol concentration and yield efficiency of 9.57?g/L and 93.82%. The immobilized wild-type S. cerevisiae were used for four cycles of galactose fermentation and obtained ethanol concentration of 7.66?g/L with yeast relative activity of 79.07%. In short, bioethanol produced by galactose fermenting wild-type S. cerevisiae can be a future sustainable fuel

Acetylcholinesterase (AChE) of Diodon hystrix brain as an alternative biomolecule in heavy metals biosensing

The continuous discharge of toxic materials into the environment has been an alarming issue faces around the globe. Hence, matching effort of monitoring activity is vital to coping with the overwhelming amount of metal ions. Along with the significant current research being conducted, this study aims to investigate the sensitivity of acetylcholinesterase (AChE) of Sabah porcupine fish, Diodon hystrix as an alternative biosensor in the detection of heavy metals. The enzyme was precipitated followed by the purification using ammonium sulfate precipitation and procainamide-affinity chromatography, respectively, with a total recovery of 66.67% with the specific activity of 2297.50 U/mg. The enzyme works optimally at pH 9 with the best incubation temperature of 30°C. The Michaelis constant (Km) and maximal velocity (Vmax) of 1.171 mM and 879257 mol/min/mg denotes the highest catalytic efficiency (Vmax/Km) of acetylthiocholine iodide (ATC) as its preferable substrate. Inhibition study tested on 10 metal ions resulted in increasing toxicity order of Cr6+ < Co2+ < Ag2+ < Cu2+ < Pb2+ < As5+ < Cd2+ < Zn2+ < Ni2+ < Hg2+, with only Hg2+ exhibited the half-maximal inhibitory concentration (IC50) of 0.48 mg/L. From the study, it suggests that the D. hystrix AChE as the potential conventional biosensor for heavy metals detection

Stability Studies of Immobilized Saccharomyces Cerevisiae in Calcium Alginate and Carrageenan Beads

Currently the resources for fossil fuels are depleting together with increase in fuel prices. This has urged the need for cheaper alternative fuels especially biofuels. The production of the most common liquid biofuel which is bioethanol using immobilized yeast cells is an approach taken to increase its demand in the world’s market. There are various methods for the immobilization of yeast cells; however before they can be applied in the industry the stability of the immobilization technology must be investigated. This research aims to study the stabilities of immobilized S. cerevisiae in calcium alginate and carrageenan beads for bioethanol production. The S. cerevisiae was immobilized in calcium alginate and carrageenan beads using entrapment method. Next, screening for the optimal concentration of sodium alginate and semi refined carrageenan matrices were determined by employing fermentation and bioethanol quantification using GC-MS. Concentrations of 2% (w/v) calcium alginate and 2% (w/v) semi refined carrageenan beads were identified to produce the highest bioethanol yield which were 0.286 g/mL and 0.065 g/mL respectively. The two beads were then chosen to be tested in various stability studies with respect to bioethanol production such as storage stability, reusability, pH, thermaland permeability test. It was found out that a concentration of 2% (w/v) calcium alginate beads were more stable as immobilization matrix for S. cerevisiae&nbsp; as compared to 2% (w/v) semi refined carrageenan

Oil palm empty fruit bunches as a promising feedstock for bioethanol production in Malaysia

Depletion of the fossil fuels together with an increase in energy demand is considered as a serious threat to the world. Furthermore, fuel versus food dilemma plays an important role in search of sustainable non-edible feedstocks for production of biofuels. Liquid biofuels such as bioethanol can pave way for a cleaner earth together with less dependency on fossil fuels. Empty fruit bunches (EFBs) is one of the potential biomass wastes, which can be utilized as a raw material for bioethanol production. The high availability of EFBs as a biowaste in Malaysia can endorse the concept of waste-to-wealth that had been long dreamed since late 1990, where unwanted wastes are converted into valuable energy. The three important steps in bioethanol production from EFBs, i.e. pretreatment, hydrolysis, and fermentation are discussed in this paper. This review paper highlights some available literature and detailed information regarding the EFBs as a potential feedstock for bioethanol production in Malaysia. An environmental-friendly bioenergy and zero waste can be anticipated in Malaysia which in turn promotes an economically sustainable bioethanol production. This review is vital as it explores the EFBs potential as a promising feedstock for bioethanol which can be implemented for future commercial purpose

Mixed anaerobic fermentation by clostridium and pseudomonas species

The selection of bacterial strains for the anaerobic fermentation if crucial since it determine fermentation performance and influences methods for feedstock pre-treatment, hydrolysis, and solvent recovery. The main bacterial strain used in anaerobic fermentation of ABE production is Clostridium species. However, the performance of wild-type Clostridium strains is limited by solvent tolerance and low cell density during the solventogenic phase of Clostridium growth and causes low production of solvent. So mixed cultures are proposed to overcome the mentioned drawbacks

Fuel ethanol production from papaya waste using immobilized Saccharomyces cerevisiae

Liquid biofuels such as bioethanol is gaining much interest as it can be produced from various biomass feedstocks. Papaya peels, one of the major agricultural waste in Malaysia has immense potential to be used as a promising bioethanol feedstock. Thus, the main objective of this research is to optimize the production of bioethanol from Carica papaya peels using immobilized yeast cells. At first, the papaya skin was dried and powdered prior to hydrolysis at 120°C for 15 minutes using 0.2 M H 2 SO 4 . Then Saccharomyces cerevisiae Type II strain was immobilized using 12% polyvinyl alcohol and 1% sodium alginate using entrapment technique. These immobilized beads were later employed for the production of bioethanol from dried papaya peels. Most significant parameters such as temperature, agitation speed, pH and fermentation time were optimized by employing batch fermentation and bioethanol produced was quantified using Gas Chromatography-Mass Spectrometry. A bioethanol yield of 0.514 g/L was obtained from papaya peels at the optimized conditions of 30°C, 200 rpm, pH 5 and 48 h of fermentation. In short, since the sugars can be easily released from papaya skin, this can be considered as a potential feedstock for bioethanol