Abu Yousuf | University Malaysia Pahang (original) (raw)

Papers by Abu Yousuf

World Academy of Science, Engineering and Technology, International Journal of Energy and Power Engineering, 2017

2019 IEEE Intl Conf on Dependable, Autonomic and Secure Computing, Intl Conf on Pervasive Intelligence and Computing, Intl Conf on Cloud and Big Data Computing, Intl Conf on Cyber Science and Technology Congress (DASC/PiCom/CBDCom/CyberSciTech)

The worldwide concern to mitigate the soaring energy crisis introduces us to the small-scale rene... more The worldwide concern to mitigate the soaring energy crisis introduces us to the small-scale renewable energy generation as a preferred enabling source for highway lighting. However, the extensive cost and performance inconsistency of the pure solar panel based solutions further motivate efforts in designing a hybrid energy solution for highway lighting in which Internet of Things (IoT) is envisioned to play a pivotal role in controlling multiple energy sources to provide an effective environment for such a smallscale application context. This paper proposes an IoT-enabled intra-network solution to organize the energy sources for improving the battery performance in a hybrid energy driven highway lighting system. More specifically, we consider the solar panel and Vertical Axis Wind Turbine (VAWT), which utilizes energy from the aerodynamic losses produced by vehicles in the highways, as two main sources for energy generation. This hybrid system allows for generating uninterrupted energy by solar during the day and by VAWT at all day and night times whenever a vehicle passes the lamppost. For maximum effectiveness, a micro-controller is employed in this system to sense the internal requirements for utmost performance. A test-bed prototype is developed to evaluate the performance of the proposed system over a pure solar based lighting system via a projected cost analysis. The result demonstrates withdrawal of solar dependency followed by a less energy requirement in the hybrid lighting system according to different busyness level of the highway.

The oleaginous yeasts Lipomyces starkey were grown in the presence of dairy industry wastewaters ... more The oleaginous yeasts Lipomyces starkey were grown in the presence of dairy industry wastewaters (DIW). The yeasts were able to degrade the organic components of DIW and to produce a significant fraction of their biomass as triglycerides. When using DIW from the Ricotta cheese production or residual whey as growth medium, the L. starkey could be cultured without dilution nor external organic supplement. On the contrary, the yeasts could only partially degrade the DIW from the Mozzarella cheese production, due to the accumulation of a metabolic product beyond the threshold of toxicity. In this case, a dilution of the DIW was required to obtain a more efficient degradation of the carbon compounds and an higher yield in oleaginous biomass. The fatty acid distribution of the microbial oils obtained showed a prevalence of oleic acid, and is compatible with the production of a II generation biodiesel offering a good resistance to oxidation as well as an excellent cold-performance.

International Review of Biophysical Chemistry, 2014

Microbial lipids are considered as a promising and sustainable feedstock for biodiesel production... more Microbial lipids are considered as a promising and sustainable feedstock for biodiesel production due to their fatty acid composition similar to that of vegetable oils. So far, microalgae have attracted more attention as a lipid producer in comparison to other non-photosynthetic oleaginous microbes. Nevertheless, recent studies showed the efficiency of other microorganisms, including bacteria, yeasts, molds which are able to accumulate lipids over 20 % of their dry biomass. Competence of lipid production by those photosynthetic and non-photosynthetic microbes are highly depend on the cost of reactor design, wide range of nutritional substrates, scalability, parasitic energy demand, metabolic function etc. Therefore, integration of biology and engineering is essential for a cost-effective production of microbial lipids. This paper compares microalgae and non-photosynthetic microbes as regards the factors affecting the techno-economical feasibility of the microbial oil production.

Environmental Engineering and Management Journal, 2017

In this study, the oleaginous yeasts cultured in tomato waste hydrolysates (TWH) to produce micro... more In this study, the oleaginous yeasts cultured in tomato waste hydrolysates (TWH) to produce microbial lipids that offer a suitable alternative to vegetable oils as feedstock for the biodiesel synthesis. The TWH were prepared by acid hydrolysis (2.5% H2SO4). To obtain higher growth rates, as well as higher lipid contents, Lipomyces starkeyi were cultured under original nitrogen content (TWHON), lower nitrogen content (TWHLN), attained by alkaline precipitation of TWHON followed by centrifugation and filtration, and higher nitrogen content (TWHHN), prepared by addition of (NH4)2SO4. To reduce the effect of the inhibitors of the microbial growth (acetic acid, furfural etc.) generated during the acid hydrolysis of tomato waste, the hydrolysates were preliminary diluted. However, the highest values of microbial growth and biomass yield were observed when using undiluted medium with lower nitrogen content. The addition of a N source to the medium had no significant effect on the growth rate of the yeasts, as well as on lipid accumulation. The distribution of fatty acids in microbial lipids was almost similar to that of plant oils. Consequently, these lipids can be used to synthesize a biodiesel offering excellent performances as automotive fuel.

IIUM Engineering Journal, 2017

Microbial fuel cell (MFC) is a bioelectrochemical system that uses bacteria as biocatalyst to oxi... more Microbial fuel cell (MFC) is a bioelectrochemical system that uses bacteria as biocatalyst to oxidize organic substrates as well as release electrons, which can be harvested in an external circuit to produce electrical energy. In this study, a proteolytic biocatalyst Bacillus cereus (B. cereus) has been employed for the first time in a microbial fuel cell (MFC). The wild type pure culture was isolated from municipal wastewater and identified using Biolog Gen III analysis. The MFCs were fueled with palm oil mill effluent (POME) and attained the maximum power density of about 3.88 W/m3. The electrochemical behavior of MFC operated by B. cereus was evaluated using polarization curve, electrochemical impedance spectroscopy (EIS) and cyclic voltammetery (CV) analysis. B. Cereus excreated electron shuttling compound which significantly reduced the anode charge transfer resistance (52.95%). The FESEM result shows that B. Cereus has the capability of effective biofilm formation. These resul...

ACS Sustainable Chemistry & Engineering, 2018

The interspecies interactions in microbial communities are very complex, rendering identification... more The interspecies interactions in microbial communities are very complex, rendering identification of synergistic or antagonistic relationships very difficult; however, understanding the mutualistic relationship between the microbes is exigent to gain deeper insight into their performance in wastewater fed microbial fuel cells (MFCs). In the present study, we aimed to explore the ecological networks between the microorganisms in a defined coculture system comprising with Pseudomonas aeruginosa (P. aeruginosa) and Klebsiella variicola (K. variicola). The coculture showed around 3 times higher current density in MFCs compared with either of these two bacteria alone. Metabolite analysis demonstrated that the fermentative metabolite (1,3-propanediol) produced by K. variicola stimulated the P. aeruginosa to produce a higher amount of pyocyanin through synergistic interactions, leading to the enhancement in the performance of coculture MFCs fed with palm oil mill effluent (POME). This study proves that the metabolite based "interspecies ecological communicatio" can enhance the electrochemical activity in MFCs.

Biotechnology progress, Jan 21, 2018

The aim of the study was to investigate the feasibility of using irreversible electroporation (EP... more The aim of the study was to investigate the feasibility of using irreversible electroporation (EP) as a microbial cell disruption technique to extract intracellular lipid within short time and in an eco-friendly manner. An EP circuit was designed and fabricated to obtain 4 kV with frequency of 100 Hz of square waves. The yeast cells of Lipomyces starkeyi (L. starkeyi) were treated by EP for 2-10 min where the distance between electrodes was maintained at 2, 4 and 6 cm. Colony forming units (CFU) were counted to observe the cell viability under the high voltage electric field. The forces of the pulsing electric field caused significant damage to the cell wall of L. starkeyi and the disruption of microbial cells was visualized by field emission scanning electron microscopic (FESEM) image. After breaking the cell wall, lipid was extracted and measured to assess the efficiency of EP over other techniques. The extent of cell inactivation was up to 95% when the electrodes were placed at t...

Journal of Physics: Conference Series, 2017

This paper presents a mathematical model and solution strategy of ethanol fermentation for oil pa... more This paper presents a mathematical model and solution strategy of ethanol fermentation for oil palm trunk (OPT) sap by considering the effect of substrate limitation, substrate inhibition product inhibition and cell death. To investigate the effect of cell death rate on the fermentation process we extended and improved the current mathematical model. The kinetic parameters of the model were determined by nonlinear regression using maximum likelihood function. The temporal profiles of sugar, cell and ethanol concentrations were modelled by a set of ordinary differential equations, which were solved numerically by the 4th order Runge-Kutta method. The model was validated by the experimental data and the agreement between the model and experimental results demonstrates that the model is reasonable for prediction of the dynamic behaviour of the fermentation process.

Energy & Fuels, 2017

Mutual interactions between microorganisms play a vital role in the formation ofelectroactive bio... more Mutual interactions between microorganisms play a vital role in the formation ofelectroactive biofilms, which is a key element in the longevity and suca.ss of bioelectrochemical S}"Stems. The present study was intended to examine both the electrogenic properties of B. cereus and its ability to inhibit methanogenesis in microbial fuel ceUs (M FCs). The potential influence of the incorporation of B. cereus into anaerobic sludge (AS) on the electrochemical activity was assessed using cydic voltammetry (CV) and electrochemical impedana. spectroscopy {EIS) analyses. The CV of M FCs with B. ""'""' showed a strong redox peak, suggesting that B. cereus has electrogenetic properties. Moreover, the incorporation of B. cereus inlo AS provided an enhancement in the power generation (4.83 \V / ml) and the CE (22%) of the M FC compared to the corresponding values for an M FC inoculated solely with AS (l.82 \V / ml, 12%). The increase in power generation could be due to the antimethanogenic property of B. cereus, which was evident from the 54% reduction in methane production. The results of this study suggest that the incorporation of microorganisms with electrogenic and antimethanogenic properties into AS promotes the formation of electroactive biofilms and maxini rzes the power generation of MFCs by suppressing the methanogenesis.

RSC Advances, 2017

Simultaneous power generation and wastewater treatment in the single chamber air cathode microbia... more Simultaneous power generation and wastewater treatment in the single chamber air cathode microbial fuel cell have been enhanced by introducing wild-type Klebsiella variicola as an efficient inoculum for the anode operated with palm oil mill effluent.

Waste Biomass Management – A Holistic Approach, 2017

Biotechnology Letters, 2016

Microbial oils are considered as alternative to vegetable oils or animal fats as biodiesel feedst... more Microbial oils are considered as alternative to vegetable oils or animal fats as biodiesel feedstock. Microalgae and oleaginous yeast are the main candidates of microbial oil producers' community. However, biodiesel synthesis from these sources is associated with high cost and process complexity. The traditional transesterification method includes several steps such as biomass drying, cell disruption, oil extraction and solvent recovery. Therefore, direct transesterification or in situ transesterification, which combines all the steps in a single reactor, has been suggested to make the process cost effective. Nevertheless, the process is not applicable for large-scale biodiesel production having some difficulties such as high water content of biomass that makes the reaction rate slower and hurdles of cell disruption makes the efficiency of oil extraction lower. Additionally, it requires high heating energy in the solvent extraction and recovery stage. To resolve these difficulties, this review suggests the application of antimicrobial peptides and high electric fields to foster the microbial cell wall disruption.

MATEC Web of Conferences, 2016

This study is aimed to evaluate the electricity generation from microbial fuel cell (MFC) and to ... more This study is aimed to evaluate the electricity generation from microbial fuel cell (MFC) and to analyze the microbial community structure of city wastewater and anaerobic sludge to enhance the MFC performance. MFCs, enriched with palm oil mill effluent (POME) were employed to harvest electricity by innoculating of Klebsiella oxytoca, collected from city wastewater and other microbes from anaerobic sludge (AS). The MFC showed maximum power density of 207.28 mW/m 3 with continuous feeding of POME using microbes from AS. Subsequent replacement with Klebsiella oxytoca resulted maximum power density of 1236 mW/m 3 by utilizing complex substrate POME which was six times higher as compared to MFC operated with AS. Based on Biolog gene III analysis, relatively higher abundance of Klebsiella oxytoca was detected in the city wastewater. Predominant microorganisms such as Gammaproteobacteria, Azospiraoryzae, Acetobacterperoxydans and Solimonasvariicoloris were isolated from palm oil anaerobic sludge as well as from biofilm of MFC. Enriched electrochemically active bacteria Klebsiella oxytoca showed better performance to generate electricity from complex POME substrates compare to AS. These results demonstrate that the power output of MFCs can be increased significantly using Klebsiella oxytoca. 4 4 This is an Open Access article distributed under the terms of the Creative Commons Attribution License 4.0, which permits distribution, and reproduction in any medium, provided the original work is properly cited.

Asian Journal of Medical and Biological Research, 2015

Ground nut is one of the commonly used decorative nutritious relish seed around the world. Ground... more Ground nut is one of the commonly used decorative nutritious relish seed around the world. Ground nut have hypocholesterolamic, hypoglycemic, hypolipidemic, anti-atherosclerotic, immune-modulatory and bacterial counting effects. In Bangladesh, limited research has so far been performed on the action of ground nut in biological system and its comparative efficacy with commercialized drugs that reduce blood cholesterol. The aim of this study was carried on the effects of PUFA on blood total cholesterol (TC), high density lipoprotein (HDL), low density lipoprotein (LDL) and triglyceride (TG) and against artificial inoculation (I/N) Staphylococcus aureus infection of experimental rat by feeding of ground nut. A total of fifteen long Evans rats (Rattus norvegicus) were used for this study. The rats were randomly divided into three equal groups (n=5) and numbered as A, B and C. Group A (control), Group B (50gm ground nut/ day/group), group C (100 gm ground nut/day/group). All groups were supplied with standard broiler pellet and fresh drinking water throughout the experimental period (January to June /2012). The blood samples were collected directly from the heart at the 1 st and 60 th day for biochemical test (TC, LDL, HDL and TG) and test was performed as per Memorial Diagnostic Centre, Charpara, Mymensingh. Staphylococcus aureus was cultured in nutrient broth and 100 l of their culture was inoculated into the rats through intranasal route. Among all the treated groups, the rats of group C exhibited the lowest TC value, TG and LDL and reduced blood cholesterol significantly than (control group A) followed by group B. In bacteriological examinations, it was found that the number of bacterial colony lowest in group C in comparison with the group of A and B. From the present experiment, it can be assumed that PUFA has significant effect on blood lipid profile and against bacterial infection.

Chemical Engineering Transactions

Lignocellulosic wastes from Arundo donax (AR) and Sorghum bicolor (SB) were used as a source of f... more Lignocellulosic wastes from Arundo donax (AR) and Sorghum bicolor (SB) were used as a source of fermentable sugars for culturing the oleaginous yeasts Lipomyces starkey. In order to minimize the generation of inhibitors of the microbial growth, that is a serious bottleneck still limiting the industrial production of microbial oils, the lignocellulosic materials were first steam-exploded and subsequently treated with commercial preparations of cellulases and β-glucosidases. This treatment made possible the growth of yeasts in the presence of raw hydrolysates, thus improving the production of microbial oils from oleaginous yeasts, potentially allowing a sustainable production of IIgeneration biodiesel. The conditions of the hydrolysis of the AD and SB, as well as the conditions of the fermentation of the hydrolysates, were optimized in order to maximize both the microbial biomass yield and the lipid fraction of the biomass. The composition of the triglycerides obtained adopting such conditions were compatible with the production of a good-quality automotive biodiesel.

Catalysis Science & Technology, 2015

The article reviews the mechanism, how Schottky barrier and the SPR phenomena help to improve a p... more The article reviews the mechanism, how Schottky barrier and the SPR phenomena help to improve a photoreaction, focusing on the paradox between the Schottky barrier and SPR in the matter of the way of electron flow in the metal/semiconductor system.

2014 3rd International Conference on the Developments in Renewable Energy Technology (ICDRET), 2014

Agriculture, apart from crops and livestock, is a source of large amounts of troublesome by like ... more Agriculture, apart from crops and livestock, is a source of large amounts of troublesome by like different kinds of manure. Nevertheless, they could be successfully processed through anaerobic digestion technology, which allows for waste utilization and energy generation. Production of biogas from manure only is low efficient due to the low dry matter content (about 8%). The additional substrates, such as plants with high dry mass content, are used to improve the process efficiency. In this work biogas production technologies from different agricultural as well as horticultural feedstock was used along with the pretreatment w cellulose degrading bacteria, a comparative experimental analysis between different types of biomass residues used for biogas production estimation of biological oxygen demand chemical oxygen demand (COD), cellulose, pH, Nitrogen, Phosphorus and Potassium anaerobic fermentation process. The comparison is achieved using as parameter the biogas quality and quantity which are produced, using different available agricultural and horticultural waste material. measurements were made on a lab scale pilot installation.

Procedia Engineering, 2014

Kitchen waste (KW) can be utilized to produce biogas due to its high biodegradability, calorific ... more Kitchen waste (KW) can be utilized to produce biogas due to its high biodegradability, calorific value and nutritive value to microbes, which will reduce our dependency on fossil fuels. The research work was conducted to investigate the production ability of biogas as an alternative energy from KW with co-digestion of cow manure (CM) through anaerobic digestion (AD). Firstly, three digesters were prepared to observe the individual degradation rate of KW, CM and co-digested KW with CM at room temperature (25°C~30° C) and at temperature of 37°C (mesophilic digestion) respectively and observed the degradation rate for co-digested KW with CM was higher than KW and CM alone. Secondly, three digesters were constructed to observe the effect of alkalinity at temperature 37° C and loading rate 200 gm/L. Three alkali (NaOH) doses 1.0%, 1.5% and 2.0% on wet matter basis of kitchen waste were applied to improve biodegradability and biogas production. The highest degradation rate was 6.8 ml/gm which was obtained from 1.5% NaOH and also observed that biogas production was almost doubled from treated KW than untreated KW. Finally, a portable biogas reactor was fabricated for pilot-scale biogas production which included an agitator and heating system. This reactor was operated at both 37° C and room temperature at a loading rate of 200 gm/L and observed that the digestion rate was faster at 37°C than room temperature. The prime object of this work was to investigate the prospect of kitchen waste for biogas production and ultimate protection of environment from the bad effect of methane gas that would be produced by uncontrolled anaerobic digestion.

Fuel, 2014

h i g h l i g h t s Catalyst CuO/C was prepared by a novel technique where activated carbon was i... more h i g h l i g h t s Catalyst CuO/C was prepared by a novel technique where activated carbon was introduced with nano-sol. The free fatty acid conversion was achieved up to 95% using 8 wt% catalysts. High catalytic activity was observed and activity was lost about 20% after four cycles uses.