63 research outputs found
The development of kit system for honey quality quick check from different species of stingless bee honey in Malaysia
No full textStingless bee is a large group of bees in family Apidae that have the ability to produce different types of products that valuable to humankind which are honey, bee bread, and propolis. The growing demand for honey in the market has led to the occurrence of the tampering honey with foreign substances and increases the production of artificial honey. There are lots of laboratory tests for honey adulteration however most of tests are tedious, high cost and complicated. Therefore, there should be a continuously development and testing of alternative methods that would allow faster and easier detection of honey adulteration. This research attempt to develop a simple inexpensive paper-based amperometric biosensor based on Prussian Blue (PB)-modified screen-printed carbon electrodes (SPCEs). To do so, cellulose filter paper was used as immobilization matrix for glucose oxidase (GOx), invertase (INV) and hydrogen peroxidase (HRP) as it was successfully embedded within the fibre matrix of paper via physical adsorption. The paper-based biosensor allowed a small amount (8 μL) of sample solution for both glucose sucrose analysis. The glucose biosensor had a linear calibration range between 0.5 mM to 4.5 mM (R2= 0.9925) and a detection limit of 0.15 mM. For sucrose biosensor the calibration ranges from 0.1 mM to 1.1 mM (R2=0.9897) and detection limit of 0.1 mM. Interference study of selected potential interfering compounds on the biosensor response was investigated. In addition, its performance was demonstrated in the analysis of six honey samples. The results obtained using glucose biosensor corroborated well with high performance liquid chromatographic (HPLC) method however for sucrose biosensor, more study should be done to improve the result obtained as it has more than 70% differences with reference. From this research, it can be concluded that, the prototype sensor to determine sugar adulteration in stingless bee honey was successfully developed
Waste to wealth project with Mercu Resolution
No full textWaste generation involves serious environmental pollution and degradation which consequently increased the environmental costs for its collection, treatment and disposal. Thus, the call for environmentally and economically sustainable growth is set out loud and simple. The present and future generations must therefore ensure that all resources are conserved, fully utilized and well managed. Various waste has been explored in this research such as municipal solid waste, fish waste and food waste. These wastes were utilized to become valuable resources and at the same time to reduce waste production. A total of seven studies have been done including biological degradation of municipal solid waste using mixed culture, production of biofertilizer using landfill leachate, oil extraction for a production of fatty acid from fish waste, fish feed production from fish waste, process simulation of anaerobic digestion process for biogas production from food waste, adsorbent from landfill sludge and finally, microwave irradiation and wet rendering to improve torrefaction of food waste. In conclusion, this research has successfully turned waste into wealth which later can be used for better future
Kinetic correlations of gas-liquid mass transfer coefficient and oxygen uptake rate of heterologous protein cultivation by sonobioreactor
No full textSonobioreactor in this study is an integration system which includes the use of a sonicator with a bioreactor by the assembly of a peristaltic pump. The sonobioreactor was being applied to the production of a heterologous protein, lipase by the expression of a recombinant E. coli. The first objective of this study was to transform all the recombinant E. coli into BL21 host. The BL21 was found successful in carrying pTrcHis and pUC8, both carrying lipase gene from Staphylococcus hyicus and Rhizopus oryzae, respectively. Second objective is to investigate the characteristics of 2-L sonobioreactor for the use of recombinant E. coli cultivation. The sonobioreactor has shown some improvement of gas-liquid transfer (kLa} compared to the standalone system. Third objective is to determine the expression of lipase and plasmid stability of recombinant E. coli under sonicated and non-sonicated ultrasound regimens. The non-sonicated cultivation has shown higher lipase activity compared to the sonicated cultivation. The gradual sonication duty cycle has shown images of deformed cells of recombinant E. coli at 9K total magnification via SEM. Performances and kinetics of bioprocesses outcomes in this study may contribute to the current modelling of E. coli fermentations, especially for the recombinant protein production
Cadangan awal : perlaksanaan cleaner production (CP) dan promosinya kepada industri pemprosesan nenas
No full textHigh gravity extractive fermentation for enhanced productivity of bioethanol : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Biochemical Engineering at Massey University, Palmerston North, New Zealand
No full textBioethanol is a renewable alcohol fuel produced from sugary substrates via fermentation
processes. Accumulation of ethanol in the fermentation broth inhibits cell growth and
further production of ethanol. Recovering ethanol from a dilute broth is expensive.
Ethanol inhibition of fermentation may be reduced by continuously removing it as it is
formed.
This work focussed on production of bioethanol from glucose using the anaerobic
bacterium Zymomonas anaerobia. This bacterium produces ethanol more rapidly than
does the conventional yeast fermentation. The aim was to assess the impact of continuous
in-situ removal of ethanol on the productivity of batch and continuous high-gravity
fermentations. High-gravity fermentations use a medium with a high concentration of
sugar to reduce production volume (bioreactor size) and potentially achieve a high
productivity of ethanol, if the ethanol concentration in the broth can be kept to below
inhibitory levels.
First, the batch fermentation was characterized for glucose tolerance, ethanol
tolerance, optimal production temperature and biocompatibility with solvents and
adsorbents that could be used for in-situ removal of ethanol. High gravity media
containing 50–300 g L-1 glucose were used to characterize batch and continuous
fermentations with a view to identifying the best fermentation conditions for a detailed
study. The optimal fermentation temperature was found to be 35 [deg]C and the maximum
tolerable initial glucose (i.e. without causing substrate inhibition) was 150 g L−1.
In continuous high-gravity fermentations, six different dilution rates (D = 0.05–
0.30 h-1) were tested, but steady-state operation proved to be impossible at the lowest
dilution rate: the fermentation showed a highly consistent oscillatory behaviour that was
ascribed to ethanol toxicity. Use of higher dilution rates could overcome oscillations by
washing out the ethanol from the bioreactor, but this reduced ethanol productivity as
glucose and biomass also washed out. Strategies for removing ethanol in-situ while
operating at such a dilution rate as to achieve a high ethanol productivity, were assessed
by using liquid-liquid extraction and adsorption on polymer resins as methods for
removing ethanol as it was being produced.
High gravity extractive fermentation for enhanced productivity of bioethanol
In the absence of in-situ removal of ethanol, the lowest operable steady-state
dilution rate (i.e. without oscillations) was 0.15 h-1. With in-situ removal of ethanol, the
dilution rate for stable steady state operation could be reduced to 0.05 h-1. At a dilution
rate of 0.15 h-1, the steady-state ethanol concentration was 42.5 g L-1 and the biomass
concentration was 1.49 g L-1. In the absence of in-situ ethanol removal, the ethanol
concentration, but not ethanol productivity, was highest at a dilution rate of 0.3 h-1
although much residual glucose remained.
In in-situ batch extractive fermentations, all extraction solvents tested improved
biomass concentration, glucose consumption and ethanol concentration relative to
control, but iso-octadecanol was clearly the most effective solvent. For batch in-situ
extractive fermentation with iso-octadecanol, the ethanol yield on glucose was
0.485±0.005 g g-1, or comparable to to a yield of 0.468±0.005 g g-1 for the control
culture, but the ethanol productivity was distinctly higher than for the control culture. Of
the various polymer resins tested in batch fermentations for in-situ removal of ethanol by
adsorption, Dowex Optipore L-493 appeared to be somewhat better than the control (i.e.
no resin).
The best extraction solvent (i.e. iso-octadecanol) and the best adsorption resin (i.e.
Dowex Optipore L-493) were separately assessed for ethanol removal in continuous
fermentations. Continuous removal of ethanol both by adsorption and solvent extraction
allowed a steady-state operation of the continuous fermentations at a dilution rate of 0.05
h−1 — the dilution rate at which steady-state operation had proved impossible in control
fermentation (i.e. without in-situ removal of ethanol). This confirmed the mechanism
used to explain the oscillatory behaviour of the fermentation and showed that in-situ
ethanol removal permitted steady-state operation at dilution rates that would not allow
such operation in the absence of ethanol removal. At a dilution rate of 0.05 h−1, an
extraction solvent flow rate of 300 mL h−1 provided the highest total ethanol productivity
and ethanol yield on glucose while keeping the solvent use to a minimum
Ultrasound mediated enzymatic hydrolysis of cellulose and carboxymethyl cellulose
No full textA recombinant Trichoderma reesei cellulase was used for the ultrasound‐mediated hydrolysis of soluble carboxymethyl cellulose (CMC) and insoluble cellulose of various particle sizes. The hydrolysis was carried out at low intensity sonication (2.4–11.8 W cm−2 sonication power at the tip of the sonotrode) using 10, 20, and 40% duty cycles. [A duty cycle of 10%, for example, was obtained by sonicating for 1 s followed by a rest period (no sonication) of 9 s.] The reaction pH and temperature were always 4.8 and 50°C, respectively. In all cases, sonication enhanced the rate of hydrolysis relative to nonsonicated controls. The hydrolysis of CMC was characterized by Michaelis‐Menten kinetics. The Michaelis‐Menten parameter of the maximum reaction rate Vmax was enhanced by sonication relative to controls, but the value of the saturation constant Km was reduced. The optimal sonication conditions were found to be a 10% duty cycle and a power intensity of 11.8 W cm−2. Under these conditions, the maximum rate of hydrolysis of soluble CMC was nearly double relative to control. In the hydrolysis of cellulose, an increasing particle size reduced the rate of hydrolysis. At any fixed particle size, sonication at a 10% duty cycle and 11.8 W cm−2 power intensity improved the rate of hydrolysis relative to control. Under the above mentioned optimal sonication conditions, the enzyme lost about 20% of its initial activity in 20 min. Sonication was useful in accelerating the enzyme catalyzed saccharification of cellulose
Production of Bioethanol by Zymomonas Mobilis in High-gravity Extractive Fermentations
No full textContinuous removal of ethanol during production by the anaerobic bacterium Zymomonas mobilis mitigated ethanol inhibition. Ethanol inhibited its own production at a concentration of >20 g L−1. Ethanol productivity was enhanced by continuous in situ extraction with water-immiscible organic solvents. Several solvents were evaluated for biocompatibility with Z. mobilis and the ability to extract ethanol from a batch fermentation. In situ batch extractive fermentations were carried out in a 2-L stirred bioreactor (1:1 volume ratio of solvent and fermentation broth) with an optimal glucose concentration of 150 g L−1, 35 °C, and an agitation speed of 150 rpm. Oleyl alcohol, iso-octadecanol and 2-octyl-1-dodecanol were the three solvents that were most compatible with Z. mobilis. With these solvents, the cell viability relative to control (no solvent) was 1.48 ± 0.40, 1.03 ± 0.18 and 1.05 ± 0.07, respectively, after two days of exposure. All solvents tested improved the final biomass concentration, the glucose consumption and ethanol production relative to control, but iso-octadecanol was clearly the most effective solvent. Using iso-octadecanol, the maximum ethanol concentration of 75 ± 3 g L−1 was attained. This was nearly 1.25-fold that of the control fermentation. For this solvent, the ethanol yield on glucose was 0.485 ± 0.005 g g−1 compared to a yield of 0.468 ± 0.005 g g−1 for the control culture
Biological cyanide treatment of petrochemical industry wastewater via bioremediation process
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