Scaling up the production of myco-coagulant using solid-state fermentation for water treatment

Aims@#Providing safe drinking water is an ongoing global concern. Coagulation is an essential process in water treatment. However, most of the coagulants are chemical in nature and have negative impacts on human health and the environment. This study investigated the production of myco-coagulant in solid-state fermentation using a fungal strain. @*Methodology and results@#A scale-up was performed using the tray method to investigate the influence of substrate thickness (from 2-30 mm) on myco-coagulant production. The results revealed that the turbidity removal efficiency of myco-coagulant in kaolin suspension was found to be increasing with the increase in thickness of the coco peat substrate. However, the myco-coagulant extracted from the media with a thickness of 30 mm was able to remove the highest turbidity by 96%. Three different subculturing methods for mycelium inoculation were evaluated. The surface inoculation approach produced better results than other inoculation processes. The effect of initial turbidity values (50-300 NTU) on turbidity removal was studied too. The myco-coagulant was found to be the most suitable for high-turbidity water (300 NTU) with turbidity removal of 52%. Subculturing of fungus from solid-state to solid-state was also studied, which showed that the strategy was just as effective as an inoculum-based subculture. @*Conclusion, significance and impact of study@#Excellent bio-coagulation activity has been shown for the myco-coagulant that was isolated from the fungus strain. Subculturing using existing substrates will be more economical than subculturing using fresh inoculum. This strategy saves time, labour and cost of the coagulant production.

A new isolate of thermophilic and organic solvent tolerant bacteria for lipase production using basal medium of palm kernel cake 80-87

@#Aims: This research focused on the selection of potential strains especially bacteria that can grow effectively in palm kernel cake (PKC) and produce high amount of thermostable and solvent tolerant (TS-OST) lipase. The work involved the exploration of renewable PKC as potential fermentation medium for discovery to novel TS-OST lipase that would have excellent tolerance and activity in presence of organic solvents with high temperatures for industrial applications.Methodology and results: Using palm kernel cake (PKC) as source of thermophilic bacteria, 53 bacterial strains were found survived at temperature 65 °C. However, after subcultured several times, only 17 strains were found as pure thermophilic strains. Preliminary screening both qualitative and quantitative was performed to all 17 potential thermophilic bacterial strains and showed that only 11 purified thermophilic strains are lipase producer. Strain PKC-P1 produced highest enzyme activity (11.13 U/g), followed by PKC-P13 and PKC-C9. The lowest enzymeactivity was lipase produced byPKC-C10 (0.76U/g). Strain PKC-P1 has been classified as Gram negative bacteria and identified as Bacillus smithiistrain PKC_P1.Conclusion, significance and impact of study: PKC as a by-product of oil palm industry consistsof many nutrients that can give benefits towards industry and can be utilized in order to produce enzymes like lipases. From these results, it could be concluded that this lipase stable at temperature 65 °C and pH 7 and may be a potential candidate to be used in a variety of biotechnological applications. This finding revealed that a bacterial strain obtained from oil-rich environment which is PKC through isolation process has potential as a source of more economical enzyme to be applied in biotechnology industr

Isolation and screening of bacteria with biofilm formation ability and characterization with hydrolytic enzyme production for enhanced biogas production 96-101

@#Aims: Biofilm is a complex structure that provides protection towards the bacteria within the barrier. Enhanced biogas production from Palm Oil Mill Effluent (POME) can be achieved by applying biofilm based anaerobic digestion system.Methodology and results:Bacteria that produces biofilm were isolated and tested on its hydrolytic enzyme secretion. The biofilm produced were also characterized. Out of 120 strains isolated from POME, PKC and food waste compost, only 33 strains were producing biofilm and only 11 of them exhibited significant amount of biofilm produced at optical density of wavelength 595 nm (>0.01). In hydrolysis enzyme assay test, all strains were not able to secrete protease enzyme. The biofilms were extracted and characterized to show similar characteristic for all strains. Strain numbers of 11, 9C, 23C and 30C showed positive result for cellulase, amylase and lipase enzymes, to be tested as single strain bacteria and also mixed with other isolated bacterium for prospect research on effective hydrolysis towards enhanced biogas production. The composition of biofilms from different bacteria mixture also similar under the same incubation condition.Conclusion, significance and impact of study: Bacteria producing biofilm are very limited and does not secrete the same hydrolytic enzymes. Utilization of these bacteria may eliminate the problem of microbial instability in a system.

Immobilization of fungal biomass with multi-walled carbon nanotubes as biosorbent

@#Aim:This study was mainly highlighted on a combination of fungal biomass onto MWCNTs in order to enhance the positive integration of impurities removal in aqueous solution. Methodologyand results:The immobilization of fungal biomass and MWCNTs was done in a batch liquid medium with several factors such as agitation speed, dose of MWCNTs, pH and inoculum dosage that were conducted with one factor at one time (OFAT) method. Basically, to verify the functional group of MWCNTs, Aspergillusnigerbiomass and immobilized A. nigerbiomass, the FTIR was applied and FESEM was done to demonstrate andcompare the image of the immobilized A. nigerbiomass with MWCNTs and fungal biomass alone. The finding showed the best agitation speed, dose of MWCNTs, pH and inoculum dosage were 150 rpm, 0.5 g, 5-6 and 2% respectively. FTIR indicates the presents of the functional groups like –OH (3270 cm-1), C-O (1619 cm-1) and –CH (2915 cm-1) while FESEM illustrates the images of the wrapped MWCNTs on A. nigerbiomass. Conclusion, significance and impact of study:The conventional technique of adsorption of fungal biomass alone not showing a favorable removal of impurities. Thus, the immobilization of fungal biomass (A. niger) with multi-walled carbon nanotubes (MWCNTs) was a good combination since both have potential functional group to accumulate to each other and has a tendency to remove effectively and efficiently the impurities in aqueous solution.