Abstract: Approximately 10,000 different types of dyes and
pigments are being used in various industrial applications yearly,
which include the textile and printing industries. However, these dyes
are difficult to degrade naturally once they enter the aquatic system.
Their high persistency in natural environment poses a potential health
hazard to all form of life. Hence, there is a need for alternative dye
removal strategy in the environment via bioremediation. In this study,
fungi laccase is investigated via commercial agar dyes plates and
submerged fermentation to explore the application of fungi laccase in
textile dye wastewater treatment. Two locally isolated basidiomycetes
were screened for laccase activity using media added with commercial
dyes such as 2, 2-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid
(ABTS), guaiacol and Remazol Brillant Blue R (RBBR). Isolate TBB3
(1.70±0.06) and EL2 (1.78±0.08) gave the highest results for ABTS
plates with the appearance of greenish halo on around the isolates.
Submerged fermentation performed on Isolate TBB3 with the
productivity 3.9067 U/ml/day, whereas the laccase activity for Isolate
EL2 was much lower (0.2097 U/ml/day). As isolate TBB3 showed
higher laccase production, it was subjected to molecular
characterization by DNA isolation, PCR amplification and sequencing
of ITS region of nuclear ribosomal DNA. After being compared with
other sequences in National Center for Biotechnology Information
(NCBI database), isolate TBB3 is probably from species Trametes
hirsutei. Further research work can be performed on this isolate by
upscale the production of laccase in order to meet the demands of the
requirement for higher enzyme titer for the bioremediation of textile
dyes.
Abstract: Biofuels production has come forth as a future
technology to combat the problem of depleting fossil fuels. Bio-based
ethanol production from enzymatic lignocellulosic biomass
degradation serves an efficient method and catching the eye of
scientific community. High cost of the enzyme is the major obstacle
in preventing the commercialization of this process. Thus main
objective of the present study was to optimize composition of
medium components for enhancing cellulase production by newly
isolated strain of Bacillus tequilensis. Nineteen factors were taken
into account using statistical Plackett-Burman Design. The significant
variables influencing the cellulose production were further employed
in statistical Response Surface Methodology using Central
Composite Design for maximizing cellulase production. The
optimum medium composition for cellulase production was: peptone
(4.94 g/L), ammonium chloride (4.99 g/L), yeast extract (2.00 g/L),
Tween-20 (0.53 g/L), calcium chloride (0.20 g/L) and cobalt chloride
(0.60 g/L) with pH 7, agitation speed 150 rpm and 72 h incubation at
37oC. Analysis of variance (ANOVA) revealed high coefficient of
determination (R2) of 0.99. Maximum cellulase productivity of 11.5
IU/ml was observed against the model predicted value of 13 IU/ml.
This was found to be optimally active at 60oC and pH 5.5.
Abstract: Humic acids (HA) were produced by a Trichoderma
viride strain under submerged fermentation in a medium based on the
oil palm empty fruit bunch (EFB) and the main variables of the
process were optimized by using response surface methodology. A
temperature of 40°C and concentrations of 50g/L EFB, 5.7g/L potato
peptone and 0.11g/L (NH4)2SO4 were the optimum levels of the
variables that maximize the HA production, within the
physicochemical and biological limits of the process. The optimized
conditions led to an experimental HA concentration of 428.4±17.5
mg/L, which validated the prediction from the statistical model of
412.0mg/L. This optimization increased about 7–fold the HA
production previously reported in the literature. Additionally, the
time profiles of HA production and fungal growth confirmed our
previous findings that HA production preferably occurs during fungal
sporulation. The present study demonstrated that T. viride
successfully produced HA via the submerged fermentation of EFB
and the process parameters were successfully optimized using a
statistics-based response surface model. To the best of our
knowledge, the present work is the first report on the optimization of
HA production from EFB by a biotechnological process, whose
feasibility was only pointed out in previous works.
Abstract: Conversion of lignocellulosic biomass is the basis process for production of fuels, chemicals and materials in the sustainable biorefinery industry. Saccharification of lignocellulosic biomass is an essential step which produces sugars for further conversion to target value-added products e.g. bio-ethanol, bio-plastic, g-valerolactone (GVL), 5-hydroxymethylfuroic acid (HMF), levulinic acid, etc. The goal of this work was to develop an efficient enzyme for conversion of biomass to reducing sugar based on crude fungal enzyme from Chaetomium globosum BCC5776 produced by submerged fermentation and evaluate its activity comparing to a commercial Acremonium cellulase. Five local biomasses in Thailand: rice straw, sugarcane bagasse, corncobs, corn stovers, and palm empty fruit bunches were pretreated and hydrolyzed with varying enzyme loadings. Saccharification of the biomass led to different reducing sugar levels from 115 mg/g to 720 mg/g from different types of biomass using cellulase dosage of 9 FPU/g. The reducing sugar will be further employed as sugar feedstock for production of ethanol or commodity chemicals. This work demonstrated the use of promising enzyme candidate for conversion of local lignocellulosic biomass in biorefinery industry.
Abstract: A total of 6 isolates of Bacillus subtilis were isolated from oil mill waste collected in Namakkal district, Tamilnadu, India. The isolated bacteria were screened using lipase screening medium containing Tween 80. BS-3 isolate exhibited a greater clear zone than the others, indicating higher lipase activity. Therefore, this isolate was selected for media optimization studies. Ten process variables were screened using Plackett–Burman design and were further optimized by central composite design of response surface methodology for lipase production in submerged fermentation. Maximum lipase production of 16.627 U/min/ml were predicted in medium containing yeast extract (9.3636g), CaCl2 (0.8986g) and incubation periods (1.813 days). A mean value of 16.98 ± 0.2286 U/min/ml of lipase was acquired from real experiments.
Abstract: Phytases are acid phosphatase enzymes, which
efficiently cleave phosphate moieties from phytic acid, thereby
generating myo-inositol and inorganic phosphate. Thirty four
isolates of endophytic fungi to produce of phytases were isolated
from leaf, stem and root fragments of soybean. Screening of 34
isolates of endophytic fungi identified the phytases produced by
Rhizoctonia sp. and Fusarium verticillioides . The phytase
production were the best induced by phytic acid and rice bran
compared the others inducer in submerged fermentation medium
used. The phytase produced by both Rhizoctonia sp. and F.
verticillioides have pH optimum at 4.0 and 5.0 respectively. The
characterization of phytase from Fusarium verticillioides showed that
temperature optimum was 500C and stability until 600C, the pH
optimum 5.0 and pH stability was 2.5 – 6.0, and substrate specificity
were rice bran>soybean meal>corn> coconut cake, respectively.
Abstract: To investigate the production of cellulases from Aspergillus heteromorphus, submerged fermentation was performed using wheat straw as substrate. Optimization of saccharification conditions like pH, temperature and time were studied. Highest reducing sugar was released on 5th day at 5 pH, 30° C temperature. When A. heteromorphous was grown on wheat straw in submerged fermentation after 5 days incubation at 30 ° C, 3.2 IU/ml and 83 IU/ml, filter paper activity and CMCase activity respectively.
Abstract: Plackett-Burman statistical screening of media
constituents and operational conditions for extracellular lipase
production from isolate Trichoderma viride has been carried out in
submerged fermentation. This statistical design is used in the early
stages of experimentation to screen out unimportant factors from a
large number of possible factors. This design involves screening of
up to 'n-1' variables in just 'n' number of experiments. Regression
coefficients and t-values were calculated by subjecting the
experimental data to statistical analysis using Minitab version 15.
The effects of nine process variables were studied in twelve
experimental trials. Maximum lipase activity of 7.83 μmol /ml /min
was obtained in the 6th trail. Pareto chart illustrates the order of
significance of the variables affecting the lipase production. The
present study concludes that the most significant variables affecting
lipase production were found to be palm oil, yeast extract, K2HPO4,
MgSO4 and CaCl2.