Bio-composting process development by SSF for utilization agro-industrial wastes

The wastes derived from oil palm industries are generated every year and becoming a great concern, consequently,an urgent development of bio-composting process has been investigated. Bio-composting is an environmental friendly bioconversion process where its products could be utilized as plant growth enhancement. In Malaysia about 50 million tons of Palm Oil Mill Effluents (POME) and about 40 million tones of Oil Palm Biomass (OPB) in forms of empty fruit bunches (EFB), oil palm trunks (OPT), and oil palm fronds (OPF) are generated from palm oil industries every year, the management practice pose significant environmental problems. This study was concerning about simple composting process using selected substrates, POME and EFB plus wheat floor as a cosubstrate.The strains of P. chrysosporium, T. harzianum, A. niger (A 106, S 101), and Penicillium isolated from POME were used for effective bio-composting process. Tray bioreactor was used to evaluate the efficient composting process through solid state bioconversion. The composting time required to complete the process was two months and some parameters were determined to evaluate the compost quality.In the entire process merely, percentage of OM decreased to about 3% while total nitrogen content initially at 0.744 g/g increased to 2.96 g/g. The C/N ratio and GI achieved were 17 and 95 % respectively. The maturity of the compost could be reflected by C/N ratio, pH and GI measurement. The use of POME and EFB as mixed substrates with the induced microorganisms is a new composting trial where it has been expected to receive a good result in order to overcome a conventional composting process

Mobile Banking: The Bangladesh Experience

This study is about the Mobile Banking in Bangladesh. Major objectives of this study are to give an overview about cost, usage and all other benefits of Mobile Banking as well as to produce a scenario of Mobile Banking in Bangladesh. Both the primary and secondary data have been used for the study purpose.  The major findings of this study are 94% respondents think that it saves time than traditional banking, the highest number of respondents use Mobile Banking for ‘Air-time top-up’ service, out of 50 respondents 92% have replied it is less costlier than traditional banking, 100% respondents have agreed that it is speedy, and 100% respondents have opined any type of set can be used for Mobile Banking. Besides, 64% respondents have mentioned that DBBL plays a significant role in mobile baking sector, whereas 28% respondents have agreed that Bkash performs a vital role. Although this concept is new in Bangladesh but its potentiality is high and already it has started to contribute in the economy significantly. From this research, other researchers and policy makers will get an insight about the Mobile Banking in Bangladesh. Keywords:  M- Banking, Bkash, . ICTD, IBMC, SMS, NFC

Ionic liquids as a potential solvent for lipase-catalysed reactions: a review

Ionic liquids (ILs) - as environmentally friendly “green” solvents- have been progressively used in various reactions as reagents, solvents and co-solvents including lipase-catalysed reactions. In fact, lipase-catalysed reactions in ILs are considered as a “green”-reaction and are more advantageous than chemical methods owing to the easy recovery of the product and the mild conditions of the reactions. The use of lipase in ILs provides many technological advantages compared to conventionally used solvents, such as selectivity enhancement, enzyme stability improvement, higher conversion rate, and better recyclability and recovery system. Nevertheless, in some cases, especially in hydrophilic ILs, lipase exhibits activity reduction when compared with organic solvents. Currently, various attempts have been made to enhance the performance of lipases in ILs. The main objective of this review is to demonstrate recent developments in the technology of using ILs as reaction media for lipase. It is expected that this review might be an inspiration in ILs assisted lipase-catalysed reactions to produce value-added materials including biofuels as well as biodiesel

Avirulence gene based RFLP and rep-PCR distinguish the genetic variation of Xanthomonas oryzae pv. oryzae pathotypes in Bangladesh

Bacterial blight (BB) caused by X. oryzae pv. oryzae is one of the devastating diseases of rice mostly in Asia. Genomes of X. oryzae pv. oryzae is highly variable due to rearrangement of the large contents of transposable elements and dynamic changes of X. oryzae pv. oryzae population regulated efficiency of the control measures used for BB management of rice worldwide. In this study, genetic variation of X. oryzae pv. oryzae pathotypes of Bangladesh was studied using aviruelnce gene based RFLP and rep-PCR techniques aimed to formulate pathogen targeted effective control measures against BB of rice. Eight pathotypes of X. oryzae pv. oryzae field isolates were identified based on their reactions against 10 Near Isogenic Lines (NILs). Among eight pathotypes, pathotypes IV and V contained higher number of isolates which were 30.13% and 23.01% respectively while pathotype VIII revealed as minimum containing only 2.51% of total isolates. These eight pathotypes were studied for their genetic variation by RFLP using avrBs3 repeat domain as probe. The results conceded that Bangladeshi X. oryzae pv. oryzae strains seem carrying a minimum of two and maximum of nine avrBs3 family genes homologs. The resistance phenotype on IRBB7 and IRBB10 NILs also indicated presence of two major avrBs3 family genes viz. avrxa7 and avrXa10 in some pathotypes. Relationship of phylogenicity exhibited that X. oryzae pv. oryzae pathotypes assorted into two RFLP haplotypes as well as these haplotypes are largely distributed in Bangladesh. Phylogenetic analyses carried out by (REP, ERIC), rep-PCR and BOX depicted the presence of two main molecular haplotypes of X. oryzae pv. oryzae pathotypes. The relationship between pathotypes and molecular haplotypes of X. oryzae pv. oryzae in Bangladesh indicated that the same lineage possesses different pathotypes and different lineage possesses different pathotypes. The results indicated that eight different pathotypes might have originated from common inherited haplotypes with a wide genetic variation

Optimization of enzymatic pretreatment process for enhanced biogas production from palm oil mill effluent

Anaerobic digestion (AD) of palm oil mill effluent (POME) for biogas production by four step processes such as hydrolysis, acidogenesis, acetogenesis and methanogenesis in which hydrolysis is pondered as a rate limiting step. To achieve high yield of biogas in the AD, enzymatic hydrolysis as the pretreatment method was applied to overcome the current limitation of the existing plants. Therefore, an optimization study was carried out to evaluate AD performance for biogas production. Among the parameters, three factors i.e. cellulase enzyme dose, pH and total suspended solids (TSS) were studied by the face-centered central composite design (FCCCD) under the response surface methodology (RSM) based on lipase pre-treated POME. The results showed that the maximum of 835 ml biogas was obtained with 85% COD removal from 50 ml of POME substrate after 10 days of operation while 290 ml biogas produced from control (without pretreatment). The optimum process conditions were at pH 5 and TSS of 1.5% and enzyme loading 200 CMC/ml. High coefficient of R2 value of 0.994 indicated the satisfactory fit of the model

Ionic liquids as a sustainable platform for Nanocellulose processing from Bioresources: overview and current status

The two-fold threats of the crisis of petrochemical industry-based plastics and serious environmental pollution have triggered the valorization of naturally occurring biopolymers to produce nanocellulose (NC). Nanocellulose has been used extensively in a variety of demanding applications due to its excellent features including biocompatibility, light weight, tunable surface properties, and improved environmental footprint. However, the sustainable production of NC is still confronted with bottlenecks to realize commercial feasibility due to poor solubility and hard processability of biopolymers using conventional hazardous solvents and reagents including concentrated sulfuric acid. The key might rest on the use of ionic liquids (ILs) that have induced a great deal of interest in recent years as powerful “green” solvents for biopolymer processing. ILs can be used as a catalyst and/or reaction medium and/or swelling agent for NC production with an eminent yield of high-quality NC under mild operating conditions coupled with proficient recoverability and recyclability. This review presents the recent technological developments of ILs-assisted proper valorization strategies of numerous bioresources for NC isolation and modification. The impact of IL cation/anion on structural changes of NC is also covered. The major advances in exploring ILs for NC surface modification reactions such as esterification, silylation, and surface plasticization as well as the microscopic insights of NC interaction with ILs are also reviewed. In view of the dominance of green chemistry principles for high purity of the recovered nanocellulose, close R&D endeavors for cheap and biodegradable ILs conjoined with emerging recycling techniques might boost sustainable commercialization

Aflatoxins and Fumonisins Contamination of Maize in Bangladesh: An Emerging Threat for Safe Food and Food Security

Maize (Bhutta) is one of the important growing cereal crops in Bangladesh. Toxigenic fungi such as Aspergillus and Fusarium infect stored maize grains. Enzyme-linked immusorbent assay (ELISA) was used to determine total aflatoxins and fumonisins contamination in stored maize grains collected from 15 Bangladeshi maize-producing areas. The highest total concentration of aflatoxins (103.07 µg/kg) and fumonisin (9.18 mg/kg) was found in Chuadanga and Gaibandha, whereas the lowest was detected for aflatoxins (1.07 µg/kg) and (0.11 mg/kg) in Dinajpur and Cumilla, respectively. The findings clearly demonstrated that aflatoxin concentrations in samples from six regions and fumonisin concentrations in samples from 10 regions were beyond the regulatory limit of aflatoxin (10 ppb) and fumonisin (1 ppm), respectively, as set by European Union (EU). However, a positive correlation between aflatoxins with toxigenic A. flavus, and fumonisins with toxigenic Fusarium spp. was observed. The fungi associated with maize grains were identified by sequencing of ITS regions. Moreover, toxigenic A. flavus was confirmed using primers specific to nor, apa2, omtA and primer FUM1 for F. proliferatum and F. oxysporum. Since the Bangladesh Food Safety Authority has not authorized any precise regulation limits for maize mycotoxin contamination, these results will serve as a benchmark for monitoring mycotoxin contamination in maize and also to develop globally practiced biocontrol approach for producing safe food and feed

Production of cellulase from oil palm biomass as substrate by solid state bioconversion

Solid state bioconversion (SSB) of lignocellulosic material oil palm biomass (OPB) generated from palm oil industries as waste was conducted by evaluating the enzyme production through filamentous fungus in lab-scale experiment. OPB in the form of empty fruit bunches (EFB) was used as the solid substrate and treated with the fungus Trichoderma harzianum to produce cellulase. The results presented in this study revealed that the higher cellulase activity of 0.0413 unit was achieved at the day 3 of fermentation. While the optimum study indicated the enzyme production of 0.0433 unit with moisture content of 50%, 0.0413 unit with 5% v/w of inoculum size and 0.0413 unit with co-substrate concentration of 2% (w/w) at days 9, 9 and 12 of fungal treatment, respectively. The parameters glucosamine and reducing sugar were observed to evaluate the growth and substrate utilization in the experiment