Screening and characterization of extracellular cellulase enzyme produced by wild edible mushroom Pleurotus giganteus

195-199Cellulase is a class of enzyme that has great industrial importance. Cellulase catalyzes the hydrolysis of 1, 4 β-D glycosidic linkages in cellulose are mainly produced from a wide variety of microorganisms like fungi, bacteria and protozoan. The present study aimed at the screening and production of extracellular cellulase enzyme produced by a wild edible mushroom Pleurotus giganteus. Different physical and chemical parameters such as temperature, pH, substrate concentration and reaction time on cellulase activity were also studied. The clear yellowish zone around mycelial plug revealed that screening of extracellular cellulase activity of P. giganteus was positive. Cellulase production by using the mushroom was highest after 6 days of the incubation period. Extracellular cellulase activity was maximum at 50 oC temperature, pH 5, 1.4% of substrate concentration (Carboxy-methylcellulose) and 30 minutes of reaction time. The present investigation revealed that wild edible mushroom P. giganteus may be utilized as a source for the production of industrial cellulase

Screening and characterization of extracellular cellulase enzyme produced by wild edible mushroom Pleurotus giganteus

Cellulase is a class of enzyme that has great industrial importance. Cellulase catalyzes the hydrolysis of 1, 4 β-D glycosidic linkages in cellulose are mainly produced from a wide variety of microorganisms like fungi, bacteria and protozoan. The present study aimed at the screening and production of extracellular cellulase enzyme produced by a wild edible mushroom Pleurotus giganteus. Different physical and chemical parameters such as temperature, pH, substrate concentration and reaction time on cellulase activity were also studied. The clear yellowish zone around mycelial plug revealed that screening of extracellular cellulase activity of P. giganteus was positive. Cellulase production by using the mushroom was highest after 6 days of the incubation period. Extracellular cellulase activity was maximum at 50 oC temperature, pH 5, 1.4% of substrate concentration (Carboxy-methylcellulose) and 30 minutes of reaction time. The present investigation revealed that wild edible mushroom P. giganteus may be utilized as a source for the production of industrial cellulase

Heat Killed Attenuated Leishmania Induces Apoptosis of HepG2 Cells Through ROS Mediated p53 Dependent Mitochondrial Pathway

Cytotoxic effect of attenuated Leishmania on liver cancer cells by inducing ROS generation. Methods: Spectrophotometric study to analyze cell death and levels of different active caspases. Flow cytometric study was done to analyze apoptosis induction and ROS generation and levels of different protein. Western blot analysis was performed to study the levels of protein. Confocal microscopy was done to ascertain the expression of different apoptotic markers. Results: We have now observed that attenuated Leishmania donovani UR6 also has potentiality towards growth inhibition of HepG2 cells and investigated the mechanism of action. The effect is associated with increased DNA fragmentation, rise in number of annexinV positive cells, and cell cycle arrest at G1 phase. The detection of unregulated levels of active PARP, cleaved caspases 3 and 9, cytosolic cytochrome C, Bax, and Bad, along with the observed downregulation of Bcl-2 and loss of mitochondrial membrane potential suggested the involvement of mitochondrial pathway. Enhanced ROS and p53 levels regulate the apoptosis of HepG2 cells. NAC was found to inhibit p53 production but PFT-α has no effect on ROS generation. In conclusion, Leishmania donovani UR6 efficiently induces apoptosis in HepG2 cells through ROS mediated p53 dependent mitochondrial pathway. Conclusion: It has been reported earlier that some parasites show prominent cytotoxic effect and prevent tumor growth. From our study we found that Leishmania donovani UR6 efficiently induced apoptosis in HepG2 cells through ROS mediated p53 dependent mitochondrial pathway. This study has rejuvenated the age old idea of bio-therap

Bio-Monitoring of airborne fungi and antifungal activity of Clerodendrum infortanum L. against dominant fungi

The present study provides baseline information on the quantitative and qualitative estimation of aeromycoflora. Burkard personal airsampler and Anderson two stage airsampler were used to detect the quantitative and qualitative estimation of aeromycoflora. 17 non-viable fungal spores were recorded with the aid of Burkard personal airsampler and 12 viable fungal genera were detected using Anderson two stage airsampler. Higher concentration airborne fungi observed in the month of March. Aspergillus sp, Ascospore, Basidiospore, Curvularia sp, Alternaria sp were found to be Nigrospora sp most predominant nonviable fungal genera whereas dominant viable genera were Aspergillus sp, Penicillium sp, Cladosporium sp, Curvularia sp, Trichoderma sp and  Fusarium sp in both the environments. The result of antifungal potential of Clerodendrum infortunatum showed highest efficacy against Aspergillus sp followed by Penicillium sp and Fusarium sp. This present study provided the baseline information about the viable and non-viable concentration in the study sites. Besides the outcomes of this study along with the insightful explanation could aptly provide basis for strategizing effective preventive measures against airborne-fungi. Those are responsible for causing different agricultural crops diseases and human respiratory ailments

Pro-Oxidant Therapeutic Activities of Cerium Oxide Nanoparticles in Colorectal Carcinoma Cells

Given that basal levels of reactive oxygen species (ROS) are higher in cancer cells, there is a growing school of thought that endorses pro-oxidants as potential chemotherapeutic agents. Intriguingly, cerium oxide (CeO2) nanoparticles can manifest either anti- or pro-oxidant activity as a function of differential pH of various subcellular localizations. In an acidic pH environment, for example, in extracellular milieu of cancer cells, CeO2 would function as a pro-oxidant. Based on this concept, the present study is designed to investigate the pro-oxidant activities of CeO2 in human colorectal carcinoma cell line (HCT 116). For comparison, we have also studied the effect of ceria nanoparticles on human embryonic kidney (HEK 293) cells. Dose-dependent viability of cancerous as well as normal cells has been assessed by treating them independently with CeO2 nanoparticles of different concentrations (5-100 mu g/mL) in the culture media. The half maximal inhibitory concentration (IC50) of nanoceria for HCT 116 is found to be 50.48 mu g/mL while that for the HEK 293 cell line is 92.03 mu g/mL. To understand the intricate molecular mechanisms of CeO2-induced cellular apoptosis, a series of experiments have been conducted. The apoptosis-inducing ability of nanoceria has been investigated by Annexin V-FITC staining, caspase 3/9 analysis, cytochrome c release, intracellular ROS analysis, and mitochondrial membrane potential analysis using flow cytometry. Experimental data suggest that CeO2 treatment causes DNA fragmentation through enhanced generation of ROS, which ultimately leads to cellular apoptosis through the p53-dependent mitochondrial signaling pathway

The cost-benefit analysis and constraints of pineapple production in Bangladesh

The main purpose of the study was to estimate the profitability of pineapple production in Sreemangal, Moulvibazar District. Structured questionnaires and face to face interviews were done to collect raw data from 100 pineapple farmers during harvesting season. These farmers were chosen using a multi-stage sampling approach. Net return analysis, Benefit-Cost Ratio, and Kruskal-Wallis One Way Analysis of Variance (ANOVA) were used to analyze the prepared data. Findings from net return analysis showed that pineapple production was a profitable activity in the study area. The total cost of production was Tk. 740,767 and the total return was also substantial, resulting in a net return of Tk. 501,445 for pineapple production. The Benefit-Cost Ratio (BCR) was 1.48, indicating that pineapple farming was profitable for the farmers. However, the study also discovered several constraints perceived by the farmers that hindered pineapple production. These constraints included issues like animal damage, lack of credit availability, natural calamities, labor supply shortages, expensive fertilizer, inadequate storage facilities, and poor seed quality. By mitigating these constraints, pineapple productivity may rise not just in the study area but also in other regions of Bangladesh where the fruit is grown intensively. Thus, this improvement could significantly contribute to the well-being of farmers and enhance their disposable income

Arbuscular mycorrhiza and dark septate endophyte fungal associations of Oryza sativa L. under field condition: colonization features and their occurrence

The present study was aimed to study monthly colonization of arbuscular mycorrhizal (AM) and dark septate endophyte (DSE) fungal associations in rice. The presence of mycorrhizal structures in the roots confirms the colonization by AM fungi. The pattern of hyphae and arbuscules denotes Arum type of AM fungal morphology. The presence of dark coloured septate hyphae running frequently on the epidermal layer and in root cortex and the occurrence of microsclerotia marks the colonization by DSE fungi. The co-occurrence of both AM and DSE fungi ensure dual colonization by two distinct fungal groups. There was significant increase in arbuscules, vesicles and hyphal percentages from first to third month in both the samples collected from two sites. In the third month, AM colonization significantly higher in both the sites. DSE colonization percentages do not differ significantly in first to third month. A total of nine AM fungal species were recovered from two sites. This study is an effort to make aware the local farmers about the usefulness of these native AM mycobiota which can be a preferable choice over chemical fertilizers leading to ecofriendly organic farming

A Novel Fractional Order Fuzzy PID Controller and Its Optimal Time Domain Tuning Based on Integral Performance Indices

A novel fractional order (FO) fuzzy Proportional-Integral-Derivative (PID) controller has been proposed in this paper which works on the closed loop error and its fractional derivative as the input and has a fractional integrator in its output. The fractional order differ-integrations in the proposed fuzzy logic controller (FLC) are kept as design variables along with the input-output scaling factors (SF) and are optimized with Genetic Algorithm (GA) while minimizing several integral error indices along with the control signal as the objective function. Simulations studies are carried out to control a delayed nonlinear process and an open loop unstable process with time delay. The closed loop performances and controller efforts in each case are compared with conventional PID, fuzzy PID and PI{\lambda}D{\mu} controller subjected to different integral performance indices. Simulation results show that the proposed fractional order fuzzy PID controller outperforms the others in most cases.Comment: 30 pages, 20 figure