The Use of a Fractional Factorial Design to Determine the Factors That Impact 1,3-Propanediol Production from Glycerol by Halanaerobium Hydrogeniformans

In recent years, biodiesel, a substitute for fossil fuels, has led to the excessive production of crude glycerol. The resulting crude glycerol can possess a high concentration of salts and an alkaline pH. Moreover, current crude glycerol purification methods are expensive, rendering this former commodity a waste product. However, Halanaerobium hydrogeniformans, a haloalkaliphilic bacterium, possesses the metabolic capability to convert glycerol into 1,3-propanediol, a valuable commodity compound, without the need for salt dilution or adjusting pH when grown on this waste. Experiments were performed with different combinations of 24 medium components to determine their impact on the production of 1,3-propanediol by using a fractional factorial design. Tested medium components were selected based on data from the organism\u27s genome. Analysis of HPLC data revealed enhanced production of 1,3-propanediol with additional glycerol, pH, vitamin B12, ammonium ions, sodium sulfide, cysteine, iron, and cobalt. However, other selected components; nitrate ions, phosphate ions, sulfate ions, sodium:potassium ratio, chloride, calcium, magnesium, silicon, manganese, zinc, borate, nickel, molybdenum, tungstate, copper and aluminum, did not enhance 1,3-propanediol production. The use of a fractional factorial design enabled the quick and efficient assessment of the impact of 24 different medium components on 1,3-propanediol production from glycerol from a haloalkaliphilic bacterium

Appropriateness of Proton Pump Inhibitor Use in Hospitalized Patients: A Cross Sectional Study in a Tertiary Care Hospital in North India

Background: Proton Pump Inhibitors (PPIs) are often prescribed inappropriately among hospitalized patients and same is often continued even after their discharge from the hospital. The inappropriate use of PPIs leads to an increased risk of adverse effects, drug interaction, and unnecessary hospital expenditure for such patients. Aim of this study was to determine the appropriateness of PPIs use among hospitalized patients. Methods: A cross sectional observational study was conducted on hospitalized patients in a tertiary care hospital in Northern India. The clinical records of adult patients hospitalized during April- May 2022 were assessed for the prescribing pattern and appropriateness of PPI use as per the National Institute of Health and Care Excellence (NICE) guidelines. Results: A total of 192 patient’s records were included in this study with the mean age 57 years and 61% of the study participants were males. Overall, 72% (138) of the study participants were prescribed PPIs by intravenous route and only in 28% (54) cases an oral route was preferred. Pantoprazole was the most commonly prescribed PPI in 112 (58%) patients and it was administered by intravenous route among 87 patients (78%) and by oral route in 25 (22%) patients. PPI use was appropriate in 54% of the cases and they were most commonly prescribed for ulcer prophylaxis. This study identified higher use of PPIs was seen in low risk patients for longer duration than indicated. Conclusion: PPIs are being prescribed inappropriately among hospitalized patient unrelated to their widely accepted clinical indications and are often continued unnecessarily once patient is discharged. These results suggest the need of regular audits on use of PPIs clubbed with educational initiatives to promote rational use of PPIs among hospitalized patients

Media optimization, scale-up and repeated fed-batch operations for the production of 1,3-propanediol from glycerol by halanaerobium hydrogeniformans

The development of renewable energy sources, such as biofuels, is of great interest in today\u27s world due to depletion of fossil fuels and concerns about climate change. The production of the main by-product, crude glycerol, in biodiesel production presents an opportunity for the production of industrially relevant commodities. Crude glycerol in biodiesel waste is highly impure and possesses high salt concentrations and alkalinity, making it infeasible for direct industrial utilization. Moreover, current glycerol purification methods are highly cost-intensive, necessitating a search for cost-effective approaches that are feasible to employ. Genome data analysis of Halanaerobium hydrogeniformans, revealed the metabolic capability of this bacterium to convert glycerol into 1,3-propanediol (PDO), a relevant industrial commodity. To develop an optimum growth medium for this glycerol conversion, assays with different combinations of twenty-four media components were performed. Data analysis using HPLC demonstrated enhanced production of 1,3-propanediol with specific additions of glycerol, pH, vitamin B12, ammonium-ions, sodium sulfide, cysteine, iron and cobalt. Reactor studies were also performed to monitor the production of PDO, as a function of scale up in reactor volume. In addition, the impact of different glycerol concentrations and retained fraction volumes on PDO productivity was determined through repeated fed-batch reactions. Fed-batch operation provided a 39.2 percent increase in PDO concentration and a 61.7 percent increase in the productivity in comparison to the batch operation. Ongoing enzyme kinetics studies are being performed in order to better understand the PDO production pathway. This information will be helpful in modelling the dynamics of culture to maximize the yield and productivity of PDO production --Abstract, page iv

Strategies for Successful Acclimatization and Hardening of In Vitro Regenerated Plants: Challenges and Innovations in Micropropagation Techniques

The micropropagation technique serves as an effective approach for conserving and propagating numerous plant species. Challenges to its success encompass explant selection, media composition, hormone concentration, microbial contamination, incubation conditions, and photoperiod. Beyond these factors, the veracity of tissue culture hinges on successful acclimatization of in vitro regenerated plants to their natural surroundings. Tissue culture-derived plants exhibit characteristic variations like altered nutrition, reduced cuticular wax, non-functional stomata, etc. During transition to natural conditions, a significant portion of micropropagated plants face survival challenges. Studies propose gradual acclimatization processes for smooth adjustment. Ex vitro rooting is advocated for economic, simple, and enhanced survival outcomes. Hydroponics, photoautotrophic acclimatization, and biotization strategies also improve post-transplantation survival. This study evaluates diverse strategies for achieving successful acclimatization of in vitro regenerated plants

Biosorption and Bioleaching of Heavy Metals from Electronic Waste Varied with Microbial Genera

Industrialization and technological advancements have led to the exploitation of natural resources and the production of hazardous wastes, including electronic waste (E-waste). The traditional physical and chemical techniques used to combat E-waste accumulation have inherent drawbacks, such as the production of harmful gases and toxic by-products. These limitations may be prudently addressed by employing green biological methods, such as biosorption and bioleaching. Therefore, this study was aimed at evaluating the biosorption and bioleaching potential of seven microbial cultures using E-waste (printed circuit board (PCB)) as a substrate under submerged culture conditions. The cut pieces of PCB were incubated with seven microbial cultures in liquid broth conditions in three replicates. Atomic absorption spectroscopy (AAS) analysis of the culture biomass and culture filtrates was performed to evaluate and screen the better-performing microbial cultures for biosorption and bioleaching potentials. The best four cultures were further evaluated through SEM, energy-dispersive X-ray spectroscopy (EDX), and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) studies to identify the possible culture that can be utilized for the biological decontamination of E-waste. The study revealed the highest and differential ability of Pleurotus florida and Pseudomonas spp. for biosorption and bioleaching of copper and iron. This can be attributed to bio-catalysis by the laccase enzyme. For both P. florida and Pseudomonas spp. on the 20th day of incubation, laccase exhibited higher specific activity (6.98 U/mg and 5.98 U/mg, respectively) than other microbial cultures. The biomass loaded with Cu2+ and Fe2+ ions after biosorption was used for the desorption process for recovery. The test cultures exhibited variable copper recovery efficiencies varying between 10.5 and 18.0%. Protein characterization through SDS-PAGE of four promising microbial cultures exhibited a higher number of bands in E-waste as compared with microbial cultures without E-waste. The surface topography studies of the E-waste substrate showed etching, as well as deposition of vegetative and spore cells on the surfaces of PCB cards. The EDX studies of the E-waste showed decreases in metal element content (% wt/% atom basis) on microbial treatment from the respective initial concentrations present in non-treated samples, which established the bioleaching phenomenon. Therefore, these microbial cultures can be utilized to develop a biological remediation method to manage E-waste

Biosorption and Bioleaching of Heavy Metals from Electronic Waste Varied with Microbial Genera

Industrialization and technological advancements have led to the exploitation of natural resources and the production of hazardous wastes, including electronic waste (E-waste). The traditional physical and chemical techniques used to combat E-waste accumulation have inherent drawbacks, such as the production of harmful gases and toxic by-products. These limitations may be prudently addressed by employing green biological methods, such as biosorption and bioleaching. Therefore, this study was aimed at evaluating the biosorption and bioleaching potential of seven microbial cultures using E-waste (printed circuit board (PCB)) as a substrate under submerged culture conditions. The cut pieces of PCB were incubated with seven microbial cultures in liquid broth conditions in three replicates. Atomic absorption spectroscopy (AAS) analysis of the culture biomass and culture filtrates was performed to evaluate and screen the better-performing microbial cultures for biosorption and bioleaching potentials. The best four cultures were further evaluated through SEM, energy-dispersive X-ray spectroscopy (EDX), and sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) studies to identify the possible culture that can be utilized for the biological decontamination of E-waste. The study revealed the highest and differential ability of Pleurotus florida and Pseudomonas spp. for biosorption and bioleaching of copper and iron. This can be attributed to bio-catalysis by the laccase enzyme. For both P. florida and Pseudomonas spp. on the 20th day of incubation, laccase exhibited higher specific activity (6.98 U/mg and 5.98 U/mg, respectively) than other microbial cultures. The biomass loaded with Cu2+ and Fe2+ ions after biosorption was used for the desorption process for recovery. The test cultures exhibited variable copper recovery efficiencies varying between 10.5 and 18.0%. Protein characterization through SDS-PAGE of four promising microbial cultures exhibited a higher number of bands in E-waste as compared with microbial cultures without E-waste. The surface topography studies of the E-waste substrate showed etching, as well as deposition of vegetative and spore cells on the surfaces of PCB cards. The EDX studies of the E-waste showed decreases in metal element content (% wt/% atom basis) on microbial treatment from the respective initial concentrations present in non-treated samples, which established the bioleaching phenomenon. Therefore, these microbial cultures can be utilized to develop a biological remediation method to manage E-waste

Red rot resistant transgenic sugarcane developed through expression of β-1,3-glucanase gene.

Sugarcane (Saccharum spp.) is a commercially important crop, vulnerable to fungal disease red rot caused by Colletotrichum falcatum Went. The pathogen attacks sucrose accumulating parenchyma cells of cane stalk leading to severe losses in cane yield and sugar recovery. We report development of red rot resistant transgenic sugarcane through expression of β-1,3-glucanase gene from Trichoderma spp. The transgene integration and its expression were confirmed by quantitative reverse transcription-PCR in first clonal generation raised from T0 plants revealing up to 4.4-fold higher expression, in comparison to non-transgenic sugarcane. Bioassay of transgenic plants with two virulent C. falcatum pathotypes, Cf 08 and Cf 09 causing red rot disease demonstrated that some plants were resistant to Cf 08 and moderately resistant to Cf 09. The electron micrographs of sucrose storing stalk parenchyma cells from these plants displayed characteristic sucrose-filled cells inhibiting Cf 08 hyphae and lysis of Cf 09 hyphae; in contrast, the cells of susceptible plants were sucrose depleted and prone to both the pathotypes. The transgene expression was up-regulated (up to 2.0-fold in leaves and 5.0-fold in roots) after infection, as compared to before infection in resistant plants. The transgene was successfully transmitted to second clonal generation raised from resistant transgenic plants. β-1,3-glucanase protein structural model revealed that active sites Glutamate 628 and Aspartate 569 of the catalytic domain acted as proton donor and nucleophile having role in cleaving β-1,3-glycosidic bonds and pathogen hyphal lysis