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Abstract: Agricultural residues are produced in large quantities throughout the world. Approximately, 1kg of residue is produced for each kilogram of grains harvested. This ratio of grain/residue translates into an excess of 40 billion ton of crop residue produced each year in the USA. These residues are renewable resources that could be used to produce ethanol and many other value added products. In this study, we demonstrate that the post-harvest sugar cane residue could be used to produce fuel grade ethanol. A chemical pre-treatment process using alkaline peroxide or acid hydrolysis was applied to remove lignin, which acts as physical barrier to cellulolytic enzymes. Yeast Saccharomyces cerevisiae ATCC strain 765 was used in the experiment. The pre-treatment process effectively removed lignin. Ethanol production in the culture sample was monitored using high performance liquid chromatography. The results indicate that ethanol can be made from the sugarcane residue. The fermentation system needs to be optimized further to scale up the process for large-scale production of ethanol from sugar cane residue. [Copyright &y& Elsevier]

Abstract: Two bioremediation methods, namely, soil slurry reactor and land farming technique were evaluated for the treatment of soil contaminated with explosives in Louisiana Army Ammunition Plant, Minden, Louisiana. The soil had a high concentration of 2,4,6-trinitrotoluene (TNT) of 10,000mg/kg of soil and medium level contamination of RDX 1900mg/kg and HMX 900mg/kg of soil. The results indicated that soil slurry reactor under co-metabolic condition with molasses as co-substrate removed TNT more efficiently than land farming method. TNT removal efficiency was 99% in soil slurry reactor compared to 82% in land farming after 182 days. HMX and RDX were also removed from the soil in both methods, but the removal efficiency was low. The radiolabeled study showed that soil microbes mineralize TNT. The mass-balance of TNT indicated 23.5% of TNT was mineralized to CO2, 22.6% was converted to biomass, and 52.3% was converted to various TNT intermediates in the soil slurry reactor. Both methods maintained high bacterial population fairly well. The results of this bench-scale study are promising with regard to transferring the technology to full-scale application at this site. [Copyright &y& Elsevier]

Abstract: The Formosan subterranean termite, Coptotermes formosanus Shiraki, is an aggressive, invasive termite species that has caused billions of dollars of damage across the United States for the past 50 years. Termites depend on intestinal microorganisms for cellulose digestion. Symbiotic microorganisms in the termite gut play key physiological functions such as cellulose and hemicellulose digestion, acetogenesis, hydrogenesis, methanogenesis, sulfate reduction, and nitrogen fixation. Additionally, intestinal microbes create suitable conditions for symbiotic protozoans through the production of nutrients and the maintenance of the pH and the anaerobic conditions in the gut. Although extensive research has been done on the symbiotic relationship of these termites and the microbes found in its gut, there is little information available on the role of facultative anaerobes in the gut. We isolated four enteric bacteria from the hindgut of Formosan subterranean termite, C. formosanus. All isolates were facultative anaerobes and G−. The isolates were identified as Serratia marcescens, Enterobacter aerogens, Enterobacter cloacae, and Citrobacter farmeri by using BIOLOG assay and fatty acid methyl ester analysis (FAME). Each isolate was characterized using sodium dodecyl sulfate (SDS) polyacrylamide gel electrophoresis and biochemical study. This is the first report on the presence of facultative microbes in termite gut. Results of this first study on facultative microbes in the termite gut indicate that the role of facultative organisms in the Formosan termite gut may be to scavenge oxygen and create anaerobic conditions for the anaerobic microorganisms, which are essential for digestion of cellulose consumed by the termite. [Copyright &y& Elsevier]

The overuse and improper disposal of antibiotics results in antibiotic resistance. This raises concern over the presence of antibiotic resistant bacteria (ARB) in waterways and pose health risks of antibiotic resistant infections to water recreationists. The purpose of this study was to monitor water quality, microbial ecology, and antibiotic resistance in water and biofilm on submerged plastics at two public boat launches in southeastern Louisiana. Water and biofilm samples were collected once a month, in triplicate, from two public boat launches in Louisiana, USA for a year. Water quality metrics included nitrate, ammonia, sulfate, phosphate, and organic carbon. Water samples were tested for total and fecal coliform abundance and the presence of ARB. Out of 131 bacterial isolates studied from these two sites, 86% of them tested positive for antibiotic resistance with multi-drug resistance. Antibiotic resistance genes (ARGs) for sulfonamide (sul2), bacitracin (bacA) and ampicillin (ampA) were identified in bacterial isolates from water and biofilm samples at both sites. Molecular genetic diversity analysis identified distinct taxonomic diversity differences in biofilm bacteria compared to the planktonic bacteria in the surrounding water. Biofilm samples showed increased diversity at the phylum, genus, and species levels., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier Ltd. All rights reserved.)