Insect cellulolytic enzymes: Novel sources for degradation of lignocellulosic biomass

Alternative and renewable fuels derived from lignocellulosic biomass offer the potential to reduce our dependence on fossil fuels and mitigate global climate change. Cellulose is one of the major structural components in all lignocellulosic wastes and enzymatic depolymerization of cellulose by cellulases is an essential step in bio-ethanol production. Wood-degrading insects are potential source of biochemical catalysts for converting wood lignocellulose into biofuels. Cellulose digestion has been demonstrated in more than 20 insect families representing ten distinct insect orders. Termite guts been have considered as the “world’s smallest bioreactors” since they digest a significant proportion of cellulose (74-99%) and hemicellulose (65-87%) components of lignocelluloses they ingest. The lower termites harbor protistan symbionts in hindgut whereas higher termites lack these in the hind gut. Studies on cellulose digestion in termites and other insects with reference to ligno-cellulose degrading enzymes have been well focused in this review. The studies on insect cellulolytic systems can lead to the discovery of a variety of novel biocatalysts and genes that encode them, as well as associated unique mechanisms for efficient biomass conversion into biofuels

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

Sequential acid-autoclave and microwave-alkali pretreatment of rice straw for bioethanol production

Two-step acid-autoclave and microwave-alkali pre-treatment process of rice straw have been carried out for bioethanol production. The reaction conditions of both the steps are optimized using Response Surface Methodology. The studies reveal that the optimum conditions for acid-autoclave pretreatment are found to be 1.90 per cent acid concentration, 51.85 min time and 1:17.51 solid:liquid ratio with maximum release of reducing sugars (16.94 g per 100 g) and minimum release of furfurals (0.93 g per 100 g). For second step pretreatment i.e. microwave-alkali, optimized conditions are observed to be 3.75 percent alkali concentration, 9.16 min time and 475W microwave power with minimum lignin content of 2.96 percent in pre-treated straw. Scanning electron micrographs reveal extensive damage of silicified waxy surface and disruption of the cell wall structure of straw after two step pre-treatment process. It has been concluded that sequential pre-treatment of rice straw using acid-autoclave and microwave-alkali process efficiently remove hemicellulose and lignin from straw, thereby increasing accessibility of cellulose to enzymatic hydrolysis for enhanced production of fermentable sugars and bioethanol

H-type tracheo-esophageal fistula in a very low birth weight infant: An unexpected and diagnostic challenge for neonatologist

Tracheo-esophageal fistula (TEF) without associated esophageal atresia or H-type fistula is a rare congenital anomaly. H-type fistula is usually missed in the neonatal period as the presenting symptoms are either of recurrent pneumonia or gastro-esophageal reflux which always lead to delay in diagnosis and infant undergoes unnecessary treatment. We report a case of H-type of TEF, diagnosed within 12 days of birth based upon choking and cyanosis on the first trial of spoon feeds. Diagnosis was confirmed with contrast esophagogram. The infant was operated for it and was successfully discharged

Chitosan-Urea Nanocomposite for Improved Fertilizer Applications: The Effect on the Soil Enzymatic Activities and Microflora Dynamics in N Cycle of Potatoes (Solanum tuberosum L.)

The impact of polymer-based slow-release urea formulations on soil microbial N dynamics in potatoes has been sparingly deciphered. The present study investigated the effect of a biodegradable nano-polymer urea formulation on soil enzymatic activities and microflora involved in the N cycling of potato (Solanum tuberosum L.). The nano-chitosan-urea composite (NCUC) treatment significantly increased the soil dehydrogenase activity, organic carbon content and available potassium compared to the conventional urea (CU) treatment. The soil ammonical nitrogen (NH4+-N) and nitrate nitrogen (NO3−-N) contents and urease activity were significantly decreased in the NCUC-amended soil. The slow urea hydrolysis rate led to low concentrations of NH4+-N and NO3−-N in the tested potato soil. Furthermore, these results corroborate the low count of ammonia oxidizer and nitrate reducer populations. Quantitative PCR (q-PCR) studies revealed that the relative abundance of eubacterial (AOB) and archaeal ammonia-oxidizing (AOA) populations was reduced in the NCUC-treated soil compared to CU. The abundance of AOA was particularly lower than AOB, probably due to the more neutral and alkaline conditions of the tested soil. Our results suggest that the biodegradable polymer urea composite had a significant effect on the microbiota associated with soil N dynamics. Therefore, the developed NCUC could be used as a slow N-release fertilizer for enhanced growth and crop yields of potato

Detection of Leishmania causing visceral Leishmaniasis in the old and new worlds by a polymerase chain reaction assay based on telomeric sequences

We present a new polymerase chain reaction assay based on telomeric sequences of Leishmania donovani. When this assay was used in dilutions of purified L. donovani DNA, a strong amplification signal was observed with 1 fg of DNA. In a specificity test that used purified DNA from Old World and New World Leishmania, the assay recognized all parasites isolated from patients with visceral leishmaniasis, except for 2 isolates of Leishmania colombiensis from Venezuela and 1 isolate from Brazil. All Leishmania major and Leishmania tropica isolates tested were negative, except for one isolate in each species. We also used the assay on fresh and archive bone marrow samples recovered from Giemsa-stained slides and from dried blood stains.573–[email protected]@[email protected]@reacciun.v