Publications by authors named "Janak R Khatiwada"

Animal translocations provide striking examples of the human footprint on biodiversity. Combining continental-wide genomic and DNA-barcoding analyses, we reconstructed the historical biogeography of the Asian black-spined toad (Duttaphrynus melanostictus), a toxic commensal amphibian that currently threatens two biodiversity hotspots through biological invasions (Wallacea and Madagascar). The results emphasize a complex diversification shaped by speciation and mitochondrial introgression that comprises two distinct species.

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  • Most marine microalgae are usually grown in coastal areas, but this 185-day study successfully cultivated Nannochloropsis oceanica inland using new photobioreactors (PBRs) of varying sizes.
  • A 700-liter PBR showed better adaptability to seasonal changes and produced nearly equal lipid content compared to smaller 150-liter PBRs, suggesting good performance in colder temperatures.
  • The study found that the average production cost of N. oceanica was about $11.89 per kg, which is significantly lower than the market price of $20.19 per kg; smaller PBRs were noted to be more cost-effective for energy prices.
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Bioproduction is considered a promising alternative way of obtaining useful and green chemicals. However, the downstream process of biomolecules has been one of the major difficulties in upscaling the application of bioproducts due to the high purification cost. Acid precipitation is the most common method for purifying biosurfactants from the fermentation broth with high purity.

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  • * Optimal conditions for enzyme production differ between the two bacteria; Cellulomonas sp. works best at room temperature (25-26℃) and pH 7 while Bacillus sp. prefers room temperature and a higher pH of 10, yielding distinct pectinase activities.
  • * Agro-waste substrates like orange peel and barley straw are effective for enzyme production, with orange peel being ideal for pectinase and cellulase, whereas barley
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  • - Soil bacteria can survive harsh conditions and produce harmful factors through processes like autoaggregation, biofilm formation, and resistance to antibiotics and heavy metals.
  • - This study examined six cellulolytic bacteria from soil for their virulence traits, resistance to antibiotics/heavy metals, and ability to form biofilms, revealing that some strains showed significant protective abilities.
  • - Although certain strains demonstrated virulence characteristics, further genetic research is needed to fully understand the mechanisms behind their resistance and pathogenic potential.
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Modern society has a great challenge to decrease waste and minimize the adverse effects of wastes on the economy, environment, and individual health. Thus, this study focuses on the use of eight agro-wastes (banana peel, barley straw, canola straw, pomegranate peel, orange peel, pumpkin pulp+seeds, maple leaf, and brewer's spent grains) by a novel bacterium (Streptomyces thermocarboxydus) for enzymes production. Further, the study explored the subsequent degradation of those wastes by the bacterium.

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The cultural parameters of Streptomyces sp. for pectinase production were optimized using the Box-Behnken design. The maximum pectinase production was obtained after 58 h at 35°C and pH 7 upon submerged fermentation in yeast extract-containing media.

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  • The study identified a bacterium capable of producing multiple enzymes, including pectinase, that was isolated from a contaminated broth through 16S rDNA sequence analysis.
  • The bacterium showed the best enzyme production using orange peel as a substrate, achieving maximum activity levels under specific optimal conditions (40°C, 24-hour incubation, and certain concentrations).
  • Additionally, the bacterium demonstrated potential for producing bacterial lipids, making it a promising candidate for environmental waste management and biofuel production.
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  • Researchers isolated six cellulose-degrading bacteria from soil samples at Kingfisher Lake and the University of Manitoba, identified as different species including Paenarthrobacter sp. and Bacillus sp.
  • The cellulase production of these bacteria was optimized by adjusting environmental conditions like pH, temperature, and substrate concentration, resulting in significant enzyme activity.
  • Sucrose was found to greatly enhance cellulase activity, supporting the potential use of these bacteria as biocatalysts for converting cellulose into glucose in industrial applications.
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Chrysotila dentata is an ecologically important marine alga contributing to the coccolith formation. In this study, a complete chloroplast (cp DNA) genome of Chrysotila dentata was sequenced by using Illumina Hiseq and was analyzed with the help of a bioinformatics tool CPGAVAS2. The circular chloroplast genome of Chrysotila dentata has a size of 109,017 bp with two inverted repeats (IRs) regions (4513 bp each) which is a common feature in most land plants and algal species.

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Studying the pattern of species richness is crucial in understanding the diversity and distribution of organisms in the earth. Climate and human influences are the major driving factors that directly influence the large-scale distributions of plant species, including gymnosperms. Understanding how gymnosperms respond to climate, topography, and human-induced changes is useful in predicting the impacts of global change.

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Understanding the thermal ecology of active amphibians, as well as its relationship with habitat and environmental features, is a central theme in ecology. However, this topic has been poorly studied in eastern Himalaya, which is a global biodiversity hotspot. To bridge this gap, we investigated how the body temperatures of active amphibians varied along an elevation gradient in the Arun and Tamor River catchments in eastern Nepal Himalaya in the present study.

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Exposure to hog barn organic dust contributes to occupational lung diseases, which are mediated by inflammatory and oxidative stress pathways. Isoprostanes-a family of eicosanoids produced by oxidation of phospholipids by oxygen radicals-are biomarkers of pulmonary oxidative stress. Importantly, 8-isoprostane has been implicated as a key biomarker and mediator of oxidative stress because it is a potent pulmonary vasoconstrictor.

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Background: Species richness and composition pattern of amphibians along elevation gradients in eastern Nepal Himalaya are rarely investigated. This is a first ever study in the Himalayan elevation gradient, the world's highest mountain range and are highly sensitive to the effects of recent global changes. The aim of the present study was to assess amphibian community structure along elevation gradients and identify the potential drivers that regulate community structures.

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Musk deer Moschus spp. are endemic to the high mountain forests of central Asia. The taxonomic status of musk deer in the central and western Himalayas is poorly understood.

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An upsurge in anthropogenic impacts has hastened the decline of the red panda (). The red panda is a global conservation icon, but holistic conservation management has been hampered by research being restricted to certain locations and population clusters. Building a comprehensive potential habitat map for the red panda is imperative to advance the conservation effort and ensure coordinated management across international boundaries.

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Global climatic transitions and Tibetan Plateau uplifts are hypothesized to have profoundly impacted biodiversity in southeastern Asia. To further test the hypotheses related to the impacts of these incidents, we investigated the diversification patterns of the newt genus , distributed across the mountain ranges of southeastern Asia. Gene-tree and species-tree analyses of two mitochondrial genes and two nuclear genes revealed five major clades in the genus, and suggested several cryptic species.

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Human norovirus (NoV) is the leading cause of foodborne illnesses in the United States. Norovirus is shed in high numbers in the feces and vomitous of infected individuals. Contact surfaces contaminated with bodily fluids harboring infectious virus particles serve as vehicles for pathogen transmission.

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A new species of the genus Microhyla is described from Jamun Khadi, Jhapa district of eastern Nepal, based on molecular and morphological comparisons. This species is the sister taxon of Microhyla ornata and can be distinguished by a unique vocalization, morphology and molecular phylogeny. The uncorrected genetic divergences based on rRNA gene between the new species and its closest congeners, M.

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Proanthocyanidins are oligomeric flavonoids found in plant sources, most notably in apples, cinnamon, grape skin and cocoa beans. They have been also found in substantial amounts in cranberry, black currant, green tea, black tea and peanut skins. These compounds have been recently investigated for their health benefits.

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