Culturable Streptomyces spp. from high-altitude, oligotrophic North Western Himalaya: a comprehensive study on the diversity, bioactivity and insights into the proteome of potential species.

The increasing global concern of antimicrobial resistance and shortage of new antimicrobials necessitates exploring untapped terrestrial environments for new bioactive microbiome diversity. The low-temperature and oligotrophic North Western Himalaya (NWH) region has a vast diversity of Streptomyces with potential antimicrobial properties that remain largely unexplored. This study evaluates the diversity of culturable Streptomyces from high-altitude NWH and their potential as a source of new antimicrobials through genus-specific isolation and identification.

Functional antagonism and insights into the biosynthetic potential of human gut-derived microbes.

The specialised small molecules encoded by commensal microbes mediate distinct functional interactions. However, there is a landscape of antagonistic interactions mediated by specialised strains and their small molecules. Herein, the antagonistic landscape within a collection of 330 human gut-derived commensal microbial strains was elucidated to evaluate antimicrobial interactions as a defensive contributor, and gain new insights into structure-related functions.

Strategizing the human microbiome for small molecules: Approaches and perspectives.

Studies of the human microbiome are providing a deeper understanding of its significance to human health, and increasing evidence links the microbiota with several diseases. Nevertheless, the exact mechanisms involved in human-microbe interactions are mostly undefined. The genomic potential of the human microbiome to biosynthesize distinct molecules outmatches its known chemical space, and small-molecule discovery in this context remains in its infancy.

New approaches for antituberculosis leads from Actinobacteria.

Bioactive metabolites derived from the phylum Actinobacteria represent many of the existing antimicrobial drugs. Compared with other bacterial pathogens, direct preliminary screening by diffusion assays is a limiting factor against Mycobacterium tuberculosis (Mtb) and different methodologies have been used to improve the search for new molecules. However, the concern remains that most of the previously discovered molecules replicate by conventional procedures.

In vitro bactericidal activity of 3-cinnamoyl-4-hydroxy-6-methyl-2-pyrone (CHP) against drug-susceptible, drug-resistant and drug-tolerant isolates of Mycobacterium tuberculosis.

Objectives: Tuberculosis (TB) poses a serious global threat to humans. New bactericidal agents that can shorten treatment duration and target drug resistance still remain a top priority in the discovery of anti-TB drugs. The objective of this study was to investigate the bactericidal potential of 3-cinnamoyl-4-hydroxy-6-methyl-2-pyrone (CHP) against drug-susceptible, drug-resistant clinical isolates and drug-tolerant Mycobacterium tuberculosis.

Identification of dinactin, a macrolide antibiotic, as a natural product-based small molecule targeting Wnt/β-catenin signaling pathway in cancer cells.

Purpose: Despite the fact that hyper-activation of Wnt/β-catenin signaling pathway has been seen in many cancers, including liver, colorectal and lung carcinoma, no small molecule inhibitors are available that specifically target this pathway. In this study, we analyzed the impact of dinactin (DA), an antibiotic ionophore produced by Streptomyces species, as an effective small molecule targeting Wnt/β-catenin signaling pathway in cancer cells.

Methods: We performed MTT assays to investigate cell viability and proliferation after exposure to small molecules.

In vitro evaluation of dinactin, a potent microbial metabolite against Mycobacterium tuberculosis.

Current long duration treatment options and the emergence of drug resistance in tuberculosis (TB) have led to renewed interest in discovery of novel anti-tubercular agents or the scaffolds exhibiting enhanced efficacy with current anti-TB drugs. Herein, dinactin, a potent bioactive macrotetrolide isolated from Streptomyces puniceus AS13, was evaluated against Mycobacterium tuberculosis H37Rv and other susceptible and drug-resistant clinical isolates of M. tuberculosis.

Bovine mastitis: An appraisal of its alternative herbal cure.

Bovine mastitis is globally recognized as the most common and costly disease affecting dairy herds. The disease causes huge financial losses to dairy industries by reduced yield and milk quality, deaths and culling of affected cows and also by associated treatment costs. The disease occurs due to invasion of the mammary glands by pathogenic bacteria followed by their multiplication in the milk producing tissues.

Chemoprofile and functional diversity of fungal and bacterial endophytes and role of ecofactors - A review.

Endophytes represent a hidden world within plants. Almost all plants that are studied harbor one or more endophytes, which help their host to survive against pathogens and changing adverse environmental conditions. Fungal and bacterial endophytes with distinct ecological niches show important biological activities and ecological functions.

Antimicrobial investigation of selected soil actinomycetes isolated from unexplored regions of Kashmir Himalayas, India.

The aim of the present study was to isolate and evaluate the antimicrobial potential of soil actinomycetes of Kashmir Himalayas. The secondary metabolites of actinomycetes are the prominent source of antibiotics. A total of 121 morphologically different actinomycete strains were isolated and screened for antimicrobial activity against various human pathogens.

Novel bioactive molecules from Lentzea violacea strain AS 08 using one strain-many compounds (OSMAC) approach.

A new eudesmane sesquiterpenoid (1), and a new homologue of virginiae butanolide E (2) along with butyl isobutyl phthalate (3) were isolated from, actinomycete-Lentzea violacea strain AS08 isolated from north western Himalayas by stressing on modified one strain-many compounds (OSMAC) method. The structures of the new compounds were elucidated by extensive spectroscopic analyses including 1D, 2D NMR along with HR-ESI-MS and FT-IR data. Herein, a distinctive method was added for inspecting secretory profile of the strain by quantification of extract value of cell free supernatant in different types of culture media fallowed by HPLC profiling of respective extracts, which revealed a highly altered metabolic profile of the strain and formed the base for the selection of media.

Isolation and characterization of alborixin from Streptomyces scabrisporus: A potent cytotoxic agent against human colon (HCT-116) cancer cells.

The ethyl acetate extract from the fermentation broth of an actinomycete strain, identified as Streptomyces scabrisporus isolated from soil of Kashmir Himalayas - India, exhibited significant cytotoxic activity against a panel of human cancer cell lines. The active fraction subjected to column chromatography led to the isolation of pharmacologically potent anticancer compound whose structure was established to be alborixin on the basis of spectral data analysis. The compound exhibited antiproliferative activity against panel of cell lines N2a, MCF-7, MiaPaca-2, PC-3, HCT-116, MDA-MB-231, HL-60 and A-549 cells with IC50 of 9.

Isolation, characterization and HPLC quantification of compounds from Aquilegia fragrans Benth: Their in vitro antibacterial activities against bovine mastitis pathogens.

Ethno-pharmacological Relevance: The underground parts of Aquilegia fragrans are traditionally used for the treatment of wounds and various inflammatory diseases like bovine mastitis. However, there are no reports on the phytochemical characterization and antibacterial studies of A. fragrans.

Inflammation in ischemic stroke: mechanisms, consequences and possible drug targets.

Ischemic stroke is caused when blood flow to the brain is hampered, leading to instant deficiency of nutrients and oxygen required for normal brain functioning. Reperfusion can alleviate damage from stroke if performed immediately after the onset of ischemia however the efficacy of reperfusion is tempered by secondary injury mechanisms. This multifarious sequence of events leads to the commencement of deleterious cycles of inflammation, oxidant stress and apoptosis that finally culminate in delayed death of neuronal cells even when the brain is effectively reperfused.