Nanosynthesis, phycochemical constituents, and pharmacological properties of cyanobacterium Oscillatoria sp.

The Oscillatoria sp., a blue-green alga or cyanobacterium, consists of about 305 species distributed globally. Cyanobacteria are prokaryotes possessing several secondary metabolites that have industrial and biomedical applications. Particularly, the published reviews on Oscillatoria sp. have not recorded any pharmacology, or possible details, while the detailed chemical structures of the alga are reported in the literature. Hence, this study considers pertinent pharmacological activities of the plethora of bioactive components of Oscillatoria sp. Furthermore, the metallic nanoparticles produced with Oscillatoria sp. were documented for plausible antibacterial, antifungal, antioxidant, anticancer, and cytotoxic effects against several cultured human cell lines. The antimicrobial activities of solvent extracts of Oscillatoria sp. and the biotic activities of its derivatives, pyridine, acridine, fatty acids, and triazine were structurally described in detail. To understand the connotations with research gaps and provide some pertinent prospective suggestions for further research on cyanobacteria as potent sources of pharmaceutical utilities, attempts were documented. The compounds of Oscillatoria sp. are a potent source of secondary metabolites that inhibit the cancer cell lines, in vitro. It could be expected that by holistic exploitation, the natural Oscillatoria products, as the source of chemical varieties and comparatively more potent inhibitors, would be explored against pharmacological activities with the integument of SARs.

Prospective Phycocompounds for Developing Therapeutics for Urinary Tract Infection.

Antibiotic resistance of bacteria is causing clinical and public health concerns that are challenging to treat. Infections are becoming more common in the present era, and patients admitted to hospitals often have drug-resistant bacteria that can spread nosocomial infections. Urinary tract infections (UTIs) are among the most common infectious diseases affecting all age groups. There has been an increase in the proportion of bacteria that are resistant to multiple drugs. Herein is a comprehensive update on UTI-associated diseases: cystitis, urethritis, acute urethral syndrome, pyelonephritis, and recurrent UTIs. Further emphasis on the global statistical incidence and recent advancement of the role of natural products in treating notorious infections are described. This updated compendium will inspire the development of novel phycocompounds as the prospective antibacterial candidate.

Recent advancements on antibiotic bioremediation in wastewaters with a focus on algae: an overview.

Antibiotic contamination from hospitals, animal husbandry, and municipal wastewater is graver than imagined, and it possess serious risks to the health of humans and animals, with the emergence of multidrug resistant bacteria; those affect the growth of higher plants too. Conventional wastewater treatment methods adopted today are inadequate for removing antibiotics from wastewater. Intuitively, the remediation process using mixed algae should be effective enough, for which algae-based remediation technologies have emerged as sustainable remedial methods. This review summarized the detection of antibiotics in field water in most countries; a comprehensive overview of algae-based technologies, algal adsorption, accumulation, biodegradation, photodegradation, hydrolysis, and the use of algae-bacteria consortia for the remediation of antibiotics in wastewaters in done. Green algae namely, Chlamydomonas sp., Chlorella sp., C. vulgaris, Spyrogira sp. Scenedesmus quadricauda, S. obliquus, S. dimorphus, Haematoccus pluvialis, and Nannochlopsis sp., had been reporting have 90-100% antibiotic removal efficiency. The integration of bioelectrochemical systems and genetically engineered prokaryotic algal species offer promising avenues for improving antibiotic removal in the future. Overall, this review highlights the need for tenacious research and development of algae-based technologies to reduce antibiotic contamination in aquatic environments, for holistic good.

Investigation of in vitro antimicrobial, antioxidant and antiproliferative activities of Nostoc calcicola biosynthesized gold nanoparticles.

The cyanobacteria are the promising candidate for synthesizing gold nanoparticles (AuNPs), due to their ability to accumulate heavy metals from the cellular environment and additionally contain varied bioactive compounds as reducing and stabilizing agents. This study describes the N2-fixing cyanobacterium Nostoc calcicola-mediated bioreduction of AuNPs and the inherent antimicrobial, antioxidant, and antiproliferative activities in vitro. Biosynthesized Nc-AuNPs were characterized by spectral characterization techniques. The formation of AuNPs was physically confirmed by the colour change from pale green to dark violet. The UV-Vis analysis, further, proved the reduction in Nc-AuNPs with the cyanobacterium and showed a spectral peak at 527 nm. FESEM-EDX images suggested the surface morphology of the NPs as spherical, cuboidal, and size between 20 and 140 nm. The antimicrobial studies of Nc-AuNPs were carried out by agar-well diffusion method and MIC values against five pathogenic bacterial and two fungal strains were noted. The AuNPs exhibited potential antimicrobial activity against h-pathogenic bacteria with inhibitory zones ranging at 11-18 mm; against fungi ranging at 13-17 mm. Significant antioxidant potentialities were explored by a DPPH assay with an IC50 value of 55.97 µg/ mL. Furthermore, in the anticancer efficacy assay, the Nc-AuNPs inhibited cellular proliferation in human breast adenocarcinoma and cervical cancer cell lines at IC50 concentration, 37.3 µg/ml, and 44.5 µg/ml, respectively. Conclusively, N. calcicola would be an excellent source for synthesizing stable colloidal AuNPs that had significant credibility as phycological (algal) nanomedicines as novel prodrugs with multiple bioactivities.

Insight to biotechnological utility of phycochemicals from cyanobacterium Anabaena sp.: An overview.

Cyanobacteria (blue-green algae) are well-known for the ability to excrete extra-cellular products, as a variety of cyanochemicals (phycocompounds) of curio with several extensive therapeutic applications. Among these phycocompound, the cyanotoxins from certain water-bloom forming taxa are toxic to biota, including crocodiles. Failure of current non-renewable source compounds in producing sustainable and non-toxic therapeutics led the urgency of discovering products from natural sources. Particularly, compounds of the filamentous N2-fixing Anabaena sp. have effective antibacterial, antifungal, antioxidant, and anticancer properties. Today, such newer compounds are the potential targets for the possible novel chemical scaffolds, suitable for mainstream-drug development cascades. Bioactive compounds of Anabaena sp. such as, anatoxins, hassallidins and phycobiliproteins have proven their inherent antibacterial, antifungal, and antineoplastic activities, respectively. Herein, the available details of the biomass production and the inherent phyco-constituents namely, alkaloids, lipids, phenols, peptides, proteins, polysaccharides, terpenoids and cyanotoxins are considered, along with geographical distributions and morphological characteristics of the cyanobacterium. The acquisitions of cyanochemicals in recent years have newly addressed several pharmaceutical aliments, and the understanding of the associated molecular interactions of phycochemicals have been considered, for plausible use in drug developments in future.

Recent progression on phytochemicals and pharmacological properties of the filamentous cyanobacterium Lyngbya sp.

The distribution and phytochemistry of the non-nitrogen fixing, filamentous cyanobacterium (blue-green alga) Lyngbya sp., and the inherent antimicrobial and anticancer activities of its phycochemicals as well as of the biosynthesized nanoparticles as their pharmaceutical potencies are considered. Several phycocompounds of curio, apramide, apratoxin, benderamide, cocosamides, deoxymajusculamide, flavonoids, lagunamides, lipids, proteins, amino acids, lyngbyabellin, lyngbyastatin, majusculamide, peptides, etc. were isolated from Lyngbya sp., which had a lot of potential pharmaceutical activities; those compounds had antibacterial, antiviral, antifungal, anticancer, antioxidant, anti-inflammatory, ultraviolet protectant, and other activities. Particularly, several Lyngbya phycocompounds had potent antimicrobial potencies, seen through in vitro controlling of several frequently encountered multidrug-resistant (MDR) clinically belligerent strains of pathogenic bacteria isolated from clinical samples. The aqueous extracts of Lyngbya sp. were used for the synthesis of silver and copper oxide nanoparticles, which were used in pharmacological trials too. The nanoparticles biosynthesized with Lyngbya sp. had several uses such as biofuel, agro-based applications, in cosmetics, and industrial uses as biopolymers, and being potent antimicrobial and anticancer agents and in drug-delivery too, as medical applications. It could be concluded that the Lyngbya phycochemicals and the biosynthesized nanoparticles have future uses as antimicrobial namely as bacterial and fungal and anti-cancer agents, with promising medical and industrial uses.

Biomedical Applications of Biosynthesized Gold Nanoparticles from Cyanobacteria: an Overview.

Recently there had been a great interest in biologically synthesized nanoparticles (NPs) as potential therapeutic agents. The shortcomings of conventional non-biological synthesis methods such as generation of toxic byproducts, energy consumptions, and involved cost have shifted the attention towards green syntheses of NPs. Among noble metal NPs, gold nanoparticles (AuNPs) are the most extensively used ones, owing to the unique physicochemical properties. AuNPs have potential therapeutic applications, as those are synthesized with biomolecules as reducing and stabilizing agent(s). The green method of AuNP synthesis is simple, eco-friendly, non-toxic, and cost-effective with the use of renewable energy sources. Among all taxa, cyanobacteria have attracted considerable attention as nano-biofactories, due to cellular uptake of heavy metals from the environment. The cellular bioactive pigments, enzymes, and polysaccharides acted as reducing and coating agents during the process of biosynthesis. However, cyanobacteria-mediated AuNPs have potential biomedical applications, namely, targeted drug delivery, cancer treatment, gene therapy, antimicrobial agent, biosensors, and imaging.