Pharmaceutically active secondary metabolites of microorganisms (original) (raw)

Antibiotics as microbial secondary metabolites: Production and application

2012

Of all the microbial products manufactured commercially, antibiotics are the most important.Hundreds of antibiotics, a fraction of about 7000 antibiotics known so far, are commercially manufactured using microbial fermentation.In history, the first antibiotic discovered was used for controlling infections, but today more antibiotics are being used for other therapeutic applications. Being the most studied secondary metabolites through the history, antibiotics possess other pharmacological characteristics useful in the medical field. Therefore, the aim of this study is to present a review on antibiotics that include antibiotics definition, classification, mode of actions, uses, antibiotic resistance, side effects, type of antibiotics, metabolisms and determination methods of antibiotics.

Therapeutic Spectrum of Bacterial Metabolites

Indo Global Journal of Pharmaceutical Sciences

Bacterial metabolites have been immensely useful as antibiotics, hence most of the work on the subject revolved around understanding their antibiotic properties. However, it emerged from current literature that they are pleotropic in nature as they express a broad array of activities with potential therapeutic significance. These characteristics include, but are not limited to anticancer, antiviral, antitrypanosomal, antidiabetic adjuvants, anti-inflammatory, hepatoprotective etc. A structural classification of the bacterial metabolites has been given based on the structures re-drawn from the published data. Role of the structural motifs, thought to be primarily present in fungal and plant (eukaryotic) metabolites but now reported in bacterial metabolites as well, have been discussed in light of their multifaceted activities. An analysis of the current literature pertaining to diverse therapeutic properties of the bacterial metabolites is presented.

Antimicrobial Activity of Secondary Metabolites in Medicinal Plants: An Update

2023

Plants have filled in as a significant wellspring of elements for conventional drugs for centuries. Verifiable records and present day ethno botanical field examines feature their significance in the conventional treatment of irresistible malady. Be that as it may, plants form just a minor level of present collection of FDA-endorsed antimicrobial medications. The present article gives an outline of active components of plants as hint for other wellspring of antimicrobial agents to be used in the battle against microscopic organisms. It additionally surveys the ethno botanical way to deal with sedate disclosure and talks about various inventive focuses for future medication revelation endeavours in this field. Without an uncertainty, antimicrobials are miracle tranquilizers. They have represented a very long time against different irresistible infections and spared a huge number of lives. The ongoing disappointment of antimicrobials because of the sensational rise of multidrug-safe microbes and fast spread of new diseases, be that as it may, prompts wellbeing associations and the pharmaceutical business worldwide to change their methodology and to expand improvement of antimicrobials against quickly rising anti-infection safe microorganisms. In spite of the fact that there is thinking about elective wellsprings of characteristic antimicrobial molecules from plants having different methods of activity, some of which have been utilized in regular medication for a considerable length of time and have appeared to have serious impacts contrasted with other antimicrobials. This examination portrays plant intensity as an elective hotspot for antimicrobial agents.

Evaluation of the antimicrobial activity of some fungal secondary metabolite

EurAsian Journal of BioSciences, 2020

The inhibitory effect of the prepared secondary metabolite against pathogenic bacteria subjected during the present study compared with antimicrobial standard agent Chloramphenicol on bacterial growth was studied using Agar well diffusion method. The results show inhibitory activity against subjected bacterial isolates when compared with Chloramphenicol. The results of statistical analysis revealed significant differences between concentrations against bacterial isolates. Staphylococcus aureus was the most sensitive to the secondary metabolite in the study while the three subjected bacteria show a different mode of inhibition related to the high activity of the applied, compound also the results show that the secondary metabolite show high inhibitory effects especially in the 150mg/ml concentrations, the inhibitory activity increase with the increase of secondary metabolite concentration. The statistical analysis of the results showed of the inhibitory effect of Trichoderm koningii secondary metabolite on the growth of Trichophyton mentagrophytes , Microsporum canis, and T. verrucosum, there are significant differences below the level of probability (P<0.05) between the inhibitory effects of Trichoderm koningii secondary metabolite studied different concentrations, compared with the standard antifungal fluconazole. The secondary metabolite of the Trichoderm koningii gave higher inhibition impact compared with the inhibitory effect of antifungal fluconazole at the concentration 100%, The statistical analysis of the results showed the inhibitory effect of Trichoderm viride secondary metabolite on the growth of Trichophyton mentagrophytes , Microsporum canis, and T. verrucosum, Diameter average of inhibition at concentrations of 75% was (30, 27, 29)mm, respectively, and diameter average of inhibition at the concentrations of 50% (24, 22, 26) mm, respectively, whereas diameter average of inhibition at the concentrations 25% (22, 20, 23) mm of fungal genera respectively.

Antifungal activity of microbial secondary metabolites

2011

Secondary metabolites are well known for their ability to impede other microorganisms. Reanalysis of a screen of natural products using the Caenorhabditis elegans-Candida albicans infection model identified twelve microbial secondary metabolites capable of conferring an increase in survival to infected nematodes. In this screen, the two compound treatments conferring the highest survival rates were members of the epipolythiodioxopiperazine (ETP) family of fungal secondary metabolites, acetylgliotoxin and a derivative of hyalodendrin. The abundance of fungal secondary metabolites indentified in this screen prompted further studies investigating the interaction between opportunistic pathogenic fungi and Aspergillus fumigatus, because of the ability of the fungus to produce a plethora of secondary metabolites, including the well studied ETP gliotoxin. We found that cell-free supernatant of A. fumigatus was able to inhibit the growth of Candida albicans through the production of a secreted product. Comparative studies between a wild-type and an A. fumigatus ΔgliP strain unable to synthesize gliotoxin demonstrate that this secondary metabolite is the major factor responsible for the inhibition. Although toxic to organisms, gliotoxin conferred an increase in survival to C. albicans-infected C. elegans in a dose dependent manner. As A. fumigatus produces gliotoxin in vivo, we propose that in addition to being a virulence factor, gliotoxin may also provide an advantage to A. fumigatus when infecting a host that harbors other opportunistic fungi.

Impact of novel microbial secondary metabolites on the pharma industry

Applied Microbiology and Biotechnology, 2022

Microorganisms are remarkable producers of a wide diversity of natural products that significantly improve human health and well-being. Currently, these natural products comprise half of all the pharmaceuticals on the market. After the discovery of penicillin by Alexander Fleming 85 years ago, the search for and study of antibiotics began to gain relevance as drugs. Since then, antibiotics have played a valuable role in treating infectious diseases and have saved many human lives. New molecules with anticancer, hypocholesterolemic, and immunosuppressive activity have now been introduced to treat other relevant diseases. Smaller biotechnology companies and academic laboratories generate novel antibiotics and other secondary metabolites that big pharmaceutical companies no longer develop. The purpose of this review is to illustrate some of the recent developments and to show the potential that some modern technologies like metagenomics and genome mining offer for the discovery and development of new molecules, with different functions like therapeutic alternatives needed to overcome current severe problems, such as the SARS-CoV-2 pandemic, antibiotic resistance, and other emerging diseases. Key points • Novel alternatives for the treatment of infections caused by bacteria, fungi, and viruses. • Second wave of efforts of microbial origin against SARS-CoV-2 and related variants. • Microbial drugs used in clinical practice as hypocholesterolemic agents, immunosuppressants, and anticancer therapy. Keywords Microbial natural products • Antibiotics • Hypocholesterolemics • Anticancer drugs • Immunosuppressants • Antibiotic resistance Abbreviations FDA Food and Drug Administration NA Not applicable cSSSI Complicated skin, and skin structure infections ABSSSIs Acute bacterial skin, and skin structure infections cUTI Complicated urinary tract infections cIAI Complicated intra-abdominal infections HABP/VABP Hospital-acquired bacterial pneumonia, and ventilator-associated bacterial pneumonia CABP Community-acquired bacterial pneumonia. Estimate of U.S. Sales for 2018 was based on data previously reported Carr and Stringer 2019 This review isdedicated to the memory of Prof. Arnold L. Demain, who passed away while thispaper was being written.

Sources of novel antibiotics—aside the common roads

Applied Microbiology and Biotechnology, 2010

Microbial pathogens are becoming increasingly resistant to available treatments, and new antibiotics are badly needed, but the pipeline of compounds under development is scarce. Furthermore, the majority of antibiotics under development are improved derivatives of marketed compounds, which are at best only partially effective against prevailing resistance mechanisms. In contrast, antibiotics endowed with new mechanisms of action are expected to be highly effective against multi-drug resistant pathogens. In this review, examples are provided of new antibiotics classes in late discovery or clinical development, arising from three different avenues: (1) compounds discovered and never brought to market by large pharmaceutical companies; (2) old compounds reanalyzed and rejuvinated with today's tools; and (3) newly discovered molecules. For each compound, we will briefly describe original discovery, mechanism of action, any known resistance, antimicrobial profile, and current status of development. Keywords Antibiotics. Natural products. Drug resistance Searching on big pharma's dusty shelves During the golden era of antibiotic discovery, thousands of antibiotics were discovered, mostly from microbial sources. At a time of plenty, only few made it to the market, leaving S

Antifungal metabolites, their novel sources, and targets to combat drug resistance

Frontiers in Microbiology

Excessive antibiotic prescriptions as well as their misuse in agriculture are the main causes of antimicrobial resistance which poses a growing threat to public health. It necessitates the search for novel chemicals to combat drug resistance. Since ancient times, naturally occurring medicines have been employed and the enormous variety of bioactive chemicals found in nature has long served as an inspiration for researchers looking for possible therapeutics. Secondary metabolites from microorganisms, particularly those from actinomycetes, have made it incredibly easy to find new molecules. Different actinomycetes species account for more than 70% of naturally generated antibiotics currently used in medicine, and they also produce a variety of secondary metabolites, including pigments, enzymes, and anti-inflammatory compounds. They continue to be a crucial source of fresh chemical diversity and a crucial component of drug discovery. This review summarizes some uncommon sources of anti...

ANTIFUNGAL POTENTIAL OF BACTERIAL METABOLITES: ISOLATION, SCREENING AND CHARACTERIZATION

The increased use of antimicrobial agents resulted in the development of resistance against most of the commonly used antimicrobial drugs. Therefore the need for safe and effective antimicrobial agent have increased with time. This study was designed in an attempt to search for such natural antimicrobial agents against fungi. A total of fifty five indigenous bacterial strains were collected from different clinical specimens. These strains were identified by conventional methods as Staphylococcus aureus, S. epidermidis, Bacillus subtilis, Pseudomonas aeruginosa, Proteus mirabilis and P. vulgaris. The cell free culture supernatant (CFS) of these strains were used in antifungal screening by using agar well diffusion assay against different fungal strains. Of all the bacterial strains screened, 36.4% (20/55) showed antifungal potential. However, S. aureus, B. subtilis and P. mirabilis demonstrated bioactivity against some fungal strains but 71.4% (15/21) strains of P.aeruginosa demonstrated significant antifungal activity. The most potent antifungal strains P. aeruginosa strains MS 9 and MS 10 exhibited antifungal activity against Rhizopus sp., Aspergillus spp., Penicillium sp., Microsporum sp., Trichophyton spp. and Saccharomyces species. However, no activity was recorded against Candida spp. The physico-chemical characterization of these two strains MS 9 and MS 10 revealed retention of bioactivity of these metabolites both at low temperature (00C and 40C) and at high temperature up till 700C. Similarly exposure to organic solvents such as ethanol, methanol and formaldehyde also had no effect on their antifungal potential. The findings suggest further purification and possible application of these metabolites as antifungal agent in future. Keywords: Antifungal, Ps. aeruginosa, phytopathogenic fungi, dermatophytes.