Marine Drugs

Mar. Drugs 2010, 8, 2673-2701; doi:10.3390/md8102673
OPEN ACCESS

Marine Drugs
ISSN 1660-3397 www.mdpi.com/journal/marinedrugs Review

Immense Essence of Excellence: Marine Microbial Bioactive Compounds
Ira Bhatnagar 1 and Se-Kwon Kim 1,2,*
1

2

Department of Chemistry, Pukyong National University, Busan 608-737, Korea; E-Mail: ibhatnagar@gmail.com Marine Bioprocess Research Center,Pukyong National University, Busan 608-737, Korea

* Author to whom correspondence should be addressed; E-Mail: sknkim@pknu.ac.kr; Tel.: +82-51-629-7097, Fax: +82-51-629-7099. Received: 11 September 2010; in revised form: 5 October 2010 / Accepted: 13 October 2010 / Published: 15 October 2010

Abstract: Oceans have borne most of the biological activities on our planet. A number of biologicallyactive compounds with varying degrees of action, such as anti-tumor, anti-cancer, anti-microtubule, anti-proliferative, cytotoxic, photo protective, as well as antibiotic and antifouling properties, have been isolated to date from marine sources. The marine environment also represents a largely unexplored source for isolation of new microbes (bacteria, fungi, actinomycetes,microalgae-cyanobacteria and diatoms) that are potent producers of bioactive secondary metabolites. Extensive research has been done to unveil the bioactive potential of marine microbes (free living and symbiotic) and the results are amazingly diverse and productive. Some of these bioactive secondary metabolites of microbial origin with strong antibacterial and antifungal activities are being intensely used asantibiotics and may be effective against infectious diseases such as HIV, conditions of multiple bacterial infections (penicillin, cephalosporines, streptomycin, and vancomycin) or neuropsychiatric sequelae. Research is also being conducted on the general aspects of biophysical and biochemical properties, chemical structures and biotechnological applications of the bioactive substances derived from marinemicroorganisms, and their potential use as cosmeceuticals and nutraceuticals. This review is an attempt to consolidate the latest studies and critical research in this field, and to showcase the immense competence of marine microbial flora as bioactive metabolite producers. In addition, the present review addresses some effective and novel approaches of procuring marine microbial compoundsutilizing the latest screening strategies of drug discovery.

Mar. Drugs 2010, 8 Keywords: marine microbes; bacteria; fungi; marine natural products; secondary metabolites; bioactivity

2674

1. Introduction Microorganisms, including certain bacteria, fungi and algae, produce secondary metabolites which may have some degree of bioactivity, either against another microorganism or acting againstcertain physiological states of a diseased body. These metabolites, otherwise known as bioactive substances, are profoundly used as antibiotics and may be effective against infectious diseases such as HIV-1 [1]; conditions of multiple bacterial infections (penicillin, cephalosporines, streptomycin, and vancomycin); or neural tube defects and neuropsychiatric sequelae [2,3]. Some drugs have also beenfound to be useful against carcinomas (bleomycin, dactinomycin, doxorubicin and staurosporin), risk of coronary heart disease, or may act as immune-suppressants (cyclosporin) to aid in organ transplantation [4]; thus making the microbial secondary metabolites an enormous source of pharmaceutical importance. Since the 1920s when the first antibiotic Penicillin was discovered, it was believed thatsoil microorganisms are the largest source of novel drugs. It is their biological and chemical diversity, coupled with the underlying competence to produce novel secondary metabolites with antimicrobial and nutritive effects, that has led to the widespread use of microorganisms in the economic, industrial scale production of drugs. The ocean is the mother of life and it is believed that the most...