http://informahealthcare.com/mby ISSN: 1040-841X (print), 1549-7828 (electronic) Crit Rev Microbiol, Early Online: 1–13 ! 2014 Informa Healthcare USA, Inc. DOI: 10.3109/1040841X.2014.917069 REVIEW ARTICLE Actinobacteria mediated synthesis of nanoparticles and their biological properties: A review Panchanathan Manivasagan 1 , Jayachandran Venkatesan 1 , Kannan Sivakumar 2 , and Se-Kwon Kim 1 1 Department of Chemistry, Marine Bioprocess Research Centre, Pukyong National University, Busan, Republic of Korea and 2 Faculty of Marine Sciences, CAS in Marine Biology, Chidambaram, India Abstract Nanotechnology is gaining tremendous attention in the present century due to its expected impact on many important areas such as medicine, energy, electronics, and space industries. In this context, actinobacterial biosynthesis of nanoparticles is a reliable, eco-friendly, and important aspect of green chemistry approach that interconnects microbial biotechnology and nanobiotechnology. Antibiotics produced by actinobacteria are popular in almost all the therapeutic measures and it is known that these microbes are also helpful in the biosynthesis of nanoparticles with good surface and size characteristics. In fact, actinobacteria are efficient producers of nanoparticles that show a range of biological properties, namely, antibacterial, antifungal, anticancer, anti-biofouling, anti-malarial, anti-parasitic, antioxidant, etc. This review describes the potential use of the actinobacteria as the novel sources for the biosynthesis of nanoparticles with improved biomedical applications. Keywords Actinobacteria, biomedical applications, nanoparticles, nanotechnology History Received 17 March 2014 Revised 17 April 2014 Accepted 17 April 2014 Published online 26 November 2014 Introduction Nanotechnology research is one of the major emerging areas of research with its application in science and technology for the purpose of manufacturing new materials at the nanoscale level (Albrecht et al., 2006). The prefix nano is derived from the Greek word nanos meaning ‘‘dwarf’’ that refers to things of one billionth (10 9 m) in size. The term nanotechnology was coined by Professor Norio Taniguchi of Tokyo Science University in the year 1974 to describe the precision of the industrialized biomaterials at the nanometer level (Taniguchi, 1974). The basic concept of nanotechnology was given by the Physicist, Professor Richard P. Feynman in his lecture There’s plenty of room at the Bottom (Feynman, 1959). Nanobiotechnology has now emerged as an integration between nanotechnology and biotechnology for developing biosynthetic and eco-friendly technology for synthesis of nanomaterials (Rai et al., 2009). Nanoparticles are usually 0.1–1000 nm in each spatial dimension and are commonly synthesized using two strate- gies: top–down and bottom–up (Schirmer, 1999). In the top– down approach, the bulk materials are gradually broken down to nanosized materials whereas in the bottom up approach, atoms or molecules are assembled to molecular structures in nanometer range. Bottom–up approach is commonly used for chemical and biological synthesis of nanoparticles. Advent of nanotechnology has seen scientists, developing protocols for fabricating nanoscale materials and exploring their potential towards a wide range of applications including molecular diagnostics (Cao et al., 2002), catalysis (Pearson et al., 2010), electronics (Schmid & Corain, 2003), drug delivery (Kang et al., 2010), sensing (Nassifab et al., 2004), and surface-enhanced Raman scattering (Plowman et al., 2010). Early phase in the area saw a rise in chemical and physical methods for the synthesis of these technologically important materials with precision in terms of shape, size, and properties. However, the subject of paramount concern in relation to using these materials, for instance, in clinical applications, was raised, due to the use of toxic chemicals, harsh reaction conditions as well as release of harmful byproducts into our environment. Therefore, there is an imperative need to develop a clean, non-toxic, bio-compat- ible, and environmentally benign ‘‘green’’ approach towards synthesizing these materials of technological importance (Bansal et al., 2011; Parikh et al., 2008, 2011). Actinobacteriology is one of the important emerging areas of research in tropics. Actinobacteria are aerobic, non-motile, Gram-positive, often filamentous, bacteria known for their unsurpassed capacity for the production of secondary metab- olites with various biological activities (Zotchev, 2012). Many representatives of the order Actinomycetales are prolific producers of thousands of biologically active secondary metabolites (Manivasagan et al., 2013b). Among the actino- bacteria, streptomycetes group is considered most Address for correspondence: Professor Se-Kwon Kim, Ph.D., Director, Marine Bioprocess Research Center, Department of Chemistry, Pukyong National University, 599-1 Daeyeon 3-dong, Nam-gu, Busan 608-737, Republic of Korea. E-mail: sknkim@pknu.ac.kr Critical Reviews in Microbiology Downloaded from informahealthcare.com by Monash University on 12/04/14 For personal use only.