In vitro antifungal efficacy of copper nanoparticles against selected crop pathogenic fungi Prachi Kanhed a , Sonal Birla a , Swapnil Gaikwad a , Aniket Gade a , Amedea B. Seabra b , Olga Rubilar c,d , Nelson Duran e,f , Mahendra Rai a,n,1 a Department of Biotechnology, SGB Amravati University, Amravati 444 602, Maharashtra, India b Universidade Federal de São Paulo – Unifesp, Diadema, São Paulo, Brazil c Chemical Engineering Department, University of La Frontera, PO Box 54-D, Temuco, Chile d Scientific and Technological Bioresource Nucleus, University of La Frontera, PO Box 54-D, Temuco, Chile e Center of Natural and Human Sciences, Universidade Federal do ABC, SP, Brazil f Institute of Chemistry, Biological Chemistry Laboratory, Universidade Estadual de Campinas, Campinas, SP, Brazil article info Article history: Received 26 July 2013 Accepted 1 October 2013 Available online 10 October 2013 Keywords: Copper nanoparticles Antifungal Plant pathogen FTIR TEM abstract Copper nanoparticles play an important role in the field of optics and electronics, and also as a novel antimicrobial. In the present study, we report antifungal activity of copper nanoparticles against selected crop pathogenic fungi. Copper nanoparticles were synthesized by chemical reduction of Cu 2 þ in the presence of Cetyl Trimethyl Ammonium Bromide and isopropyl alcohol. Characterizations of copper nanoparticles were carried out by UV–visible spectroscopy, nanoparticles tracking analysis (NTA), Fourier transform infrared spectroscopy (FTIR) and transmission electron microscopy (TEM) which revealed that synthesized nanoparticles were coated by Cetyl Trimethylammonium Bromide (CTAB) having particle size of 3–10 nm. Copper nanoparticles demonstrated significant antifungal activity against plant pathogenic fungi: Phoma destructiva (DBT-66), Curvularia lunata (MTCC no. 2030), Alternaria alternata (MTCC No. 6572) and Fusarium oxysporum (MTCC No. 1755). Since for the synthesis of copper nanoparticles the present chemical method by using C-TAB-IPA is found to be simple, economic and fast, the synthesized copper nanoparticles can be used as a novel antifungal agent in agriculture to control the plant pathogenic fungi as well as potent disinfectant in poultry and animal husbandry. & 2013 Elsevier B.V. All rights reserved. 1. Introduction The present century is an emerging era of nanotechnology, which comprises capacity to alter the structure of a molecule at atomic level. The most important invention of nanotechnology is the metallic nanoparticles having superior property to that of its bulk structure. Metallic nanoparticles exhibit significantly improved phy- sical, chemical and biological properties. Due to the altered struc- ture, metal nanoparticles possess superior optical [1], electronic [2], magnetic [3], thermal [4], catalytic [5] and sensing [6] functional- ities. Among different noble metals, copper is one of the promising metals. Moreover, the copper nanoparticles (CuNPs) have received an increasing attention due to their high thermal and electrical conductivity, lubrication, catalyst and low cost possessions [7]. Copper nanowires have also proved to be an efficient next genera- tion electric device. The stable and monodispersed biological synth- esis of CuNPs is difficult due to the rapid oxidation of copper. Several methods like sonochemical [8], photolytic [9], chemical reduction [10] and microemulsion techniques [11] have been available for synthesis of copper metal and their oxides nanoparticles. There are some reports of biogenic synthesis of copper nanoparticles [12–16] as well as copper and their complexes as antimicrobial activity has been widely used since ancient time [17]. In 1761 for the first time copper was used in agriculture when it was discovered that seed grains soaked in a weak solution of copper sulfate inhibit the seed- borne fungi. Among inorganic antimicrobial agents, copper com- pounds have been used widely in agriculture practices as fungicide [18], pesticide [19], algaecide [20], and herbicide [21] as well as in animal husbandry as a disinfectant [22]. Biogenic CuNPs showed good activity against Escherichia. coli [23,15]]. Bordeaux and bur- gundy were used to control the downy-mildew in garden, nursery, vineyard and in farm. From then onwards copper fungicides have Contents lists available at ScienceDirect journal homepage: www.elsevier.com/locate/matlet Materials Letters 0167-577X/$- see front matter & 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.matlet.2013.10.011 n Corresponding author. Tel.: þ91 721 2662207/8x267; fax: þ91 721 2660949/2662135. E-mail addresses: prachikanhed20@gmail.com (P. Kanhed), nisha14586@gmail.com (S. Birla), gaikwad.swapnil1@gmail.com (S. Gaikwad), aniketgade@rediffmail.com (A. Gade), amedea.seabra@gmail.com (A.B. Seabra), duran@iqm.unicamp.br (N. Duran), gaikwadswapnil@rediffmail.com, mkrai123@rediffmail.com, pmkrai@hotmail.com (M. Rai). 1 Presently Visiting Scientist, Institute of Chemistry, Biological Chemistry Laboratory, Universidade Estadual de Campinas, Campinas, SP, Brazil. Materials Letters 115 (2014) 13–17