RESEARCH ARTICLE In vivo and in vitro control activity of plant essential oils against three strains of Aspergillus niger Peeyush Kumar 1 & Sapna Mishra 2 & Atul Kumar 1 & Sanjeev Kumar 3 & Chandra Shekhar Prasad 4 Received: 27 February 2017 /Accepted: 6 July 2017 # Springer-Verlag GmbH Germany 2017 Abstract Contamination of environment and food from the prevalent spores and mycotoxins of Aspergillus niger has led to several diseases in humans and other animals. The present study investigated the control activity of plant essential oils against three strains of A. niger . In the elaborate assays done through microdilution plate assay and agar disk diffusion as- say in the lab condition and in vivo assay on the stored wheat grains, the essential oil of Thymus vulgaris depicted overall superior efficacy. In microdilution plate assay, the oil of Anethum graveolens showed best fungistatic activity, while best fungicidal activity was depicted by Syzygium aromaticum oil. The oil of T. vulgaris showed moderate control efficacy against A. niger strains with its antifungal activity resulting mainly due to killing of microorganism rather than growth inhibition. In agar disk diffusion assay, T. vulgaris oil with a zone of inhibition (ZOI) of 23.3–61.1% was the most effective fungicide. The in vivo assay to evaluate the protection efficacy of oils for stored wheat grains against A. niger (AN1) revealed T. vulgaris (90.5–100%) to be the best control agent, followed by the oil of S. aromaticum (61.9–100%). The GC–MS anal- ysis of T. vulgaris oil indicated the presence of thymol (39.11%), γ-terpinene (19.73%), o-cymene (17.21%), and β-pinene (5.38%) as major oil components. Phytotoxic effects of the oils on wheat seeds showed no significant phytotoxic effect of oils in terms of seed germination or seedling growth. The results of the study demonstrated control potentiality of essential oils for the protection of stored wheat against A. niger with prospect for development of eco-friendly anti- fungal products. Keywords Aspergillus niger . Essential oils . Environmental toxicity . Fumigation . In vivo assay . Chemical composition Introduction Aspergillus niger , a saprophytic and filamentous fungi, is generally considered as non-toxic with the status of GRAS (generally regarded as safe) by US Food and Drug Administration (Nielsen et al. 2009). Owing to this, A. niger has been widely used in production of several enzymes and organic acids which are commonly used in agro and food industry, as well as in biotransformations and waste treatment (Schuster et al. 2002). However, the potential production of ochratoxin, fumonisin, and afla- toxins by A. niger necessitates the requirement for recon- sideration of its safe categorization. A. niger is pathogen- ic to several fruits, vegetables, cereals, and nuts causing their rotting and decay, while their mycotoxins causes discoloration and deterioration of food products (Kim and Park 2012; Prakash et al. 2015). Moreover, the Responsible editor: Philippe Garrigues Electronic supplementary material The online version of this article (doi:10.1007/s11356-017-9730-x) contains supplementary material, which is available to authorized users. * Peeyush Kumar peeyush0275@yahoo.co.in 1 Division of Seed Science & Technology, Indian Agricultural Research Institute (IARI), New Delhi, Pusa 110012, India 2 Applied Microbiology Laboratory, Centre for Rural Development & Technology, Indian Institute of Technology Delhi, New Delhi 110016, India 3 Centre for Polymer Science, Indian Institute of Technology Delhi, New Delhi 110016, India 4 Biocontrol Laboratory, Sardar Vallabhbhai Patel University of Agriculture & Technology, Modipuram, Meerut, Uttar Pradesh 250110, India Environ Sci Pollut Res DOI 10.1007/s11356-017-9730-x