molecules Article Volatilome Analyses and In Vitro Antimicrobial Activity of the Essential Oils from Five South African Helichrysum Species Basma Najar 1,* , Valeria Nardi 1, Claudio Cervelli 2, Giulia Mecacci 1, Francesca Mancianti 3,4 , Valentina Virginia Ebani 3,4, Simona Nardoni 3 and Luisa Pistelli 1,4 1 Dipartimento di Farmacia, Università di Pisa, Via Bonanno 6, 56126 Pisa, Italy;
[email protected] (V.N.);
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[email protected] (L.P.) 2 CREA-Centro di Ricerca Orticoltura e Florovivaismo, Corso Inglesi 508, 18038 Sanremo, Italy;
[email protected] 3 Dipartimento di Scienze Veterinarie, Università di Pisa, Viale delle Piagge 2, 56124 Pisa, Italy;
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[email protected] (S.N.) 4 Centro Interdipartimentale di Ricerca Nutraceutica e Alimentazione per la Salute “Nutrafood”, Università di Pisa, Via del Borgetto 80, 56124 Pisa, Italy * Correspondence:
[email protected] Academic Editors: Francesca Mancianti and Valentina Virginia Ebani Received: 22 June 2020; Accepted: 10 July 2020; Published: 13 July 2020 Abstract: Helichrysum genus was used in folk South African medicine to treat various human disorders. As a part of our on-going research addressing the exploitation of South African plants belonging to this genus, five species were investigated for their volatile and antimicrobial activities. The volatile organic compounds (VOCs) and the essential oils (EOs) were analysed by gas chromatography mass spectrometry (GC-MS). Microdilution was the method used for assessing both antimycotic and antibacterial activities, which was also tested by Kirby-Bauer agar disc diffusion.