Contents lists available at ScienceDirect Industrial Crops & Products journal homepage: www.elsevier.com/locate/indcrop Lippia integrifolia: Are there morphological, anatomical and biochemical differences among chemotypes? María Ines Mercado a , Emilio Lizarraga b,c , Victoria Coll Araoz c,d , Cesar Atilio Catalán e , Graciela Font de Valdez f , Guillermo Marcial b,f, * a Instituto de Morfología Vegetal, Área Botánica, Fundación Miguel Lillo, Miguel Lillo 251, S. M. De Tucumán, Argentina b Instituto de Fisiología Animal, Fundación Miguel Lillo, Miguel Lillo 251, S. M. De Tucumán, Argentina c Facultad de Ciencias Naturales e Instituto Miguel Lillo, Universidad Nacional de Tucumán, Miguel Lillo 205, S. M. de Tucumán, Argentina d PROIMI-Biotecnología, CONICET, Av. Belgrano y Pje Caseros, S. M. de Tucumán, Argentina e Química Orgánica II, FBQF, Universidad Nacional de Tucuman, Ayacucho 471, S. M. de Tucumán, Argentina f Centro de Referencia para Lactobacilos (CERELA)-CONICET, Chacabuco 145, S. M. de Tucumán, Argentina ARTICLE INFO Keywords: Lippia integrifolia Chemotypes Flavonoids Phenolic compounds Plant anatomy Histochemistry ABSTRACT Lippia integrifolia, commonly known as “incayuyo”, is a traditional aromatic and medicinal plant that grows wild in northwestern Argentina. Aqueous extracts of this species exert beneficial effects against affections of the gastrointestinal tract, mainly gastric inflammations. Across the wide distribution of L. integrifolia, there is a high variability in the essential oil composition and four chemotypes have been characterized based on the dominant terpenoids in their essential oil composition: trans-nerolidol, lippiafolienone, spathulenol/byciclogermacrene and trans-davanone. In the present work, the morphology, anatomy, chemical constituents and biochemical properties of the aqueous extract of different chemotypes of L. integrifolia were evaluated comparatively. The chemotype whose essential oil is dominated by trans-nerolidol showed significantly higher density of trichomes on the leaves and higher yield in aqueous extractions. Only quantitative variations of dominant metabolites in the aqueous extracts were found among the different chemotypes; those compounds were characterized as 6- methoxyluteolin-O-hexoside, 6-methoxyscutellarein-hexoside, B ring-dimethoxylated flavone-hexoside I, II and lippidulcine-A. In spite of the higher phenolic and flavonoid content, trans-nerolidol chemotype sample pre- sented similar antioxidant properties compared with the other chemotypes. Additionally, the histochemistry of leaves of the trans-nerolidol chemotype was analyzed. The trans-nerolidol chemotype, which grows naturally in the province of La Rioja (Puerto Alegre), presents the best qualities for the medicinal use of the species, due to its higher yield in aqueous extractions and higher phenolic and flavonoid content. 1. Introduction The market of medicinal and aromatic plants is an important eco- nomic resource in many rural areas of Argentina. Among them, the genus Lippia (L.) is widely spread in northwestern Argentina (Mulgura et al., 2012) and many representatives of the genus are frequently used for their medicinal properties. The most outstanding species are L. alba N.E. Br. ex Britton & P. Wilson var. alba and L. turbinata Griseb., which are cultivated for culinary or medicinal purposes (Andersen et al., 2006; Hennebelle et al., 2008; Conde et al., 2011; Leal et al., 2018). These species grow commonly all-around south America, mainly Argentina and Brazil. Within the genus, Lippia integrifolia (Griseb.) Hieron., is a widely distributed herb (Marcial et al., 2016), commonly known as “incayuyo”, “té del Inca”, “yerba-inca” or “inca-yerba”, used for ela- boration of composed “yerba mate” (Scipioni et al., 2007) or for the elaboration of fresh infusions, such as “Termas®”, a natural drink sold in Argentina (http://www.terma.com.ar/productos-regionales.php). Aerial parts (leaves and flowers) are traditionally used in popular medicine to elaborate infusions or decoctions for the treatment of dyspepsia, stomachaches, indigestions, cough and as emmenagogue, diuretic and sedative (Gorzalczany et al., 2008; Alonso, 2015). In recent years, a study by Marcial et al. (2014) demonstrated that aqueous ex- tracts of this species exert beneficial effects against gastritis, which were associated to the anti-adhesive properties against Helicobacter pylori to the mucosal gastric tissue. L. integrifolia and L. boliviana were synonymized based on https://doi.org/10.1016/j.indcrop.2020.112610 Received 20 February 2020; Received in revised form 18 May 2020; Accepted 20 May 2020 ⁎ Corresponding author. E-mail address: gmarcial@cerela.org.ar (G. Marcial). Industrial Crops & Products 153 (2020) 112610 0926-6690/ © 2020 Elsevier B.V. All rights reserved. T