**1. Introduction**

*Rhus coriaria* L., generally known as sumac, is a typical plant native of a large area spreading from the Canary Islands over the Mediterranean coast to Iran and Afghanistan. Its name originates from "sumaga," which means red in Syriac [1].

Among the sumac species, *R. coriaria* L. has the greatest economic importance. In Sicily, this Asian species was first imported by the Arabs; on this island, it grows spontaneously and acquires surprising nutritional characteristics determined by the pedoclimatic conditions [2].

*R. coriaria* is a high shrub or small tree (1–3 m high) with imparipinnate leaves, villose and red fruits with one-seeded drupe, and small greenish-white flowers organized in panicles [3].

**Citation:** Lo Vecchio, G.; Cicero, N.; Nava, V.; Macrì, A.; Gervasi, C.; Capparucci, F.; Sciortino, M.; Avellone, G.; Benameur, Q.; Santini, A.; et al. Chemical Characterization, Antibacterial Activity, and Embryo Acute Toxicity of *Rhus coriaria* L. Genotype from Sicily (Italy). *Foods* **2022**, *11*, 538. https://doi.org/10.3390/ foods11040538

 Academic Editor: Manuel Viuda-Martos

Received: 27 December 2021 Accepted: 8 February 2022 Published: 14 February 2022

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Several studies have been carried out in order to identify the major components of the *R. coriaria* plant's different parts [3], its bioactive molecules [4], and its fatty acid composition [5]. However, only few studies have been conducted on Sicilian sumac [6,7], and in particular on its drupes, which are the main endpoints of the proposed study.

Since ancient times, given its nutritional value and its phytochemical components (flavonoids, flavones, anthocyanins, tannins, organic acids, fiber, proteins, volatile oils, nitrites, and nitrates), it has been used both as a spice by mashing and mixing the dehydrated fruits with salt and as a medicinal herb [7,8]. Its ordinary state is a fruit, and, to date, it is economically attractive because of its growing use in several biotechnological applications, from the nutraceutical and food sectors, to cosmetic and pharmaceutical industries as well as in veterinary practices, and in dying leather [3,4,6,9,10].

The *R. coriaria* components, including fatty acids, minerals, fiber, and phytochemicals, are responsible for its several beneficial properties. Its nutritional value makes this plant interesting as a food fortifier or functional food [6]. Its antimicrobial and antioxidant properties make this plant a promising tool as a food preservative [3,11,12]. In addition, its coloring properties and tannins are used in dying and tanning fine leather. The bioactive compounds, which are responsible for antioxidant, antilipidemic, antimicrobial, antiviral, antifungal, and anti-inflammatory activity [11–14], also make this plant an interesting tool for the pharmaceutical sector.

To date, there is no study investigating the antimicrobial activity of Sicilian sumac, and although several studies have reported on the antimicrobial activity of *R. coriaria* [15–17], the proposed study is novel, adding information to the area of interest.

In order to investigate all the promising potential of Sicilian sumac, in the present study, a full characterization of this fruit is reported, including the proximate composition determination, the phenolic and anthocyanin content, and the mineral content. A preliminary comparative antibacterial screening of different sumac extracts was carried out, and its non-toxicity was proven by using the Zebrafish Embryo Toxicity Test (ZFET). Further studies are in progress to have a better understanding of this plant genotype and its possible biotechnological applications.

#### **2. Materials and Methods**

#### *2.1. Reagents and Chemicals*

Heptane, methanol, ethanol, and acetone were supplied by PanReac AppliChem (Barcelona, Spain) and J.T. Baker (Phillipsburg, NJ, USA). Ultrapure water (18 m Ω cm resistivity and <5 ppb TOC) was produced by a Barnstead Smart2Pure 12 Water Purification System (Thermo Scientific, Milan, Italy). Reference standards of fatty acids methyl esters (FAMEs, C4–C24) and stock standard solutions of inorganic elements (1000 mg/L in 2% HNO3) were obtained from Supelco (Bellefonte, USA). Sugars and polyphenol standards were obtained from Extrasynthese (Genay, France) and Sigma-Aldrich (St. Louis, MO, USA). The Kjeldahl catalyst was supplied by Carlo Erba (Milan, Italy). Methanol, standard gallic acid, cyanidin-3-O-glucoside, and Folin–Ciocalteau reagen<sup>t</sup> were obtained from Sigma-Aldrich (Steinheim, Germany). PTFE syringe filters (0.45 μm) were purchased from Gelman Sciences Inc. (Ann Arbor, MI, USA). High purity water with a resistivity of 10 m Ω cm, nitric acid trace metal analysis grade, and hydrogen peroxide were acquired from J.T. Baker (Milan, Italy). Stock standard solutions of B, Mg, Na, Al, K, Ti, Cr, Mn, Fe, Zn, Ni, As, Sr, Ba, Pb, and Bi (1000 mg/L in 2% nitric acid) were purchased from Fluka (Milan, Italy). The Cd solution (1000 mg/L in 2% nitric acid) and the Hg solution (1000 mg/L in 3% hydrochloric acid) were obtained from Merck (Darmstadt, Germany). MeOH HPLC grade, quercetin, and gallic acid standards were obtained from Sigma-Aldrich (St. Louis, MO, USA).
