Phytochemical Components and Bioactivity Assessment among Twelve Strawberry (Arbutus unedo L.) Genotypes Growing in Morocco Using Chemometrics

Hafida Zitouni; Lahcen Hssaini; Messaoudi Zerhoune; Hamza Ourradi; Manuel Viuda-Martos; Francisca Hernández; Sezai Ercisli; Hafida Hanine

doi:10.3390/foods9101345

Phytochemical Components and Bioactivity Assessment among Twelve Strawberry (Arbutus unedo L.) Genotypes Growing in Morocco Using Chemometrics

Foods. 2020 Sep 23;9(10):1345. doi: 10.3390/foods9101345.

Authors

Hafida Zitouni¹, Lahcen Hssaini², Messaoudi Zerhoune³, Hamza Ourradi¹, Manuel Viuda-Martos⁴, Francisca Hernández⁵, Sezai Ercisli⁶, Hafida Hanine¹

Affiliations

¹ Laboratory of Bioprocess and Bio-interfaces, Faculty of Science and Technics, University Sultan Moulay Slimane, BO 523 Beni-Mellal, Morocco.
² Research Unit of Plant Breeding and Plant Genetic Resources Conservation, National Institute for Agricultural Research (INRA), BO 578 Meknes, Morocco.
³ Departement of Arboriculture, Horticulture and Viticulture, National School of Agriculture, (ENA), BO S/40 Meknes, Morocco.
⁴ Dpto. Tecnología Agroalimentaria, IPOA, Escuela Politécnica Superior de Orihuela (Universidad Miguel Hernández), Ctra Beniel, km 3.2, E-03312 Orihuela (Alicante), Spain.
⁵ Dpto. Producción Vegetal y Microbiología, Grupo de Investigación de Producción Vegetal y Tecnología, Escuela Politécnica Superior de Orihuela (Universidad Miguel Hernández de Elche), Ctra. de Beniel, km 3.2, E- 03312 Orihuela, Alicante, Spain.
⁶ Department of Horticulture, Agricultural Faculty, Ataturk University, 25240 Erzurum, Turkey.

Abstract

There are not many exhaustive works emphasizing the amount of genetic diversity among the strawberry tree (Arbutus unedo L) genotypes in Morocco. This work aims to assess the biochemical composition of strawberry tree fruits, as well as to establish the variation of this composition among them. In this study, total phenols (TP), total flavonoids (TF), condensed tannins (CT) and hydrolyzable tannins (HT), total anthocyanins (TA), and free radical scavenging activity through ABTS were investigated in strawberry tree fruits. Furthermore, qualitative and quantitative analyses of individual phenolic compounds by high-performance liquid chromatography (HPLC) were carried out. Color parameters such as lightness (L *), Chroma (c *), and hue angle (h°) were also investigated. All studied variables showed highly significant differences among all samples with the exception of hydrolyzable tannins and chromatic coordinates. TP varied from 22.63 ± 1.74 to 39.06 ± 2.44 mg GAE/g DW, TF varied from 3.30 ± 0.60 to 8.62 ± 1.10 mg RE/g DW, and TA ranged between 0.12 ± 0.06 and 0.66 ± 0.15 mg cya-3-glu/100 g DW. In addition, CT and HT amounts were in the range of 10.41 ± 1.07-16.08 ± 1.50 mg TAE/g DW and 4.08 ± 2.43-6.34 ± 3.47 TAE/g DW, respectively. Moreover, the IC50 value (ABTS) ranged between 1.75 and 19.58 mg AAE/g DW. 17 phenolic compounds were detected in strawberry tree fruits. Gallocatechol and catechin were the most abundant phenolic compounds. Matrix of correlations revealed significant positive and negative correlations among variables particularly c *, a *, and b *. Principal component analysis (PCA) showed that the first three components formed than 68% of the total inertia. The following variables gallic acid, protocatechuic, gallocatechin, gallic acid derivative, chlorogenic acid, syringic acid, ellagic acid derivative II, L *, and h * were the most involved in the total variance explained. Hierarchical clustering classified samples into one main cluster, with a single branch. The results highlight a high biochemical diversity within studied strawberry genotypes, which is probably more genetically related.

Keywords: Arbutus unedo L.; Morocco; antioxidant capacity; chemometrics; lolyphenolic compounds.