Polysaccharides from acerola, cashew apple, pineapple, mango and passion fruit co-products: Structure, cytotoxicity and gastroprotective effects

Abstract

This study aimed to characterize the chemical structure of water-soluble polysaccharide fractions extracted from co-products of acerola, cashew apple, pineapple, mango and passion fruit, evaluating their gastroprotective effect in vivo associated to their antioxidant activity. The results from the structural analysis revealed that all fractions extracted from the co-products were heteropolysaccharides composed by the monosaccharides glucose, arabinose, galactose and d-galacturonic acid, and presented a pectic nature, which was evidenced by the predominant presence of arabinogalactan in their constitutions. The polysaccharides obtained from acerola, cashew apple and pineapple exhibited similarity in their morphology compared to those from mango and passion fruit. The fractions did not show cytotoxic effects for epithelial culture IEC-6A, and stimulated cell growth as visualized by the increase in cellular viability. Notable antioxidant activities were found for cashew apple (147 μM Trolox.g−1), pineapple (80.0 μM Trolox.g−1) and acerola (79.0 μM Trolox.g−1). These same polysaccharides promoted higher preservation of glutathione levels in mice stomach tissue, resulting in its effective protection from the damage caused by ethanol. On the other hand, high malondialdehyde levels were observed in the stomach tissues of the animals treated with the polysaccharides from mango and passion fruit. The co-products from acerola and cashew were able to protect the gastric mucosa of mice from the lesions induced by ethanol. The results found in this research introduce polysaccharide fractions extracted from acerola, cashew apple and pineapple co-products as safe and natural antioxidants, with a high potential to be applied in different industry fields.