Identificação dos compostos bioativos da pitanga do cerrado (Eugenia calycina Cambess) e estudo das suas atividades biológicas

Author(s)

Nayara Macêdo Peixoto Araujo

• Document type: Doctoral Thesis
• Press: Campinas, SP.
• Institution: Universidade Estadual de Campinas (UNICAMP). Faculdade de Engenharia de Alimentos
• Defense date: 2022-04-12

Examining board members

Glaucia Maria Pastore; Iramaia Angelica Neri Numa; Mário Roberto Maróstica Junior; Luiza Helena Meller da Silva; Lucicleia Barros de Vasconcelos

• Advisor: Glaucia Maria Pastore

Abstract

Pitanga of cerrado (Eugenia calycina Cambess) is an unexplored fruit tree native to the Brazilian Cerrado biome that holds high nutritional, functional and economic potential. This plant has been used since ancient times by folk medicine to control diabetes mellitus. Therefore, understanding the chemical composition and biological activities of different botanical parts of Eugenia calycina provides a basis to support future research and applications. In this context, the objective of this study was to extract, characterize and quantify the phytochemicals present in the leaves, pulp and seeds, as well as to evaluate the effects of high-intensity ultrasound (HIUS) on the recovery of these phytochemicals. The LC-MS-based targeted quantitative analysis quantified a total of 18 compounds in all plant parts in which the ellagic acid and myricitrin were the main phenolic compounds found in all parts of the plant. The LC-MS-based untargeted analysis showed the phytochemical profile of the leaves, pulp and seed in which 153 phytochemicals from different chemical classes were annotated, including organic acids, phenolic acids, flavonoids, and other compounds. In the extraction step, the HPST (high power; short process time) treatment showed more efficiency in the recovery of the phenolic compounds. After the extraction, the LC-MS analysis also showed ellagic acid and myricitrin as the main phenolic compounds in all botanical parts evaluated. The interaction of the high nominal power, short processing time, and moderate temperature employed in the HPST extraction procedure positively affected the extraction yield of phenolic compounds from the Eugenia calycina. Based on the results of this step, the pulp was selected to investigate the bioaccessibility of ellagic acid from Eugenia calycina Cambess pulp on simulated gastrointestinal digestion followed by gut fermentation. Also, we evaluated the antidiabetic activity of the gastric phase by means of ?-amylase and ?-glycosidase assays. Ellagic acid was poorly absorbed in the gastric phase (7%) and was observed a slight increase of its release of it in the intestinal phase (9%). Urolithin A was the major catabolites. Volunteers 2 and 3 produced urolithins A and C, while volunteer 1 did not produce urolithins. Urolithins B was not detected independently of volunteers. The production of urolithins A and C in the fecal microflora occurred only after 36h of incubation for volunteers 2 and 3 and their production increased at 48h of fermentation. This study suggests that ellagic acid content and gut microbiota have an important role in the bioaccessibility of the urolithins. In addition, phenolic compounds from Eugenia calycina can be a promising strategy against the inhibition of digestive carbohydrase enzymes (AU)

• FAPESP's process: 18/10608-0 - Identification of bioactive compounds from Pitanga do Cerrado (Eugenia calycina Cambess) and study of its biological activities
• Grantee: Nayara Macedo Peixoto
• Support Opportunities: Scholarships in Brazil - Doctorate