Inajá and açaí: Study discovers anti-inflammatory power – 08/07/2023 – Science

A doctoral research carried out with inajá and açaí residues, resulting from the pressing of fruit pulp for oil extraction, revealed that they are rich in bioactive compounds with antioxidant and anti-inflammatory activity.

Published in scientific journals Food Research International It is foodsthe results of the study are unprecedented, as these residues had not yet been scientifically investigated.

“Agribusiness activities generate a large amount of waste, often in volumes greater than the product that is sold. An industry that processes fruits for the extraction of oils and other active compounds came to us so that we could study essential oils, at first. Knowing the processing , we suggest investigating the residues, since they have a higher yield than the respective oils at the end of the process and are commonly discarded and unexplored”, says the first author of the articles, Anna Paula de Souza Silva, who is a food scientist and was a fellow of Ph.D. from FAPESP at the Luiz de Queiroz College of Agriculture at the University of São Paulo (Esalq-USP).

According to the researcher, who has been investigating the bioactive potential of açaí and inajá residues, native Brazilian fruits from the Amazon region, since her master’s degree, the literature already reports very important bioactive properties of several other by-products of food processing, such as vegetables and fruits, as well as agricultural ones.

“We saw a great opportunity to study these açaí and inajá residues that, until now, do not have a specific destination, being generally discarded in the environment or destined for animal feed. But, depending on the process, the fruit and its yield in oil , this residue can represent from 60% to 90% of the total volume of raw material”, he reveals.

Flavonoids and anthocyanins

Generally, for the extraction of oils, fruits such as açaí are macerated in hot water, the seeds are removed and the pulp is extracted, dried and pressed.

In the case of inajá, the process is repeated, however, the bark is removed right at the beginning. What is left in the press is called “pie”. Silva carried out an initial characterization of this material and developed extraction methods that enabled the production of an extract rich in antioxidant substances. So he used several methodologies to analyze the properties of the extracts.

“To assess the general antioxidant capacity, we submitted the extracts to an analysis of the content of total phenolic compounds and, subsequently, determined the profile in relation to the bioactive compounds. For this, we separated and identified several compounds by means of high performance liquid chromatography [técnica usada para separar cada um dos componentes de uma mistura] coupled with high resolution mass spectrometry [técnica de detecção e identificação de moléculas pela mensuração de sua massa e que também possibilita a caracterização da estrutura química]”, says the researcher.

“The main compounds identified in the inajá extract were procyanidins and, in the açaí extract, anthocyanins, flavones and flavonoids. We determined for the first time the profile of extracts from these residues, relative to the presence of phenolic compounds. refers to the other activities analyzed, that is, anti-inflammatory, antioxidant and antimicrobial.”

The interdisciplinary group responsible for the work also carried out analyzes related to the sequestration of reactive oxygen species (ROS) – some of which are free radicals that, when present in excess in the body, can cause various types of harm to human health. These oxidants have effects on food as well, for example by shortening its shelf life.

“With very low levels of extracts, we were able to reduce the concentration of some reactive species by 50%. It is an indication that the material has a potent antioxidant action.”

To analyze the anti-inflammatory activity, the researchers treated murine macrophages, which are cells of the immune system of mice, with extracts from açaí and inajá cakes at different concentrations after stimulation with a bacterial compound (lipopolysaccharide or LPS) that triggers an inflammatory process.

After induction, these cells produce NF-κB (a protein complex involved in the cellular response to stimuli, such as stress and the action of free radicals) and cytokines such as TNF-α (with pro-inflammatory actions).

“We evaluated the inhibition of the NF-κB factor and the levels of TNF-α in cells treated with the extracts. The result was quite encouraging. With a concentration of 100 micrograms of extract per milliliter of culture medium [mcg/ml], we were able to inhibit the NF-κB factor, leaving it practically at the level of the cells used as controls, which were not stimulated with inflammatory agents. At this concentration, we were also able to drastically reduce the levels of TNF-α in cells treated with the extracts, also to a value that does not differ from the control”, summarizes Silva.

The group also analyzed the antimicrobial activity of the açaí pie extract, selecting some strains of bacteria and yeasts related to food-borne illnesses and illnesses in hospital environments. “The results indicate a possible antimicrobial action, however, new studies are needed to detail this potential”, says the researcher.

circular economy

Severino Matias de Alencar, one of the authors of the work, states that the group started from identifying the vocation of waste, hence the use of different methodologies of biological and chemical nature.

“We saw that they have antioxidant and anti-inflammatory vocations, indicating a high potential for reuse and contributing to the circular economy, which is what we want.”

Alencar reiterates that açaí and inajá residues are very rich. “Only the oil was removed from there, all the residual material was left. It is a material that can be reused both in the food industry and in the pharmaceutical and cosmetics industry. nothing of animal origin in their products.”

He recalled that Anna Paula Silva also simulated the human digestion of these extracts in vitro, concluding that they retain their anti-inflammatory and antioxidant properties in the intestinal fraction, where they would be absorbed (data in the process of being published).

“Now, we want to study the cellular transport of compounds from the intestinal fraction in a model of human intestinal cells to verify whether the bioactive compounds are absorbed and whether the biological activities are preserved. “, adds the researcher.

The article Inajá oil processing by-product: A novel source of bioactive catechins and procyanidins from a Brazilian native fruit can be accessed at www.sciencedirect.com/science/article/pii/S0963996921002520?via%3Dihu.

The study Phenolic Profile and the Antioxidant, Anti-Inflammatory, and Antimicrobial Properties of Açaí (Euterpe oleracea) Meal: A Prospective Study is available at www.mdpi.com/2304-8158/12/1/8.