Bioaccessibility of phenolic compounds using the standardized INFOGEST protocol: A narrative review

Abstract

The INFOGEST protocol creation was a watershed for phenolic bioaccessibility studies. Because of this important initiative to standardize bioaccessibility studies, data comparisons between different laboratories are now expedited. It has been eight years since the INFOGEST protocol creation, and three from the latest update. However, the current status in terms of phenolic bioaccessibility and how far different laboratories are from reaching a consensus are still unrevealed.In this sense, this narrative review considered an evaluation of different studies that applied the INFOGEST protocol to investigate the bioaccessibility of phenolic compounds. The central objective was to compile the main findings and consensus and to identify possible gaps and future opportunities. This approach intends to further facilitate the use of this protocol by professionals in the field of food science and technology and related areas, generating a reflection on the actual level of standardization of the method. Despite the differences in phenolic compounds from diverse food matrices, and their peculiar behavior, some trends could be elucidated, in terms of phenolic release, stability, and/or transformation upon in vivo digestion. In contrast, there was no general consensus regarding sample preparation, how to report results and the form to calculate bioaccessibility, making it difficult to compare different studies. There is still a long road to effectively standardize the results obtained for phenolic bioaccessibility using the INFOGEST protocol, which is also an opportunity in terms of food analysis that can impact the food industry, especially for the development of nutraceuticals and functional foods.

Effect of Gastrointestinal Digestion on the Bioaccessibility of Phenolic Compounds and Antioxidant Activity of Fermented Aloe vera Juices

“…These compounds are bio-transformed again during gastrointestinal digestion, and their content and bioactivity (e.g., antioxidant) can be changed [ 3 ]. Therefore, simulation of in vitro gastrointestinal digestion of food has been widely used to evaluate bioavailability and to study structural changes, release efficiency, digestibility, stability, and bioaccessibility of food nutrients [ 6 , 7 , 8 , 9 ], even if phenolic biotransformation by the gut microbiota is not always performed prior to tests of bioaccessibility and bioavailability.…”

Cocoa powder and fermented jackfruit seed flour: A comparative cell‐based study on their potential antioxidant and anti‐inflammatory activities after simulated gastrointestinal digestion

“…Such loss of activity may be related to the enzymatic activities and pH changes during the simulated digestion process that leads to degradation and/or precipitation of phenolic compounds, especially for anthocyanins, which are present in the Nac, hampering their biological activities. 51 The anti-inflammatory activity of Fjs may be related to the presence of prenylated flavonoids and Moracin C, a compound of the benzofuran class previously found in jackfruit. These compounds were previously attributed to the reduction of several antiinflammatory parameters, including TNF-⊍ levels.…”

“…We note that after the simulated digestion process there was a potential decrease in parameters such as NF‐κB activation and TNF‐α levels. Such loss of activity may be related to the enzymatic activities and pH changes during the simulated digestion process that leads to degradation and/or precipitation of phenolic compounds, especially for anthocyanins, which are present in the Nac, hampering their biological activities 51 …”

Valorization of pineapple (Ananas comosus) by-products in milk coffee beverage: Influence on bioaccessibility of phenolic compounds

“…The increase in antioxidant potential observed during the intestinal phase may be attributed to the generation of new oxidation products, exhibiting greater antioxidant activity than their precursors. Additionally, it could also result from the presence of other antioxidant molecules that are not phenolic compounds [15]. The bioaccessibility values varied between 53-87% and 78-112% according to DPPH and CUPRAC assays, respectively.…”

“…To address this issue, INFOGEST developed a standardized static model to simulate digestion in the upper gastrointestinal tract [13,14]. Although the INFOGEST in vitro digestion model has previously been employed to investigate how digestion of different food items affects the bioaccessibility of phenolic compounds [15], to the best of our knowledge no previous study has investigated the effect of the addition of pineapple by-products on the bioaccessibility of coffee phenolics using the in vitro digestion model of INFOGEST.…”