In-Vitro Models to Evaluate Biological Effect of Actives

The technology consists of three different advanced in-vitro models for evaluating the biological effect of ingredients or active principles:

• The in-vitro Dynamic Digester that reproduces the physiological conditions of the human gastrointestinal tract (stomach and small intestine) and simulates the gastrointestinal digestion process;
• The in-vitro Digester of Colonic Fermentation that reproduces the gastrointestinal digestion process (stomach, small intestine) as well as the colonic fermentation.
• The DIALFARMA  is an evolution of the Dynamic Digester and incorporates improved features such a physiologically relevant stomach and the differentiation between the three sections of the small intestine, which is of great interest in the evaluation of APIs.

 These in-vitro dynamic models are complemented with cell models that are configured to the biological activity and ingredient to be tested. When necessary, complex models such as co-cultures and the use of microfluidics are applied.

The in-vitro Dynamic Digesters are multi‐compartmental, dynamic and computer‐controlled systems consisting of successive serial compartments simulating stomach and small intestine, and colon. The number of compartments is different depending on the equipment.

The whole system is computer controlled through an operator panel and programmable logic controller (PLC). Temperature control is provided in all compartments, and peristaltic movements are included in the stomach of the DIALFARMA equipment.

Saliva secretions (α‐amylase), gastric secretions (pepsin and lipase), and intestinal secretions (biliary and pancreatic secretion), as well as the corresponding pH conditions, are provided at each compartment by computer‐controlled pumps. The parameters to perform the in-vitro digestion are selected to simulate the gastrointestinal conditions of a healthy human (infant, adult and elderly) after intake of a meal or daily dose. Simulation of the digestion process of monogastric animals is also possible.

The colonic fermentation is achieved after inoculation with a faeces pool and a stabilization period. The microbiota is monitored by both bacterial counts and metagenomics. Metabolomic studies are can also be carried out if necessary.

Cell based models can be independent or coupled to the in vitro dynamic digesters in "integrated models".

Examples of studies that can be carried out with the in-vitro models (dynamic digester/DIALFARMA + cell cultures):

• Evaluation of bioaccessibility of bioactive compounds
• Study the bioaccesibility on intestinal cell model
• Evaluation of the effect of food pre-treatments on bioavailability of nutrients
• Evaluation of gut resistance
• Evaluation of new formulations to improve the absorption of nutrients
• Evaluation of glycaemic index in foods
• Influence of protection techniques (i.e microencapsulation) on bioavailability of bioactive compounds
• In vitro evaluation of bioactive effect by cell models

Examples of studies that can be carried out with the in vitro digester of colonic fermentation:

• Study the interaction between the gut microbiota and food
• Evaluation of gut resistance of bioactive compounds
• Monitorization of the intestinal microbiota colonization
• Evaluation of fermentative properties of bioactive compounds and characterization of microbial metabolites
• Analysis of the composition of the microbial population
• Evaluation of relationship between microbial population and food related pathologies

 Examples of studies that can be carried out with the cell-based models:

• Anti-inflamatory
• Probiotic
• Cholesterol regulation
• Neuroprotective
• Obesity regulator
• Satiating
• Resistence to insuline
• Anti-aging
• Bone health
• Etc.

Clinical trials with humans are the recognised method but they are very expensive. In vitro systems are quick and cost-effective and can serve as first validation screening.

Prior to the commercialisation of a functional food or functional ingredient with health benefits, the in-vitro models can be used to:

1. Validate the gastrointestinal resistance, bioaccessibility and bioavailability of the bioactive compound (in vitro digester models and Caco-2 cell cultures).

2. Validate the bioactive effect on the target organ (cell cultures of the corresponding organs).