(P06-047-23) A Supplemental Mixture of Microbial Proteases Enhances Peptide and Amino Acid Release From Plant Proteins Under Simulated Gastric Conditions

Objectives: Dietary protein supplementation has been shown to increase resistance exercise-induced muscle mass, strength, and recovery from workouts. Digestive enzyme supplementation is a candidate approach to further improve anabolic effects of dietary protein, in particular plant proteins that generally show reduced digestibility compared to dairy proteins. The objective of this study was to determine the efficacy of OPTIZIOME® P<sup>3 HYDROLYZER^TM (P3), a mixture of three microbial proteases obtained from Aspergillus species, on the digestion of plant proteins in the INFOGEST in vitro static simulation of gastric digestion.

Methods: Briefly, the INFOGEST protocol includes a 2 min salivary phase with porcine amylase and a 120 min gastric phase with porcine pepsin (the 120 min intestinal phase with porcine pancreatin was not included in this study). In the treatment groups, P3 was mixed with protein substrates (250 mg P3 per 25 grams of protein) to reflect its use in bulk protein powder products. Substrates included food-grade brown rice protein concentrate (BRP), hemp heart protein concentrate (HHP), mung bean protein concentrate (MBP), and pumpkin seed protein concentrate (PSP). All gastric simulations were performed in triplicate. To determine the proteolytic effects of P3, the free amino nitrogen (FAN) concentrations of gastric digestas were measured by spectrophotometry. Gastric digestas were also analyzed for molecular weight distribution by size exclusion chromatography (SEC).

Results: Following simulated salivary-gastric digestion of BRP, the FAN concentrations of gastric digestas were 39.6% higher with P3 treatment compared to pepsin-only controls (P < 0.0001). With HSP, MBP, and PSP, the FAN concentrations of gastric digestas were 15.0%, 18.0%, and 20.6% higher with P3 treatment compared to controls (P = 0.0020, P = 0.0013, P = 0.0002, respectively). Corroborating the FAN data, SEC analysis of gastric digestas demonstrated a distribution of less high-molecular weight peptides and more low-molecular weight peptides and amino acids with P3 treatment across all plant protein substrates.

Conclusions: These in vitro data support the use of supplemental microbial proteases to enhance plant protein digestion. Future experimentation will include profiling of free essential amino acids and BCAAs in gastric digestas by HPLC.

Funding Sources: BIO-CAT, Inc.