Enhancing Phenolic Release, Bioaccessibility, and Bioactivity in Selected Legumes Using Steam Explosion and High-Pressure Processing

Friday, Oct. 17, 1-2 p.m.

EN-2043

You are warmly invited to attend the upcoming seminar on Friday, October 17, 2025, hosted by Department of Biochemistry. Please find the details below.

Enhancing Phenolic Release, Bioaccessibility, and Bioactivity in Selected Legumes Using

Steam Explosion and High-Pressure Processing

Sarusha Santhiravel

Ph.D Student

Department of Biochemistry

Memorial University of Newfoundland

October 17th, 2025

1:00-2:00 p.m.

EN-2043

The direct link for the meeting is: https://mun.webex.com/mun/j.php?MTID=m2d8d1bd03b6346aa392989ec7d10d12c

Abstract

There is a rapidly growing interest in natural strategies for chronic disease prevention and overall wellness, driven by concerns over the long-term side effects of synthetic drugs and the global

prevalence of lifestyle-related diseases such as obesity, diabetes, cardiovascular disorders, and certain cancers. Increasing awareness of the link between diet and disease prevention has shifted

consumer preferences toward healthier, natural options. Consequently, there is a rising demand for foods, beverages, and supplements enriched with bioactive compounds, particularly phenolic

compounds. Phenolics are a heterogeneous group of natural substances with diverse health promoting properties, including antioxidant, anti-inflammatory, antidiabetic, cardioprotective, and

anticancer effects. However, in many natural sources, a major fraction of these phenolics is tightly bound within the cell wall matrix, limiting their bioaccessibility and associated health benefits.

This study aimed to evaluate the impact of steam explosion and high-pressure processing on the release and bioaccessibility of phenolics from seeds and hulls of Eston lentils (Lens culinaris

Medik), Dun pea (Pisum sativum sativum var. avense), and beach pea (Lathyrus maritimus (L.) Bigel). Samples were subjected to steam explosion (190 °C, 200 psi, 2 min) and high-pressure

processing (450 MPa, 5 min), followed by extraction of free, esterified, glycosylated, and insoluble-bound phenolics. Total phenolic and flavonoid contents were measured to assess the

release of bound phenolics from the cell wall matrix. Both treatments significantly increased the total phenolic and flavonoid contents of the free phenolic fraction (p < 0.05), while contents of

esterified, glycosylated, and insoluble-bound phenolic fractions decreased.

To evaluate bioaccessibility, samples were subjected to simulated in vitro gastrointestinal digestion, including oral, gastric, small intestinal, and colonic phases. Digesta from each stage

were analyzed for total phenolic content, antioxidant activity, and biological activity using chemical assays and Caco-2 cell models. Compared to untreated samples, both pre-treatment

methods significantly enhanced phenolic bioaccessibility throughout digestion. Notably, steam explosion increased phenolic bioaccessibility in the small intestinal phase by ~45%, while highpressure

processing achieved a ~28% increase. Both treatments also enhanced the scavenging activity of bioaccessible phenolics against peroxyl and hydroxyl radicals. Furthermore, pre-treated

samples exhibited improved antidiabetic potential, protection against oxidative damage to DNA and LDL, and higher cellular antioxidant activity in Caco-2 cells. Phenolic profiling using

UHPLC-TOF-MS/MS revealed ferulic and p-coumaric acids as the predominant phenolicsreleased following both treatments.

Overall, steam explosion proved more effective than high-pressure processing in enhancing the release, bioaccessibility, and bioactive potential of legume phenolics. These findings highlight the

potential of steam explosion as a thermal processing and high-pressure treatment as a non-thermal strategy for valorizing legumes into functional food ingredients or nutraceuticals aimed at

promoting health and reducing disease risk.

We would be delighted to have you join us!

Thank you,

Presented by Department of Biochemistry

Event Listing 2025-10-17 13:00:00 2025-10-17 14:00:00 America/St_Johns Enhancing Phenolic Release, Bioaccessibility, and Bioactivity in Selected Legumes Using Steam Explosion and High-Pressure Processing You are warmly invited to attend the upcoming seminar on Friday, October 17, 2025, hosted by Department of Biochemistry. Please find the details below. Enhancing Phenolic Release, Bioaccessibility, and Bioactivity in Selected Legumes Using Steam Explosion and High-Pressure Processing Sarusha Santhiravel Ph.D Student Department of Biochemistry Memorial University of Newfoundland October 17th, 2025 1:00-2:00 p.m. EN-2043 The direct link for the meeting is: https://mun.webex.com/mun/j.php?MTID=m2d8d1bd03b6346aa392989ec7d10d12c Abstract There is a rapidly growing interest in natural strategies for chronic disease prevention and overall wellness, driven by concerns over the long-term side effects of synthetic drugs and the global prevalence of lifestyle-related diseases such as obesity, diabetes, cardiovascular disorders, and certain cancers. Increasing awareness of the link between diet and disease prevention has shifted consumer preferences toward healthier, natural options. Consequently, there is a rising demand for foods, beverages, and supplements enriched with bioactive compounds, particularly phenolic compounds. Phenolics are a heterogeneous group of natural substances with diverse health promoting properties, including antioxidant, anti-inflammatory, antidiabetic, cardioprotective, and anticancer effects. However, in many natural sources, a major fraction of these phenolics is tightly bound within the cell wall matrix, limiting their bioaccessibility and associated health benefits. This study aimed to evaluate the impact of steam explosion and high-pressure processing on the release and bioaccessibility of phenolics from seeds and hulls of Eston lentils (Lens culinaris Medik), Dun pea (Pisum sativum sativum var. avense), and beach pea (Lathyrus maritimus (L.) Bigel). Samples were subjected to steam explosion (190 °C, 200 psi, 2 min) and high-pressure processing (450 MPa, 5 min), followed by extraction of free, esterified, glycosylated, and insoluble-bound phenolics. Total phenolic and flavonoid contents were measured to assess the release of bound phenolics from the cell wall matrix. Both treatments significantly increased the total phenolic and flavonoid contents of the free phenolic fraction (p < 0.05), while contents of esterified, glycosylated, and insoluble-bound phenolic fractions decreased. To evaluate bioaccessibility, samples were subjected to simulated in vitro gastrointestinal digestion, including oral, gastric, small intestinal, and colonic phases. Digesta from each stage were analyzed for total phenolic content, antioxidant activity, and biological activity using chemical assays and Caco-2 cell models. Compared to untreated samples, both pre-treatment methods significantly enhanced phenolic bioaccessibility throughout digestion. Notably, steam explosion increased phenolic bioaccessibility in the small intestinal phase by ~45%, while highpressure processing achieved a ~28% increase. Both treatments also enhanced the scavenging activity of bioaccessible phenolics against peroxyl and hydroxyl radicals. Furthermore, pre-treated samples exhibited improved antidiabetic potential, protection against oxidative damage to DNA and LDL, and higher cellular antioxidant activity in Caco-2 cells. Phenolic profiling using UHPLC-TOF-MS/MS revealed ferulic and p-coumaric acids as the predominant phenolicsreleased following both treatments. Overall, steam explosion proved more effective than high-pressure processing in enhancing the release, bioaccessibility, and bioactive potential of legume phenolics. These findings highlight the potential of steam explosion as a thermal processing and high-pressure treatment as a non-thermal strategy for valorizing legumes into functional food ingredients or nutraceuticals aimed at promoting health and reducing disease risk. We would be delighted to have you join us! Thank you, EN-2043 Department of Biochemistry