A bioaccessible fraction of parboiled germinated brown rice exhibits a higher anti-inflammatory activity than that of brown rice

Abstract

Parboiled germinated brown rice (PGBR) has been suggested as a functional food because it is relatively rich in a number of nutrients and health promoting compounds. Here we compared the bioaccessibility of several of the bioactive compounds in cooked PGBR and brown rice (BR) by simulating oral, gastric and small intestinal digestion. The uptake and retention of bioactive compounds from a bioaccessible fraction also was determined using Caco-2 human intestinal cells. The anti-inflammatory activity of the bioaccessible fraction from digested BR and PGBR was then assessed with Caco-2 cells that were activated with H2O2 + IL-1β. PGBR had a higher content of GABA, γ-oryzanol, γ-tocotrienol, ferulic acid and p-coumaric acid than BR. The amounts of these compounds transferred to the aqueous fraction during digestion and the quantities accumulated by Caco-2 cells were proportional to those in cooked PGBR and BR. The anti-inflammatory activity of the bioaccessible fraction from digested BR and PGBR was then assessed for Caco-2 cells that were activated with H2O2 + IL-1β. Pre-treatment of the cells with the bioaccessible fractions from PGBR and BR suppressed the secretion of IL-8 and MCP-1 and the ROS content in activated cells. Inhibitory activities were attenuated to a greater extent after cells had been pre-exposed to the bioaccessible fraction from digested PGBR compared to BR. These results suggest that digested PGBR contains and delivers greater amounts of compounds with anti-inflammatory activity to absorptive epithelial cells than digested BR.

Pre-germinated brown rice extract ameliorates high-fat diet-induced metabolic syndrome

“…Pre‐germinated brown rice (PGBR), a popular rice in Taiwan with rice‐removed husk, bran, and germ, is proved to be better than white rice, because it is rich in nutrients, such as γ‐oryzanol, γ‐aminobutyric acid (GABA), and dietary fibers (Roohinejad et al, ). γ‐oryzanol and GABA improve the levels of blood biochemical parameters in metabolic syndrome (Roohinejad et al, ; Tuntipopipat et al, ; Wunjuntuk, Kettawan, Charoenkiatkul, & Rungruang, ). Dietary fibers' intake also prevents obesity and controls metabolic syndrome (Reverri et al, ).…”

Promising industrial flour processing and household applications of parboiled germinated brown rice (Khao dok mali 105)

“…Individual g-oryzanol, a-tocopherol, a-tocotrienol, g-tocopherol and g-tocotrienol samples were qualitatively analysed according to Srichamnong, Thiyajai, Charoenkiatkul (2015). The analysis was performed by HPLC with an LC pump, an SIL injector, a photodiode array and a fluorescence detector (Agilent, California, US).…”

“…After harvesting, the rice sample was cleaned by removing of immature and damaged grains by following a normal industry protocol. Then, the rice was pre-germinated and parboiled according to Srichamnong, Thiyajai and Charoenkiatkul (2015). In short, 500 g of rice was soaked in water for 18 h. The water was changed every 4 h in order to minimize microbial growth.…”

“…Extraction was performed according to the method described by Srichamnong, Thiyajai and Charoenkiatkul (2015). In short, 2 g of rice flour was mixed with 30 mL of methanol and MeOH: hexane (50:50) for g-oryzanol and tocol extraction in a capped test tube.…”

“…Germinated brown rice has been recognised as nutritious rice. In addition, the parboiled germinated brown rice (PGBR) contains and delivers greater amounts of bioactive compounds with anti-inflammatory activity on absorptive epithelial cells than brown rice (Tuntipopipat et al, 2015).…”