In vitro digestion of polysaccharides: InfoGest protocol and use of small intestinal extract from rat

Being widely abundant, grass proteins could be a novel source of plant proteins for human foods. In this study, ryegrass proteins extracted using two different approaches-chemical and enzymatic extraction, were characterised for their physico-chemical and in vitro digestion properties. A New Zealand perennial ryegrass cultivar Trojan was chosen based on its higher protein and lower dry matter contents. Grass protein concentrate (GPC) with protein contents of approximately 55 and 44% were prepared using the chemical and enzymatic approach, respectively. The thermal denaturation temperature of the GPC extracted via acid precipitation and enzymatic treatment was found to be 68.0 ± 0.05 °C and 66.15 ± 0.03 °C, respectively, showing significant differences in protein’s thermal profile according to the method of extraction. The solubility of the GPC was highly variable, depending on the temperature, pH and salt concentration of the dispersion. The solubility of the GPC extracted via enzymatic extraction was significantly lower than the proteins extracted via the chemical method. Digestion of raw GPC was also studied via a gastro-small intestinal in vitro digestion model and was found to be significantly lower, in terms of free amino N release, for the GPC prepared through acid precipitation. These results suggest that the physico-chemical and digestion characteristics of grass proteins are affected by the extraction method employed to extract the proteins. This implies that selection of an appropriate extraction method is of utmost importance for achieving optimum protein functionality during its use for food applications.

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In vitro digestion under simulated saliva, gastric and small intestinal conditions and fermentation by human gut microbiota of polysaccharides from the fruits of Lycium barbarum

International Journal of Biological Macromolecules ◽

10.1016/j.ijbiomac.2018.12.081 ◽

2019 ◽

Vol 125 ◽

pp. 751-760 ◽

Cited By ~ 26

Author(s):

Yu Ding ◽

Yamei Yan ◽

Yujia Peng ◽

Dan Chen ◽

Jia Mi ◽

...

Keyword(s):

Gut Microbiota ◽

In Vitro Digestion ◽

Human Gut ◽

Lycium Barbarum ◽

Human Gut Microbiota ◽

Small Intestinal

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In Vitro Study for Lipolysis of Soybean Oil, Pomegranate Oil, and Their Blended and Interesterified Oils under a pH-Stat Model and a Simulated Model of Small Intestinal Digestion

Nutrients ◽

10.3390/nu11030678 ◽

2019 ◽

Vol 11 (3) ◽

pp. 678 ◽

Cited By ~ 2

Author(s):

Chenming Ji ◽

Jung-Ah Shin ◽

Soon Hong ◽

Ki-Teak Lee

Keyword(s):

Soybean Oil ◽

In Vitro Study ◽

In Vitro Digestion ◽

Molar Ratio ◽

Simulated Model ◽

Interesterified Oil ◽

Intestinal Digestion ◽

Ph Stat ◽

Small Intestinal

In this study, two in vitro digestion models were employed to compare the rate of lipolysis in soybean oil (SBO), pomegranate oil (PGO), a physical blend (PHY, 1:1 molar ratio of SBO:PGO, w/w), and their enzymatically interesterified oil (IO). In the pH-stat digestion model (emulsified oils with bile salts), PGO emulsion containing 74.7% conjugated form of linolenic acid (CLn) showed a significantly lower release rate of free fatty acid (FFA) than the other oil emulsions (p < 0.05). In FFA release rates and oil droplet sizes between PHY and IO emulsions, no significant differences were observed (p > 0.05). In a simulated model of small intestinal digestion, the lipolysis rates of SBO, PGO, PHY, and IO after digestion for 30 min in digestion fluids were 80.4%, 66.5%, 74.8%, and 77.0%, respectively. The rate of lipolysis in PGO was significantly lower than that in SBO (p < 0.05), and the lowest lipolysis rate was observed in the conjugated form of trilinolenoyl glycerol (CLn-CLn-CLn).

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