Abstract
The consumption of beans has been associated with chronic disease prevention which may be attributed to the polyphenols present in the seed coat and endosperm. However, their bioaccessibility is likely to be limited by interactions with bean matrix components, including starch, protein and fibre. The aim of this project was to evaluate the effect of domestic processing and enzymatic digestion on the bioaccessibility of polyphenols from Borlotti beans (Phaseolus vulgaris) and to test their anti-inflammatory properties in a macrophage cell model. In vitro digestion of cooked beans released twenty times more polyphenols (40.4 ± 2.5 mg gallic acid equivalents (GAE)/g) than domestic processing (2.22 ± 0.1 mg GAE/g), with starch digestion contributing to the highest release (30.9 ± 0.75 mg GAE/g). Fluorescence microscopy visualization of isolated bean starch suggests that polyphenols are embedded within the granule structure. LC-MS analysis showed that cooked Borlotti bean contain flavonoids, flavones and hydroxycinnamic acids, and cooked bean extracts exerted moderate anti-inflammatory effects by decreasing mRNA levels of IL1β and iNOS by 25% and 40%, respectively. In conclusion, the bioaccessibility of bean polyphenols is strongly enhanced by starch digestion. These polyphenols may contribute to the health benefits associated with bean consumption.
Highlights
Common beans (Phaseolus vulgaris) are traditional staple foods in many countries around the world [1,2] and their consumption has been associated with health benefits in both undernourished [3]and overnourished populations [4,5]
Polyphenols were released into the cooking water (2.2 ± 0.1 mg gallic acid equivalents (GAE)/g sample) and the extraction of cooked beans with acidified methanol extracted a further 1.3 ± 0.3 mg GAE/g dry sample
Small amounts of polyphenols were solubilised during soaking and cooking; these polyphenols are likely to originate from the coloured seed coat and may have functions in protecting seeds from environmental stress and pathogen attack
Summary
Common beans (Phaseolus vulgaris) are traditional staple foods in many countries around the world [1,2] and their consumption has been associated with health benefits in both undernourished [3]and overnourished populations [4,5]. Common beans (Phaseolus vulgaris) are traditional staple foods in many countries around the world [1,2] and their consumption has been associated with health benefits in both undernourished [3]. Epidemiological studies suggest that a diet including beans may be protective against cancer [6,7], diabetes [8,9] and cardiovascular diseases [10,11]. In vitro and in vivo studies have shown beneficial effects of bean polyphenols, such as anti-carcinogenic, antioxidant and anti-inflammatory properties [12,13,14]. Domestic preparation of plant foods typically leads to a decrease in antioxidants including polyphenols since these compounds are relatively unstable during thermal processing [15]. Beans are generally soaked and cooked to increase the palatability and to remove anti-nutritional factors such as Nutrients 2020, 12, 295; doi:10.3390/nu12020295 www.mdpi.com/journal/nutrients
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
