Reclaiming Agriceuticals from Sweetpotato (Ipomoea batatas [L.] Lam.) By-Products.

Sweetpotato (SP, Ipomoea batatas [L.] Lam.) is a globally significant food crop known for its high nutritional and functional values. Although the contents and compositions of bioactive constituents vary among SP varieties, sweetpotato by-products (SPBs), including aerial parts, storage root peels, and wastes generated from starch processing, are considered as excellent sources of polyphenols (e.g., chlorogenic acid, caffeoylquinic acid, and dicaffeoylquinic acid), lutein, functional carbohydrates (e.g., pectin, polysaccharides, and resin glycosides) or proteins (e.g., polyphenol oxidase, ß-amylase, and sporamins). This review summarises the health benefits of these ingredients specifically derived from SPBs in vitro and/or in vivo, such as anti-obesity, anti-cancer, antioxidant, cardioprotective, and anti-diabetic, evidencing their potential to regenerate value-added bio-products in the fields of food and nutraceutical. Accordingly, conventional and novel technologies have been developed and sometimes combined for the pretreatment and extraction processes aimed at optimising the recovery efficiency of bioactive ingredients from SPBs while ensuring sustainability. However, so far, advanced extraction technologies have not been extensively applied for recovering bioactive compounds from SPBs except for SP leaves. Furthermore, the incorporation of reclaimed bioactive ingredients from SPBs into foods or other healthcare products remains limited. This review also briefly discusses current challenges faced by the SPB recycling industry while suggesting that more efforts should be made to facilitate the transition from scientific advances to commercialisation for reutilising and valorising SPBs.

Digestion & fermentation characteristics of sulfated polysaccharides from Gracilaria chouae using two extraction methods in vitro and in vivo.

The sulfated polysaccharides extracted from Gracilaria chouae using critic acid extraction and water extraction, respectively, and their digestion and fermentation characteristics were compared in vitro and in vivo. The molecular weight of water extracted polysaccharide of G. chouae (WGCP) was 1.73 × 103 kDa while critic acid extracted polysaccharide (CGCP) was 31.5 kDa. During stimulated gastrointestinal digestion in vitro, WGCP and CGCP were lightly degraded. However, the glycemic index (GI) of WGCP and CGCP were 17.7 and 36.12, respectively. After 24 h of fermentation in vitro, the pH values of CGLP in the fecal culture decreased from 6.89 to 4.82, similar to the inulin but significantly (p < 0.05) lower than those of the WGCP and normal control. In addition, CGCP and inulin showed similar microbial fermentation characteristics according to the microbiome compositions and contents of short-chain fatty acids (SCFAs). Nevertheless, CGCP gavage for four weeks could also promote the growth of microbes producing the SCFAs such as Peptococcus, Roseburia and Butyricicoccus in the cecum of KM mice. The present study suggests that polysaccharides prepared by acid-extraction method could potentially be used as a good source of prebiotics.

Effect of Curcumin Addition on the Properties of Biodegradable Pectin/Chitosan Films.

A pectin/chitosan matrix-loaded curcumin film (PCCF) with a deep eutectic solvent (DES) as the solvent and plasticizer was prepared in this study. Different quantities of curcumin (identified as PCCF-0, PCCF-1, PCCF-2. PCCF-3) were loaded on the pectin/chitosan film in order to evaluate their effects on the film properties. Results showed that curcumin could interact with the pectin/chitosan matrix and form a complex three-dimensional network structure. PCCF could promote the thickness, tensile strength, thermal properties, antioxidant and antiseptic capacities, but deteriorate the light transmission and elongation at the same time. The addition of curcumin would change the color of the film, without significantly affecting the moisture content. The tensile strength of PCCF-3 reached the maximum value of 3.75 MPa, while the elongation decreased to 10%. Meanwhile, the water-resistance properties of PCCF-3 were significantly promoted by 8.6% compared with that of PCCF-0. Furthermore, PCCF showed remarkable sustained antioxidant activities in a dose-dependent manner. PCCF-3 could inhibit DPPH and ABTS free radicals by 58.66% and 29.07%, respectively. It also showed antiseptic capacity on fresh pork during storage. Therefore, curcumin addition could improve the barrier, mechanical, antioxidant and antiseptic properties of the polysaccharide-based film and PCCF has the potential to be used as a new kind of food packaging material in the food industry.