According to the definition of World Health Organization and Codex Alimentarius Commission, dietary fiber (DF) is constituted by mainly carbohydrate polymers that are neither hydrolyzed in the digestive tract nor absorbed in the small intestine (Codex Alimentarius Commission, 2013). They are widely applied in the food industry as food ingredients to improve the texture and sensory quality of food products. In addition, numerous epidemiological and interventional studies have demonstrated correlations between DF consumption and health benefits (Mayor, 2019; McKeown Jr, Slavin, & Van der Kamp, 2022; Reynolds et al., 2019). DF can be roughly classified into insoluble dietary fiber (IDF) and soluble dietary fiber (SDF) according to their different water solubility. Whole DF is usually a complex mixture of IDF and SDF, however, DF in natural food is rich in IDF (about 70–80%). The increase of SDF content in the whole DF effectively enhanced their physicochemical properties and biological functions, such as water holding capacity (WHC), oil holding capacity (OHC), swelling capacity (SC), cholesterol adsorption capacity (CAC), and glucose dialysis retention index (GDRI) (Hassan, Imran, Ahmad, Khan, & Tarafdar, 2021; Yang et al., 2020; Zheng, Tian, Li, Wang, & Shi, 2021). In addition, SDF has better fecal fermentability than IDF, which is critical in the regulation of gut microbial communities (Gill, Rossi, Bajka, & Whelan, 2021). Moreover, SDF is more adequate in the application of food industry than IDF with better taste and sensory quality. Thus, based on aforementioned beneficial effects of SDF, DFs with higher SDF content were more favorable in food and healthy industry (Ul Ain et al., 2019).

Advanced glycation end products (AGEs) are a group of heterogeneous compounds formed during Maillard reaction (Hellwig & Henle, 2014). Continuous accumulation of AGEs in human body is closely associated with the development of multiple chronic diseases (Chaudhuri et al., 2018). Exogenous AGEs, mainly dietary AGEs, are produced during food thermal processing (Uribarri et al., 2015). DF has been proven to effective in inhibiting AGEs formation during food thermal processing (Deng, Liu, Zhang, Xie, & Huang, 2023). Additionally, dietary AGEs which are not absorbed by the body can increase the intestinal permeability and induce the change of gut microbiota, while the intake of DF can relieve these reverse effects (Snelson et al., 2021).

Bangia fusco-purpurea is a unique red seaweed resource distributed widely on the southeast coast of China with a long edible history in Southeast China and Southeast Asia. Most recently, we found that B. fusco-purpurea polysaccharide, a sulfated galactan, could be fermented by human gut microbiota, and the resultant products showed protective effects on Caco-2 cells from injury induced by lipopolysaccharide (Jiang et al., 2021; Zheng et al., 2022). These biological activities imply that this seaweed has great application potential in the food, biomedicine, and cosmetics industries. However, the lack of deep-processing limited the development of B. fusco-purpurea industry. Dietary fiber (DF), an indigestible carbohydrate of B. fusco-purpurea, is also an important nutrition ingredient in this seaweed. However, there is limited information on the structure and function of DF extracted from this seaweed. Furthermore, changes of dietary fibers during processing of Bangia fusco-purpurea remains unclear, which further restrict the deep-processing and high-value application of this seaweed as a high-quality edible resource.

HPH is an emerging non-thermal food processing technique with promising application potential in seaweed food industry (Vichakshana, Foo, & Choo, 2022). For example, HPH treatment could improve the digestibility, bioaccessibility and bioactivity of compounds from algae (Demarco et al., 2022). HPH treatment of seaweed suspension has been used for the development of seaweed-based edible coating (Kim, Kang, Jo, & Min, 2018) and structuring agents with gel properties in food system (Malafronte et al., 2021). Thus, HPH treatment was applied for the processing of B. fusco-purpurea in this study. Additionally, several studies have reported that HPH can help to convert IDF into SDF and increase the SDF level in whole DF from different plant-based resources, such as sugar beet pulp (Huang, Yang, Liu, & He, 2020), tomato (Hua et al., 2017), citrus (Su, Zhu, Wang, Li, & Wang, 2019), and cabbage (Chen & Wu, 2022). Thus, the effect of HPH treatment on the physicochemical properties, functional properties and in vitro anti-glycation activity of BDF were evaluated. Our findings would provide useful information for the HPH treatment-based deep processing technology of seaweed foods, and further imply that HPH treated B. fusco-purpurea has the potential to be developed as food additives with anti-glycation activity.