Cassava flour (CF) was used as a raw material to replace wheat flour (WF) at levels of 0% (control), 10%, 20%, 30%, 40%, and 50% to prepare wheat–cassava composite flour (W-CF) and dough. The effects of different CF substituting levels on the functional properties of the W-CF and dough were investigated. The results show that an increase in CF led to a decrease in the moisture, protein, fat, and b* values of W-CF. The crude fiber, ash, starch, L*, a* values, iodine blue value (IBV), and swelling power (SP) of the composite flour increased gradually. It was found that the water absorption, hardness, and chewiness of the W-CF dough increased with an increase in the CF substitution level. A different trend could be observed with the springiness and cohesiveness of the W-CF dough. The resistance to extension, extensibility, and the extended area of the W-CF dough at all substitution levels was significantly lower than that of the WF dough. The elasticity and cohesiveness of the dough tended to increase for CF content from 10% to 30%, followed by a decrease at a higher replacement. Pearson correlation analysis indicated that the substitution levels of CF had a significant influence on the proximate analysis and functional properties of the W-CF and dough. This study will provide important information on choosing CF substitution levels for different products.

Polysaccharides from hemp seeds exhibit antioxidant activities in vitro and in vivo. However, crude polysaccharide quality is often low owing to the presence of fibres and pigment impurities, which are difficult to eliminate in the hemp seed shell. In this study, crude polysaccharides from hemp kernels (HKP) were obtained by hot water extraction and separated by membrane ultrafiltration into eight fractions with different molecular weights. Total antioxidant capacity and free radical scavenging (DPPH) assays were performed to evaluate the antioxidant activities of HKP and the fractions in vitro. The structural characteristics of HKP were determined using various analytical techniques. The Fe³⁺-reducing power of HKP was 7.65 ± 0.22 μmol/g, and HKP possessed the highest DPPH radical-scavenging rates (94.30 ± 2.27%), similar to 5 mg/mL Vitamin C (Vc), which had a rate of 95%. The HKP was an acidic polysaccharide with a low molecular weight (4.21 ± 0.12 kDa). The monosaccharide composition indicated that HKP primarily comprised mannose, ribose, glucuronic acid, galacturonic acid, glucose, galactose, arabinose, and fucose in a molar ratio of 0.96:1.95:8.27:0.98:9.46:1.69:6.10:2.82. The molar mass of HKP was distributed widely in a triple helical conformation. This study provides a scientific basis for further research on the use of hemp polysaccharides.

This study aimed to screen out polysaccharides with the ability to activate NK cells. Ten polysaccharides (OP) were isolated from orah mandarin (Citrus reticulata cv. Orah) peel using hot-water extraction combined with the alcohol precipitation method and the ultrafiltration-membrane separation method. After measuring the effects of 10 OPs on NK-92MI cell proliferation and cytotoxicity, it was found that the polysaccharide OP5 had the highest activity in vitro. OP5 can significantly promote the proliferation of and increase the gene expression of perforin, granzyme B and IFN-γ in NK-92MI cells. Its molecular weight was between 50 and 70 kDa. The identification results of monosaccharide composition indicated that OP5 was composed of arabinose (31.52%), galacturonic acid (22.35%), galactose (16.72%), glucose (15.95%), mannose (7.67%), rhamnose (2.39%), fucose (1.41%), xylose (1.30%), glucuronic acid (0.42%) and ribose (0.27%). The sugar ring of the β-configuration was the main, and that of the α-configuration was the auxiliary. These results would provide a foundation for the functional product development of OPs.