Activities of polysaccharide fractions from corn silk: Hemostatic, immune, and anti-lung cancer potentials.

Corn silk is the stigma and style of corn and is rich in polysaccharides. Despite the extensive research on its polysaccharides, the hemostatic characteristics of effective parts and the related activities remain insufficiently explored. Corn silk polysaccharide (CSP) was extracted with hot water and purified using a diethylaminoethyl cellulose membrane. Then, it was separated with sephadex G-150 to obtain five fractions. These fractions were investigated for their potential in hemostasis, antioxidant, immune response, and anti-lung cancer activities. CSP-2, CSP-3, and CSP-4 significantly affected the coagulation indicators activated partial thromboplastin time (APTT) and thrombin time (TT) at 125-500 µg/mL. Corn silk flavonoids and saponins at 32.25 µg/mL significantly prolonged APTT, TT, and prothrombin time (PT). CSP-2, with potent antioxidant ability, approaches Vitamin C. At 25 µg/mL, CSPs nearly reached the phagocytosis of neutral red of lipopolysaccharides. The five fractions promoted the proliferation of RAW264.7 cells at 25-800 µg/mL and stimulated NO secretion at 25-100 µg/mL. CSP-2 also showed an 86 % inhibition rate effect on A549 at 200 µg/mL. These results indicate that CSP not only has hemostatic effects but also has immune and anti-lung cancer activities. Thus, it is a potential candidate compound with immune activity for managing bleeding in cancer.

Flash Extraction, Characterization, and Immunoenhancement Activity of Polysaccharide from Hippophae rhamnoides Linn.

Hippophae rhamnoides L. polysaccharide was optimized with flash extraction by response surface design. The optimum process conditions were: rotation rate 5000 r/min, extraction time 15 s, extraction temperature 90 °C and liquid-to-material ratio 38 mL/g, the extraction yield was 15.28±0.02 %. HRP-1 and HRP-2 obtained by 40 % and 60 % graded alcohol precipitation were characterized. The results indicated that HRP-1 and HRP-2 both composed of mannose, ribose, rhamnose, glucuronic acid, galacturonic acid, glucose, galactose, xylose, arabinose with different molar ratio and the molecular weights were 380.59 kDa and 288.24 kDa, respectively. In addition, the in vitro antioxidant and immunoenhancement activities of HRP-1 and HRP-2 were analyzed, and the two fractions showed good free radical scavenging activity against ⋅OH, ABTS⋅+ , DPPH⋅, and extremely strong immunomodulatory activity against RAW264.7 cells. Indicating that flash extraction is suitable for extraction of HRP, the structural study of HRP provides a scientific theoretical basis for the development of Hippophae rhamnoides.