Nanocrystalline Cellulose Cures Constipation via Gut Microbiota Metabolism.

Constipation can seriously affect the quality of life and increase the risk of colorectal cancer. The present strategies for constipation therapy have adverse effects, such as causing irreversible intestinal damage and affecting the absorption of nutrients. Nanocrystalline cellulose (NCC), which is from natural plants, has good biocompatibility and high safety. Herein, we used NCC to treat constipation assessed by the black stool, intestinal tissue sections, and serum biomarkers. We studied the effect of NCC on gut microbiota and discussed the correlation of gut microbiota and metabolites. We evaluated the long-term biosafety of NCC. NCC could effectively treat constipation through gut microbiota metabolism, which required a small dosage and did not affect the organs and intestines. NCC could be used as an alternative to medications and dietary fiber for constipation therapy.

Polypyrrole decorated BiOI nanosheets: Efficient photocatalytic activity for treating diverse contaminants and the critical role of bifunctional polypyrrole.

A conducting polymer polypyrrole (Ppy) was first employed to decorate BiOI for fabricating an organic-inorganic hybridized Ppy-BiOI nanocomposite photocatalyst via a facile in situ precipitation strategy at room temperature. The composite and intimate interface was confirmed by FTIR, XPS, SEM, HRTEM and TEM-mapping. In comparison with pristine BiOI, the Ppy-BiOI hybrids present significantly enhanced photocatalytic activity for degradation of Rhodamine B (RhB) under visible light (λ>420nm). Particularly, the Ppy-BiOI composite exhibits an universal photocatalytic performance for removing diverse industrial pollutants and antibiotics, including bisphenol A, 2,4-dichlorophenol, tetracycline hydrochloride and chlortetracycline hydrochloride. The enhanced photocatalytic activity of Ppy-BiOI composite is found attributable to the bifunctional role that Ppy takes. Ppy-BiOI composite has an enhanced specific surface area, which benefits adsorption and generation of more active sites. Notably, high separation and transfer of the photogenerated charge carriers was achieved on the interface between Ppy and BiOI, and the photogenerated hole transfer action of Ppy is demonstrated. Therefore, synergistic effect of adsorption-enrichment and photocatalytic degradation is realized. Our work may offer a guideline to manipulate high-performance Bi-based composite photocatalyst by coupling conducting polymers.