Interactional, functional, and biological properties of lactone sophorolipid (LSL) and collagen oligopeptides (COP) in aqueous solution.

For the mixed aqueous solution of LSL and COP, the interaction mode and mechanism have been comprehensively studied using multispectral methods including fluorescence spectrum, ultraviolet-visible (UV-vis )adsorption spectra, and circular dichroism (CD) spectra. The surface activity, particle size, foaming, emulsifying, viscosity, and antibacterial properties were evaluated in detail using a surface tension measurement (ST), dynamic light scattering (DLS), oscillometric method, spectrophotometer, Ubbelohde viscometer, and zone of inhibition separately. Compared with the single LSL or COP aqueous solution, the mixed system shows different performance optimizations in different aspects. The surface activity and foaming properties are mainly attributed to LSL, and the viscosity is attributed to COP. Fluorescence spectroscopy results show using LSL addition that the fluorescence distribution of COP has significant changes and a static quenching mechanism was proved. The results of UV-vis and CD spectra also show the changing conformation of COP using LSL addition. Data on thermodynamic parameters demonstrated that the combination of LSL and COP gives a spontaneous exothermic process and is an enthalpy-driven process. The interaction mechanism between LSL and COP is very helpful for the application and development of the mixed mild biosurfactant-protein system used in the cosmetic and food industries.

Anti-tumor activity evaluation of novel chrysin-organotin compound in MCF-7 cells.

Chrysin (5,7-dihydroxylflavone, Chry) is a natural flavonoid extracted from plants and propolis. In this work, a novel chrysin-organotin (Chry-Sn) compound with enhanced anticancer activities was synthesized by the reaction of chrysin and triphenyltin chloride, and its potential anticancer effects against cancer cells were measured using various methods. Sulforhodamine B (SRB) results showed that chrysin and Chry-Sn had significant inhibition effects on the proliferation of MCF-7, A549 and HeLa human cancer cell lines in a dose- and time- dependent manner. These results suggested that Chry-Sn possessed enhanced anticancer effects. Hoechst 33258 staining and acridine orange staining results showed apoptosis and nuclei fragments significantly increased after being treated with chrysin and Chry-Sn respectively. Moreover, chrysin and Chry-Sn significantly increased ROS levels in MCF-7 cells. Western blot results showed that chrysin and Chry-Sn activated caspase 3 and induced autophagy by increasing LC3-II level. All results showed collectively that Chry-Sn could be a more promising drug than chrysin in anticancer treatment.