Abstract In this study, we examined the phytochemical properties and antioxidant activities of the methanol extracts of maca (Lepidium meyenii Walp.) leaves and roots. A total of 25 chemical compounds were identified by LC-Q-TOF and classified as saponins, phenols, flavonoids, steroids, alkybenzenes, and amines. Among all the chemical compounds identified, three saponins (tanshinone I, panaxytriol, and rotundifolioside), one phenol (gingerol), and one steroid (ergosterol peroxide) were found in the both leaf and root extracts. Levels of saponins, phenols, and flavonoids in the methanol extract from maca leaves were significantly higher than in the extract of roots. Antioxidant activities (1,1-diphenyl-2-picrylhydrazyl radical scavenging activity and ferric reducing ability of plasma) of the methanol extracts of maca leaves were higher than those of the roots. Antioxidant activities were highly correlated with total phenol content in the methanol extracts of maca leaves. Therefore, the methanol extract from maca leaves exhibited higher antioxidant activities than those of roots, and could be used as a nutritional material with potential health benefits.

Abstract The objective of this study was to investigate optimized conditions for producing water-in-oil-in-water (W/O/W) microemulsions and spray-dried microcapsules of tomato extracts. The condition of highest yield for W/O/W microemulsification was optimized by response surface methodology (RSM). The independent variables were ratio of tomato extract to MCT (X 1: 1:9-2:8), concentrations of emulsifier (X2: 0.50-1.00), and ratio of W/O to secondary aqueous coating material (X 3: 1:5-1:9). According to the RSM results, the ratio of tomato extract to MCT at 1.24:8.76 (v/v), concentration of emulsifier at 1.00% (w/v), and ratio of W/O phase to secondary aqueous coating material of 1.00:6.16 (v/v) were found to be the optimal conditions for producing microemulsion of tomato extracts. At these conditions, the yield of W/O/W microemulsion determined as approximately 99.69%. After optimizing the conditions for producing microemulsion of tomato extract by RSM, the emulsion was spray-dried. The average particle size ( D(4,3)) and zeta-potential value of the spray-dried microcapsules under optimized condition were approximately 5 µm and -29.68 mV, respectively. Results of the present study provide practical information on optimum conditions for producing W/O/W microemulsions and spray-dried microcapsules of tomato extracts.

Abstract The aim of this study was to optimize conditions for producing water-in-oil-in-water (W/O/W) nanoemulsion and spray-dried nanocapsule of red ginseng extract. Based on emulsion stability and average particle size analysis, optimum conditions to produce W/O/W nanoemulsion were: ratio of core to coating material, 3:7; primary emulsifier, 10% polyglycerol polyricinoleate; ratio of W/O phase to coating material, 1.5:8.5; secondary emulsifier, 10% polyoxyethylene sorbitan monolaurate; solvent, 20% ethyl acetate; secondary coating material, 10% maltodextrin (MD). Under these optimized conditions, particle size of spray-dried nanocapsules coated with MD of red ginseng ranged from 100 nm to 500 nm, based on response surface methodology with the highest yield (up to 99.7%). Results of the present study can be used to further optimize conditions to produce W/O/W nanoemulsion and spray-dried nanocapsule of red ginseng extract.

Abstract The objective of the present study was to investigate the rheological, pasting, and thermal properties of octenyl succinic anhydrate (OSA)-modified potato starch. Potato starch was modified using different concentrations of OSA (0, 1, 3, and 5%, v/v). The degree of substitution (DS) for the OSA-modified starch ranged from 0.0012 to 0.0055. The amylose leaching values of native and OSA-modified potato starch with different DS levels were in the range of 47.09-87.32%. The gel strength values of the OSA-modified starch were lower than those of native potato starch. Rapid Visco Analyzer data showed that peak, hot pasting, final and setback viscosities of the native starch decreased after OSA modification. Dynamic shear rheological tests, conducted at 4 °C, indicated that OSA-modified potato starch had weak gel-like behavior with the storage moduli (G') higher than the loss moduli (G”) over most of the frequency ranges (0.63-63.8 rad·s-1).