A comparative characterization of proteins from three edible insects—Tenebrio molitor (mealworm) larvae, Gryllus bimaculatus (cricket), and Bombyx mori (silkworm) pupae—was performed in this study. Proteins were extracted from edible insects and their hydrolysates were prepared through enzymatic hydrolysis with commercial enzymes (Flavourzyme: 12%; Alcalase: 3%). Solubility was significantly higher following enzymatic hydrolysis, while foamability was lower compared to those of the protein control. Angiotensin-converting enzyme was significantly inhibited after enzymatic hydrolysis, especially following Alcalase treatment, with IC50 values of 0.047, 0.066, and 0.065 mg/mL for G. bimaculatus, T. molitor larvae, and B. mori pupae, respectively. Moreover, the Alcalase-treated group of B. mori pupae and the T. molitor larvae group treated with a mixture of enzymes showed the effective inhibition of α-glucosidase activity. The anti-inflammatory activity of the insect hydrolysates was assessed via nitric oxide production from macrophages, and B. mori pupae samples exhibited significant activity regardless of the method of hydrolysis. These results indicate the functional properties of protein and hydrolysates from three species of edible insects, which may be useful in their future exploitation.
Amylose-lipid complex (ALC) was prepared with corn starch and stearic acid and used as a shortening replacement in white pan bread preparation. ALCs were prepared using various concentrations of stearic acid to corn starch (1%, 3%, 5%, and 7%) under different temperatures (55, 65, and 75 °C) and for different durations of time (30, 60, and 120 min); then, their complexing properties were assessed using iodine reagent and X-ray diffraction. The complexing reaction at 75 °C for 60 min showed the highest complexing index of the tested conditions; the in vitro digestibility of ALC was lower than that of corn starch. White pan bread was prepared with ALCs and their characteristics, including appearance, loaf volume, and starch retrogradation during storage at room temperature for four days, were compared with those of control bread. With increasing ALC replacement concentrations, loaf volume and shape were significantly affected; however, starch retrogradation was significantly retarded and energy value decreased by ALC replacement. Overall, 50% replacement of shortening by ALC appeared to be a reasonable level for retaining the basic characteristics of the bread while retarding the staling process. These results indicate that ALCs may be potentially useful in the bakery industry for preparing low calorie and low-fat products.
14 November 2013 in Journal of Agricultural and Food Chemistry
UV irradiation exposure may induce photoaging of the skin tissue. Various plant extracts have been recognized as effective protectants against UV-induced damage. Here, a mixture of marigold and rosemary extracts was evaluated for its anti-photoaging effects as a potential nutraceutical product for skin health. Hexane extract of marigold and ethanolic extract of rosemary were prepared, and the formulated mixture was investigated. A UV-induced photoaged mouse model was prepared, and the protective effects of the extract mixture were compared with those of hyaluronic acid (positive control). Expression of various photoaging-related biomarkers such as matrix metalloproteinases (MMPs), interleukins, tumor necrosis factor-alpha, procollagen type I, 8-hydroxy-deoxyguanosine, superoxide dismutase, glutathione peroxidase, and catalase were determined. UV irradiation significantly enhanced the expression of these biomarkers through an inflammatory response, however, the mixture of marigold and rosemary extracts exerted inhibitory effects and protected from UV-induced damage. Suppression of inflammatory response were the mechanisms underlying this protective function of the mixture of marigold and rosemary extracts. Histological evaluation also supported these protective effects against photoaging.
27 July 2014 in Journal of the Korean Society for Applied Biological Chemistry