Phellinus linteus, a medicinal mushroom with potent antioxidant properties, contains bioactive compounds, such as polyphenols and flavonoids. To optimize the extraction of skin-whitening compounds, ultrasound-assisted extraction combined with statistically based optimization was used to simultaneously extract total polyphenol content (TPC), radical scavenging activity (RSA), and tyrosinase activity inhibition (TAI). Extraction variables, including extraction time (X1:4.8 ~ 55.2 min), extraction temperature (X2:26.4 ~ 93.6oC), and ethanol concentration (X3:13.0 ~ 97.0%), were varied in 17 experimental cycles based on a central composite design. Quadratic regression models for TPC, RSA, and TAI had coefficients of determination (R2) greater than 0.92, demonstrating well-fitted models and statistical significance. Analysis of variance revealed that all three variables significantly influenced extraction efficiency (p < 0.0041), with ethanol concentration (X3) having the most pronounced effect. The optimal extraction conditions were 80.0 min, 82.5oC, and 64.8% ethanol, yielding predicted values of 6.42 mg GAE/g DM for TPC, 73.71% for RSA, and 85.04% for TAI. These results suggest that a moderate ethanol concentration combined with adequate thermal input maximizes the extraction of antioxidant and tyrosinase inhibitory activities specifically associated with skin-whitening effects.
Central composite design was applied for the ultrasound-assisted extraction from peel and seed of Campbell Early grapes and the extraction processes were optimized for the antiradical activities of the extracts by using response surface methodology. Optimal conditions were 53.45% of ethanol concentration, 45.99oC of extraction temperature and 23.93 min of extraction time for the maximum antiradical activity of grape peel extract (54.98%) and 53.14% of ethanol 56.03oC of temperature and 29.03 min of time for maximum antiradical activity of grape seed extract (90.60%).
The effects of ultrasound-assisted extraction (UAE) on the physicochemical and sensory characteristics of coffee beverage were investigated. Coffee powder (4 g) was soaked into 80 mL distilled water and extracted for 15, 30, 60, 120, 180, 240, or 300 sec at 60℃ in an ultrasonic bath (40 kHz, 300 W). Hot-water extraction (HE) at 80℃ for 300 sec was used as a control. Content of soluble solids in coffee beverage prepared by UAE (60~300 sec) was same or higher than those of HE, however, no significant differences were observed among the four beverages extracted for more than 120 sec. Clarity and browning index of beverage prepared by UAE (15 sec) and by HE were significantly higher and lower, respectively, compared to those of the other. Content of phenolic compounds was lower and higher respectively, in beverage prepared by UAE (15 sec, 30 sec) and UAE (60~300 sec) than by HE. DPPH radical scavenging activity was highest in beverage prepared by UAE (15 sec) and HE. Sensory evaluation showed that color, aroma, taste, and overall acceptability were rated with the best score for beverage prepared by UAE (15 sec) and the worst score for beverage prepared UAE (120~300 sec). Therefore, ultrasound-assisted extraction can be used for improving quality of coffee beverage.
The Ponciri fructus immaturus (Poncirus trifoliata Rafinesque) has been used in oriental medicine for uterinecontraction, stomachache, abdominal distension and cardiovascular diseases. Two main compounds, poncirin and naringinwere successfully analyzed by high performance liquid chromatography (HPLC) and carried out method validation accordingto ICH guideline. A successful resolution and retention times were obtained with a C18 reversed phase column, at an 1㎖min−¹ flow rate, with a gradient elution of a mixture of methanol, water and acetonitrile. Poncirin and naringin showed goodlinearity (R²>0.999) in relatively wide concentration ranged. The recovery of each compound was 95.81~101.48% withR.S.D. values less than 1.0%. The application of ultrasound-assisted extraction was shown to be more efficient in extractingponcirin and naringin from Ponciri fructus immaturus. The predicted optimal poncirin and naringin yield were poncirin2.15%, naringin 1.65% under an extraction temperature of 40℃, an extraction time of 10 min in a solvent of 70% methanol.