In this study, ultrasound-assisted extraction of green pea pod polysaccharide (GPPP) was investigated and optimized using a central composite response surface design coupled with a numerical optimization technique. The effects of ultrasonic power (50–150 W), sonication time (20–80 min), ratio of water to raw material (20:1–40:1 mL/g) and extraction temperature (40–80 °C) on polysaccharide extraction yield were studied. The maximum extraction yield was obtained with a sonication power of 135.34 W, extraction time of 48.61 min, ratio of water to raw material of 33.6:1 mL/g and extraction temperature of 68.25 °C. Under these conditions, the experimental yield was 7.37% ± 0.13%, which was in close agreement with the predicted value (7.20%). The GPPP has been analyzed in order to identify a variety of chemical properties. The FT-IR spectrum demonstrated obvious characteristic peaks of polysaccharides. Furthermore, antioxidant activity of GPPP was evaluated by various antioxidant assays in vitro. The results revealed that GPPP possessed considerable DPPH free radical scavenging activity (91.03%), reducing power (0.63) and ferric reducing antioxidant power (0.34 mmol/L) at a total amount of 0.9 mg/mL. These findings indicated that GPPP extracted using an ultrasound-assisted extraction technique has potential as a novel source of natural antioxidant agent for future applications.

Microwave-assisted extraction (MAE) is an effective green extraction method of value-added and bioactive compounds. The impact of different extraction times (2-7 min), microwave power (360-760 W), and solvent-to-sample ratio (20 : 1-40 : 1 ml/g) on the extraction yield of Ocimum basilicum var. album L. using MAE was investigated. Maximum extraction yield ( %) was obtained at optimal conditions for extraction using response surface methodology, including extraction time of 4.33 min, power of 570.32 W, and the solvent-to-sample ratio of 40 : 1 ml/g, which was very close to the model prediction (17.01%). The yield of the conventional extraction (CE) method (50°C, 100 rpm, 1 h extraction time, and solvent-to-sample ratio of 40 : 1 ml/g) was %. Comparisons were made between the functional and structural characteristics of the mucilage extracted under optimal conditions and the CE method. Fourier transforms infrared (FTIR) spectroscopy was utilized to study the changes in functional groups, and scanning electron microscopy (SEM) was used to determine the morphological characteristics. Emulsion stability against heat, water absorption capacity, foaming capacity, and foaming stability of the extracted mucilage under optimal conditions were %, g/g, %, and %, respectively, which were higher than the CE method. SEM results showed a more porous structure in mucilage obtained by the MAE method, while no changes were observed by FTIR analysis between the functional groups of extracted mucilage obtained from the utilized extraction methods. Therefore, the application of the MAE method was superior to CE in terms of yield, structural and functional characteristics, and significantly shorter extraction time. The findings show the great potential of microwave processing in commercial and laboratory extraction of mucilage without deteriorative effects on the structural and functional properties of the extracted material.

The current study investigated the effect of rice bran protein isolate (RBPI), in the amounts of 0, 1, 2, and 3% of wheat flour, which are mentioned in abbreviate as C, RBPI1, RBPI2, and RBPI3, respectively, on qualitative and bioactive properties of sponge cake. The results indicated that RBPI contains 57.58% protein with high pepsin digestibility (87.95%). RBPI addition increased the consistency (Bostwick number) and specific gravity (SG) of the prepared batter samples from 7.62 cm and 1.08 for the control to 6.50 cm and 1.14 for RBPI3, respectively. The protein content of sponge cake increased significantly from 6.31% (C) to 6.95% (RBPI3), but the cake volume and baking loss decreased significantly ( ) with increasing the amount of RBPI. The crust color of the cake samples was changed ( and were decreased, and was increased) by RBPI addition. The texture profile analysis (TPA) and sensory evaluation demonstrated that up to 2% of wheat flour can be replaced by RBPI without negatively affecting the characteristics of these. Total phenol content (TPC) and DPPH scavenging activity of RBPI2 were also improved. According to the results obtained from all the evaluations, the addition of RBPI to up to 2% of wheat flour is recommended to improve the qualitative and bioactive properties of the prepared functional sponge cake.