Optimization of novel single-step gelatin extraction method using RSM model for valorization of surimi industry by-products

Surimi industry produces large quantity of by-products as a combination of skin, bones, and scale, which due to technical difficulty in separation, are being currently utilized for production of low- value products such as biofertilizers and fish feed. Present paper focuses on utilization of combined skin, bones, and scale from Pink Perch (Nemipterus japonicus) obtained from surimi industry for gelatin extraction using single step process. Single step extraction method with acetic acid and water was optimized using Response Surface Methodology (RSM) to maximize yield and gel strength so that the process can be applied for sustainable utilization. Parameters such as pH (A), extraction temperature (B) and extraction time (C) with respect to yield and L-hydroxyproline content were optimized. Highest gelatin yield was obtained at pH 3, 75°C extraction temperature, and 30 min extraction time. Gelatin yield and L-hydroxyproline content under optimum condition were 16.2% and 41.62 mg.g−1. The chemical composition, functional, rheological, and structural properties of gelatin were examined and compared with commercial bovine gelatin. Gelatin thus obtained at optimized condition exhibited high gel strength (793g) and higher imino acid content (18.1%) than bovine gelatin. FTIR spectra depicted high similarities between both gelatin sample. Thus, the optimized method can be utilized for gelatin extraction from Pink Perch by-products for development of high value products such as food application.

Extraction of Polyphenols from Olive Leaves Employing Deep Eutectic Solvents: The Application of Chemometrics to a Quantitative Study on Antioxidant Compounds

The extraction of phenolic compounds from olive leaves was optimized using three glycerol-based deep eutectic solvents (DESs) with lysine, proline, and arginine. A three-level Box–Behnken design was used to examine the influence of the liquid/solid ratio, concentration of DESs, and extraction temperature on the yield of the extraction process. A second-order polynomial model was used for predicting the polyphenol extraction yield. The optimal predicted conditions were used for extractions and they provided the highest total phenol yields with the glycerol–lysine exhibiting the best performance. Quantification of tyrosol, hydroxytyrosol, oleuropein, luteolin-7-O-glucoside, and rutin in the extracts showed high content in tyrosol in all DESs, particularly with glycerol–lysine and relatively similar contents with other studies for the other phenolic compounds. Finally, a linear relationship between tyrosol content and the total phenolic content of the extracts was observed.

Effects of Artificial Sweat Formulation and Extraction Temperature on Estimation of the Dermal Bioaccessibility of Potentially Toxic Elements in a Contaminated Soil from an E-Waste Recycling Site

Informal recycling of electronic waste leads to soil contamination that can impact human health. To accurately assess exposure to potentially toxic elements (PTE) in soil it is necessary to consider their bioavailability through ingestion, inhalation and dermal contact. However, bioaccessibility tests that estimate dermal absorption following adhesion of contaminated soil particles to skin are not well established. In this study the concentrations of As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn were estimated in the <45 µm particle size fraction of a bulk composite soil from an e-waste recycling site using five different artificial sweat formulations. Extractions were performed at temperatures ranging from 17 to 47 °C to investigate the effect of ambient temperature on bioaccessibility. Results obtained using the different artificial sweats were not consistent with one another. In particular, the NIHS 96-10 formulation solubilized larger amounts of analytes (ranging from 6.3 times the next most effective extractant for Cu to 1700 times the next most effective for Pb). There was a general increase in release of PTE with increasing temperature, except for As. Although trends varied between analytes and formulations, this highlights the need to consider ambient temperature when estimating dermal bioaccessibility of PTE in soil.

Response Surface Optimization for Antioxidant Extraction and Attributes Liking from Roasted Rice Germ Flavored Herbal Tea

The optimal process conditions when examining the antioxidant potential, total polyphenol content, and attribute liking in roasted rice germ flavored herbal tea were investigated using response surface methodology (RSM). The influence upon the extraction process of time and temperature was assessed using a full factorial design on three levels with two variables (32), involving five central point replicates. Extraction temperature (70 °C, 80 °C, and 90 °C) and extraction time (3 min, 4.5 min, and 6 min) served as independent variables, while the dependent variables were allocated to the regression equation to determine antioxidant activity (R2 = 0.941) along with total polyphenol content (R2 = 0.849), flavor liking score (R2 = 0.758), and overall liking score (R2 = 0.816). Following experimentation, it was determined that the optimal time and temperature conditions to maximize total polyphenol content, antioxidant activity, flavor, and overall liking score were in a range of 86 °C to 90 °C for 3.4 min to 5.9 min. When these conditions were imposed, the antioxidant potential, total polyphenol content, flavor, and overall liking score were >70% for DPPH scavenging activity, >75 mgGAE/g, >6.7 (like moderately), and >6.5 (like moderately), respectively.

Reflux Extraction Optimization and Antioxidant Activity of Phenolic Compounds from Pleioblastus amarus (Keng) Shell

Phenols were extracted from the Pleioblastus amarus (Keng) shell (PAS) using ethanol. A Plackett–Burman assessment indicated that the factors affecting polyphenol extraction included the ethanol concentration, extraction temperature, liquid to solid ratio, extraction time, and reflux extraction times; the best extraction parameters were the ethanol concentration of 75%, a 20:1 liquid to solid ratio, and an extraction time of 2.1 h. The number of polyphenols was 7.216 mg/g. Furthermore, the phenol composition analysis showed the presence of p-Coumaric acid (196.88 mg /mL) and rutin (312.9 mg /mL), which were used for the in vitro extraction and determination of the antioxidant activity. According to the A, B, C, and D antioxidant activity assays, the ethyl acetate phase was the strongest with low IC50 values of 0.169 ± 0.01 mg/mL, 0.289 ± 0.01 mg/mL, 0.372 ± 0.01 mg/mL, and 1.029 ± 0.03 mg/mL, respectively, confirming high antioxidant activity. For the n-butanol and petroleum ether phases, antioxidant activity was lower. This study showed that the polyphenol extract from Pleioblastus amarus (Keng) shell displayed excellent antioxidant activity, enhancing its practical application.

Optimization of Emprit Ginger Oil Yield through Operating Temperature with Microwave Ultrasonic Steam Diffusion Method

<h1><em>Essential oil of ginger (zingiberene oil (C₁₅H₂₄)) is one of the diversified products that have high selling value. Most of the essential ginger products available in the market haven’t allow the standard export products, based on the Essential Oil Association of USA (EOA) standards. The low quality of ginger essential oil products is due to its production process with conventional distillation. This method is most often used because it is easy to operate and produce a good enough product but takes a long time. Another extract method developed is Microwave Distillation and Simultaneous Solid-Phase Microexctraction (MDSS- PM). In this method the time required is faster but the resulting product is not as good as Hydrodistillation product and requires high energy. In this research, ginger extraction process using Microwave Distillation method is modified by ultrasonic addition technique (MUSDf). The variables used in this research are Steam Diffusion (SDF) method, Microwave Exctraction (ME), Microwave Steam Diffusion (MSDf), Microwave Ultrasonic Steam Diffusion (MUSDf) with 30, 50,70, 90 and 110 minutes extension time and extraction temperature variations of 90, 95, 100 and 1050C. From the result of the research, it is found that the best method to produce ginger oil extract is by using MUSDf method with yield of 0.952%, zingiberene level is 6.38%, and the cost per gram of oil is Rp 17,964.</em></h1>

Modelling of Liquid-Liquid Equilibria Using NRTL and UNIFAC Equations in the Extraction of Bio-Oil-Based Phenolics Produced from the Pyrolysis of Sugarcane Bagasse

An exploration on renewable energy resources has been paid more attention due to the depletion of the fossil-based energy resource. In addition, their safe and environmentally friendly properties have attracted experts’ interest. One of the renewable energy resources is the bio-oil produced from sugarcane bagasse. The bio-oil was produced through a pyrolysis at 500°C. However, the produced bio-oil showed a high content of phenolics, c.a. 40-60%. A liquid-liquid extraction to remove the phenolics using methanol-chloroform solvents would be beneficial to improve the stability of the bio-oil as well as to obtain high purity phenolics. Modelling of the liquid-liquid equilibria in the extraction was then developed using NRTL and UNIFAC equations. The empirical quantitative data of phase equilibrium system were calculated on both the extract and raffinate phases. The lowest RMSD value of 0.043160 was obtained from the calculations using NRTL equation at an extraction temperature of 50°C. Thus, the most suitable model was achieved using NRTL equation.

Response Surface Methodology (RSM)-Based Optimization of Ultrasound-Assisted Extraction of Sennoside A, Sennoside B, Aloe-Emodin, Emodin, and Chrysophanol from Senna alexandrina (Aerial Parts): HPLC-UV and Antioxidant Analysis

In this study, ultrasound-assisted extraction conditions were optimized to maximize the yields of sennoside A, sennoside B, aloe-emodin, emodin, and chrysophanol from S. alexandrina (aerial parts). The three UAE factors, extraction temperature (S1), extraction time (S2), and liquid to solid ratio (S3), were optimized using response surface methodology (RSM). A Box–Behnken design was used for experimental design and phytoconstituent analysis was performed using high-performance liquid chromatography-UV. The optimal extraction conditions were found to be a 64.2 °C extraction temperature, 52.1 min extraction time, and 25.2 mL/g liquid to solid ratio. The experimental values of sennoside A, sennoside B, aloe-emodin, emodin, and chrysophanol (2.237, 12.792, 2.457, 0.261, and 1.529%, respectively) agreed with those predicted (2.152, 12.031, 2.331, 0.214, and 1.411%, respectively) by RSM models, thus demonstrating the appropriateness of the model used and the accomplishment of RSM in optimizing the extraction conditions. Excellent antioxidant properties were exhibited by S. alexandrina methanol extract obtained using the optimized extraction conditions with a DPPH assay (IC50 = 59.7 ± 1.93, µg/mL) and ABTS method (47.2 ± 1.40, µg/mL) compared to standard ascorbic acid.

Selecting optimal parameters for obtaining the extract of red grape pomace

Due to the industrial processing of grapes, large amounts of by-products are produced. The main varieties of by-products are pomace, which is comprised of skins, seeds and any other solid remaining after pressing process and sediments. It is necessary to implement new effective ways of processing to minimize these residues. This problem is relevant for all the wine-producing countries, including Georgia. It is well-known fact that pomace is an important source of phenolic compounds, which are characterized by high antioxidant activity and possess healing-prophylactic properties. It is also worth mentioning that pomace is an easily spoiled product, and without the proper processing, it cannot be stored for a long time. Thus, this research aimed to obtain optimal parameters for extraction, preserving the antioxidant characteristics. The optimal range of the following parameters for extraction was determined: the temperature for drying 45-50 °C, grinding level 1.5 mm, diluent concentration 70% ethanol/water solvent, extraction module 1:20, extraction temperature 50-55 °C, and duration 2 h. This determination of technological parameters of extraction was done according to the best physical-chemical measures and antioxidant activity level. The physical-chemical tests were performed according to the European Union standards. These parameters can produce an extract with distinct antioxidant characteristics that can be used in the food industry as a natural antioxidant. The extract with distinct antioxidant properties was obtained, which can be used in the food industry as a natural antioxidant.

Physical and Mechanical Behaviors of Red Sandstones and Marbles after High-Temperature Treatment

Deep geothermal energy is of great strategic importance for the development of the energy industry. In the process of geothermal energy extraction, temperature changes will significantly affect the physical and mechanical properties of the rock mass. To investigate the influence of temperature on the physical and mechanical properties of red sandstones and marbles, the uniaxial compression test, variable-angle shear test, mercury intrusion porosimetry (MIP) test, and SEM test were conducted on the red sandstone and marble specimens treated by 9 temperature levels (from 25°C to 800°C). The results show that the porosity is positively correlated with the temperature regardless of rock types. The peak strength of red sandstones during uniaxial compression increases first when temperature increases from 25°C to 400°C and then decreases when temperature increases from 400°C to 800°C, whereas the peak strength of marbles exhibits a first decreasing (from 25°C to 300°C), then increasing (from 300°C to 600°C) and finally decreasing (from 600°C to 800°C) trend. Similarly, the shear strength and cohesion of red sandstones increase first and then decrease as temperature rises from 25°C to 800°C, despite of the predesigned shearing angle, which is opposite to the variation in frictional angle. The variations in physical and mechanical behavior are closely related to the expansion of the constituent grains or groundmass which make up the rock composition and closure of pores. Additionally, the temperature in the range from 400°C to 600°C plays an important role to evaluate the variations in the physical and mechanical characteristics of red sandstones and marbles after high-temperature exposure, because of the stress, strain, and porosity change dramatically.