Optimum Ultrasound-assisted Extraction Conditions Research Articles

Characterization of Cichorium intybus L. Extract in Preventing Oxidative DNA Base Damage Using Gas Chromatography–Tandem Mass Spectrometry (GC–MS/MS)

Free radicals are unstable and are known for electron deficiency. This state renders DNA, proteins, and various biomolecules susceptible to detrimental interactions, leading to damage. However, this process can be regulated by antioxidants produced naturally on-site or externally through food or herbal supplements. In recent years, interest in characterizing alternative, natural and safe antioxidants obtained from plant sources has been increasing. Within this context, Cichorium intybus L. has garnered attention for its notable antioxidant content. In our previous study, we determined optimum conditions for ultrasound-assisted extraction of antioxidants from Cichorium intybus L. using central composite design-response surface methodology. In this study, the quantitative determination of phenolics in the extract prepared under optimal conditions was undertaken employing high-performance liquid chromatography with diode array detection (HPLC-DAD). The study’s primary goal is to investigate the impact of the extract derived from Cichorium intybus on the formation of products resulting from oxidative damage to DNA bases by gas chromatography–tandem mass spectrometry (GC–MS/MS). For this purpose, different volumes of extract were added to the DNA + Fenton medium. When 25 µL of extract were added, 239.98 ± 5.81 ng of damaged product/mg DNA was present. 233.12 ± 5.63 ng of damaged product/mg DNA were obtained for 50 µL of extract and 165.76 ± 4.58 ng of damaged product/mg DNA for 100 µL. This study shows that Cichorium intybus has potential therapeutic effects on supporting antioxidant defenses and reducing oxidative DNA damage.

Optimization of Ultrasound Assisted Extraction (UAE) Conditions on Vitamin C from Roselle Flower

Roselle plant (Hibiscus sabdariffa L.) has many benefits. Vitamin C is an antioxidant in which the human body required. It contains a high amount of vitamin C. However, vitamin C is susceptible to high temperatures. Proper extraction treatment conditions produce optimum vitamin C. This study aims to determine the optimization of vitamin C in rosella flowers. This research uses UAE with Qsonica type – Q500 (500 W, 20 kHz). Extraction treatment conditions control amplitude, time and amount of solvent. The research method used is a laboratory experiment with the RSM (Response Surface Methodology) type CCD (Central Composite Design) approach. The research method was an experimental laboratory using a CCD (Central Composite Design) via RSM (Response Surface Methodology) with an amplitude level from 20% to 50%, a time level from 10 minutes to 20 minutes, and a ratio of the amount of solvent from 140 mL to 260 mL by weight. The results showed that the length of time and the amount of solvent had a significant effect, while the amplitude had no significant effect. The significant quadratic model at p value 0.05 and R2 0.9221 with optimum UAE conditions in the treatment combination of 50 percent amplitude, 20 minutes of time, and 140 ml of solvent resulted in an optimum vitamin C content of 38.76 mg/100g. This research can be used as a reference to determine the value of vitamin C with different amplitude, time, and amount of solvent from the research data.

Optimization of Pluchea indica (L.) leaf extract using ultrasound-assisted extraction and its cytotoxicity on the HT-29 colorectal cancer cell line

Colorectal cancer (CRC) is the most common malignancy and the third primary cause of cancer-related mortalities caused by unhealthy diet, hectic lifestyle, and genetic damage. People aged ≥ 50 are more at risk for CRC. Nowadays, bioactive compounds from plants have been widely studied in preventing CRC because of their anticancer and antioxidant properties. Herein, ultrasound-assisted extraction (UAE) was used to extract the bioactive compounds of Pluchea indica (L.) leaves. The resultant total phenolic content (TPC) and total flavonoid content (TFC) of P. indica (L.) leaves were analyzed using a response surface methodology (RSM). The central composite design was implemented to evaluate the amplitude (10 %–70 %) and treatment time (2–10 min) on both responses, i.e., TPC and TFC of P. indica (L.) leaves. The optimum UAE conditions were observed 40 % amplitude and 6 min of treatment, where the TPC and TFC were 3.26 ± 0.00 mg GAE/g d.w. and 67.58 ± 1.46 mg QE/g d.w., respectively. The optimum P. indica (L.) leaf extract was then screened for its cytotoxicity on the HT-29 colorectal cancer cell line. This extract had strong cytotoxicity with a half-maximal inhibitory concentration value (IC50) of 12 µg/mL. The phytochemical screening of bioactive compounds revealed that the optimal P. indica (L.) leaf extract contains flavonoids, namely, kaempferol 3-[2′'',3′'',5′''-triacetyl]-alpha-L-arabinofuranosyl-(1->6)-glucoside, myricetin 3-glucoside-7-galactoside, quercetin 3-(3′'-sulfatoglucoside), and kaempferol 7,4′-dimethyl ether 3-O-sulfate, which could be good sources for promising anticancer agents. This study employs the RSM approach to utilize UAE for bioactive compounds extraction of P. indica (L.) leaves, identified the specific compounds present in the optimized extract and revealed its potential in preventing CRC.

Ultrasound-Assisted Extraction of Hydroxytyrosol from Lactiplantibacillus plantarum Fermented Olive Leaves: Process Optimization and Bioactivity Assessment

Olive leaves are important by-products for the recovery of phenolic compounds and extracts with high phenolic content using lactic acid bacteria during fermentation. Lactiplantibacillus plantarum (L. plantarum) strains as glucosidase-positive strains are starter cultures used to control the fermentation process. The main objective of the present work is to determine the most effective strain for the biodegradation of oleuropein to hydroxytyrosol using two L. plantarum strains for the fermentation of olive leaves. Box–Behnken experimental design was applied to determine the optimum ultrasound-assisted extraction (UAE) conditions to obtain hydroxytyrosol-rich extract using the brine of the fermented leaves. L. plantarum ATCC 14917 (hydroxytyrosol; 126.89 ± 1.59 mg/L) strain showed higher oleuropeinolytic activity than L. plantarum ATCC-BAA 793 (85.93 ± 0.70 mg/L) in olive leaf brine. When the UAE method was applied, it was seen that the hydroxytyrosol concentration of samples that were inoculated with L. plantarum ATCC 14917 (362.29 ± 2.31 mg/L) compared to L. plantarum ATCC-BAA 793 (248.79 ± 4.14) increased. The optimum UAE conditions were determined as 30% amplitude-5 min-30% ethanol for ATCC 14917 and 45% amplitude-9 min-10% ethanol for BAA 793 strain. This study showed that the brines of fermented olive leaves with oleuropeinolytic strains can be considered high added value products.

EFFICIENT EXTRACTION OF CURCUMIN FROM TURMERIC WITH PHARMACEUTICAL SOLVENTS AND OPTIMIZATION USING RESPONSE SURFACE METHODOLOGY

The aim of the study was to find out a novel, effective, safe, and eco-friendly method for the extraction of curcumin from turmeric. A pharmaceutically safe solvent isopropyl alcohol was selected based on preliminary screening. Three methods, microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), and maceration were explored, and optimization of each method was performed by RSM with Box-Behnken design. Yield (mg/g) ranged from 1.35-12.53, 1.43-5.59, and 0.23-7.06 (mg/g) in MAE, UAE, and maceration, respectively. For MAE, optimum conditions were 30 mL/g solvent-to-solid ratio (SSR), 240 W microwave power, and 40 s extraction time. The optimum UAE conditions were 40 °C, 10 min and 50 mL/g SSR. The optimum conditions for maceration were 60 °C, 90 min and 10 mL/g SSR. Based on the results, MAE was the most robust technique for extraction of curcumin from turmeric and the protocol may be developed for industrial application.

A novel strategy for producing nano-particles from date seeds and enhancing their phenolic content and antioxidant properties using ultrasound-assisted extraction: A multivariate based optimization study

Date seeds from the date palm fruit are considered as a waste and they are known to contain several bioactive compounds. Producing nanoparticles from the date seeds can enhances their effectiveness and their utilization as novel functional food ingredients. In this study, date seed nanoparticles (DSNPs) synthesized using acid (HCl) hydrolysis method (HCl concentration of 38% and hydrolysis time of 4 days) was found to have particle size between 50 and 150 nm. The obtained DSNPs were characterized by measuring particle size and particle charge (Zetasizer), morphology using scanning electron microscope (SEM), and determination of the functional groups using fourier-transform infrared spectroscopy (FTIR). DSNPs were further treated with green extraction technology [ultrasound-assisted extraction (UAE)] using water-based and methanol-based solvent for optimizing the extraction of the bioactive compounds by implementing response surface methodology (RSM). The UAE of DSNPs were analysed for set of responses including total phenolic content (TPC), total flavonoid content (TFC), 1,1-diphenyl-2-picrlthydrazyl (DPPH) radical scavenging activity, ferric ion reducing antioxidant power (FRAP), and 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activity. Three-factor and four-factor Box-Behnken design (BBD) of three models (Synthesis of DSNPs, UAE with water, and UAE with methanol) was performed. The results showed that in UAE of DSNPs using water-based solvent, the key independent factors effecting the TPC and TFC and antioxidant activities were S:L ratio (40:1 mg/ml) and treatment time (9 min). Whereas the methanol-based UAE of DSNPs was mostly affected by US amplitude/power (90%) and methanol concentration (80%). All models were further optimized using response optimizer in Minitab and the generated predicted values were very comparable to the actual obtained results which confirm the significance and validity of all RSM models used. The phenolic compounds identified from DSNPs consisted mainly of 3,4-Dihydroxy benzoic acid, ferulic acid, and p-coumaric acid. The present study demonstrated a successful method for synthesising DSNPs as well as documented the optimum UAE conditions to maximize the extraction of polyphenolic compounds from DSNPs and enhancing their antioxidant activities to be used in food application.

A Hybrid RSM-ANN-GA Approach on Optimization of Ultrasound-Assisted Extraction Conditions for Bioactive Component-Rich Stevia rebaudiana (Bertoni) Leaves Extract.

Stevia rebaudiana (Bertoni) leaves consist of dietetically important diterpene steviol glycosides (SGs): stevioside (ST) and rebaudioside-A (Reb-A). ST and Reb-A are key sweetening compounds exhibiting a sweetening potential of 100 to 300 times more intense than that of table sucrose. Ultrasound-assisted extraction (UAE) of SGs was optimized by effective process optimization techniques, such as response surface methodology (RSM) and artificial neural network (ANN) modeling coupled with genetic algorithm (GA) as a function of ethanol concentration (X1: 0–100%), sonication time (X2: 10–54 min), and leaf–solvent ratio (X3: 0.148–0.313 g·mL−1). The maximum target responses were obtained at optimum UAE conditions of 75% (X1), 43 min (X2), and 0.28 g·mL−1 (X3). ANN-GA as a potential alternative indicated superiority to RSM. UAE as a green technology proved superior to conventional maceration extraction (CME) with reduced resource consumption. Moreover, UAE resulted in a higher total extract yield (TEY) and SGs including Reb-A and ST yields as compared to those that were obtained by CME with a marked reduction in resource consumption and CO2 emission. The findings of the present study evidenced the significance of UAE as an ecofriendly extraction method for extracting SGs, and UAE scale-up could be employed for effectiveness on an industrial scale. These findings evidenced that the UAE is a high-efficiency extraction method with an improved statistical approach.

Correction to: Optimization of Ultrasonic Extraction of Major Phenolic Components from Flowers of Ghav-Patta (Argyreia Speciosa Linn.) Via Response Surface Model

Ultrasound-assisted extraction (UAE) or ultrasonic extraction technology has been used for the isolation of bioactive compounds from Argyreia speciosa (Linn. f.) Sweet plant (family: Convolvulaceae). Argyreia speciosa is an Indian traditional medicinal plant having strong evidence of various properties widely used in Ayurveda. Dried flowers were used for extraction and the response surface methodology (RSM) was used to optimize the conditions of extraction for the yield of total phenolics and antioxidants from A. speciosa flowers (ASF) in respect of three variables: temperature, power, and time. Damage and structural changes of the bioactive compounds were studied by scanning electron microscopy (SEM) and Fourier-transform infrared (FTIR) spectroscopy techniques. The optimum UAE conditions obtained by RSM for the yield of total phenolic content from ASF were 42.41°C temperature, 43.62 % power, and 26.51 min process time and conditions for the maximum antioxidant activity by DPPH radical scavenging were 41.36°C temperature, 57.02 % power, and 26.63 min. These findings showed that the UAE under optimum conditions increased the percentage yield of bioactive compounds. SEM results showed that there was no relevant damage to the cells, and FTIR spectroscopy verified that there were no changes in chemical structure. It has been concluded that UAE method is an effective technique for enhancing the yields of major phenolic compounds from A. speciosa flowers.

Extraction of Satureja Rechingeri volatile components through ultrasound-assisted and microwave-assisted extractions and comparison of the chemical composition with headspace solid-phase microextraction

ABSTRACT The objective of the present work is comparison between various extraction methods for evaluation of the chemical composition and also extraction yield of theSatureja rechingeri. Efficient parameters of the Ultrasound-assisted extraction (UAE) and the Microwave-assisted extraction (MAE) processes were evaluated and optimized using RSM based on central composite design (CCD). For the approval the effect of various driving forces, chemical components of the essential oil were also determined through the HS-SPME. The highest yields of 4.408% and 4.352% were attained at optimum conditions for UAE and MAE, respectively. Statistical hypothesis testing was showed that there was no significant difference among predicted and experimental data (p > 0.05), proving high capability of models for prediction of the extraction of essential oil from S. rechingeri plant using UAE and MAE processes. Finally, GC/MS analysis technique coupled with aforementioned extraction methods was employed to determine the chemical composition of the extracted essential oils.

Effect of ultrasound-assisted extraction on efficiency, antioxidant activity, and physicochemical properties of sea buckthorn (Hippophae salicipholia) seed oil

Effects of ultrasound-assisted extraction (UAE) conditions viz., treatment time, temperature, solvent to sample ratio, and ultrasound power on antioxidant activity, stability, and extraction efficiency of oil from sea buckthorn (Hippophae salicipholia) seed were studied. The treatment time, temperature, and power showed a significant effect (p < 0.05) on the extraction yield and quality of sea buckthorn seed oil (SBSO). The UAE process could achieve a maximum oil recovery of 6.87 g. hg−1and was significantly higher than that by the solvent extraction technique. The optimum values of UAE conditions attained were at 50 °C for 8.28 min at 552 W ultrasound power with a solvent to sample ratio 10:1 (mL: g). The SBSO samples revealed high carotenoid content (237.04 ± 3.86 mg per 100 g β-carotene equivalent), potent free radical scavenging ability (1.42 ± 0.01 IC50 μg per mL), and oxidative stability (totox value = 8.04 ± 0.02) upon the UAE treatment. GC-MS profiling of the oil sample extracted at optimum UAE conditions exhibited better retention of fatty acids.

Optimization of ultrasound-assisted extraction and the antioxidant activities of Sidaguri (Sida rhombifolia)

Sidaguri (Sida rhombifolia) is widely distributed in tropical and subtropical regions and has been reported to possess many bioactive compounds that are beneficial for human health, including polyphenolics having antioxidant activities. The objective of this study was (1) to optimize ultrasound-assisted extraction (UAE) of Sidaguri and (2) to evaluate antioxidant activities of extracts resulting from the optimized condition using radical scavenging assay of 2,2′-diphenil-1-picrylhydrazyl (DPPH) and 2,2′-azinobis-3-ethylbenzothiazoline-6-sulfonic acid. The optimum UAE conditions obtained were solvent to solid ratio of 26:1, temperature of extraction of 45.45°C, methanol concentration of 42%, power of sonication of 86%, and time of extraction of 5 minutes. Sidaguri obtained from locations of Kretek and Ngemplak had the highest radical scavenging activity accounting for 83.69% ± 0.30% and 82.95% ± 0.49%, respectively.

Optimized ultrasound-assisted extraction of total polyphenols from Empetrum nigrum and its bioactivities

Optimization of ultrasound-assisted extraction (UAE) of total polyphenols (TPP) from Empetrum nigrum aerial parts was carried out by response surface methodology (RSM). The optimum UAE conditions of extraction time, extraction temperature, ethanol concentration, and solvent-to-material ratio were 21.38 min, 42.32 °C, 61.93% and 53.29:1 mL/g, respectively. Under the optimum conditions, the extraction yield of TPP was 32.17 ± 0.46 mg/g, which was 1.29–1.44 folds to those by the conventional extraction methods. In addition, the bioactivities of the extracts were investigated. Antioxidant activity test by the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) assay revealed that the TPP extracts had a high potential for free radical scavenging activity. The TPP extracts showed remarkable antibacterial activity against both Gram-positive and Gram-negative strains, especially against Gram-positive strains. The evaluation of antitumor activity by the MTT assay and flow cytometric analysis indicated that the TPP extracts significantly inhibited B 16F 10 melanoma cell proliferation and effectively induced apoptosis of melanoma cells. These results demonstrate that E. nigrum aerial parts are rich in TPP and show great application potential in the pharmaceutical industry.

괭생이모자반으로부터 미백과 주름개선 생리활성물질 생산을 위한 초음파 추출공정 개발

Statistically-based optimization using response surface methodology was performed to derive optimal extraction conditions for the extraction of bioactive compounds with antioxidant activity, skin whitening, and anti-wrinkle effects from Sargassum horneri, marine waste, using the ultrasound-assisted extraction (UAE). The main UAE process variables, extraction time (5.3~18.7 min, X₁), extraction temperature (22.4~79.6°C, X₂), and ethanol concentration (0~99.5% v/v, X₃), were selected through preliminary experiments and optimized using central composite design at five levels. Total phenolic content (TPC), total flavonoid content (TPC), DPPH radical scavenging activity (RSA), tyrosinase activity inhibition (TAI), and collagenase activity inhibition (CAI) were analyzed and second-order polynomial models were generated for predicting the responses. The optimum UAE conditions for enhancing antioxidants, skin whitening, and anti-wrinkle effects were extraction time of 11.7 min, extraction temperature of 54.8°C, and ethanol concentration of 73.0%, under which RSA, TAI, and CAI were 29.1%, 78.5%, and 83.6%, respectively. In this study, we proposed an extraction process for the production of cosmetic materials that have a combination of antioxidant, whitening, and wrinkle effects from S.horneri, which are marine waste.

Optimization of ultrasound-assisted extraction of bioactive properties from date palm (Phoenix dactylifera L.) spikelets using response surface methodology

Response surface methodology (RSM) was applied to optimize the experimental conditions for ultrasound-assisted extraction (UAE) to maximize the recovery of total phenolic content (TFC) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity from date palm spikelets (DPS). A three-factor [temperature (25 °C, 42.5 °C, and 60 °C), duration (20, 30, and 40 min), and ethanol concentration (25%, 37.5%, and 50%)] and three-level (−1, 0, and +1) Box–Behnken design (BBD) was applied. Sonication temperature and ethanol concentration were the major factors influencing the recovery of total phenolic content (TPC) and DPPH radical scavenging activity from DPS. The experimental values [TPC, 130.2 mg gallic acid equivalents (mg GAE/g), and DPPH radical scavenging activity, 87.5%] well matched with the predicted values (TPC, 124.5 mg GAE/g, and DPPH radical scavenging activity, 87.2%) at the optimum UAE conditions (temperature 40.8 °C, duration 21.6 min, and ethanol concentration 50.0%), which confirmed the validity of the applied RSM model. The major phenolic compounds in DPS determined at optimized UAE conditions were rutin and (+)-catechin. This study identified the ideal UAE settings for the maximum recovery of bioactive compounds from DPS for possible utilization of date byproducts in food applications.

The optimization of ultrasonic method for the extraction of Pumpkin seed (Cucurbita maxima)

The purpose of the present study was to determine the optimal ultrasound-assisted extraction (UAE) conditions (sample-to-solvent ratio, ultrasonic power, and time) for the extraction of pumpkin seed oil. Pumpkin seed oil was analyzed for yield, 2.2’-Diphenyl-1-picrylhydrazyl (DPPH) scavenging activity, and total phenolic content. Soxhlet extraction methods were assessed for comparison. The Box Behnken design (BBD) was applied to optimize UAE conditions. The optimum UAE conditions were obtained using sample-to-solvent ratio of 1:10 mL g-1, ultrasonic power of 150 Watt in 15 min extraction time. Compared with Soxhlet extraction methods, UAE exhibited lower oil yield and total phenolic content but had higher DPPH scavenging activity. The advantage of ultrasonic-assisted extraction was clearly reduction of extraction duration.

Modeling and optimization of ultrasound-assisted green extraction and rapid HPTLC analysis of stevioside from Stevia Rebaudiana

Stevioside is the major constituent of the Stevia Rebaudiana plant. The aim of this study is to appraise optimum procedure conditions for extraction of stevioside from Stevia Rebaudiana by Peleg’s mathematical methodology. Stevioside from dried leaves of Stevia Rebaudiana was extracted by means of probe type sonication system using glycerol as a green and generally recognized as safe (GRAS) solvent. High Performance Thin Layer Chromatography (HPTLC) was used as a very efficient, rapid and precise method for stevioside detection and analysis. Results demonstrated that the optimum conditions for ultrasound-assisted extraction (UAE) of stevioside from Stevia Rebaudiana are glycerol as solvent, temperature of 70 °C, plant to solvent proportion of 1:30, plant powder particle size of 0.075 mm, 200 W ultrasound irradiation power and 20 kHz ultrasound irradiation frequency. The comparing experimental results for Ceq of extracted stevioside with calculated values from Peleg’s mathematical model showed good and acceptable agreement. As a consequence, it was concluded that the ultrasound-assisted extraction is an efficient, fast, and economic method for extraction of stevioside from Stevia Rebaudiana in comparing with Soxhlet and maceration methods. Moreover, selected mathematical model displays the system with an acceptable accuracy which can predict the optimal conditions for extraction of stevioside those are close enough to experimental results.Practical Applications This investigation presented a mathematic model and experimental approach for the optimization of stevioside content of Stevia Rebaudiana using the ultrasound-assisted extraction and HPTLC analysis. Compared with the classic methods for optimizing of stevioside using the mathematic approaches or chemical experiments, the Peleg’s method is more precise and convenient. Moreover using ultrasound and HPTLC as extraction and analysis method, respectively, provides safer, rapid, and simple way for their stevioside extraction. Therefore, the method demonstrated in the present investigation could be used to extract the stevioside of Stevia Rebaudiana in food and beverage industries.

Optimization of Ultrasound-Assisted Extraction of Antioxidants from Apium graveolens L. Seeds using Response Surface Methodology

In this study, optimum conditions for ultrasound-assisted extraction (UAE) of antioxidants from Apium graveolens L. seeds were investigated by Response Surface Methodology (RSM). A Box-Behnken Design (BBD) was used to evaluate the effect of sonication time (5, 10, 15 min), ultrasound power (60, 120, 180 W) and the ratio of extraction solvent in terms of methanol (0, 50, 100%) on antioxidant capacity. The optimal UAE conditions for the parameters investigated were 11 min of sonication time, ultrasound power of 131 W and 100% methanol as an extraction solvent. Under these conditions, UAE of antioxidants from the seeds achieved a maximum of 95.08% in respect to 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity. Additionally, the high value of the adjusted coefficient of determination ( R 2 adj = 0.9192) and the non-significant difference between experimental and predicted values confirmed the validity of the quadratic polynomial model. Hence, UAE is a suitable, fast, economical and practical technique for the extraction of antioxidants from Apium graveolens L. seeds.

Optimization of ultrasound-assisted extraction of glycyrrhizic acid from licorice using response surface methodology

BackgroundThe present study optimized ultrasound-assisted extraction conditions to maximize extraction yields of glycyrrhizic acid from licorice. MethodsThe optimal extraction temperature (X1), extraction time (X2), and methanol concentration (X3) were identified using response surface methodology (RSM). A central composite design (CCD) was used for experimental design and analysis of the results to obtain the optimal processing parameters. ResultsStatistical analyses revealed that three variables and the quadratic of X1, X2, and X3 had significant effects on the yields and were followed by significant interaction effects between the variables of X2 and X3 (p<0.01). A 3D response surface plot and contour plots derived from the mathematical models were applied to determine the optimal conditions. The optimum ultrasound-assisted extraction conditions were as follows: extraction temperature, 69°C; extraction time, 34min; and methanol concentration, 57%. Under these conditions, the experimental yield of glycyrrhizic acid was 3.414%, which agreed closely with the predicted value (3.406%). ConclusionThe experimental values agreed with those predicted by RSM models, thus indicating the suitability of the model employed and the success of RSM in optimizing the extraction conditions.

Optimization of ultrasound-assisted extraction of oil from olive pomace using response surface technology: Oil recovery, unsaponifiable matter, total phenol content and antioxidant activity

The optimum conditions for ultrasound-assisted extraction of olive pomace oil were determined by response surface methodology (RSM). The effect of temperature, solid/liquid ratio and particle size was investigated on oil yield, its unsaponifiable matter (USM%), total phenol content (TPC) and antioxidant activity (DPPH). The optimal condition for the oil yield was: temperature, 60 °C, solid/liquid ratio, 1/12 g/mL and particle size, 0.5 mm. At this condition, the oil recovery was 11.03% which well matches with the predicted value. The optimal point for the USM% was achieved when the UAE is carried out at 55 °C using solid/liquid ratio 1/12 g/mL and particle size 0.5 mm. The optimal conditions for TPC of olive pomace oil obtained and its antioxidant activity were as follows: temperature, 50 °C, solid/liquid ratio, 1/8 g/mL and particle size, 0.9 mm and temperature, 55 °C, solid/liquid ratio, 1/8 g/mL and particle size, 0.9 mm, respectively. Close agreement between experimental and predicted values for USM%, TPC and DPPH was found.

Optimization of ultrasound-assisted antioxidant compounds extraction from germinated chickpea using response surface methodology

The optimum ultrasound assisted extraction (UAE) parameters (power, time and solid/liquid ratio) for the extraction of antioxidant compounds from germinated chickpea were determined by response surface methodology (RSM). Box-Behnken design (BBD) was employed to investigate the effects of three independent variables, total phenolic content (TPC), DPPH radical scavenging activity and trolox equivalent antioxidant capacity (TEAC). The prediction of the response was carried out by a second-order polynomial model and regression analysis revealed that more than 88% of the variation can be explained by the models. The optimum conditions for UAE of germinated chickpea samples were; %40 solid/liquid ratio, 36.16% amplitude power and 20.17 min and the experimental values of TPC, DPPH radical scavenging activity and TEAC were, 14.77 mg GAE/mL extract, 43.31% and 73.59%, respectively. Results confirmed that germination results in higher antioxidant values and RSM optimization of UAE is more efficient than conventional extraction.