Microwave-assisted Extraction Method Research Articles

Total Iodine Quantification and In Vitro Bioavailability Study in Abalone (Haliotis discus hannai) Using Inductively Coupled Plasma Mass Spectrometry.

The aim of this study is to determine the total iodine content in Korean abalone (Haliotis discus hannai) and to investigate the bioavailability of iodine using an in vitro method. This research paper focuses on total iodine quantification in abalone (Haliotis discus hannai) and its components (viscera and muscle) using inductively coupled plasma mass spectrometry (ICP-MS). Additionally, an in vitro bioavailability study explored iodine absorption potential. Abalone pretreatment involved both the European standard method (ES) and microwave-assisted extraction method (MAE). The limits of detection (LOD) were 0.11 ng/g for both ES and MAE, with a limit of quantification (LOQ) of 5.4 ng/g for MAE. Accuracy, assessed using a reference material (fish muscle, ERM-BB422), showed values of 1.5 ± 0.010 mg/kg for ES and 1.6 ± 0.066 mg/kg for MAE, within an acceptable range of 1.4 ± 0.42 mg/kg. Precision, evaluated using the Horwitz ratio (HorRat) with a reference material, was determined to be 0.45 for ES and 0.27 for MAE. Therefore, total iodine contents were estimated as 74 ± 2.2 µg/g for abalone viscera and 17 ± 0.77 µg/g for abalone muscle with ES, and 76 ± 1.0 µg/g for abalone viscera and 17 ± 0.51 µg/g for abalone muscle with MAE. Recovery tests demonstrated an acceptable range of 90-110%. In the in vitro bioavailability assessment, digestion efficiency yielded ranges of 42-50.2% for viscera and 67-115% for muscle. Absorption efficiency variations were determined as 37-43% for viscera and 48-75% for muscle.

Optimization of Sulfated Polysaccharides Extraction from Gracilaria fisheri Obtained Through Microwave-Assisted Extraction

Gracilaria fisheri is a red seaweed that possesses several biological activities. The major important compounds comprising this seaweed are sulfated polysaccharides. However, limited data exists on the optimal extraction conditions for this seaweed using eco-friendly techniques like microwave-assisted extraction (MAE). This work aimed to optimize the MAE conditions for extracting sulfated polysaccharides from G. fisheri. Three factors influencing MAE were investigated: microwave time, solvent-to-solid ratio, and microwave power. These factors were initially screened by varying one factor at a time to identify levels leading to high extraction yields. These levels were then included in a Box-Behnken design. Microwave time was varied from 20 to 40 s, solvent-to-solid ratio from 8:1 to 10:1 mL/g, and microwave power from 300 to 600 W. Two responses were monitored: extraction yield and sulfate content. The optimal condition for both high extraction yield and sulfate content was found to be 30 s of microwave time, a solvent-to-solid ratio of 9.5:1 mL/g, and 450 W of microwave power. This condition yielded 20.32-20.93% extraction yield and 48.28-49.95% sulfate content. The computer program's predictions were accurate and reliable, with a very low percentage error of less than 3%. Therefore, the Box-Behnken design proved to be an effective tool for optimizing the extraction of sulfated polysaccharides from G. fisheri using the MAE method.

A Mini-review on the Chemical Composition, Extraction and Isolation Techniques, and Pharmacological Activity of Rosmarinus officinalis L.

Abstract: Rosmarinus officinalis L. belongs to the genus Rosemary in the family Labiatae, which is a perennial evergreen subshrub. It is currently cultivated in certain areas of Yunnan, Guangxi, and Guizhou. At present, in food, cosmetics, healthcare products, and other domains, R. officinalis has a wide range of applications; it has received widespread attention, and is also a hot topic of research today. Using modern spectroscopic techniques, it has been found that the main chemical components of rosemary can be divided into two major groups, including volatile components (essential oils) and non-volatile components (diterpenes, triterpenes, flavonoids, phenolic acids, sterols, etc.). Among them, carnosic acid, carnosol, rosemary phenol, and 1,8-cineole are the main components acting as antioxidants and they are highly regarded. The main methods for extracting the active ingredients of R. officinalis include water distillation, ultrasonic-assisted microwave method, supercritical CO2 extraction method, enzyme-assisted extraction method, and microwaveassisted extraction method. Modern research has shown that rosemary has anti-inflammatory, antioxidant, antibacterial, antiviral, antitumor, hepatoprotective, hypolipidemic, immunomodulatory, antiseptic, and antithrombotic effects, and is widely used in medical applications.

Maximizing Curcuminoid Extraction from Curcuma aromatica Salisb. Rhizomes via Environmentally Friendly Microwave-Assisted Extraction Technique Using Full Factorial Design.

Curcuma aromatica Salisb. contains a high content of curcuminoids, which can be utilized for cosmetic purposes. The objective of this study was to optimize the extraction conditions of C. aromatica rhizomes in castor oil to maximize curcuminoid content using a simple and environmentally friendly microwave-assisted extraction method. A 32 full factorial design was employed, with two factors-microwave power and time-varying between 600-800 W and 30-90 s, respectively. Five responses were monitored, including extraction yield, bisdemethoxycurcumin, demethoxycurcumin, curcumin, and total curcuminoid contents. The results demonstrated that increasing microwave power and time led to an increase in all five responses. The optimal condition, which simultaneously maximized extraction yield and total curcuminoid content, was achieved at a microwave power of 800 W for 90 s. This condition resulted in an extraction yield of 71.020%, bisdemethoxycurcumin content of 0.036%, demethoxycurcumin content of 0.210%, curcumin content of 0.080%, and total curcuminoid content of 0.326%. The computer program accurately predicted the results with a percentage error of less than 2%. Stability data revealed that the total curcuminoid content remained stable with a percentage remaining above 90% when stored at 4°C, 30°C ± 75%RH, and 40°C ± 75%RH for three months. In summary, this study successfully applied a full factorial design to maximize curcuminoid extraction from C. aromatica rhizomes using an environmentally friendly microwave-assisted extraction method for cosmetic purposes.

Impacts of microwave-assisted extraction parameters on total phenolic compounds yield from Algerian Moringa oleifera leaves, using response surface methodology

The study aimed to optimise the microwave-assisted extraction (MAE) of total phenolic compounds (TPC) from Moringa oleifera Lam. leaves using response surface methodology (RSM) and Box-Behnken designs (BBD). Factors such as ethanol concentration, microwave power, irradiation time, and solvent to solid ratio were assessed in single-factor tests. Under optimal extraction conditions (48.86% ethanol, 626.53 W microwave power, 99.48 s irradiation, 29.67 mL/g solvent to solid ratio and 21.12 W/mL power density), TPC was 58.45 ± 0.68 mg GAE/g DW, close to the predicted 59.78 ± 1.47 mg GAE/g DW. The MAE method outperformed maceration extraction (8.41 ± 0.25 mg GAE/g DW) and decoction extraction (38.74 ± 0.81 mg GAE/g DW) in terms of extraction time, solvent use, and efficiency. The optimised extract exhibited significant antioxidant activity with IC50 values of 0.294 ± 0.004 mg/mL (DPPH) and 0.425 ± 0.005 mg/mL (ABTS), confirming the efficacy of MAE in preparing antioxidant-rich plant extracts.

Heat, ultrasound, and microwave assisted extraction methods for recovering bioactive components from hawthorn fruit (Crataegus monogyna Jacq.)

AbstractIn this work, an assessment of effective solvents and extraction methods was carried out to recover the bioactive compounds from hawthorn fruit (Crataegus monogyna Jacq.). Extractions assisted by heat, microwave, and ultrasound were carried out using various organic solvents (methanol, ethanol, and isopropanol). pH differential, Folin–Ciocalteu's, and aluminum chloride methods were used to determine total monomeric anthocyanin (TMA), total phenolic compound (TPC), and total flavonoid content (TFC), consecutively. Ferric Reducing Antioxidant Power (FRAP), 2,2-Diphenyl-1-picrylhydrazyl Hydrate (DPPH), and 2,2′- azino- bis (3-ethylbenzothiazoline-6- sulfonic acid) (ABTS) assays were used to measure the antioxidant activity (AA) of the extracts. The outputs revealed that extraction methods and solvents significantly affect anthocyanin concentration, TPC, TFC, AA, and color values of hawthorn fruit extracts. Due to the highest recovered TMA (0.152 ± 0.002 mg ECy3Gl/g of dry weight), TPC (49.14 ± 0.38 mg gallic acid equivalents/g of dry weight), and TFC (18.38 ± 0.19 mg quercetin equivalents/g of dry weight) contents, the ultrasonic-assisted extraction is superior to heat and microwave-assisted extractions. Accordingly, it was also observed that the methanol solvent is more profound than ethanol and isopropanol. Further, the bioactive compounds' content and the extracts' antioxidant activity are shown to be highly correlated. Thus, hawthorn extracts are considered to have antioxidant properties because of their concentrated bioactive compounds.

Chemical Composition of Hydrodistillation and Solvent Free Microwave Extraction of Essential Oils from <i>Plectranthus amboinicus </i>and <i>Melaleuca cajupati</i> Leaves and their Repellent Activity

Extraction of the native plants Plectranthus amboinicus and Melaleuca cajupati leaves have been carried out using traditional hydrodistillation (steam distillation) and solvent free microwave-assisted extraction methods at different temperatures and microwave irradiation powers. The chemical compositions of the essential oils extracted were identified using gas chromatography analysis. The ideal extraction time for Pletranthus amboinicus and Melaleuca cajupati were 120 min with microwave power 200 W and 400 W, respectively with the calculated extraction yield were 0.034 % and 0.276 %, respectively. In this paper, the results of the selected microwave powers, first oil drops, and extraction time are presented as well as the findings of the chemical compositions present in both plants are also discussed.

Proximate Composition, Phytochemical Analysis and Toxicity Assessment of Extracts of Caulerpa lentillifera using Autoclave- and Microwave-Assisted Extractions

Caulerpa lentilliferais a marine alga widely cultured and consumed in Asia and Oceania. Emerging green techniques are currently popular for phytochemical extraction. Therefore, this study aimed to investigate the proximate compositions, phytochemicals, and antioxidant properties of the C. lentilliferaextracts using autoclave-assisted and microwave-assisted extraction methods (A-CLE and M-CLE, respectively). The toxicity of extracts was tested against human normal colon cells and freshwater crustacean Daphnia magna. We found that crude lipid, ash and moisture contents in A-CLE were lower than those in M-CLE, while crude protein and crude carbohydrate were higher in A-CLE. Total flavonoid content in A-CLE (1.474 ± 0.046 mg QE g-1 extract) was higher than that in M-CLE (1.179 ± 0.054 mg QE g-1 extract). There was no difference in total phenolic contents, triterpenoid contents and antioxidant activities between the extracts. The IC50 of A-CLE (12,260 ± 197 µg mL-1) was higher than that of M-CLE (10,950 ± 169 µg mL-1). In the acute toxicity test, the LC50 of A-CLE against D. magna (7.50 ± 0.28 g L-1) was lower than LC50 of M-CLE (8.76 ± 0.26 g L-1). This study suggest that autoclave-assisted and microwave-assisted extractions are effective green methods of extracting C. lentillifera. This study will be useful for further studies of C. lentillifera extracts to improve human and animal health.

Microwave-assisted extraction of pectin from onion and garlic waste under organic, inorganic and dual acid mixtures

AbstractThis study aims to investigate pectin extraction from garlic (GW) and onion waste (OW) by microwave-assisted (MAE) and sequential microwave assisted-hot acid extraction (MAHE) methods. All extractions were performed under three different media including organic acids [citric (CA) and acetic (AA)], inorganic acids [sulfuric (H2SO4) and hydrochloric (HCl)] and their mixtures. GW provided more pectin yields compared with OW. While the highest pectin yields from GW and OW by MAE in H2SO4 were respectively 24.62 ± 0.65 and 24.93 ± 0.59%, these yields under MAHE were 27.99 ± 0.36 and 28.43 ± 0.42%, respectively. Higher pectin yields and galacturonic acid (Gal-A) contents were mostly achieved in inorganic acids. However, degree of esterification (DE), methoxyl content (MeO) and equivalent weight (EW) values were higher for the pectins extracted under organic acids. Extraction of pectin from GW and OW was also accomplished in dual acidic media by MAE. Addition of inorganic acids to the organic acid solutions resulted in increasing pectin yields. The highest pectin yields from GW and OW under dual acid solutions were respectively 23.36 ± 0.66 and 21.88 ± 0.52%, and achieved in 1/3 HCl-H2SO4 and 1/3 CA-H2SO4 mixtures by MAE. While increasing inorganic acid contents in dual acid solutions resulted in enhanced Gal-A contents, increasing organic acid volume also generated higher DE and MeO values of the pectins. Obtained successful outcomes indicate that MAHE method could be used as an efficient extraction technique for the higher pectin yields, and utilization of organic-inorganic dual acid mixtures during MAE provides enhanced yields and controlled physicochemical properties of pectin. Graphical abstract

Microwave and ultrasound assisted extraction techniques with citric acid of pectin from Pomelo (Citrus maxima) peel

This current research attempted to obtain pectin from Pomelo (Citrus maxima) peels using conventional heating, microwave-assisted extraction (MAE), and ultrasound-assisted extraction (UAE) techniques with organic citric acid. In order to characterize pectin extracted using conventional heating, MAE, and UAE, yield, pH, solubility, ash content, equivalent weight, anhydrouronic acid content, degree of esterification methoxyl content were taken into consideration. On physicochemical properties, the extraction techniques had a significant effect. The findings demonstrated that the MAE method produced the highest amount of pectin (26.63 ± 0.21 %). On the basis of the Degree of Esterification (DE) value, pectins were all classified as high-methoxypectins (HMP). According to anhydrouronic acid (AUA) content, the extracted pectins were extremely pure. Fourier transform infrared (FT-IR) spectroscopy was used to structurally characterize pectin that was extracted using three different methods, and the results revealed that pectin has functional groups between 1740 and 800 cm-1 spectrally.

Cellulose nanocrystals from marine algae Cladophora glomerata by using microwave-assisted extraction

Algae of the order Cladophorales are the source of a unique nanocellulose with high crystallinity and a large aspect ratio, enabling broad surface modification. Cellulose nanocrystals (CNCs) are obtained via acid hydrolysis of nanocellulose, which is highly crystalline. However, the production of CNCs from Cladophorales algae is limited and still uses a conventional heating method. Thus, this study aimed to develop a microwave-assisted extraction (MAE) method for fast and efficient extraction of CNCs from Cladophora glomerata algae. Additionally, we replaced the use of hypochlorite with H2O2, which is more environmentally friendly, and compared the CNCs obtained from the conventional methods with our new method. The functional structure of CNCs was confirmed by Fourier-transform infrared spectroscopy. Single-step H2O2 bleaching with MAE yielded the smallest-sized CNCs. Our developed method resulted in the production of CNCs with a high crystallinity index, high thermal stability, and high purity of native cellulose. Additionally, none of the CNCs were toxic to primary normal human dermal fibroblasts. The properties of the isolated CNCs may make them useful materials in pharmaceutical and cosmetic formulations.

Effects of different extraction methods on the physico-chemical characteristics and biological activities of polysaccharides from Clitocybe squamulosa

This study comparatively evaluated the effects of the commonly used six extraction methods (acidic, alkaline, enzymatic, ultrasonic, high-pressure, and microwave) on the physico-chemical properties, processing characteristics, and biological activities of polysaccharides from Clitocybe squamulosa (CSFPs). The results show that polysaccharides extracted using an enzyme-assisted extraction method has a relatively high extraction yield (4.46 ± 1.62 %) and carbohydrate content (70.79 ± 6.25 %) compared with others. Furthermore, CSFPs were all composed of glucose, galactose, mannose, xylose, and glucosamine hydrochloride. Only ultrasonic-assisted extraction of polysaccharides (CSFP-U) has a triple helix chain conformation. Scanning electron microscopy (SEM) revealed significant differences in the microstructure of polysaccharides prepared using different methods. Besides that, the polysaccharides prepared by alkali extraction (CSFP-B) and high-pressure assisted extraction (CSFP-H) have good water (2.86 ± 0.29 g/g and 3.15 ± 0.29 g/g) and oil (8.13 ± 0.32 g/g and 7.97 ± 0.04 g/g) holding properties. The rheological behavior demonstrated that CSFPs solutions were typical non-Newtonian fluid. Apart from this, the antioxidant capacity (clearing DPPH (IC50 = 0.29) and ABTS free radicals (IC50 = 0.19), total reduction ability (IC50 = 3.02)) of polysaccharides prepared by the microwave-assisted extraction (CSFP-M) method was significantly higher than that of other extraction methods. By contrast, the polysaccharide prepared by acid extraction (CSFP-A) has the optimum binding capacity (bile acid salt (71.30 ± 6.78 %) and cholesterol (57.07 ± 3.26 mg/g)). The antibacterial activity of CSFPs was positively correlated with their concentration. Thus, the research results can provide a theoretical basis for the development and utilization of polysaccharides from C. squamulosa.

Innovative ultrasound sonication pretreatment sparger-based microwave assisted extraction method for enhanced essential oil extraction from lemon grass

This study introduces an innovative approach, Ultrasonic Sonication Pretreatment Sparger-based Microwave Assisted Extraction (U Sp-MAE), designed to enhance lemongrass essential oil extraction. Addressing the challenge of maximizing yield and quality, our work systematically optimized key extraction parameters. Results demonstrated a significant improvement over conventional methods, with the highest yield of 1.89% achieved under specific conditions: a Sparger Flow rate of 4 L/min, Ultrasound Power of 700 W, Sonication Time of 5 min, and Liquid-to-Solid Ratio of 5 mL/g. This method not only advances essential oil extraction but holds promise for broader applications in society, showcasing its potential impact on sustainable and efficient resource utilization.

Microwave-assisted extraction of Lawsonia inermis L. leaves: Method validation, optimization, and tyrosinase-stimulating activity

Vitiligo is a long-term skin condition characterized by the development of pale white patches due to a lack of melanin. Lawsonia inermis L. leaves, which contain lawsone, have been explored as a potential alternative treatment for vitiligo. This study aimed to optimize the microwave-assisted extraction of L. inermis leaves and evaluate its ability to stimulate tyrosinase activity, which is relevant to vitiligo treatment. The Box-Behnken design was employed, with three factors being varied: microwave power, time, and cycle. Two responses were monitored: extraction yield and lawsone content. To determine the lawsone content, validated high-performance liquid chromatography was utilized, which demonstrated good linearity, specificity, precision, and accuracy. The optimal conditions that provided the highest extraction yield and lawsone content were then used to evaluate the extract’s ability to stimulate tyrosinase activity. The results revealed that a microwave power of 300 W and a microwave time of 20 s for one cycle yielded an extraction yield of 12.99% ± 0.10% and a lawsone content of 94.85 ± 3.12 mg/g extract. The accuracy of the prediction, with a percent error of less than 10%, confirmed the reliability of the computer program used for data prediction. Furthermore, the extract exhibited significant stimulation of tyrosinase activity, indicating its potential usefulness in vitiligo treatment. The optimal microwave-assisted extraction method identified in this study holds promise for maximizing extraction yield and lawsone content in L. inermis leaves extract. This extract could serve as a basis for developing topical products for the treatment of vitiligo.

Antibacterial film-forming spray containing Caesalpinia sappan L. extract obtained through eco-friendly microwave-assisted extraction

The heartwood of Caesalpinia sappan L. contains brazilin, which exhibits excellent antibacterial activity. Its extract shows potential for incorporation into topical antibacterial products. This study aimed to optimize the conditions of an eco-friendly microwave-assisted extraction method to maximize brazilin content and antibacterial activity. It also optimized the film-forming antibacterial spray containing C. sappan heartwood extract using a Box–Behnken design. Ethanol concentration, microwave power, and microwave time were varied for microwave-assisted extraction. The optimized conditions of 28 % ethanol, 800 W microwave power, and 70-s microwave time maximized the extraction yield, brazilin content, and clear zones against Staphylococcus aureus and Staphylococcus epidermidis. The optimized extract was then incorporated into a film-forming spray. The film-forming spray formula's hydroxypropyl methylcellulose, glycerin, and ethanol contents were varied. Based on the design space, the optimized formulation comprised 0.6 % hydroxypropyl methylcellulose, 1.25 % glycerin, and 28 % ethanol. Approximately 97 % of the brazilin was released from the formulation during an 8-h release experiment. Moreover, approximately 25 % of the brazilin accumulated in the synthetic human skin-like membrane during an 8-h permeation experiment. In summary, this study successfully prepared, characterized, optimized, and verified a film-forming spray containing the optimized C. sappan heartwood extract obtained through microwave-assisted extraction.

An extraction technique to reach the effective radical scavenging constituents from the leaves of Indonesian malva nut tree (Scaphium macropodum): A comparative study of maceration, heat-assisted, ultrasound-assisted, and microwave-assisted extraction

Scaphium macropodum (Miq.) Beumée ex K. Heyna is an Indonesian commodity that has been widely used as an herbal medicine. This study examined the total phenolic content (TPC), flavonoid content (TFC), and antioxidant properties of Scaphium macropodum leaves. The leaves were extracted by several methods, including maceration, heat-assisted (HAE), ultrasound-assisted (UAE), and microwave-assisted extraction (MAE) using water, methanol, and ethanol solvents. The TPC value varied within the range of 14.03–97.34 mg GAE/g extract, while the TFC was not detected in water extract and ranged from 61.99 to 88.15 mg QE/g extract for alcohol solvents. The tested extracts showed great antioxidant properties by DPPH (1,1-Diphenyl-2-picrylhydrazyl) and ABTS [2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical scavenging with the inhibition percentage ranging from 3.21 to 48.62% at the concentration 25 μg/mL for DPPH and 19.48–97.44% at the concentration 20 μg/mL for ABTS assays. The statistical analysis and PCA (Principal component analysis) were conducted to obtain the proper extraction technique. The MAE method using ethanol solvent was the most suitable technique for extracting the valuable compounds of Scaphium macropodum leaves. These findings suggest the potential uses of Scaphium macropodum leaves as an alternative natural medicine with useful bioactive constituents providing good antioxidant activity.

Characterization of Andrographis Paniculata Extract Obtained by Microwave-Assisted Extraction (MAE) Method with Radiation Time

The purpose of this research was to extract Andrographis paniculata using the Microwave Assisted Extraction (MAE) method at 4 radiation (4 minutes, 6 minutes, 8 minutes, and 10 minutes) and characterize the extract on phenolic content, flavonoid content, andrographolide content, antioxidant activity, and functional group using Fourier Transform Infrared Spectroscopy (FTIR). Radiation times of the MAE method had a significant effect on phenolic content, flavonoid content, andrographolide content, and antioxidant activity of Andrographis paniculata. Radiation time for 10 minutes of MAE gave higher phenolic, flavonoid, andrographolide, and antioxidant activity of Andrographis paniculata. The IR spectra of the Andrographis paniculate extract increased as the radiation time increased. The optimum radiation time was at 8 minutes with the result of phenolic content at 57.2 mg GAE /g, flavonoid content at 113.07 ppm, andrographolide at 763.47 µg/ml, antioxidant activity at 71.66% and the IR spectra at 1031.92 cm-1, 2945.3 cm-1, 3346.5 cm-1.

Comparison of extraction methods on anthocyanin pigment attributes from mangosteen (Garcinia mangostana L.) fruit rind as potential food colourant

The mangosteen fruit is mostly consumed for its pulp, and the rind, which accounts for more than 60 % of the total fruit weight, is discarded making it poor economic worth. The dark purple rind of mangosteen fruit is a rich source of anthocyanin pigment that can be used for food application if extracted using eco-friendly solvents. The aim of the study was to come up with an efficient, cheap and environmentally friendly method of anthocyanin pigment extraction from mangosteen fruit rind. Acidified solvent has shown to have higher recovery percentage of the pigment concentrate having higher TMAC (17,652.54 mg/L), colour density (1596.30 AU), polymeric colour (997.80 AU). Significantly highest recovery percentage (55.03), antioxidant activity measured by DPPH (2.29 l/ml), FRAP (2.83 l/ml), and ABTS (2.02 l/ml), total phenolics (32.25 mgGAE/100 g), total flavonoid content (40.02 mgQE/100 g), as well as the instrumental colour values indicating bright reddish-purple, were observed in microwave assisted extraction method with acidified solvent. By LC-MS/MS analysis, it was also evident that the rind contains a number of beneficial and health-promoting compounds, such as anthocyanins, xanthones, phenolics, flavonoids, coumarins, phoroglucinol derivatives, lignans, retinoids.

The Extraction of Oxalate Acid from Porang Flour (Amorphophallus oncophyllus) using Microwave-Assisted Solvent Extraction

Porang (Amorphophallus oncophyllus) is one of the local annual plants that contain high levels of oxalate. Oxalates are undesirable compounds in porang flour, and their levels must be removed or reduced to obtain high quality porang flour as a food ingredient. In this research, the extraction of oxalate acid was conducted using microwave-assisted solvent extraction and mechanical separation methods. This study aims to analysis the parameters that influence the extraction of oxalate acid using microwave-assisted solvent extraction such as the effect of microwave power, extraction time, feed-to-solvent ratio (F/S) and material size. The mechanical separation process will be studied the effect of material size for extraction of oxalate acid. The optimum yield obtained for oxalate acid extraction with microwave-assisted solvent extraction was microwave power of 600 W, extraction time of 30 min, feed-to-solvent ratio of 0.05 g/mL and porang size of 100 mesh obtained by oxalate acid yield of 24.78%. Porang size of 100 mesh was the optimum yield obtained for extraction of oxalate acid using mechanical separation method. The result of physical properties test using SEM-EDX and FTIR shows that extraction of oxalate acid from porang using microwave extraction method could produce oxalic acid which has good quality. In addition, extraction using microwave offers an environment-friendly extraction method, which can accelerate and increase the oxalate acid extraction yield.

Effect of microwave assisted extraction on total phenolic, flavonoids, and antioxidant from Stenochlaena palustris leaves

Degenerative disease is a disease caused by too many free radicals in the body. To neutralize, reduce, and inhibit the formation of new free radical compounds in the body, antioxidant compounds are needed. One source of antioxidants can come from plants that contain phenolic compounds. S. palestris plant is one of the plants from Bangka Belitung which contains phenolic compounds. The purpose of this study was to determine the effectiveness of the microwave assisted extraction method for the total phenolic and flavonoid content and antioxidants in the chloroform, acetone, and methanol extracts of S. palustris leaves with MAE times of 5, 10, 15, and 30 minutes (60° C, 1200 Watts). Based on the results of the analysis of the average yield values, total phenolics, total flavonoids, and antioxidant activity of the leaves of S. palustris using the MAE method had higher results compared to maceration. Based on the time difference used, the 5 minute MAE time has a higher value than the 10, 15, and 30 minute time. In terms of the extraction time used and the results obtained, the MAE method is more efficient and effective than the maceration method.