Comparison of Ultrasound-Assisted Extraction of Pumpkin Seed Oil (Curcubita mochata) with Conventional Extraction Methods: Response Surface Methodology for the Optimizing of Ultrasound-Assisted Extraction

Natural products such as natural food are the richest bio-resource of bioorganic compounds for modern medicines, nutraceuticals, food supplements and pharmaceutical applications. The research and application on natural food started with the extraction techniques that play an important role to the extraction quantity (Yield), quality (extracted phytochemicals) and also to the subsequent analyses accomplished to evaluate the biological and chemicals activities. Various types of technologies with different principles of extraction of bioorganic compounds are available today. Based on the literature the conventional extraction methods show better recoveries of bioorganic substances of natural food. Also, conventional extraction methods facilitate the extraction of high concentration of bioorganic substances with the safe solvents system such as pure ethanol. Moreover, conventional extraction methods is still widely used due to its simplicity. However, the conventional extraction methods is not always suitable for industrial uses due to long extraction time and large consumption of harmful solvents systems such as methanol. Therefore, modern non-conventional extraction methods could be an alternative extraction method. Hence, in spite of good results achieved with the conventional extraction methods, modern non-conventional extraction methods was established to search for a faster and better extraction method consuming less solvent, especially those that are unattractive in food industry. This chapter is intended to provide insights on conventional and non-conventional extraction methods with their advantages and disadvantage or limitation.

Background: Thyme (Thymus vulgaris L., Lamiaceae), a medicinal plant with several therapeutic properties. This plant, native to Mediterranean regions, is commonly used as a culinary herb and with a long history of use for various medicinal purposes. Objective: The present study was aimed to examine the physicochemical properties, biological activities including antioxidant and antimicrobial activities of oil extracted from seeds and leaves of common thyme grown in Eastern Ethiopia. Methods: The oil extraction was done using petroleum ether as a solvent. Then, oil quality assessment was done based on the determination of oil content, specific gravity, acid value, percent free fatty acid, peroxide value, ascorbic acid, and free radical scavenging activity using DPPH (2,2-diphenyl-1-picrylhydrazyl) and hydrogen peroxide. The Biological activity was investigated based on antioxidant and antimicrobial activities. The antimicrobial activity was tested using disc diffusion and broth dilution methods. Results: The result of physicochemical properties of T. vulgaris seed oils demonstrated significantly higher oil content (14.75%), specific gravity (0.70±0.50), and peroxide value (1.90±0.14). The antioxidant activities of leaf oil extract presented significantly higher DPPH (22.30±1.27%). The stronger antibacterial activity with maximum zone of inhibition (15.67mm), minimum inhibitory concentration MIC (0.09µg/ml) and minimum bactericidal concentration MBC (0.18µg/ml) were was recorded for leaf oil against S. aureus. The strongest antifungal activity with maximum zone of inhibition (15.33±0.50mm) MIC (0.06 µg/ml), and minimum fungicidal concentration MFC (0.125 µg/ml) against A. niger. Conclusion: The result indicates that leaf oil has stronger antioxidant and antimicrobial potential than seed oil extract.

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 ( 17.00 ± 0.14 %) 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 14.53 ± 0.25 %. 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 80.73 ± 0.08 %, 48.71 ± 0.32 g/g, 24.55 ± 0.42 %, and 91.6 ± 0.49 %, 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.

In this study, phenolic compounds of Kahramanmaraş red pepper (Capsicum annuum L.) seeds which are waste products from red pepper processing line were extracted by ultrasound-assisted (UAE) and conventional solvent extraction (SE) methods. Two different extraction methods were evaluated in terms of total phenolic contents (TPC) and antioxidant capacity. Response surface methodology (RSM) was used to optimize UAE conditions of phenolic extracts including extraction temperature (40, 50 and 60 °C), extraction time (20, 40 and 60 min) and solvent volume (50, 75 and 100 mL) for obtaining maximum total phenolics with higher antioxidant capacity. Effects of temperature, time and volume of solvent on extraction of phenolics were evaluated. As a result of RSM analysis, the optimum conditions determined as an extraction temperature of 51 °C, an extraction time of 60 min, and solvent volume of 50 mL. The results showed that ultrasonic treatment was more effective than conventional extraction method on phenolic extraction yield.

Soybean, wheat germ, sunflower and peanut oils were extracted with supercritical carbon dioxide modified with pentane. The extractions were optimized by chemometric methods using as frontier limits; supercritical pressures of 50 to 150 atm, supercritical temperatures of 60 to 100°C and extraction times of 5 to 15 min. The oils extracted with CO2/pentane were compared to those obtained through conventional extraction methods using hexane.

The application of ultrasonic assisted extraction to extract seed oils for multifaceted food applications is discussed in this study. Seed oils, which are notable sources of health‐promoting characteristics and reservoirs of fatty acids and phytochemicals, are being targeted for effective extraction. Conventional techniques of oil extraction, including mechanical pressing and rendering, have limitations such as low extraction rate, high energy consumption, and low yield. In this context, ultrasonic assisted extraction is green and fast oil extraction technology with a greater extraction rate and low energy consumption. Ultrasound assisted oil extraction is mostly used technique since it is environmentally friendly and can be easily integrated with other extraction processes. Ultrasound‐aided extraction uses less solvent than traditional extraction methods. In this process, cavitation bubbles form in the solvent and burst, causing changes in pressure and temperature that expedite the mass transfer of solutes into solvent. The miscella, including the solvent and oil mixture, is then desolventized using evaporators, followed by steam‐stripping to remove the extracted oil. The current review paper discusses the characteristics of ultrasonic extractions for efficient oil extraction (extraction duration, ultrasound frequency, temperature, solvent employed, and ultrasound type). The conventional and non‐conventional oil extraction methods from sources have been examined in this article, in addition to the ultrasound assisted extraction. Along with traditional and advanced oil extraction techniques, the use of ultrasonication in conjunction with other cutting‐edge techniques is covered in this article.Practical applicationsUltrasound assisted oil extraction extracts oil from vegetables, oilseeds, and nuts by using a suitable carrier. The key parameters influencing ultrasound aided extraction of oilseed include particle shape and size, moisture content of seed, amount of solvent, and extraction time/temperature. The ultimate extraction yield is influenced by the extraction time, operating frequency, operational temperature, solvent type, and proportion, and ultrasonicator design. This technique consumes less energy and requires less maintenance. It is quite efficient and reliable. On this basis, ultrasound aided extraction may be utilized commercially to increase oil extraction rate from oil seeds.

Alternative to traditional olive pomace oil extraction systems: Microwave-assisted solvent extraction of oil from wet olive pomace

Bryophyllum pinnatum is a potential medicinal plant widely used in different tribes in Bangladesh. The leaves of B. pinnatum were used in the present study for the compatibility assessment of a proposed ultrasound-assisted green extraction method with the conventional extraction method. An aqueous Ultrasound-Assisted Extraction (UAE) by using both fresh and dried leaves of B. pinnatum was proposed in the present study and successively compared with the traditional methanolic and aqueous (decoction) extraction method. The promising extraction yield was found through the proposed extraction method which was much better than decoction and almost similar to the methanolic extraction method. Phytochemical contents were also observed similar to the methanolic extract. Both methanolic and UAE extracts obtained from B. pinnatum leaves showed favorable antimicrobial sensitivity against both grams positive (Staphylococcus aureus and Streptococcus pyogenes) and gram-negative (Escherichia coli and Salmonella typhi) bacteria. Extracts obtained from the decoction method showed slightly poor antimicrobial activities. The difference in efficiency and efficacy of aqueous UAE extract obtained from fresh and dried leaves was observed insignificant. This indicates there is no necessity to impart the drying stage before extraction normally practiced in the conventional extraction method. Drying of plant material is a common stage of the conventional extraction cycle which ultimately lengthy the process and impose cost due to energy consumption and labor. Ultrasound-assisted extraction may successfully decrease the overall extraction cycle and ultimately reduce the overall cost of extraction. This method also creates opportunities to replace the water instead of with hazardous organic solvent for phytochemical extraction.

ABSTRACTSafflower seed oil rich in linoleic acid is a kind of functional health oil. The effects of various parameters, such as solvents, liquid–solid ratio and extraction time, on both ultrasonic‐aided and conventional safflower seed oil extractions were investigated through experiments. The results indicated that n‐hexane was a better solvent for the two above‐mentioned extraction methods. Under the following conditions: temperature 35C, liquid–solid ratio 5, extraction time 30 min and ultrasound power 300 W, the oil extraction yield reached 27.02%. However, with the conventional safflower seed oil extraction method, it was only 25.00% when the technical parameters were: temperature 50C; liquid–solid ratio 6; extraction time 60 min. Obviously, the advantages of ultrasonic extraction were as follows: reducing extraction temperature; decreasing solvent quantity; saving time; and improving oil yield. In addition, on the basis of Fick's first law, the kinetic models of ultrasonic extraction and conventional extraction were compared and authenticated. The results showed that a close match was found between experimental data and kinetic equations, and the equations could better simulate safflower oil extraction process. This approach provided a theoretical background for the extraction of safflower seed oil.PRACTICAL APPLICATIONSIn this work, an efficient extraction method – ultrasound‐aided extraction method for safflower seed oil – was acquired. Compared with conventional extraction method, the advantages of ultrasonic extraction were: reducing extraction temperature, decreasing solvent quantity, saving time and improving oil yield. In addition, equipments used in ultrasound‐aided extraction and operation were simple and high efficiency. Therefore, this ultrasonic technology has a brilliant application prospect in extraction of safflower seed oil and other vegetable oils.

BackgroundOil from oleaginous yeasts has the potential to replace non-sustainable vegetable oil as raw material to produce food, feed, biofuels, or biochemicals. Co-produced compounds like carotenoids may be helpful to obtain economically viable bioprocesses. Identifying appropriate extraction methods is a bottleneck both for establishing oleaginous yeasts as cell factories for both oil and carotenoids production and for analysis of intracellular compounds like lipids and carotenoids. We conducted extractions using supercritical carbon dioxide (SC-CO2) and conventional solvent methods to extract and analyze lipids and carotenoids from R. toruloides CBS 14 cells grown on wheat straw hydrolysate. The lipid extracts were analyzed using gas chromatography (GC), and the carotenoids were identified and quantified using ultra-high-performance liquid chromatography (UHPLC).ResultsFour main carotenoids in the extracts from both extraction methods were identified including β-carotene, γ-carotene, torularhodin, and torulene. Interestingly, torularhodin was the major carotenoid extracted using SC-CO2 extraction, followed by torulene. This was different from the conventional acetone extraction method, where β-carotene was the main carotenoid. After the conventional extraction, torularhodin and torulene underwent degradation due to the saponification step, which was necessary to remove lipids before UHPLC analysis. The total carotenoid concentration obtained from SC-CO2 extraction was 332.09 ± 27.32 μg/g dry weight compared to 19.9 ± 2.74 μg/g dry weight in acetone extraction. A small amount of carotenoids was observed to be lost into the lipid extract, but this loss was not as substantial as that seen with acetone extraction. Additionally, the total lipid content in samples extracted using SC-CO2 was significantly lower than that obtained using the conventional Folch method. GC analysis revealed that oleic acid was the major fatty acid in both lipid extracts, followed by palmitic acid and linoleic acid. Notably, the proportion of unsaturated fatty acids was higher in the extracts from the SC-CO2 method compared to the conventional method.ConclusionThese findings indicate that the SC-CO2 extraction method outperformed conventional methods by preserving the integrity of unsaturated lipids and retaining an abundance of carotenoids, resulting in high-quality extracts.

Introduction: Cumin (Nigella Sativa) seed oil extract has some ingredients which have antimicrobial effects. The essential oils present in cumin act as antimicrobial agent and it influence on different type of Gram-negative and Gram-positive bacteria and also viruses, parasites and fungi. This study aimed to investigate the antimicrobial properties of cumin extract in disinfecting dentistry surfaces.
 Material and Methods: This study was performed experimentally and had three groups of cumin extract, Deconex and control group. For each of these groups, 12 culture media were prepared and we counted the colonies created in 24 hours and 48 hours and significance level was assessed using SPSS software and t-test. 
 Results: At 24 hours, there was a significant difference between the bacterial colony counts of the petri dishes from Cumin Seed (Nigella Sativa) Oil Extract at 5.83 and the Deconex at 0. And at 48 hours, there was also a significant difference since the bacterial colony count on the petri dishes with Cumin (Nigella Sativa) Oil Extract was too many to count and a 0.83 bacterial colony count for the petri dishes with the Deconex.
 Conclusion: The Cumin (Nigella Sativa) seed oil extract is not suitable to use as an alternative disinfectant of dental surfaces lonely. But some of its ingredients such as thymoquinone and hydroquinone can be used to produce a disinfecting solution.

Brown seaweeds are rich in fucoidan, a sulfated polysaccharide with antimicrobial, immunomodulatory, antioxidant, and anticancer properties. The brown algae Sargassum sp. has not been thoroughly investigated for fucoidan extraction using various techniques and evaluations of their effects on extraction yield and its structural properties. The purpose of this study was to compare the structural characteristics and extraction yield of fucoidan from Sargassum sp. using conventional, microwave, and ultrasonic-assisted extraction methods. The results showed that a slightly higher yield was obtained by using the ultrasonic-assisted extraction method (2.772%) followed by the microwave-assisted extraction method (2.494%) and conventional extraction method (2.399%). However, the IC50 values for antioxidants were found to be lower (less value is preferable) for crude fucoidan obtained by microwave-assisted extraction method (175 ?g/ml) than for conventional (195 ?g/ml) and ultrasound-assisted extraction methods (230 ?g/ml). The crude fucoidan obtained from the three different extraction methods showed moderate antioxidant strength Contribution to Sustainable Development Goals (SDGs)SDG 3: Good Health and Well-beingSDG 9: Industry, Innovation, and InfrastructureSDG 12: Responsible Consumption and ProductionDG 14: Life Below Water

The efficiency of the green extraction methods ultrasound‐assisted extraction (UAE) and microwave‐assisted extraction (MAE), and conventional methods (Soxhlet and Bligh and Dyer), on lipid content and fatty acid profiles of six fish species (Mullus barbatus, red mullet; Upeneus moluccensis, goldband goatfish; Mullus surmuletus, surmullet; Anguilla anguilla, European eel; Pagellus erythrinus, common pandora, and Saurida undosquamis, brushtooth lizardfish) are evaluated. The results of lipid content of fish species show that the Bligh and Dyer method and UAE in general are more efficient than other methods. There are statistical differences in the fatty acid composition of fish oil by four extraction methods (p < 0.05). Saturated (SFA), monounsaturated (MUFA), and polyunsaturated fatty acid (PUFA) contents of fish species range from 29.51 mg 100 g−1 fish (Soxhlet)–1400 mg 100 g−1 (UAE), 15.52 mg 100 g−1 (UAE)–2237.18 mg 100 g−1 (Bligh and Dyer), and 14.36% (Soxhlet)–646 mg 100 g−1 (Bligh and Dyer), respectively. Generally, Bligh and Dyer give the higher values in surmullet, red mullett, and common pandora in terms of SFA, MUFA, PUFA, and the dominant fatty acids (C16:0, C18:0, C16:1, C18:1n9, C18:1n7, C22:1n9, EPA, DHA), whereas MAE and UAE methods give better results in goldband goldfish and European eel, respectively. Thus, extraction methods affect the lipid yield and fatty acid profiles of extracted oil of different fish species.Practical Application: Total lipid content of seafood is an important parameter used in biochemical, physiological, and nutritional studies. Thus, reliable methods for the quantitative extraction of lipids from this type of food are of critical importance. The effects of green and conventional extraction methods on lipid yield and fatty acid profiles of fish species are compared in order to determine the most effective method for extracting lipid with high yield and high content of PUFA, especially EPA and DHA.The effects of green and conventional extraction methods on lipid yield and fatty acid profiles of fish species are evaluated. The extraction methods affect the lipid yield and fatty acid profiles of extracted oil of fish species. The Bligh and Dyer method and UAE in general are more efficient than other methods. In terms of SFA, MUFA, PUFA, EPA, and DHA; Bligh and Dyer gave the higher values in surmullet, redmullet, and common pandora whereas MAE and UAE methods gave better results in goldband goldfish and European eel, respectively.

Chaga, a sclerotia formed by the Inonotus obliquus fungus, has been widely recognized for a number of medicinal properties. Although numerous scientific investigations have been published describing various biological activities of chaga from different geographical locations, little work has focused on chaga harvested in the USA or extraction techniques to maximize anti-inflammatory properties. The aim of this study was to investigate the anti-inflammatory properties of chaga collected in Maine (USA) extracted using traditional aqueous (hot water steeping) methods against lipopolysaccharide (LPS)-induced RAW 264.7 macrophages. Chaga extracts obtained from both conventional (ethanol/water) extraction methods and an accelerated solvent extraction method (ASE) at optimized conditions were compared to aqueous extracts (tea) obtained from chaga in the powder form (P) and powder form in tea bags (B) based on their effect on both nitric oxide (NO) production and pro-inflammatory cytokine expression, in particular, the expression of TNF-α, interleukin-6 (IL-6), and interleukin-β (IL-1β). Phenolic acid extracts from chaga and individual phenolic acid standards were also investigated for their effect on the same parameters. Results indicated that various chaga extracts have significant anti-inflammatory activity on LPS-stimulated RAW 264.7 cells. The inhibitory effect was through a decrease in the production of NO and the downregulation of TNF-α, IL-6, and IL-1β in RAW 264.7 macrophages. ASE1 (novel, optimized ethanol/water extraction) and P6 (six-minute steeping of powder in 100 °C water) extracts showed the highest inhibitory activity on NO production and on the expression of the inflammatory cytokines, compared to extracts obtained by conventional extraction methods.

Recently, there has been an increasing interest for the oils from unconventional plant seeds with growing health awareness among consumers. These oils are considered as a source of dietary or specialty oils with their valuable functional components. Specialty oils obtained from unconventional plant seeds are one of the richest sources of natural bioactive compounds such as tocopherols, squalene, carotenoids, phytosterols, and phenolic compounds. The high levels of those bioactive lipids are of importance in nutritional and pharmaceutical applications. Epidemiological researches have demonstrated that many of these bioactive compounds possess anti-inflammatory, anti-atherosclerotic, antitumor, antimutagenic, anticarcinogenic, antibacterial, or antiviral activities to a greater or lesser extent. Thus, researchers have recently focused on the new sources of unconventional plant seed oils and their bioactive compounds and nutraceutical effects. The seeds of black cumin, sesame, flax, nettle, pomegranate, grape, and pumpkin are the most common specialty oil sources that are used in alternative and folk medicine to prevent some chronic diseases and also improve immune function. Extraction method of unconventional seed oils is a key factor to obtain high-quality oils preserving their biologically active compounds. Today, there is much interest in novel, clean, and promising techniques to extract seed oils including higher concentration of bio-compounds overcoming the limitations of conventional extraction methods. This chapter summarizes the specialty plant seed oils, their bioactive compounds and functional and nutraceutical properties, as well as the novel extraction methods.