Kinetic Study of Subcritical Water Extraction of Scopoletin, Alizarin, and Rutin from Morinda citrifolia

Noni fruits (Morinda citrifolia) are a source of phenolic bioactive compounds (scopoletin, alizarin, and rutin), which have antioxidant, antimicrobial, anticancer, and anti-inflammatory activities. In this study, subcritical water was applied to determine the extraction yields and kinetics of phenolic compounds from noni fruits. The scopoletin and alizarin yields increased with the increase in temperature from 100 to 140 °C, while that of rutin increased up to 120 °C and then decreased at 140 °C. The yields of all the compounds rapidly increased from 1 to 2 mL/min and then slightly up to 3 mL/min of water flow rate. The extraction kinetics were assessed using two mathematical models. The two-site kinetic desorption model had a better fit for all experimental conditions throughout the extraction cycle and best described the extraction kinetics of phenolic compounds from noni fruits. The diffusion coefficients of scopoletin and alizarin at 140 °C and 3 mL/min were 3.7- and 16.2-fold higher than those at 100 °C and 1 mL/min, respectively. The activation energies of alizarin were 2.9- to 8.5-fold higher than those of scopoletin at various flow rates. Thus, subcritical water could be an excellent solvent with higher extraction yields and shorter extraction times using an environmentally friendly solvent.

Effect of process parameters on the antioxidant activity of Vietnamese tea (Camellia sinensis O. Kuntze) seed oil

This research was carried out on Tea (Camellia sinensisO. Kuntze.) seeds (containing 22.01% oil) harvested from Trung du tea trees varieties, cultivated in Phu Tho, Vietnam to select the most suitable processing methods which enhance the high antioxidant activity of the oil in the seed oil extraction. The objective of this research is to study the effects of particle size, material/solvent ratio, temperature, time, speed of solvent movement, and extraction cycle on antioxidant properties of the oil (by analysing IC50, total polyphenol content, total carotenoid, and total tocopherol value). The suitable extraction conditions were determined as follows: particle size was 0.25-0.5 mm, the solid-solvent ratio was 1/8-1/10, the extraction temperature was 35-45oC, the extraction time was 7-9h, speed of solvent movement was 200-250 r/m and the extraction cycle was two times. The tea seed oil extracted under the suitable conditions had the DPPH radical scavenging activity (IC50), total polyphenol content, total carotene, and total tocopherol of 62.19 mg/ml, 4.45 mgGAE/g dry weight, 89 mg/kg, and 710 mg/kg, respectively. The high content of antioxidants makes tea seed oil has a good antioxidant capacity, high oxidation stability, and relatively long shelf life. Therefore, research on using wasted tea seed sources to extract oil has great potential for the vegetable oil industry and a high potential of application in food technology.

EVALUATION OF THE DURATION OF THE EXTRACTION CYCLE OF LUMP PEAT BY THE CALCULATION METHOD AND ON THE BASIS OF PRODUCTION DATA

The results of the determination of the duration of the cycle of the extraction of lump peat by the calculation method and on the basis of the data obtained in production conditions are presented. The dynamics of drying of lump peat with a diameter of 40 mm under conditions of a radiation-convective regimes is studied. The influence of the intensity of precipitation on the technological and operational indicators of the production of molded products is shown. It was revealed that the coefficient of variation of the number of cycles, one of the main indicators, for a three-year observation period was 33,0 %, which, according to the accepted gradation, is a significant value. As a result of a review of published works, it was found that the average long-term climatic data obtained in the 1960s–1970s and used in the calculations of drying of lump peat in a radiation-convective regimes differ significantly from the data observed during modern climate warming.

Effect of accelerated solvent extraction conditions on the isolation of bioactive compounds from fennel (Foeniculum vulgare Mill.) seeds

This study focused to establish the optimal conditions of accelerated solvent extraction (ASE), i.e., temperature, static extraction time and number of extraction cycles, for the isolation of fennel (Foeniculum vulgare Mill.) seeds phenols and pigments using 96% ethanol as an extraction solvent. Hence, extraction conditions of temperature (80 and 110 °C), static extraction time (5 and 10 min) and number of extraction cycle (1, 2, 3 and 4) were varied. Obtained extracts were spectrophotometrically analyzed for the content of total phenols (TP), total chlorophylls (TCHL) and total carotenoids (TCAR). Applied extraction conditions had a significant (p<0.01) influence on the yields of analyzed compounds, except for static extraction time on TCAR (p=0.11). Based on the results of statistical analysis, the highest levels of TP and TCHL were achieved at the most invasive conditions (110 °C/10 min/4 cycles), while shorter period was sufficient to reach the highest TCAR yield (110 °C/5 min/3 cycles). In summary, ASE demonstrated to be effective extraction technique for the isolation of fennel seeds hydrophilic and lipophilic bioactive compounds.

Effects of Various Processing Parameters on Polyphenols, Flavonoids, and Antioxidant Activities of Codonopsis javanica Root Extract

The root of a ginseng-like plant named Codonopsis javanica is a valuable ingredient in folk medicine with diverse biological properties and has been used in treatments for various diseases, including leukemia, inflammation, and hepatitis. This study aimed to optimize various parameters related to the extraction process of C. javanica root (CJR) with respect to total phenolic content (TPC), total flavonoid content, and antioxidant activities of the obtained CJR extract. We first performed a series of single-factor investigations taking drying conditions and different extraction parameters such as material size, extraction solvent, solvent concentration, extraction temperature, material/solvent ratio, extraction cycle, and stirring speed as varying factors. Then, a response surface methodology procedure was adopted with a central composite design to optimize further the extraction process in order to maximize the TPC. We found that the use of convection drying at 70 °C for 8 hours gave the extract with the highest TPC and antioxidant activities. Optimal extraction parameters were found as follows: ethanol with a concentration of 56.0% as the solvent, material-to-solvent ratio of 1/38.0 g/mL, extraction time of 67.2 minutes, material size ≤0.5 mm, temperature 60 °C, through 1 extraction cycle, and with a stirring speed of 300 rpm. Under the optimized conditions, the experimental value for TPC was 2.9 mg gallic acid equivalent (GAE)/g dry weight (DW), which is reasonably close to the value predicted by the model (2.8 mg GAE/g DW). The half-maximal inhibitory concentration (IC50) values determined by the 2,2-diphenyl-1-picrylhydrazyl and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid free radical tests of the CJR extract obtained under optimal conditions were 1042.3 and 299.0 µg/mL, respectively.

High Yields of Shrimp Oil Rich in Omega-3 and Carotenoids: Extending to Shrimp Waste the Circular Economy Approach to Fish Oil Extraction

A shrimp oil rich in omega-3 lipids and carotenoids is obtained in remarkably high 5 wt% yield extending to pink shrimp processing waste (head and carapace) the circular economy approach to extract fish oil from fish processing by-products using d-limonene. Biobased limonene, a powerful antimicrobial and antioxidant agent, is an excellent solvent for both lipids and astaxanthin-based carotenoids preventing oxidative degradation during the extraction cycle including solvent and oil separation at 85°C. A new low cost route is established to extract valued marine oil from biowaste annually made available in over 2.2 million tonnes.

GC/MS chemical analysis of lavandin (Lavandula x intermedia) hydrolat: Successive extraction fractions

Hydrolats are valuable co-products of the essential oil distillation process, whose volatile compounds can be quantified by various methods. In this paper, we have tried to estimate the liquid-liquid extraction cycle number threshold for volatile compounds quantification of lavandin (Lavandula x intermedia) hydrolat. For this purpose, ten consecutive hydrolat extractions with n-hexane were analyzed GC/MS with hexadecane (C16) as an internal standard and compared with the lavandin essential oil. The chemical composition of the lavandin hydrolat showed similarity with its essential oil to the great extent, while volatile compounds dissolved in hydrolat exclusively belonged to the class of oxygenated monoterpenes. The total amount of extracted compounds has been estimated to 2174.2 mg/L, where the most dominant compounds in lavandin hydrolat were cisand trans-furanoid linalool oxide (676.3 and 634.1 mg/L, respectively), followed by much smaller amounts of linalool, camphor, and 1,8-cineole (167.6, 157.0, and 148.2 mg/L, respectively). Cumulative recoveries of total compounds yield after the third, fifth, and eighth extractions were 88 %, 96 %, and 99 %, respectively. Combined fraction analysis confirmed that in the first 5 cycles more than 95 % of the total yield (from 10 cycles) of extracted volatile compounds can be collected. Based on the results of this study, for volatile compounds quantification in lavandin hydrolat, 5 cycles of n-hexane liquid-liquid extraction can be recommended.

EFFECTS OF PROCESS PARAMETERS ON THE EXTRACTION EFFICIENCY AND CHEMICAL CHARACTERISTICS OF TEA SEED OIL FROM “TRUNGDU” TEA VARIETY

This research was aimed at investigating the effects of some extraction process parameters on the extraction efficiency and some chemical characteristics of tea seed oil from “Trungdu” tea variety, one of the high-quality vegetable oils, similar to olive oil with high portion of unsaturated fatty acids, especially essential linoleic acid and low content of saturated fat. This work reports for the first time the effects of process parameters using solvent extraction method on the efficiency and chemical characteristics of “Trungdu” tea seed oil. The study parameters were particle size (0.25-2.00 mm), material/solvent ratio (1/12-1/6), temperature (25-55oC), time (5-11 h), speed of solvent movement (0-250 r/m) and extraction cycle (1-3 times). The responses such as extraction efficiency, chemical characteristics (acid, peroxide, iodine and saponification values) were determined. The results indicated that the extraction efficiency was affected by all designed parameters. In addition, the temperature, particle size and extraction time had the most significant effect on the iodine value and acid value. The extraction temperature and the speed of solvent movement had pronounced effects on all the acid value, peroxide value, iodine value and saponification value of tea seed oil. However, ratio of material/solvent and extraction cycle did not appreciably effect on chemical characteristics of tea seed oil. Furthermore, the optimal extraction efficiency related to higher quality properties had been achieved in the range of 35 to 45oC, 7 to 9 hours, with a particle size of 0.5 mm, material/content ratio 1/8 to 1/12, movement speed of solvent 200 to 250 r/m and extraction cycle 1 or 2 times. Therefore, the results from this work will be useful for developing an optimal procedure for obtaining tea seed oil. In addition, tea seed oil with the main acid component is oleic acid and linoleic acid, is considered a high quality oil.

Review of Alternative Solvents for Green Extraction of Food and Natural Products: Panorama, Principles, Applications and Prospects

In recent years, almost all extraction processes in the perfume, cosmetic, pharmaceutical, food ingredients, nutraceuticals, biofuel and fine chemical industries rely massively on solvents, the majority of which have petroleum origins. The intricate processing steps involved in the industrial extraction cycle makes it increasingly difficult to predict the overall environmental impact; despite the tremendous energy consumption and the substantial usage of solvents, often the yields are indicated in decimals. The ideal alternative solvents suitable for green extraction should have high solvency, high flash points with low toxicity and low environmental impacts, be easily biodegradable, obtained from renewable (non-petrochemical) resources at a reasonable price and should be easy to recycle without any deleterious effect to the environment. Finding the perfect solvent that meets all the aforementioned requirements is a challenging task, thus the decision for the optimum solvent will always be a compromise depending on the process, the plant and the target molecules. The objective of this comprehensive review is to furnish a vivid picture of current knowledge on alternative, green solvents used in laboratories and industries alike for the extraction of natural products focusing on original methods, innovation, protocols, and development of safe products.