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Pressurized hot water extraction of phenolic and antioxidant activity of Clinacanthus nutan leaves using accelerated solvent extractor
Abstract
To Cite This Article: N.A.F Baharuddin, M.F.M Nordin, N.A Morad, N.A Rasidek., Pressurized hot water extraction of phenolic and antioxidant activity of Clinacanthus nutan leaves using accelerated solvent extractor. Accelerated solvent extractor (ASE) is classified as the Pressurized Hot Water Extraction (PHWE) which is known as green extraction process mainly used for bioactive extraction from plant matrices. In the present work, 'belalai gajah' leaves or Clinacanthus nutan was used for extraction of phenolic compound and antioxidant activity using ASE. In this study, the effect of temperature and time on total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (AA) was investigated. Operating variable consists of temperature ranging from 100 to 180°C and time 5 to 30 minutes; at 1500psi. The results indicate the highest TPC was obtained at 160°C, 5 minutes with value of 20.97 ± 0.03 mg gallic acid g-1 dry sample and TFC was found highest, 20.99 ± 0.01 mg quercetin g-1 dry sample at 180°C, 30 minutes. Meanwhile, greatest AA achieved till 68% at 180°C, 5 minutes. Thus, the TFC in C. nutans contribute more to antioxidant activity than TPC with R 2 more than 80%. TFC can be used as a guidance in assessing the antioxidant activity of herb plants. From this study, the present investigation reveals that TFC is mainly responsible for DPPH free radical scavenging capacity.
... Several reports are available in which ASE is applied to extract phenolic compounds. 62,63 Very recently, the accelerated solvent extraction (ASE) method was compared to conventional ultrasonic-assisted extraction (UAE) and solvent extraction (CSE) methods, and interestingly the ASE was found to be more appropriate and efficient among all three methods for the extraction of anthocyanin and total phenolic compounds. 64 3.2.5 Supercritical uid extraction. ...
Chalcones, a class of secondary metabolites within the flavonoid family, are characterized by a distinct C6-C3-C6 structure. They are prevalent in both edible and medicinal plants and serve as critical precursors in the flavonoid biosynthesis pathway. Structurally, chalcones are α,β-unsaturated ketones known for their significant bioactive properties which lend them therapeutic potential for a variety of bioactivities. Research into the bioavailability of chalcones and their derivatives has revealed both potential barriers and enhancements regarding their use in nutraceutical and pharmaceutical contexts. The current review provides a comprehensive discussion on the biosynthesis, chemistry, natural occurrence—especially in medicinal and dietary plants, bioavailability, and important roles of chalcones and their derivatives. Moreover, it delves into the toxicological and pharmacological properties of chalcone derivatives, covering their antioxidant, anticancer, antidiabetic, anti-inflammatory, antimalarial, antimicrobial, immunosuppressive, and neuroprotective effects. There is a call for further research to clarify their structure–activity relationships, address toxicity concerns, understand the cellular mechanisms behind their actions, and explore their interactions with other molecules.
... Both studies suggested that the greater antioxidant activity of the leaf extract was attributed to its higher amount of phenolic and flavonoid compounds. This study also further substantiated the finding of Baharuddin et al. (2017) where good antioxidant activity of C. nutans leaves was attributed to their flavonoid content. A significant correlation between total flavonoid contents and DPPH activity in C. nutans was also reported by Ghasemzadeh et al. (2014) and they noted that the antioxidant activity of C. nutans leaf was attributed to its flavonoid content. ...
Clinacanthus nutans (Burm.f.) Lindau is a valuable medicinal plant that has gained interest as a side treatment for cancer in Southeast Asia. Phenolic and flavonoid compounds identified in this plant have been linked to anti-cancer properties. However, quantification of such metabolites in plants varies depending on cultivation methods and conditions resulting in inconsistent yield. This study aims to establish cell suspension culture of C. nutans, evaluate the accumulation of phenolics, flavonoids and to assess the antioxidant activity of extracts from in vitro cultures. Callus was induced from leaf explants of C. nutans and proliferated on Murashige & Skoog (MS) medium supplemented with different combinations of plant growth regulators (2,4-dichlorophenoxyacetic acid, 6-benzylaminopurine and kinetin). Assessment of growth kinetics for the suspension culture was performed. The total phenolic, flavonoid contents and antioxidant activity of the extracts were evaluated followed by high-performance liquid chromatography (HPLC) to detect selected flavonoids. MS medium supplemented with 0.25 mg/L 2, 4-D and 0.25 mg/L BAP was optimal for callus induction, proliferation and suspension cultures. The highest total phenolic content was obtained from suspension cells (55.35 mg GAE/g DW) whereas leaf showed the highest flavonoid content (25.13 mg QE/g DW). Leaf extract demonstrated the strongest antioxidant activity with the lowest IC50 value (117.42μg/mL). HPLC analysis revealed the presence of catechin, luteolin, quercetin and kaempferol in the suspension cells and the leaf. The present study indicated that cell suspension cultures are able to accumulate higher phenolic compounds and possess all four selected flavonoids similar to the outdoor grown plant.
... Previous studies have reported that the C. nutans extracts possess anticancer and antioxidant properties in various cancer cell lines in vitro; nevertheless, their antioxidant and antitumor activities have not been completely elucidated in murine models [25][26][27]. Therefore, our experiments have shown that the methanolic extract of C. nutans leaves could inhibit the tumor progression in 4 T1 tumor-bearing mice model. ...
Abstract Background Clinacanthus nutans Lindau (C. nutans) is a species of in Acanthaceae family and primarily used in South East Asian countries. C. nutans is well known as Sabah snake grass in Malaysia, and its leaves have diverse medicinal potential in conventional applications, including cancer treatments. On the basis of literature search, there is less conclusive evidence of the involvement of phytochemical constituents in breast cancer, in particular, animal tumor models. The current study aimed to determine the antitumor and antioxidant activities of C. nutans extract in 4 T1 tumor-bearing mice. Methods C. nutans leaves were subjected to methanol extraction and divided into two different concentrations, 200 mg/kg (low-dose) and 1000 mg/kg (high-dose). The antitumor effects of C. nutans extracts were assessed using bone marrow smearing, clonogenic, and splenocyte immunotype analyses. In addition, hematoxylin and eosin, tumor weight and tumor volume profiles also used to indicate apoptosis appearance. Serum cytokine levels were examined using ELISA assay. In addition, nitric oxide assay reflecting antioxidant activity was performed. Results From the results obtained, the methanol extract of C. nutans leaves at 200 mg/kg (P
... PHWE refers to the extraction with water under pressure at the temperature between the boiling and critical temperature (100 and 374 °C respectively) [8]. The extraction of the bioactive compounds in plants could be affected by the plant species, extraction temperature, time, water-sample ratio and/or pressure4, [9,10,11]. This research focuses on the extraction of D. esculentum active compounds which contribute to DPPH antiradical activity. ...
Pressurized hot water extraction (PHWE) was implemented in attempt to reduce the use of toxic organic solvent in extracting bioactive compounds from Diplazium esculentum. The antioxidant assays, which were the DPPH scavenging activity, total phenolic contents and total flavonoid contents were analyzed on PHW extracts. By applying Box-Behnken design under response surface methodology (RSM), the optimized condition for the best antioxidant activity of PHWE was at 175 °C, 21 min extraction time and 50 mL water volume added to 2 g of dried D. esculentum. The DPPH antiradical efficiency of D. esculentum give EC50 values of 1241.14 μg/mL and time to reach steady state (TEC50) was 79.83 min. Thus, the extract was categorized as slow in scavenging the DPPH free radicals.
Response surface methodology is a series of statistical techniques that can be used to design experiment, modeling and evaluating the effect of variables on the final obtained results and optimization of process conditions. In this research, optimization of the solvent extraction method of bioactive compounds from seedless barberry (Berberis vulgaris) was carried out using response surface methodology. Central composite design was employed with 13 treatments and 5 replications in central points and the effect of variable factors of temperature (50-70ºC) and extraction time (40-120 minutes). The amount of anthocyanin content, vitamin C, phenolic contents and antioxidant activities of extracted barberry were measured. Close agreement was found between experimental and predicted values of model. Effects of extraction temperature and time were found to be significant on all responses. According to these results, optimal extraction conditions were identified at 50 °C temperature for120 minutes. In this condition the maximum of phenolic compounds, anthocyanin, antioxidant activities and vitamin C contents were 585.725 mg GAE/100ml, 208.392 mg/l, 84.2603% and 1292.56 ppm respectively. The results showed that this methodology could be applied in the extraction of bioactive compounds in the natural product industry.
Background
Clinacanthus nutans (Burm. f.) Lindau leaves are widely used by cancer patients and the leaf extracts possess cytotoxic and antiproliferative effects on several human cancer cell lines. However, the effect of C. nutans leaf extract on human melanoma, which is the least common but most fatal form of skin cancer and one of the most common cancers diagnosed in both sexes worldwide, is unknown. There is also limited information on whether the bioactivity of extracts differs between C. nutans leaves grown in different geographical locations with varying environmental conditions. Methods
The present study, for the first time, compared and demonstrated the cytotoxicity of the crude methanol extracts of C. nutans leaves from 11 different locations in Malaysia, Thailand and Vietnam, with diverse environmental conditions against D24 melanoma cells through WST-8 assay. The percentage of apoptotic cells following treatment with the most active extract was determined in a dose- and time-dependent manner by a cytofluorometric double staining technique. Biochemical and morphological changes in the treated and untreated cells were examined by fluorescence and transmission electron microscopy techniques, respectively, to further affirm the induction of apoptosis. ResultsThe leaves of plants grown at higher elevations and lower air temperatures were more cytotoxic to the D24 melanoma cells than those grown at lower elevations and higher air temperatures, with the leaf extract from Chiang Dao, Chiang Mai, Thailand exhibited the highest cytotoxicity (24 h EC50: 0.95 mg/mL and 72 h EC50: 0.77 mg/mL). This most active crude extract induced apoptotic cell death in the D24 cells in a dose- and time-dependent manner. Typical biochemical and morphological characteristics of apoptosis were also observed in the treated D24 cells. Conclusions
The results, showing the cytotoxicity of C. nutans and the induction of apoptosis in D24 cells, are significant and useful to facilitate the development of C. nutans as a potential novel chemotherapeutic agent for the management of skin melanoma.
Elephantopus scaber and Clinacanthus nutans are traditionally used as wound healing herb. The objective of the present study is to develop a new polyherbal formulation, by comparison, the herbal combination of Elephantopus scaber and Clinacanthus nutans as an in vitro antioxidant activity with their individual herbal activity followed by fractionation of polyherbal formulation for in vivo wound healing activities and identification of bioactive compounds from their active fractions. Antioxidant activity was performed in vitro by DPPH scavenging antioxidant activity followed by in vivo wound healing activities using excision wound model, incision wound model, and burn wound model. Toxicity of the fractions of the polyherbal formulation was performed by a dermal toxicity test. The result showed that Elephantopus scaber crude extract on the basis of EC 50 performs a much faster action (15.67 í µí¼g/mL) but with less % inhibition (87.66%) as compared to the combination of the new polyherbal formulation of crude extract (30 í µí¼g/mL). The polyherbal formulation has the highest % inhibition (89.49%) at the same dose as compared to Elephantopus scaber (87.66%). In comparison among all crude and fractions of new polyherbal formulation, it was found that the ethyl acetate fraction of polyherbal formulation has the fastest activity (EC 50 14.83 í µí¼g/mL) with % inhibition (89.28%). Furthermore, during evaluation of wound contraction on excision and incision wound model, ethyl acetate fraction possesses the highest activity with (P < 0.001) and (P < 0.0001), respectively. During burn wound model, aqueous fraction (P < 0.001) possesses the highest activity followed by an ethyl acetate fraction (P < 0.0001). LC-MS analysis discovered the presence of several flavonoid-based compounds that work synergistically with sesquiterpene lactone and other bioactive compounds. In conclusion, flavonoid increases the antioxidant activity that surges the rate of wound contraction and works synergistically with other bioactive compounds.
An increasing demand for natural additives has drawn more interest from consumers due to their relatively safe and wide acceptance. The present work examines the potential of different solvent system of Clinacanthus nutans Lindau leaves as a source of natural antioxidant. We also screened for its phytochemical constituents and cytotoxicity toward breast cancer cell. In vitro antioxidant activity of the n-hexane, dichloromethane, ethyl acetate, and ethanol extracts were assessed via 1,1-diphenyl-picrylhydrazyl (DPPH) radical scavenging activity, oxygen radical absorbance capacity and ß-carotene bleaching activity assays, whereas the cytotoxic effect was tested on tumorigenic breast cancer estrogen positive cell (MCF-7) and normal fibroblast cell (3T3) using the tetrazolium assay. Liquid chromatography mass spectrometry equipped with an electrospray ionization source liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI/MS) was used to analyze the amount of targeted phenolic and fatty acids in ethanol and ethyl acetate extracts. Several phenolic compounds and fatty acids were identified and quantified from ethanol and ethyl acetate extracts of this plant. Ethanol and ethyl acetate extracts demonstrated stronger antioxidant activity than n-hexane and dichloromethane extracts (p<0.05). Thus, ethanol and ethyl acetate extracts of C. nutans may be explored as new sources of antioxidants in herbal medicines research.
Physalis angulata, having familiar name in Indonesia as “Ceplukan”, is wellknown empirically in folk medicineto treat several diseases such as hepatitis, malaria, boil, liver problem, diuretic etc. Clinically several researchershave revealed the activity of Physalis angulata extract as anticancer, antitumor, antimycobacterial,immunosuppresion etc. So far, the common method to obtain Physalis angulata extract is by hot waterextraction (HWE) and maceration using organic solvent such as methanol or ethanol. Meanwhile, strickerregulation of organic solvent residue to the pharmaceutical product encourages the research to replace organicsolvent by environmentally benign solvent. The objective of this research is to investigate the potential ofPhysalis angulata leaves extract obtained by Subcritical Water Extraction (SWE) method as antioxidantThe Physalis angulata leaves were extracted by water in subcritical condition. Water in this condition may havepolarity similar with organic solvent, so it can extract the phytochemical in plant material. Three variables wereinvestigated including pressure (100-200 bar), temperature (100-250oC) and extraction time (15-45 min). Afterevaporating the water, the extracts were analyzed for antioxidant activity, total phenol and flavanoid usingspectrophotometer. Water content in extract was analyzed by karl fischer titrator. The result revealed thatpressure has negligible effect, while temperature has significant effect to the antioxidant activity, total phenol andflavanoid content. The results also compared with that of obtained by conventional methods such as maceration(water and ethanol), HWE and soxhlet.
The purpose of this review is to give the reader a thorough background to the fundamentals and applications of pressurized hot water extraction (PHWE) for the analysis of bioactive compounds. We summarize the field in the period 2009–14, and include fundamentals of water as a solvent: equipment; method optimization; applications; coupling; and, future prospects. We highlight that solvent properties of water are tunable by changing the temperature, particularly self-ionization, dielectric constant, viscosity, diffusivity, density and surface tension. Furthermore, important aspects to consider are the risk of degradation of the analytes and other potential reactions, such as hydrolysis, caramelization and Maillard reactions that may lead to erroneous results. For the extraction of bioactive compounds, we report PHWE methods based on using water of 80–175°C and short extraction times. In conclusion, PHWE provides advantages over conventional extraction methods, such as being “greener”, faster and more efficient.
Bitter melon, Momordica charantia L, is a popular traditional medicinal fruit in tropical and subtropical countries. It has been linked with therapeutic effects, some of which are likely due to its flavonoids. To determine its total flavonoid content (TFC) and to prepare extracts for use as nutritional supplements or ingredients for nutraceutical functional foods, various solvents have been used, including water, which is the preferred solvent because it is inexpensive, safe and environmentally friendly. The study aimed to extract bitter melon, using five solvents (ethanol, methanol, n-butanol, acetone and water) before and after the optimal conditions for water were determined in terms of extraction temperature, time, ratio of water to bitter melon (mL/g) and number of times the same material was extracted. The TFC of six varieties of bitter melon was also determined. Acetone was the best of the five solvents for extracting flavonoids from the Moonlight variety (23.2 mg Rutin Equivalents (RE)/g). Even after increasing the extraction by 88% (1.24 vs 0.66 mg RE/g) using optimised conditions for the aqueous extraction (two extractions at 40˚C for 15 min at a ratio of 100:1 mL/g of bitter melon powder), the fla-vonoids extracted from the Moonlight variety using water was very little (5.4%) compared to acetone. Furthermore , using acetone, it was shown that the Moonlight variety (23.2 mg RE/g) bought at a local market had higher levels of flavonoids than the greenhouse-grown Jade (15.3 mg RE/g), Niddhi (16.9 mg RE/g), Indra (15.0 mg RE/ g), Hanuman (3.9 mg RE/g) and White (6.9 mg RE/g) varieties. Therefore, acetone was the best solvent for extracting flavonoids from bitter melon and the aqueous extraction could only be improved to extract 5.4% of the flavonoids extracted with acetone from the Moonlight variety, which had the highest TFC of the six varieties of bitter melon.
Clinacanthus nutans is widely known in traditional medicine in Malaysia and Thailand due to its medicinal properties in treating skin rashes, insect and snake bites, and skin lesions caused by virus. Many studies have been carried out to investigate the bioactivities of C. nutans extracts against a number of diseases. The findings showed that the extracts of C. nutans possessed analgesic, anti-oxidant, anti-inflammatory and anti-viral activities against HSV-1, HSV-2, VZV and HPV. These effects are probably due to the composition of the plant that contains stigmasterol, lupeol, β-sitosterol, betulin, C-glycosyl flavones, sulfur-containing glucosides, glycoglycerolipids, a mixture of nine cerebrosides and monoacylmonogalactosylglycerol. Even though C. nutans has been extensively used as primary sources of complementary and alternative healthcare for cancer patients in Malaysia, the scientific proof of its anti-cancer property remains insufficient. Moreover, the health products of this plant are less popular in the northern region of Peninsular Malaysia. Therefore, comprehensive investigations on C. nutans extracts against cancers are necessary to understand its anti-cancer mechanisms, to encourage investigations on this plant, as well as to promote this plant as an economical regimen for the treatment of diseases, including cancers, to the patients in this region.
http://ijib.classicrus.com/trns/219611448342330.pdf
Breast cancer is the second leading cause of death from cancer in women in the United States. A growing emphasis is being placed on alternative medicine and dietary approaches toward prevention of potential diseases. Phytochemicals are bioactive compounds that are naturally present in foods that, when acting in synergy, bestow potential anti-cancer properties. Resveratrol, a phytoalexin, and ursolic acid, a pentacyclic triterpenoid, are two bioactive compounds that are at the forefront in scientific research. Previous animal studies have documented the anti-cancer properties of resveratrol on breast cancer cells and research groups have recently been able to identify the anti-cancer, anti-inflammatory and induction of apoptosis properties of resveratrol along with the signal transduction pathways that the compound affects. Ursolic acid has been cast into the limelight with the recent discovery documenting its anti-inflammation and anti-cancer activities by targeting signal pathways, especially in the prevention of breast cancer.
The optimization of the extraction of anthocyanins and other phenolic compounds from jabuticaba skins, a promising Brazilian source of these compounds, was studied using pressurized liquid extraction (PLE). An optimization study was performed using ethanol as a solvent and with extraction pressure (5–10 MPa), temperature (313–393 K) and static extraction time (3–15 min) as independent variables. The optimum PLE conditions for all response variables were estimated; however, PLE conditions resulting in the highest recovery of anthocyanins (5 MPa, 553 K and 9 min of static extraction time) were chosen for comparison with a conventional low-pressure solvent extraction (LPSE). The attributes compared were yield, content of anthocyanins and phenolic compounds and economic feasibility. Similar extraction yields were obtained by LPSE and PLE under optimized conditions; however 2.15 and 1.66-fold more anthocyanins and total phenolic compounds, respectively, were extracted using PLE, while the cost of manufacturing (COM) obtained for the PLE extract was 40-fold lower.
Hot compressed water extraction (HCWE) is a promising alternative technology which has proven to be successful in many applications. In this study, hot compressed water extraction (HCWE) was applied in the extraction of crude palm oil (CPO) from palm mesocarp. The operating conditions investigated were pressure of 30, 40 and 50 bar with varied temperature ranging from 120 to 180°C through semi-batch extraction of 10 mins interval and total extraction time of 60 mins. The CPO yield, free fatty acids (FFA) content through HCWE process was analysed. Scanning electron microscopy (SEM) study on various palm mesocarp fibres undergone HCWE process at various conditions was also performed. The extracts formed three distinguished layers; oil, oil-water emulsion and water. The maximum CPO extracted in the oil layer was 0.541 ± 0.005 (g-oil/ g-dried mesocarp) with averaged FFA of 0.81 ± 0.08% at the optimum operating condition of 160°C and 50 bar. CPO recovered from the emulsion was 0.159 ± 0.004 g-oil/ g-dried mesocarp giving a total CPO extracted at 0.700 ± 0.005 g-oil/ g-dried mesocarp. SEM micrographs were used to assist understanding of the mechanism that took place during the experimental conditions of HCWE. The time dependence of the compounds was well represented by the second order mass transfer model. The mechanism of CPO extraction from palm mesocarp using HCWE was also explained through this study.
Clinacanthus nutans Lindau is known as snake grass belonging to the Acanthaceae family. This plant has diverse and potential medicinal uses in traditional herbal medicine for treating skin rashes, insects and snake bites, lesions caused by herpes simplex virus, diabetes, and gout in Malaysia, Indonesia, Thailand and China. Phytochemical investigations documented the varied contents of bioactive compounds from this plant namely flavonoids, glycosides, glycoglycerolipids, cerebrosides and monoacylmonogalatosylglycerol. The pharmacological experiment proved that various types of extracts and pure compounds from this species exhibited a broad range of biological properties such as anti-inflammatory, antiviral, antioxidant, and anti-diabetic activities. The findings of toxicity study showed that extracts from this plant did not show any toxicity thus it can be used as strong therapeutic agents for specific diseased conditions. However, further experiments on chemical components and their mode of action showing biological activities are required to elucidate the complete phytochemical profile and assess to confirm their suitability for future drugs. This review summarizes the medicinal uses, phytochemistry and pharmacology of this plant in order to explore its therapeutic potential and gaps necessitating for prospected research work.
The composition and bioactivity of natural plant extracts strongly depends on the extraction technique employed. Clinacanthus nutans Lindau (C. nutans) is a well-known medicinal plant in South-East Asia that has been traditionally used for treatment of hepatitis, skin-rashes and snake venom poisoning, and recently has attracted attention for its applications for treatment and prevention of cancer diseases. In previous studies, the extraction of bioactive compounds from C. nutans by conventional Soxhlet solvent extraction has been described, but this method shows limitations in terms of selectivity, extraction yield and toxicity of the solvents employed. In this study, phytochemical compounds were extracted from leaves and stems of C. nutans by microwave-assisted extraction (MAE), pressurized microwave-assisted extraction (PMAE), supercritical carbon dioxide extraction (SFE) and Soxhlet method to investigate the best technique in terms of yield, extraction time and recovery of bioactive compounds: phenols, flavonoids, phytosterols and β-sitosterol. The extracted phytocompounds and phenolics were characterized by gas chromatography mass spectrometry (GC/MS) and ultra performance liquid chromatography (UPLC). The results showed that MAE was the best technique to achieve a high yield and a maximal total polyphenol content (11.30 ± 0.39 mg GAE/g DM) and flavonoids content (and 4.66 ± 0.20 mg GAE/g DM), whereas SFE was the best method for phytosterols and β-Sitosterol extraction. P-MAE merely enhanced the polyphenol and flavonoids yield to 14.56 ± 0.77 mg GAE/g DM and 5.29 ± 0.30 mg QE/g DM respectively, without significant variations on the type of compounds obtained. MAE appears as the most efficient technique for the extraction of phytochemical compounds from C. nutans in a short time with a reasonable yield and a good selectivity toward bioactive nutraceutical compounds, with high concentrations of antioxidants, anti-inflammatory and antimicrobial compounds.
Subcritical water extraction (SWE) is a technique based on the use of water as an extractant, at temperatures between 100 and 374 °C and at a pressure high enough to maintain the liquid state. SWE provides higher selectivities, low cost, and shorter extraction times. In this study, phenolic compounds in flaxseed (Linum usitatissimum L.) meal sticks were extracted with subcritical water using accelerated solvent extractor. For this aim, the interactions between temperature (160, 170, and 180 °C) and extraction time (5, 15, 30, and 60 min) for subcritical water extraction of SDG lignan, total phenolics, and total flavonoids from flaxseed meal sticks were investigated. The highest extraction yield of SDG lignan (77.01 %) in subcritical water extracts was determined at 160 °C for 60 min. However, high extraction yields were obtained as 70.67 and 72.57 % at 170 and 180 °C for 15 min, respectively. Also, the highest extraction yield of total phenolics (70.82 %) and total flavonoids (267.14 %) were determined at 180 °C for 15 min. Besides, high correlations between SDG lignan–total phenolics, SDG lignan–total flavonoids, and total phenolics–total flavonoids were obtained from 0.86 to 1 in water extracts.
The aim of this study was to investigate the effective parameters for subcritical water extraction of secoisolariciresinol diglucoside (SDG) lignan from flaxseed using accelerated solvent extractor. For this aim, the influence of extraction parameters such as material shape (flaxseed, ground flaxseed meal and flaxseed meal sticks), temperature (120, 140, 160 and 180 °C), extraction time (15, 30, 60 and 90 min), pressure (1.500 and 2.000 psi), fresh water (5, 40 and 100 %) and sample amount (5 and 10 g) was studied. SDG lignan analysis has been carried out by LC–MS/MS. It was shown that material shape, temperature, extraction time and sample amount had significant effect on SDG lignan content in water extracts (p < 0.05). The highest amount (12.94 mg/g) and extraction yield (72.57 %) were obtained at 180 °C for 15 min, 1.500 psi and 40 % fresh water using 5 g of flaxseed meal sticks.
Supercritical Fluid Extraction (SFE) and Subcritical Water Extraction (SWE) from mango leaves were applied in order to obtain extracts with high phenolic content and potent antioxidant activity. The effects of extraction conditions on sub- and supercritical CO2 extraction were analyzed: temperature (35 and 55 °C), pressure (10 and 40 MPa), percentage of co-solvent (0 and 20%) and type of co-solvent (methanol/ethanol). The best condition (CO2 + 20% of ethanol at 10 MPa, 55 °C, 20 g/min and 3 h) was compared with SWE (4 MPa, 100 °C, 10 g/min, and 3 h) using seven mango cultivars. SWE was more efficient than subcritical CO2 + ethanol. The antioxidant activity was evaluated by DPPH assay, and the quantification of the main polyphenols of mango leaves by HPLC analysis. SWE showed global yields up to 35% for Kent variety, and extracts with antioxidant activities superior to (+)-α-tocopherol related with their high content on the polyphenols mangiferin and quercetin.
Subcritical water (about 10MPa) is an excellent solvent for extracting non-polar flavonoids by varying the temperature-dependent dielectric constant. This study determined the optimum conditions for subcritical water extraction (SWE), such as the time and temperature, for extracting flavonoids from eight plants, and their dependence on the chemical structure of flavonoids (polarity of side chains and the presence of sugar, and double bonds). Flavonoids having an OH side chain (quercetin at 170°C/10min) were optimally extracted at lower temperatures than O-CH3 (isorhamnetin at 190°C/15min) and H (kaempferol at 190°C/15min) side chains. The optimal temperatures of the glycoside forms including sugar, such as quercitrin (110°C/5min), spiraeoside (150°C/15min), and isoquercitrin (150°C/15min), were lower than of the less-polar aglycones (170°C/10min and 190°C/15min). Apigenin, having double bonds, was extracted well at a higher temperature (190°C/15min) than naringenin (170°C/15min) in SWE.
There is a great interest in searching for new environmentally sustainable techniques to enhance the use of agricultural byproducts. In this work, a response surface methodology was used to study the influence of the two independent variables, temperature (25-200 °C) and extraction time (3-17 min) in the extraction of antioxidants by pressurized hot water extraction (PHWE) from industrial apple byproducts. The optimized extraction method for determination of flavonols was at 120 °C and 3 min, giving a predicted total yield of flavonols of 1.3 µmol/g dry apple byproduct. Results obtained suggest that new antioxidant compounds were formed at the higher extraction temperatures. A desirability function response surface considering maximum antioxidant capacity and minimal formation of brown colour, was calculated and gave an optimum of 125 °C and 3 min. This latter PHWE method correlates well with the obtained results for flavonols, thus a desirability function is a simpler alternative method for finding optimal conditions.
The effects of temperature (50 to 200 °C) and contact time (5 to 30 min) on the pressurized hot water extraction of deodorised thyme were explored for antioxidant activity, polyphenol profiles and total antioxidants. Six not previously reported polyphenolic compounds were identified in thyme. An inverse correlation was found between the antioxidant activity and total antioxidants with the amount and diversity of polyphenols. The highest total extract yield and antioxidant activity was obtained at 200 °C, although maximum polyphenol extraction yields of hydroxycinnamic acids, flavones, flavonols/flavanones and total polyphenols were detected at 100ºC and 5 min. Higher temperatures and longer exposure times reduced extract polyphenol diversity. Dihydroxyphenyllactic acid was the only phenolic compound whose extraction yield increased with temperature, probably as a product of the thermal degradation of rosmarinic acid. Consequently, for extracting phenolics from thyme 100ºC and 5 min would be appropriate operating conditions, whereas antioxidant-active non-phenolic compounds were favoured at higher temperatures and exposure times.
The increasing interest of consumers in functional foods has brought about a rise in demand for functional ingredients obtained using “natural” processes. In this review, new environmentally clean technologies for producing natural food ingredients are discussed. This work provides an updated overview on the principal applications of two clean processes, supercritical fluid extraction and subcritical water extraction, used to isolate natural products from different raw materials, such as plants, food by-products, algae and microalgae. Although the extraction of some compounds with antibacterial, antiviral or antifungical activity is discussed, special attention is paid to the extraction of antioxidant compounds, due to their important role in food preservation and health promotion.
Scavenging of DPPH free radical is the basis of a common antioxidant assay. A number of protocols have been followed for this assay resulting in variation in the results of different laboratories. We present a perspective of the protocols followed by different workers with incongruity in their results and recommend a standard procedure within the sensitivity range of spectrophotometry. Three common standard antioxidants viz. ascorbic acid, BHT and propyl gallate have been used in this study. The IC50 values for ascorbic acid and propyl gallate were 11.8 μM and 4.4 μM in methanol and 11.5 μM and 4.7 μM in buffered methanol as reaction medium, respectively. The free radical scavenging by BHT was markedly influenced by the reaction medium. The IC50 values were 60.0 μM and 9.7 μM when the reaction was done in methanol and buffered methanol, respectively.
A review is presented of recent extraction techniques for solid matrices, covering: principles and optimization of SFE, pressurized-fluid extraction and microwave extraction; comparison of SFE, pressurized-fluid extraction and microwave extraction with regard to efficiency, susceptibility to matrix effects, selectivity, automation, and simplicity of operation; technique selection for different applications; and future trends. (90 references).
Colorectal carcinoma is a leading cause of human mortality due to its high metastatic ability. Because the activation of matrix metalloproteinases (MMP) is a key factor in the metastatic process, agents with the ability to inhibit MMP activity have potential in the treatment of colorectal carcinoma. In the present study, among 36 flavonoids examined, myricetin was found to be the most potent inhibitor of MMP-2 enzyme activity in COLO 205 cells (IC50 = 7.82 micromol/L). Myricetin inhibition of MMP-2 enzyme activity was also found in the human colorectal carcinoma cell lines COLO 320HSR, COLO 320DM, HT 29, and COLO 205-X (IC50 = 11.18, 11.56, 13.25, and 23.51 micromol/L, respectively). In contrast, no inhibitory effect of MMP-2 protein expression or enzyme activity was observed in myricitrin (myricetin-3-rhamnoside)-treated cells. In 12-O-tetradecanoylphorbol-13-acetate (TPA)-stimulated COLO 205 cells, an increase in MMP-2 protein expression and enzyme activity, as well as of protein kinase C (PKC) alpha protein translocation, extracellular signal-regulated kinase (ERK) 1/2 protein phosphorylation, and c-Jun protein expression was observed. ERK inhibitor (PD98059) and PKC inhibitors (GF-109203X and H-7), but not p38 inhibitor (SB203580) or c-jun-NH2-kinase inhibitor (SP600125), significantly inhibited TPA-induced MMP-2 protein expression, with reduced ERK phosphorylation and c-Jun protein expression. Addition of myricetin but not myricitrin suppressed TPA-induced MMP-2 protein expression in COLO 205 cells by blocking the TPA-induced events, including translocation of PKCalpha from cytosol to membrane, phosphorylation of ERK1/2 protein, and induction of c-Jun protein expression. Addition of PD98059 or GF-109203X significantly enhanced the inhibitory effect of myricetin on MMP-2 enzyme activity induced by TPA. Furthermore, myricetin, but not myricitrin, suppressed TPA-induced invasion of COLO 205 cells in an in vitro invasion assay using Engelbreth-Holm-Swarm sarcoma tumor extract Matrigel-coated Transwells. Results of the present study indicate that myricetin significantly blocked both endogenous and TPA-induced MMP-2 enzyme activity by inhibiting its protein expression and enzyme activity. The blockade involved suppression of PKC translocation, ERK phosphorylation, and c-Jun protein expression.
In the present work, oregano leaves (Origanum vulgare L.) are explored as natural source of nutraceuticals with antioxidant activity. To do this, subcritical water extraction (SWE), a new environmentally friendly technique, is employed as extraction procedure and HPLC coupled to DAD is used for the chemical characterization of the extracts. Moreover, the radical scavenging 1,1-diphenyl-2-picrylhydrazyl (DPPH) method and the determination of the total phenolic content (measured with the Folin test) are applied to evaluate the antioxidant activity of the extracts. The extraction of antioxidants from oregano leaves by SWE is studied considering different temperatures (25, 50, 100, 150 and 200 degrees C) to investigate the selectivity of the process. The highest antioxidant activity is observed for the extract obtained at the highest temperature, 200 degrees C (EC(50) equal to 10 microg/ml). Moreover, the extraction yield was also the highest (54% dry weight) at these extraction conditions. The total phenolic content showed no differences among the different extracts, concluding that the amount of phenolic compounds extracted was similar but the type and structure of the phenolics was different, providing in this way different antioxidant activity. Some compounds could be tentatively identified, proposing some probable chemical structures for some of them, such as flavanones, dihydroflavonols, favonols and flavones.
Pressurized liquid extraction (PLE) using water and a 70:30 mixture of ethanol and water over the temperature range of 50 to 190 degrees C was used to extract flavonoids from dried spinach. The total phenolic content, antioxidant capacity, color, and browning indices of the extracts were also evaluated. PLE using a 70:30 mixture of ethanol and water was more effective than water in extracting flavonoids from spinach. Flavonoids were effectively extracted over the temperature band of 50 to 130 degrees C with water and 50 to 150 degrees C with ethanolic solvent. Levels of total phenolics and ORAC values increased with increasing extraction temperature, indicating that flavonoids were minor contributors to antioxidant capacity at elevated extraction temperatures. Browning of ethanolic extracts correlated highly with ORAC values over the temperature range of 50 to 190 degrees C, and the ORAC values of the large molecular weight fraction (> 1000 Da) increased linearly over the temperature range, indicating that Maillard polymers were the major contributors to antioxidant capacity. The results illustrate that PLE temperatures of < 130 degrees C for water or < 150 degrees C for ethanolic solvent may be used to extract flavonoids, followed by a high temperature (> 170 degrees C) extraction to generate antioxidant-rich moieties.
Leafy Medicinal Herbs: Botany, Chemistry, Postharvest Technology and Uses
- D C P Ambrose
- A Manickavasagan
- R Naik
Ambrose, D.C.P., A. Manickavasagan and R. Naik, 2016. Leafy Medicinal Herbs: Botany, Chemistry,
Postharvest Technology and Uses. Central Institute of Agricultural Engineering (ICAR) Publisher: 10-12.
Extraction of antioxidants from leaves of Clin a ca n thu s nutans: Effect of extraction method and solvent
- N S Karim
Karim, N.S, and Muhamad, 2015. Extraction of antioxidants from leaves of Clin a ca n thu s nutans:
Effect of extraction method and solvent. In the proceeding of Herbs Industry, 192-194.
Chemical and functional characterization Optimization and economic evaluation of pressurized liquid extraction of phenolic compounds from jabuticaba skins
Subcritical water extraction of nutraceuticals with antioxidant activity from oregano. Chemical and
functional characterization. Journal of Pharmaceutical and Biomedical Analysis, 41(5): 1560-1565.
Santos, D.T., P.C. Veggi and M.A.A. Meireles, 2012. Optimization and economic evaluation of
pressurized liquid extraction of phenolic compounds from jabuticaba skins. Journal of Food
Engineering, 108(3): 444-452.
Antioxidant and Wound Healing Activity of Polyherbal Fractions of Clinacanthus nutans and Elephantopus scaber
- D C P Ambrose
- A Manickavasagan
- R Naik
Ambrose, D.C.P., A. Manickavasagan and R. Naik, 2016. Leafy Medicinal Herbs: Botany, Chemistry,
Postharvest Technology and Uses. Central Institute of Agricultural Engineering (ICAR) Publisher: 10-12.
Aslam, M.S., M.S. Ahmad, A.S. Mamat, M.Z. Ahmad and F. Salam, 2016. Antioxidant and Wound
Healing Activity of Polyherbal Fractions of Clinacanthus nutans and Elephantopus scaber. Evidence-Based
Complementary and Alternative Medicine, 2(14): 2-14.
UniKL RCMP FPHS, and Jhuma Deb. Pharmacognostical Studies On Stem Bark Of Acacia Ferruginea DC
- D Kumar
- Ghouri
Kumar, D., Ghouri, 2014. UniKL RCMP FPHS, and Jhuma Deb. Pharmacognostical Studies On Stem Bark
Of Acacia Ferruginea DC.
Phytochemicals and Antioxidant Capacities from Dacryodes rostrata Fruits
- L H Tee
- R N Ramanan
- B T Tey
- E S Chan
- A Azrina
- I Amin
- Y Bao
- C Y Lau
- K N Prasad
Tee, L.H., R.N. Ramanan, B.T. Tey, E.S. Chan, A. Azrina, I. Amin, Y. Bao, C.Y. Lau and K.N. Prasad,
2105. Phytochemicals and Antioxidant Capacities from Dacryodes rostrata Fruits. Medicinal Chemistry, 5(1):
23-27.