Separation of the main flavonoids and essential oil from seabuckthorn leaves by ultrasonic/microwave-assisted simultaneous distillation extraction

Recent advances in methods of extraction, pre-concentration, purification, identification, and quantification of kaempferol

As a naturally widely-occurring dietary, cosmetic, and therapeutic flavonoid, kaempferol has gained much consideration for its nutritional and pharmaceutical properties in recent years. Although there have been performed a high number of studies associated with different aspects of kaempferol's analytical investigations, the lack of a comprehensive summary of the various methods and other plant sources that have been reported for this compound is being felt, especially for many biological applications. This study, aimed to provide a detailed compilation consisting of sources (plant species) and analytical information that was precisely related to the natural flavonoid (kaempferol). There is a trend in analytical research that supports the application of modern eco-friendly instruments and methods. In conclusion, ultrasound-assisted extraction (UAE) is the most general advanced method used widely today for the extraction of kaempferol. During recent years, there is an increasing tendency towards the identification of kaempferol by different methods.

Recent advances in the implementation of ultrasound technology for the extraction of essential oils from terrestrial plant materials: A comprehensive review

Ultrasound-assisted extraction (UAE) is an innovative process for recovering valuable substances and compounds from plants and various biomaterials. This technology holds promise for resource recovery while maintaining the quality of the extracted products. The review comprehensively discusses UAE's mechanism, applications, advantages, and limitations, focusing on extracting essential oils (EOs) from diverse terrestrial plant materials. These oils exhibit preservation, flavor enhancement, antimicrobial action, antioxidant effects, and anti-inflammatory benefits due to the diverse range of specific compounds in their composition. Conventional extraction techniques have been traditionally employed, and their limitations have prompted the introduction of novel extraction methods. Therefore, the review emphasizes that the use of UAE, alone or in combination with other cutting-edge technologies, can enhance the extraction of EOs. By promoting resource recovery, reduced energy consumption, and minimal solvent use, UAE paves the way for a more sustainable approach to harnessing the valuable properties of EOs. With its diverse applications in food, pharmaceuticals, and other industries, further research into UAE and its synergies with other cutting-edge technologies is required to unlock its full potential in sustainable resource recovery and product quality preservation.

Determination of cinnamaldehyde, thymol and eugenol in essential oils by LC-MS/MS and antibacterial activity of them against bacteria

Plant essential oils contain many secondary metabolites, some of which can effectively inhibit the growth of pathogenic microorganisms, so it is a very promising antibacterial agent. In this study, a qualitative and quantitative method based on high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed for the simultaneous determination of three bioactive substances, cinnamaldehyde (CNM), thymol (THY), and eugenol (EUG), in the essential oils of plants. Necessary tests for linearity, limit of quantification, recovery, carryover contamination and precision of the method were carried out. Then, the antibacterial activity of 3 bioactive compounds against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was evaluated by minimal inhibitory concentration and the synergistic antimicrobial effect. The results indicated that CNM, THY and EUG had good antibacterial activity. According to the results of fractional inhibitory concentration index (FICI), it is considered that CNM + THY and CNM + THY + EUG has obvious synergistic inhibitory effect on E. coli, and CNM + THY and CNM + EUG has obvious synergistic inhibitory effect on S. aureus. Finally, we analyzed the effect of the bioactive compounds on trace elements in bacteria and found significant changes in magnesium, calcium, copper and iron.

Flavonoids from Seabuckthorn (Hippophae rhamnoides L.) mimic neurotrophic functions in inducing neurite outgrowth in cultured neurons: Signaling via PI3K/Akt and ERK pathways

BACKGROUND

Various brain disorders, including neurodegenerative diseases and major depressive disorders, threaten an increasing number of patients. Seabuckthorn, a fruit from Hippophae rhamnoides L., is an example of "medicine food homology". The fruit has enriched flavonoids that reported to have benefits in treating cognitive disorders. However, the studies on potential functions of Seabuckthorn and/or its flavonoid-enriched fraction in treating neurodegenerative disorders are limited.

PURPOSE

This study aimed to determine the ability and mechanism of the flavonoid-enriched fraction of Seabuckthorn (named as SBF) in mimicking the neurotrophic functions in inducing neurite outgrowth of cultured neurons.

METHODS

Cultured PC12 cell line, SH-SY5Y cell line and primary neurons (cortical and hippocampal neurons isolated from E17-19 SD rat embryos) were the employed models to evaluate SBF in inducing neurite outgrowth by comparing to the effects of NGF and BDNF. Immuno-fluorescence staining was applied to identify the morphological change during the neuronal differentiation. Luciferase assay was utilized for analyzing the transcriptional regulation of neurofilaments and cAMP/CREB-mediated gene. Western blot assay was conducted to demonstrate the expressions of neurofilaments and phosphorylated proteins.

RESULTS

The application of SBF induced neuronal cell differentiation, and this differentiating activation was blocked by the inhibitors of PI3K/Akt and ERK pathways. Additionally, SBF showed synergy with neurotrophic factors in stimulating the neurite outgrowth of cultured neurons. Moreover, the major flavonoids within SBF, i.e., isorhamnetin, quercetin and kaempferol, could account for the neurotrophic activities of SBF.

CONCLUSION

Seabuckthorn flavonoids mimicked neurotrophic functions in inducing neuronal cell differentiation via activating PI3K/Akt and ERK pathways. The results suggest the beneficial functions of Seabuckthorn as a potential health food supplement in treating various brain disorders, e.g., neurodegenerative diseases.

A Comprehensive Review on Extraction, Structure, Detection, Bioactivity, and Metabolism of Flavonoids from Sea Buckthorn (Hippophae rhamnoides L.)

Sea buckthorn (Hippophae rhamnoides L.) is an important plant with homology of medicine and food. It has rich nutritional and medicinal properties. It is used as a traditional Chinese medicine with therapeutic functions of invigorating spleen, relieving cough, eliminating food, eliminating phlegm, dispersing blood stasis, and promoting blood circulation. This review comprehensively summarized flavonoids from sea buckthorn (Hippophae rhamnoides L.), including extraction methods (solvent extraction, ultrasound-assisted extraction, microwave-assisted extraction, enzyme-assisted extraction, and collaborative extraction), two structure types (18 flavone aglycones and 81 flavone glycosides), detection methods (UV, HPLC, and NMR), bioactivities (antiviral, anti-inflammatory, hepatoprotective, weight-reducing, and hypoglycemic activities), and physiological metabolisms (most of flavonoids are converted into small molecule monophenolic acids through intestinal microbial catabolism). It will supply an important theoretical basis and valuable reference for researching and exploiting sea buckthorn (Hippophae rhamnoides L.) in the future. Practical Applications. Sea buckthorn (Hippophae rhamnoides L.) is an edible and medical plant with many functional properties. A comprehensive review on extraction, structure, detection, bioactivity, and metabolism of flavonoids from sea buckthorn (Hippophae rhamnoides L.) was made in this paper. This review will provide an important foundation for further studies of sea buckthorn (Hippophae rhamnoides L.) focusing on its development and utilization.

Extraction of curcumin from turmeric by ultrasonic-assisted extraction, identification, and evaluation of the biological activity

Introduction: Dried rhizomes of turmeric have been traditionally used as a medicinal herb, dietary spice, food source, food preservative, and natural coloring agent in many Asian countries. This study aimed to develop the ultrasonic-assisted extraction (UAE) method for the extraction of curcumin from turmeric powder, evaluate the extraction efficiency, curcumin concentration, and biological activities.Methods: The UAE effects were examined based on several parameters of extraction efficiencies. The curcumin content was also determined using high-performance liquid chromatography (HPLC), and the total phenolic content (TPC) was estimated by Folin-Ciocalteu colorimetric method. The antibacterial activity of the extracted was evaluated against the test pathogenic bacteria by the disc diffusion method. The correlation between extraction yield and curcumin content was performed by principal components analysis (PCA).Results: The optimal UAE conditions were: ethanol, a solid-liquid ratio of 1:10 (w/v), an extraction time of 40 min, and only one extraction step. Under the optimal conditions, the yield of curcumin was 160.3 ± 1.17 (mg/g extract) and the TPC was 185.5 ± 3.07 (mg gallic acid equivalent /g extract). PCA presented the positive correlation between curcumin and the TPC of the studied extracts. Comparison of antibacterial activity between UAE and maceration method against the tested bacteria showed no significant difference at P > 0.05.Conclusion: UAE was a viable alternative as a rapid, efficient, and simple means of extraction of curcumin from turmeric. The extracts had great potential as a source of antioxidant agents with high amounts of curcuminoids, phenolic compounds and exhibited activity against pathogenic bacteria.

Selective separation of main flavonoids by combinational use of ionic liquid-loaded microcapsules from crude extract of Tartary buckwheat

For selective adsorption of main flavonoids from crude Tartary buckwheat extract (rutin, 0.021 mg/mL; quercetin, 0.030 mg/mL; and kaempferol, 0.011 mg/mL), new ionic liquid-based sorbents were successfully prepared by encapsulating [Bmim]Br and [Bmim]Pro in regular spherical non-magnetic and magnetic microcapsules with polysulfone content of 8%, respectively. After appropriate loading process, the microcapsules were comprehensively characterized by infrared spectroscopy, thermogravimetry analysis and scanning electron microscopy. Then the separation strategy was designed to separate rutin and quercetin from kaempferol by combinational use of two kinds of IL-loaded microcapsules (ILLMs). The effects of solid-liquid ratio of ILLMs and extract, pH, time and adsorption temperature were all investigated. The experimental data fit well with the quasi-second-order kinetics model and Langmuir model. After desorption, target flavonoids were well recovered and the ILLMs showed good stability. As the result, a new IL-based separation technology for main flavonoids from food crop was developed for the first time.

Evaluation of Structurally Different Ionic Liquid-Based Surfactants in a Green Microwave-Assisted Extraction for the Flavonoids Profile Determination of Mangifera sp. and Passiflora sp. Leaves from Canary Islands

Aqueous solutions of ionic liquids (ILs) with surface active properties were used as extraction solvents, taking advantage of their impressive solvation properties, in a green microwave-assisted solid-liquid extraction method (IL-MA-SLE) for the extraction of flavonoids from passion fruit and mango leaves. The extraction method was combined with high-performance liquid chromatography and photodiode-array detection (HPLC-PDA) and optimized by response surface methodology using the Box-Behnken experimental design. Under optimum conditions, the extraction efficiency of six structurally different IL-based surfactants was evaluated. Thus, imidazolium-, guanidinium- and pyridinium-type ILs with different tailorable characteristics, such as side chain length and multicationic core, were assessed. The decylguanidinium chloride ([C10Gu+][Cl-]) IL-based surfactant was selected as key material given its superior performance and its low cytotoxicity, for the determination of flavonoids of several samples of Passiflora sp. and Mangifera sp. leaves from the Canary Islands, and using as target analytes: rutin, quercetin and apigenin. The analysis of 50 mg of plant material only required 525 µL of the low cytotoxic IL-based surfactant solution at 930 mM, 10.5 min of microwave irradiation at 30 °C and 50 W, which involves a simpler, faster, more efficient and greener method in comparison with other strategies reported in the literature for obtaining bioactive compounds profiles from plants.

Ameliorative effects of sea buckthorn oil on DNCB induced atopic dermatitis model mice via regulation the balance of Th1/Th2

BACKGROUND

Atopic dermatitis (AD) is a worldwide chronic skin disease which burden public health. Sea buckthorn (SBT) (Hippophae rhamnoides L., Elaeagnaceae) oil, as a traditional herbal medicine, has been used for disease treatment for many years. The effects of SBT oil on AD mouse model induced by repeated administration of 2,4-dinitrochlorobenzene (DNCB) in BALB/c mice was evaluated in this study.

METHODS

Mice were divided into four groups including the normal control group, AD model group, AD model group treated with SBT oil (5 ml/kg) and AD model group treated with SBT oil (10 ml/kg). Same volume at different concentrations of SBT oil was applied daily on the latter two groups by gavage for 15 days following AD model induction. The function of skin barrier and the production of IL-4, IFN-γ, TNF-α and TSLP were examined after animal sacrifice. The migration and mature of langerhans cell (LCs) in lymph node was further assessed by flow cytometry.

RESULTS

SBT oil alleviated dermatitis scores, decreased ear thickness, prevented infiltration of mast cell, reduced lymph node weight and depressed activity of Th2 cells. SBT oil also reduced the expression of IL-4, IFN-γ, TNF-α and TSLP in ear tissue, IgE level in serum and mRNA relative expression of IL-4, IFN-γ, TNF-α in lymph node. Moreover, SBT oil inhibited the migration of LCs cells from local lesions to lymph node and it's mature in lymph node.

CONCLUSIONS

These results suggest SBT oil had a beneficial effect either systemic or regional on DNCB-induced AD mice via maintain the balance of Th1/Th2 and may be a potential complementary candidate for AD treatment.

Hydrothermal Carbonization and Pellet Production from Egeria densa and Lemna minor

Biofuels are seen as a potential option for mitigating the effects of fossil fuel use. On the other hand, nutrient pollution is accelerating eutrophication rates in rivers, lakes, and coastal waters. Harvesting aquatic plants to produce biofuels could mitigate this problem, though it is important to attack the problem at source, mainly as regards the contribution of nutrients. For the first time, solid biofuels were obtained in the forms of carbon and pellets from the aquatic plants Egeria densa, which is classed as an invasive plant under the Spanish Catalogue of Exotic Invasive Species, and Lemna minor, both of which can be found in the Umia River in north-west Spain. The essential oils and macro- and microelements present in both these plants were also extracted and analyzed. The higher heating values (HHVs) of the carbon products obtained ranged from 14.28 to 17.25 MJ/kg. The ash content ranged from 22.69% to 49.57%. The maximum yield obtained for biochar for Egeria densa at 200 °C was 66.89%. Temperature significantly affects solid hydrochar yield. The HHVs of the pellets obtained ranged from 11.38 to 13.49 MJ/kg. The use of these species to obtain biofuels through hydrothermal carbonization (HTC) and pellets is a novel and effective approach that will facilitate the removal of nutrients that cause eutrophication in the Umia River. The elements extracted show that harvesting these plants will help to remove excessive nutrients from the ecosystem.

New developments on ultrasound-assisted processing and flavor detection of spices: A review

Spices are widely used to add unique flavors to food; such uniqueness may, however, suffer significant loss during processing, which is in many cases needed to preserve or transform spices into food ingredients. Here, the effects of ultrasound-assisted drying, extraction and microencapsulation on flavor of spices along with selected progresses made on ultrasonic detection of the flavor are reviewed. Flavors of some spices, e.g., laurel, onion and peppermint, dried with the aid of ultrasound are noted to be better than those of shade-dried, infrared, microwave and hot-air dried products. Ultrasound-assisted extraction can be effectively used to extract essential oils or oleoresins from spices. Compared with selected extraction methods, the variety of flavor substances obtained via ultrasound-assisted extraction is richer and their concentrations are also higher, making the flavors of the extracts stronger. Ultrasound-assisted microencapsulation has noted to increase the compound embedding and loading ratios, resulting in better maintenance of flavor over a longer period of time. Ultrasound has finally proved to be an efficient, green, economical and sensitive flavor detection technology for spices.

Thermodynamic, structural and dynamic properties of ionic liquids [C4mim][CF3COO], [C4mim][Br] in the condensed phase, using molecular simulations

In this work a series of thermodynamic, structural, and dynamical properties for the 1-butyl-3-methylimidazolium trifluoroacetate ([C4mim][CF3COO]) and 1-butyl-3-methylimidazolium bromide, ([C4mim][Br]) ionic liquids (ILs) were calculated using Non-polarizable Force Fields (FF), parameterized using a methodology developed previously within the research group, for condensed phase applications. Properties such as the Vapor-Liquid Equilibrium (VLE) curve, critical points (ρ c, T c), Radial, Spatial and Combined Distribution Functions and self-diffusion coefficients were calculated using Equilibrium Molecular Dynamics simulations (EMD); other properties such as shear viscosities and thermal conductivities were calculated using Non-Equilibrium Molecular Dynamics simulations (NEMD). The results obtained in this work indicated that the calculated critical points are comparable with those available in the literature. The calculated structural information for these two ILs indicated that the anions interact mainly with hydrogen atoms from both the imidazolium ring and the methyl chain; the bromide anion displays twice the hydrogen coordination number than the oxygen atoms from the trifluoroacetate anion. Furthermore, Non-Covalent interactions (NCI index), determined by DFT calculations, revealed that some hydrogen bonds in the [C4mim][Br] IL displayed similar strength to those in the [C4mim][CF3COO] IL, in spite of the shorter O--H distances found in the latter IL. The majority of the calculated transport properties presented reasonable agreement with the experimental available data. Nonetheless, the self-diffusion coefficients determined in this work are under-estimated with respect to experimental values; however, by escalating the electrostatic atomic charges for the anion and cation to ±0.8e, only for this property, a remarkable improvement was obtained. Experimental evidence was recovered for most of the calculated properties and to the best of our knowledge, some new predictions were done mainly in thermodynamic states where data are not available. To validate the FF, developed previously within the research group, dynamic properties were also evaluated for a series of ILs such as [C4mim][PF6], [C4mim][BF4], [C4mim][OMs], and [C4mim][NTf2] ILs.

Coupling Ultrasound with Heat-Reflux to Improve the Extraction of Quercetin, Kaempferol, Ginkgetin and Sciadopitysin from Mairei Yew Leaves

The coupling of ultrasound and heat–reflux extraction (UHRE) was developed for separation for quercetin (QU), kaempferol (KA), ginkgetin (GI) and sciadopitysin (SC) from Mairei Yew leaves. The Box–Behnken design was used to optimize the UHRE conditions for obtaining the maximum yield of flavonoids. The optimal extraction conditions were as follows: boiling 80% methanol (V/V) for extraction solvent, 20 min for the extraction time, 200 W for the ultrasonic power and 26 mL/g for the liquid–solid ratio. By UHRE, the yields of QU, KA, GI and SC were, respectively, 0.109, 0.406, 0.031 and 0.355 mg/g, and total yield of four flavonoids was 0.901 mg/g, which were, respectively, 1.25-fold and 1.23-fold higher than those by using ultrasonic-assisted extraction (UAE) and heating reflux extraction (HRE). Moreover, the extraction time for the equilibrium yields of flavonoids using UHRE was 83.3% and 27.8%, respectively, less than the corresponding time using UAE and HRE. Compared with HRE and UAE, UHRE showed the increase of cell disruption degree as observed by scanning electron microscopy, which may be the reason for high yield and rapid extraction of target compounds.