Green and Efficient Extraction of Phenolic Components from Plants with Supramolecular Solvents: Experimental and Theoretical Studies.

The supramolecular solvent (SUPRAS) has garnered significant attention as an innovative, efficient, and environmentally friendly solvent for the effective extraction and separation of bioactive compounds from natural resources. However, research on the use of a SUPRAS for the extraction of phenolic compounds from plants, which are highly valued in food products due to their exceptional antioxidant properties, remains scarce. The present study developed a green, ultra-sound-assisted SUPRAS method for the simultaneous determination of three phenolic acids in Prunella vulgaris using high-performance liquid chromatography (HPLC). The experimental parameters were meticulously optimized. The efficiency and antioxidant properties of the phenolic compounds obtained using different extraction methods were also compared. Under optimal conditions, the extraction efficiency of the SUPRAS, prepared with octanoic acid reverse micelles dispersed in ethanol-water, significantly exceeded that of conventional organic solvents. Moreover, the SUPRAS method demonstrated greater antioxidant capacity. Confocal laser scanning microscopy (CLSM) images revealed the spherical droplet structure of the SUPRAS, characterized by a well-defined circular fluorescence position, which coincided with the position of the phenolic acids. The phenolic acids were encapsulated within the SUPRAS droplets, indicating their efficient extraction capacity. Furthermore, molecular dynamics simulations combined with CLSM supported the proposed method's mechanism and theoretically demonstrated the superior extraction performance of the SUPRAS. In contrast to conventional methods, the higher extraction efficiency of the SUPRAS can be attributed to the larger solvent contact surface area, the formation of more types of hydrogen bonds between the extractants and the supramolecular solvents, and stronger, more stable interaction forces. The results of the theoretical studies corroborate the experimental outcomes.

Ultrasonic-Assisted Extraction of Xanthorrhizol from Curcuma xanthorrhiza Roxb. Rhizomes by Natural Deep Eutectic Solvents: Optimization, Antioxidant Activity, and Toxicity Profiles.

Xanthorrhizol, an important marker of Curcuma xanthorrhiza, has been recognized for its different pharmacological activities. A green strategy for selective xanthorrhizol extraction is required. Herein, natural deep eutectic solvents (NADESs) based on glucose and organic acids (lactic acid, malic acid, and citric acid) were screened for the extraction of xanthorrhizol from Curcuma xanthorrhiza. Ultrasound-assisted extraction using glucose/lactic acid (1:3) (GluLA) gave the best yield of xanthorrhizol. The response surface methodology with a Box-Behnken Design was used to optimize the interacting variables of water content, solid-to-liquid (S/L) ratio, and extraction to optimize the extraction. The optimum conditions of 30% water content in GluLA, 1/15 g/mL (S/L), and a 20 min extraction time yielded selective xanthorrhizol extraction (17.62 mg/g) over curcuminoids (6.64 mg/g). This study indicates the protective effect of GluLA and GluLA extracts against oxidation-induced DNA damage, which was comparable with those obtained for ethanol extract. In addition, the stability of the xanthorrhizol extract over 90 days was revealed when stored at -20 and 4 °C. The FTIR and NMR spectra confirmed the hydrogen bond formation in GluLA. Our study reported, for the first time, the feasibility of using glucose/lactic acid (1:3, 30% water v/v) for the sustainable extraction of xanthorrhizol.

Effect of employing different extraction techniques and solvents on the total phenolic content and antioxidant properties of an Iranian endemic species Zeravschania khorasanica (Apiaceae).

Zeravschania khorasanica, a species endemic to the eastern part of Iran, possesses distinct characteristics that distinguish it from its two closely related species. This research employed five different extraction techniques to identify the active components, total phenolic content and in vitro antioxidant activity of the extract. Furthermore, hydro-distillation was utilized for GC/MS analysis to determine the composition of the essential oil. The total phenolic content was estimated using the Folin-Ciocalteu assay and the antioxidant capacity was evaluated using the DPPH radical scavenging test. The findings revealed that ethanolic Soxhlet extraction yielded the highest efficiency in extracting total phenolic content (88.19 ±1.99 gallic acid mg/100g). In contrast, water maceration extraction demonstrated the highest antioxidant activity (68.1 ±5.4%). Interestingly, the study uncovered that there is no significant positive correlation between the phenolic content and the antioxidant activity of the plant. Additionally, HPLC analysis identified three phenolic constituents in the extract. The Soxhlet extraction method yielded the highest levels of chlorogenic acid (5.8 ppm), caffeic acid (4.1 ppm) and salicylic acid (10.3 ppm). As per the GC/MS analysis, a total of eleven compounds were identified. The predominant compounds were elemicin at 58.19% and trans--bergamotene at 25.78%.

A comparative study of sequential and simultaneous enzymatic and ultrasound-assisted aqueous two-phase extraction for anticholesterol compounds from Strobilanthes crispus leaves.

An innovative ultrasonic-assisted enzymatic aqueous two-phase extraction (UAE-ATPE) method was applied to enhance the yield from Strobilanthes crispus leaves, exploring both sequential and simultaneous approaches. Comparative analysis included assessing total phenolic content (TPC), total flavonoid content (TFC), partition coefficient (k) and recovery (R). Liquid chromatography-mass spectrometry and scanning electron microscopy evaluated extracts from both techniques. Simultaneous UAE-ATPE demonstrated significantly higher TPC (5.7±0.1 mg GAE/g dry leaves) and TFC (3.3±0.1 mg QE/g dry leaves) compared to sequential extraction, where TPC and TFC measured 4.5±0.3 mg GAE/g dry leaves and 1.7±0.1 mg QE/g dry leaves. Additionally, simultaneous UAE-ATPE yielded higher k and R values for phenolic and flavonoid compounds. Notably, it identified 32.4% of the area corresponding to 6 compounds, surpassing the 25.3% area identified sequentially with 13 compounds. A collaborative effect of enzymatic hydrolysis and ultrasonic extraction was observed in simultaneous UAE-ATPE. In the inhibition test on the HMG-CoA reductase enzyme, simultaneous UAE-ATPE extract (200 µg/mL) exhibited exceptional results, achieving superior inhibition of 66.1% compared to the sequential method's inhibition of 39.4%. This underscores the efficacy of simultaneous UAE-ATPE in producing concentrated anti-cholesterol compounds. The study strongly emphasizes the superiority of simultaneous UAE-ATPE over the sequential approach.

Unveiling the tyrosinase inhibitory potential of phenolics from Centaurium spicatum: Bridging in silico and in vitro perspectives.

Phenolics, abundant in plants, constitute a significant portion of phytoconstituents consumed in the human diet. The phytochemical screening of the aerial parts of Centaurium spicatum led to the isolation of five phenolics. The anti-tyrosinase activities of the isolated compounds were assessed through a combination of in vitro experiments and multiple in silico approaches. Docking and molecular dynamics (MD) simulation techniques were utilized to figure out the binding interactions of the isolated phytochemicals with tyrosinase. The findings from molecular docking analysis revealed that the isolated phenolics were able to bind effectively to tyrosinase and potentially inhibit substrate binding, consequently diminishing the catalytic activity of tyrosinase. Among isolated compounds, cichoric acid displayed the lowest binding energy and the highest extent of polar interactions with the target enzyme. Analysis of MD simulation trajectories indicated that equilibrium was reached within 30 ns for all complexes of tyrosinase with the isolated phenolics. Among the five ligands studied, cichoric acid exhibited the lowest interaction energies, rendering its complex with tyrosinase the most stable. Considering these collective findings, cichoric acid emerges as a promising candidate for the design and development of a potential tyrosinase inhibitor. Furthermore, the in vitro anti-tyrosinase activity assay unveiled significant variations among the isolated compounds. Notably, cichoric acid exhibited the most potent inhibitory effect, as evidenced by the lowest IC50 value (7.92 ± 1.32 µg/ml), followed by isorhamnetin and gentiopicrin. In contrast, sinapic acid demonstrated the least inhibitory activity against tyrosinase, with the highest IC50 value. Moreover, cichoric acid exhibited a mixed inhibition mode against the hydrolysis of l-DOPA catalyzed by tyrosinase, with Ki value of 1.64. Remarkably, these experimental findings align well with the outcomes of docking and MD simulations, underscoring the consistency and reliability of our computational predictions with the actual inhibitory potential observed in vitro.

Potential application of green extracts rich in phenolics for innovative functional foods: natural deep eutectic solvents as media for isolation of biocompounds from berries.

The health-promoting effects of berries have attracted attention due to the possible application of their extracts as functional ingredients in food products. Natural deep eutectic solvents (NADESs) are a new generation of environmentally friendly solvents for the extraction of natural products, and they are green alternatives to organic solvents, and they can improve the solubility, stability, and bioavailability of isolated biocompounds. In this study, an efficient eco-friendly method was used for the extraction of phenolic compounds from different berries: chokeberries, blueberries, and black goji berries with a range of eutectic solvents consisting of hydrogen bond acceptors (HBAs) such as choline chloride, L-proline, L-glycine, and L-lysine and hydrogen bond donors (HBDs) such as malic, citric, tartaric, lactic and succinic acids, glucose and glycerol. The obtained results indicated the ability of NADESs towards selective extraction of phenolics; the eutectic system choline chloride : malic acid showed selective extraction of anthocyanins, while choline chloride : glycerol and choline chloride : urea showed selectivity towards flavonoids and phenolic acids. The methodology for screening of the NADES extraction performance, which included chromatographic profiling via high-performance thin layer chromatography combined with chemometrics and spectrophotometric essays, allowed effective assessment of optimal eutectic solvents for isolation of different groups of phenolics. Great antioxidant and antimicrobial activities of extracts, along with the green nature of eutectic solvents, enable NADES berry extracts to be used as "green-labelled" functional foods or ingredients.

Differences in physicochemical properties of pectin extracted from pomelo peel with different extraction techniques.

In order to obtain high yield pomelo peel pectin with better physicochemical properties, four pectin extraction methods, including hot acid extraction (HAE), microwave-assisted extraction (MAE), ultrasound-assisted extraction, and enzymatic assisted extraction (EAE) were compared. MAE led to the highest pectin yield (20.43%), and the lowest pectin recovery was found for EAE (11.94%). The physicochemical properties of pomelo peel pectin obtained by different methods were also significantly different. Pectin samples obtained by MAE had the highest methoxyl content (8.35%), galacturonic acid content (71.36%), and showed a higher apparent viscosity, thermal and emulsion stability. The pectin extracted by EAE showed the highest total phenolic content (12.86%) and lowest particle size (843.69 nm), showing higher DPPH and ABTS scavenging activities than other extract methods. The pectin extracted by HAE had the highest particle size (966.12 nm) and degree of esterification (55.67%). However, Fourier-transform infrared spectroscopy showed that no significant difference occurred among the different methods in the chemical structure of the extracted pectin. This study provides a theoretical basis for the industrial production of pomelo peel pectin.

Effect of Post-Extraction Ultrasonication on Compositional Features and Antioxidant Activities of Enzymatic/Alkaline Extracts of Palmaria palmata.

Palmaria palmata is a viable source of nutrients with bioactive properties. The present study determined the potential role of post-extraction ultrasonication on some compositional features and antioxidant properties of enzymatic/alkaline extracts of P. palmata (EAEP). No significant difference was detected in terms of protein content and recovery, as well as the amino acid composition of the extracts. The nitrogen-to-protein conversion factor of 5 was found to be too high for the seaweed and EAEP. The extracts sonicated by bath for 10 min and not sonicated showed the highest and lowest total phenolic contents (p < 0.05), respectively. The highest radical scavenging and lowest metal-chelating activities were observed for the non-sonicated sample, as evidenced by IC50 values. The extract sonicated by bath for 10 min showed the most favorable in vitro antioxidant properties since its radical scavenging was not significantly different from that of the not-sonicated sample (p > 0.05). In contrast, its metal-chelating activity was significantly higher (p < 0.05). To conclude, post-extraction ultrasonication by an ultrasonic bath for 10 min is recommended to increase phenolic content and improve the antioxidant properties of EAEP.

Preparation of ionic porous polymers for extraction of four phenolic endocrine disrupting chemicals from fish and water samples.

In this paper, series of ionic polymers were synthesized by crosslinking alkyl quaternary ammonium salts with 1,4-bis(chloromethyl)benzene. Among them, hyper-crosslinked polymer fabricated with dodecyl dimethyl benzyl ammonium chloride (HCP-DD) as monomer delivered superior adsorption performance for endocrine disrupting chemicals (EDCs). The adsorption mechanism mainly includes π-π stacking, hydrophobic and electrostatic interaction. With HCP-DD as solid phase extraction sorbent, a high performance liquid chromatography-diode array detection method was developed for the detection of four phenolic EDCs in water and fish samples. The detection limits of the method were 0.005-0.02 ng mL-1 for water samples and 3-30 ng g-1 for fish samples. The recoveries of EDCs in water samples and fish samples were 80-119% and 81.3-117% (relative standard deviations <4.4%), respectively. The study not only provides a route for preparation ionic porous polymers, but also highlights the applications of ionic polymers as efficient adsorbent to enrich organic pollutants.

Exploring the anti-inflammatory, sedative, antidiabetic, and antioxidant potential in in-vitro and in-vivo models and phenolic profiling of Atractylis aristata Batt.

ETHNOPHARMACOLOGICAL RELEVANCE: Atractylis aristata batt., as an endemic plant from the Asteraceae family, holds a significant position in the Ahaggar region of southern Algeria's traditional medicine. The aerial parts of Atractylis aristata was used to cure inflammation, fever, and stomach disorders. AIM OF THE STUDY: The objective of the present investigation was to ascertain the overall bioactive components and phytochemical components and examine the antioxidant, antidiabetic, anti-inflammatory, acute toxicity, and sedative properties of the crude extract obtained from the aerial portions of Atractylis aristata (AaME). MATERIALS AND METHODS: The AaME's antioxidant activity was assessed by the use of pyrogallol autoxidation, (1,1 diphenyl-2-picrylhydrazyl) (DPPH), 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid (ABTS), and reducing power (RP) techniques. 1 mg/mL of AaME was used to evaluate the antidiabetic activity by applying the enzyme α-amylase inhibitory power test. At the same time, the bovine serum albumin (BSA) denaturation method was employed to quantify the in vitro anti-inflammatory activity at different concentrations (1.5625, 0.78125, 0.390625, 0.1953125 and 0.09765625 mg/mL). In contrast, following the Organization for Economic Co-operation and Development (OECD) guideline No. 423, which covers acute oral toxicity testing protocols, the limit dosage test was employed to assess in vivo acute toxicity. At the dose of 0.08 mg/mL, the carrageenan-induced paw edema approach was used to assess the anti-inflammatory efficacy in vivo, and the sedative activity was carried out at the dose of 0.08 mg/mL using the measurement of the locomotor method. Different bioactive compounds were identified within AaME using LC-MS/MS and HPLC-UV analysis. RESULTS: The acute toxicity study showed no fatalities or noticeable neurobehavioral consequences at the limit test; this led to their classification in Globally Harmonized System (GHS) category Five, as the OECD guideline No 423 recommended. At a concentration of 0.08 mg/mL (2000 mg/kg), AaME showed apparent inhibition of paw edema and a significant (p = 0.01227) reduction in locomotor activity compared to the control animals. Our findings showed that AaME exhibited considerable antioxidant (IC50 = 0.040 ± 0.003 mg/mL (DPPH), IC50 = 0.005 ± 5.77 × 10-5 mg/mL (ABTS), AEAC = 91.15 ± 3.921 mg (RP) and IR% = 23.81 ± 4.276 (Inhibition rate of pyrogallol) and rebuts antidiabetic activities (I% = 57.6241% ± 2.81772). Our findings revealed that the maximum percentage of BSA inhibition (70.84 ± 0.10%) was obtained at 1.562.5 mg/mL. Thus, the AaME phytochemical profile performed using phytochemical screening, HPLC-UV, and LC-MS/MS analysis demonstrated that A. aristata can be a valuable source of chemicals with biological activity for pharmaceutical manufacturers. CONCLUSION: The phytochemical profiling, determined through HPLC-UV and LC-MS/MS applications, reveals this plant's therapeutic value. The aerial parts of Atractylis aristata contain bioactive molecules such as gallic acid, ascorbic acid, and quercetin, contributing to its significant antioxidant capabilities. Furthermore, identifying alizarin, the active compound responsible for its anti-inflammatory properties, could provide evidence supporting the anti-inflammatory capabilities of this subspecies.

Ultrasonic-assisted extraction to enhance the recovery of bioactive phenolic compounds from Commiphora gileadensis leaves.

The "ultrasonic-assisted extraction (UAE)" method was utilized in this work to assess how different process parameters affected the yield and recovery of phenolic compounds from the leaf of Commiphora gileadensis, which is one of the medicinal plants with a variety of biological functions. Its leaf is used for a various of therapeutic applications, such as the treatment of bacterial infections, inflammation, and wound healing. The "One-Factor-At-a-Time (OFAT)" approach was employed to examine the impacts of various UAE process parameters on the process of extraction, which include time of extraction, sample/solvent ratio, ultrasonic frequency, and solvent (ethanol) concentration. The extracts were then investigated for the presence of several phytochemicals using analytical techniques such as "Gas Chromatography-Mass Spectroscopy (GC-MS)" and "Fourier Transform Infrared Spectroscopy (FTIR)" studies. The findings showed that the maximum extraction yield, the total phenolic content (TPC), and the total flavonoids content (TFC) of the ethanolic extract of the leaves of C. gileadensis using the UAE method were at 31.80 ± 0.41 %, 96.55 ± 2.81 mg GAE/g d.w. and 31.66 ± 2.01 mg QE/g d.w. accordingly under a procedure duration of 15 min, ultrasonic frequency of 20 kHz, solvent/sample ratio of 1:20 g/mL, and solvent concentration of 40 % v/v. The leaves extract of C. gileadensis included 25 phenolic compounds that were previously unreported, and GC-MS analysis confirmed their presence. Hence, it follows that the UAE technique can successfully extract the phytochemicals from C. gileadensis for a variety of therapeutic uses.

Fibrillization of lentil proteins is impacted by the protein extraction conditions and co-extracted phenolics.

Legume proteins can be induced to form amyloid-like fibrils upon heating at low pH, with the exact conditions greatly impacting the fibril characteristics. The protein extraction method may also impact the resulting fibrils, although this effect has not been carefully examined. Here, the fibrillization of lentil protein prepared using various extraction methods and the corresponding fibril morphology were characterized. It was found that an acidic, rather than alkaline, protein extraction method was better suited for producing homogeneous, long, and straight fibrils from lentil proteins. During alkaline extraction, co-extracted phenolic compounds bound proteins through covalent and non-covalent interactions, contributing to the formation of heterogeneous, curly, and tangled fibrils. Recombination of isolated phenolics and proteins (from acidic extracts) at alkaline pH resulted in a distinct morphology, implicating a role for polyphenol oxidase also in modifying proteins during alkaline extraction. These results help disentangle the complex factors affecting legume protein fibrillization.

Seaweed-derived phenolic compounds as diverse bioactive molecules: A review on identification, application, extraction and purification strategies.

Seaweed, a diverse group of marine macroalgae, has emerged as a rich source of bioactive compounds with numerous health-promoting properties. Among these, phenolic compounds have garnered significant attention for their diverse therapeutic applications. This review examines the methodologies employed in the extraction and purification of phenolic compounds from seaweed, emphasizing their importance in unlocking the full potential of these oceanic treasures. The article provides a comprehensive overview of the structural diversity and biological activities of seaweed-derived phenolics, elucidating their antioxidant, anti-inflammatory, and anticancer properties. Furthermore, it explores the impact of extraction techniques, including conventional methods and modern green technologies, on the yield and quality of phenolic extracts. The purification strategies for isolating specific phenolic compounds are also discussed, shedding light on the challenges and advancements in this field. Additionally, the review highlights the potential applications of seaweed-derived phenolics in various industries, such as pharmaceuticals, cosmetics, and functional foods, underscoring the economic value of these compounds. Finally, future perspectives and research directions are proposed to encourage continued exploration of seaweed phenolics, fostering a deeper understanding of their therapeutic potential and promoting sustainable practices in the extraction and purification processes. This comprehensive review serves as a valuable resource for researchers, industry professionals, and policymakers interested in harnessing the untapped potential of phenolic compounds from seaweed for the betterment of human health and environmental sustainability.

Contribution of Phenolic Compounds to the Antioxidant Activity of Leaf and Flower Extracts of Sinapis pubescens L. subsp. pubescens (Brassicaceae).

Within a study focused on Sinapis pubescens subsp. pubescens wild from Sicily (Italy), an edible species still unexplored, our earlier published work has demonstrated good in vitro antioxidant properties for the flower and leaf hydroalcoholic extracts, exhibiting quite different qualitative-quantitative phenolic profiles. Herein, further research was designed to elucidate the role played by phenolic compounds in the different antioxidant mechanisms highlighted for the extracts. To achieve this goal, the crude extracts were subjected to liquid-liquid partitioning with solvents of increasing polarity; then, the fractions were investigated for their antioxidant properties using different in vitro assays. For both flowers and leaves, the ethyl acetate fractions exhibited the best activity in DPPH and reducing power assays, followed by n-butanol. The total phenolic content determination indicated these fractions as the phenolic-rich ones, which were characterized by HPLC-PDA/ESI-MS analysis. Conversely, the phenolic-rich fractions did not show any chelating activity, which was highlighted for the more hydrophobic ones.

Spice-Derived Phenolic Compounds: Potential for Skin Cancer Prevention and Therapy.

Skin cancer is a condition characterized by the abnormal growth of skin cells, primarily caused by exposure to ultraviolet (UV) radiation from the sun or artificial sources like tanning beds. Different types of skin cancer include melanoma, basal cell carcinoma, and squamous cell carcinoma. Despite the advancements in targeted therapies, there is still a need for a safer, highly efficient approach to preventing and treating cutaneous malignancies. Spices have a rich history dating back thousands of years and are renowned for their ability to enhance the flavor, taste, and color of food. Derived from various plant parts like seeds, fruits, bark, roots, or flowers, spices are important culinary ingredients. However, their value extends beyond the culinary realm. Some spices contain bioactive compounds, including phenolic compounds, which are known for their significant biological effects. These compounds have attracted attention in scientific research due to their potential health benefits, including their possible role in disease prevention and treatment, such as cancer. This review focuses on examining the potential of spice-derived phenolic compounds as preventive or therapeutic agents for managing skin cancers. By compiling and analyzing the available knowledge, this review aims to provide insights that can guide future research in identifying new anticancer phytochemicals and uncovering additional mechanisms for combating skin cancer.

Contribution of Insoluble Bound Antioxidants from Germinated Seeds of Wheat and Spelt to the Nutritional Value of White Bread.

This research aimed to study the dynamic changes in phenolic antioxidants between the germ and the rest of the germinated seed of wheat and spelt and to evaluate the whole grain flour from germinated seeds as a functional supplement. Longer germination resulted in higher TPC, DPPH, and ABTS values when considering the entire germinated seed, while the optimal germination time was not consistent when considering the germ and the remaining germinated seed separately. While in the germinated seed (without germ) the majority of TPC was determined to be bound phenolics (up to 92%), the extractable form dominated in the germ (up to 69%). The most abundant phenolic antioxidants in germinated wheat and spelt seeds, trans-ferulic acid, cis-ferulic acid, and p-coumaric acid, increased significantly with germination. Only breads with 5% germinated spelt or wheat flour were suitable for the production of a food product, showing higher extractable TPC, antioxidant activity, individual phenolic acids, and improved specific volume, and were preferred because of their appearance, aroma, and color. The PCA biplot showed that the addition of 15% and 30% germinated flours had the greatest positive impact on phenolic properties, while breads with the addition of 5% germinated flour had the greatest positive impact on specific volume and color.

Anti-tyrosinase and antimelanogenic effect of cinnamic acid derivatives from Prunus mahaleb L.: Phenolic composition, isolation, identification and inhibitory activity.

ETHNOPHARMACOLOGICAL RELEVANCE: The traditional use of Prunus species against skin diseases and especially for skin lightning cosmeceutical purposes is widespread in many cultures. Prunus mahaleb L. is a well known food plant and used in the baking industry for flavoring. The fruit kernels (endocarp) are used in India for hyperpigmentation. AIM OF THE STUDY: To investigate the chemical composition with the antimelanogenesis effect of P. mahaleb seed and kernel extracts and isolated compounds. MATERIALS AND METHODS: Isolation studies performed from the methanol extracts obtained from kernels and structures were determined using NMR and MS analysis. Antimelanogenesis effect was determined by mushroom tyrosinase assay, cellular tyrosinase assay and melanin content assay using B16F10 murine melanoma cells. RESULTS: Five cinnamic acid derivatives were isolated and their structures (2-O-ß-glucopyranosyloxy-4-methoxy-hydrocinnamic acid (1), cis-melilotoside (2), dihydromelilotoside (3), trans-melilotoside (4), 2-O-ß-glucosyloxy-4-methoxy trans-cinnamic acid (5)) were elucidated using advanced spectroscopic methods. Mushroom tyrosinase enzyme inhibition of extracts, fractions and pure compounds obtained from P. mahaleb kernels were investigated and structure-activity relationship revealed. According to a detailed, comprehensive and validated LC-MS/MS technique analysis, vanilic acid (41.407 mg/g), protocatechuic acid (8.992 mg/g) and ferulic acid (4.962 mg/g) in the kernel ethylacetate fraction; quinic acid (14.183 mg/g), fumaric acid (8.349 mg/g) and aconitic acid (5.574 mg/g) were found as major phenolic compounds in the water fraction. The correlation of trace element copper content in extracts and fractions with mushroom enzyme activity was determined. By examining the enzyme kinetics of the compounds with effective cinnamic acid derivatives, inhibition types and enzyme binding constants Ki were calculated. Compounds 1,3 and 5 exhibited high noncompetitive tyrosinase inhibitory activity against L-tyrosine substrates, with IC50 values of 0.22, 0.31 and 0.37 mM respectively. In addition compounds 1, 3 and 5 showed dose-dependent inhibitory effects on intracellular tyrosinase and melanin levels in α-melanocyte-stimulating hormone (α-MSH)-induced B16F10 melanoma cells. CONCLUSIONS: Potent tyrosinase inhibitory compounds and extracts of P. mahaleb kernels suggest that it could be a new, non-toxic and inexpensive resource for the cosmeceutical industry and in skin diseases associated with hyperpigmentation.

Nine geranylgeranylated derivatives isolated from the roots of Rhus chinensis Mill.

Nine undescribed geranylgeranylated derivatives (chinensens A-G), including malic acid derivative (A) and phenolic derivatives (B-E), as well as two pairs of enantiomers, [(R), (S)]-chinensens F and [(R), (S)]-chinensens G, were isolated from the roots of Rhus chinensis Mill. Their structures were elucidated by UV, IR, HRESIMS, 1D and 2D NMR spectra, as well as optical rotations. The 95% EtOH extract (95% EXT, 500 mg/kg, p. o.) of the roots of Rhus chinensis and the 95% EtOH fraction (95% FRA, 500 mg/kg, p. o.) from the microporous resin column significantly alleviated indomethacin-induced or water immersion-restraint stress-induced damage in rat gastric mucosa with inhibitory rates from 53% to 89%. The racemic mixture (chinensen G) and its enantiomers [(R), (S)]-chinensens G showed weak activities against H+,K+-ATPase (20%-24%) at a concentration of 0.1 mM, respectively.

Untargeted metabolomic profile of recovered bioactive compounds by subcritical water extraction of acerola (Malpighia emarginata DC.) pomace.

The untargeted metabolomics approach was used to compare the chemical profiles of acerola (Malpighia emarginata DC.) pomace extracts. The effect of drying the raw material before subcritical water extraction (SWE) at different temperatures on the yield, phenolic content, and in vitro antioxidant activity was evaluated. The results were compared with those obtained via Soxhlet and the findings suggest that SWE saves time (15 min) and solvent for extracting valuable components as compared to Soxhlet (6 h). An increase in temperature significantly improved the extraction yield (23.9 to 33.4 %), phenolic content (119.1 to 362 mgGAEg-1), and antioxidant activity, and higher values were obtained with SWE as compared to Soxhlet. The most abundant compounds detected by UPLC-ESI-QTOF-MS were ascorbic acid, kaempferol, quercetin, and isorhamnetin. The investigation of different moisture contents in the SWE showed promising results for eliminating the drying operation, saving time and energy, and obtaining highly concentrated phenolic-rich by-products.

An efficient 3D adsorbent foam based on graphene oxide/AgO nanoparticles for rapid vortex-assisted floating solid phase extraction of bisphenol A in canned food products.

In this study, a three-dimensional adsorbent was developed based on graphene oxide/AgO nanoparticles over interconnected nickel foam (GO/AgO@Ni foam) for rapid and efficient vortex assisted floating solid phase extraction of bisphenol A in canned food products prior to high performance liquid chromatography with a fluorescence detector. The analytical techniques scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and Fourier transform infrared (FT-IR) were used for characterization of the synthetized GO/AgO@Ni foam. The effect of proficiency factors including pH, foam size, vortexing time, salt addition, sample volume, desorption type and volume, and desorption time on the extraction efficiency of bisphenol A were explored through the matrix match method. Under the above experimental conditions, the figures of merit of the method were acquired as LODs (S/N = 3) of 0.18-0.84 µg kg-1, LOQs of 0.61-2.81 µg kg-1 (S/N = 10), linear ranges of 0.5-500 µg kg-1, and enrichment factors of 235.5-244.9. The inter-day precision values (RSD%, n = 7) of 2.5-3.6 and the intra-day precision (%) of (5 days and seven replicates for each day) 2.8-3.8 were achieved for bisphenol A at a concentration of 50 µg kg-1. The relative recoveries of 94.0% to 99.6% were obtained for the canned food samples.