Hydroxycinnamic Acids Research Articles

Evaluation of Cytotoxicity of 4-Hydroxycinnamic Acid Using Tetrazolium Bromide Assay and Zebrafish Embryotoxicity: An In-Vitro Study.

Aim This study aimed to evaluate the cytotoxicity of a novel compound, 4-hydroxycinnamic acid (4-HCA), with the help of a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and zebrafish embryotoxicity. Materials and methods In this in vitro study, MTT fibroblast assays using dental pulp stem cells, which were cultured in Modified Eagle's Medium or Dulbecco's Modified Eagle Medium, and zebrafish cytotoxicity and embryotoxicity were done to evaluate the cytotoxicity of the novel compound 4-HCA. The data was analyzed by plotting cell number versus absorbance, allowing quantitation of changes in cell proliferation. Results 4-HCA (40 μl) showed acceptable levels of cell viability according to the American Society for Testing and Materials standards. Cell viability is reduced with increased exposure time and concentrations of 4-HCA. Similarly, the cytotoxicity assessment in zebrafish (Danio rerio) showed an acceptable range of toxicity levels in embryonic stagesused to evaluate the mortality rate of zebrafish embryos. Conclusion Considering the constraints of this research, it can be deduced that hydroxycinnamic acid at a concentration of 40 μl was non-toxic. The findings from the MTT assay indicated a correlation between the concentration and the toxicity of the compound. Likewise, the zebrafish test demonstrated minimal toxicological effects.

Metabolomic Profiling Reveals the Quality Variations in Citri Reticulatae Pericarpium (Citrus reticulata Blanco cv. Chachiensis) with Different Storage Ages in Response to "Candidatus Liberibacter Asiaticus" Infection.

Citri Reticulatae Pericarpium, especially the pericarp of Citrus reticulata Blanco cv. Chachiensis (PCRC), is an important edible and medicinal ingredient for health and pharmacological properties. Citrus Huanglongbing, a devastating disease that currently threatens the citrus industry worldwide, is caused by a phloem-limited alpha-proteobacterium, "Candidatus Liberibacter asiaticus" (CLas). The industry of cultivar Chachiensis has been suffering from HLB. Although HLB affected the quality of citrus fruit, whether the quality of PCRC was affected by HLB remains unclear. In this study, we compared the metabolite profiles between HLB-affected and healthy PCRC from three sources: fresh, 6-month-old, and 9-year-old PCRC, through the untargeted LC-MS method. Compared to healthy controls, various types of bioactive compounds, mainly flavonoids, terpenoids, alkaloids, coumarins, polysaccharides, and phenolic acids, accumulated in HLB-affected PCRC, especially in the HLB-affected 9-year PCRC. In particular, isorhamnetin, isoliquiritigenin, luteolin 7-O-beta-D-glucoside, limonin, geniposide, pyrimidodiazepine, scoparone, chitobiose, m-coumaric acid, malonate, and pantothenic acid, which contributed to the pharmacological activity and health care effects of PCRC, were highly accumulated in HLB-affected 9-year-old PCRC compared to the healthy control. Multibioassay analyses revealed that HLB-affected 9-year-old PCRC had a higher content of total flavonoids and total polyphenols and exhibited similar antioxidant capacity as compared to healthy controls. The results of this study provided detailed information on the quality of HLB-affected PCRC.

Characterization of Azorean Plant Leaves for Sustainable Valorization and Future Advanced Applications in the Food, Cosmetic, and Pharmaceutical Industries.

The historical use of plants as sources of natural compounds has persisted over time. Increasing the intake of bioactive substances shows significant potential for promoting overall well-being and health. This study delves into the pigments, phenolic composition, and profile, along with antioxidant properties, of leaf extracts rich in bioactives from plants in the Azores region, contributing to sustainable primary food production. Analyses encompassed chlorophylls, carotenoids, total phenols, ortho-diphenols, and flavonoids, as well as antioxidant capacity assessment, polyphenolic profiling, and quantification. Psidium guajava L. and Smallanthus sonchifolius (Poepp.) H.Rob. exhibited elevated chlorophyll content, while Colocasia esculenta (L.) Schott displayed the highest carotenoid levels. Annona cherimola Mill., Eriobotrya japonica (Thunb.) Lindl, and Psidium guajava L. demonstrated pronounced total phenols, ortho-diphenols, and flavonoids. These findings align with heightened antioxidant capacity. HPLC-DAD (high-performance liquid chromatography with diode-array detection) characterization unveiled elevated hydroxycinnamic acids in E. japonica and Ipomea batatas (L.) Lam. compared to A. cherimola Mill., while C. esculenta exhibited increased flavone content. Among the quantified compounds, flavonols were the ones that predominantly demonstrated contribution to the antioxidant capacity of these leaves. This research highlights Azorean leaf plants' antioxidant potential, fostering natural product development for better health.

Bioactive polyphenolic compounds and antioxidant potentials of two leafy vegetables in Bangladesh: the Momordica charantia and the Ipomoea aquatica

Momordica charantia and Ipomoea aquatica leaves are two green leafy vegetables in Bangladesh that are commonly consumed considering their characteristic taste and abundant availability in nature. The aim of this study was to determine the available bioactive phenolic constituents as well as total flavonoid content (TFC), tannin content (TTC), phenolic content (TPC), antioxidant activity (TAA) and DPPH radical scavenging activity (IC50) of the ethanolic extracts of M. charantia (MCE) and I. aquatica (IAE). HPLC–DAD and UV–visible spectrophotometer were used to determine the phenolic compounds and antioxidant properties, respectively. In this study, TFC, TTC, TPC, TAA and IC50 values were in the order of IAE (40.73 ± 1.0 mg QE/g) > MCE (34.60 ± 0.46 mg QE/g); MCE (40.93 ± 0.70 mg TAE/g) > IAE (31.13 ± 0.42 mg TAE/g); MCE (27.76 ± 0.58 mg GAE/g) > IAE (21.29 ± 0.43 mg GAE/g); MCE (52.03 ± 0.21 mg AAE/g) > IAE (40.77 ± 0.15 mg AAE/g) and MCE (333.22 ± 67.37 µg/mL) > IAE (560.74 ± 10.25 µg/mL). M. charantia ethanolic extracts contained five hydroxycinnamic acid: ferulic acid, chlorogenic acid, p-coumaric acid, rosmarinic acid and cinnamic acid; five flavonoids: epicatechin, quercetin, catechin, rutin hydrate and myricetin; two hydroxybenzoic acid: gallic acid and vanillic acid; and one phenolic aldehyde: vanillin. Whereas, I. aquatica extracts possessed four hydroxycinnamic acid: chlorogenic acid, p-coumaric acid, trans-ferulic acid and trans-cinnamic acid; four flavonoids: epicatechin, quercetin, catechin, and rutin hydrate; two hydroxybenzoic acid: gallic acid and vanillic acid; and one phenolic aldehyde:vanillin. These underutilised sources of leafy vegetables may be used to develop functional foods by emphasising their remarkable bioactive components.Graphical

Inoculation with a selected strain of <i>Metschnikowia pulcherrima</i> as a bioprotective alternative to sulphites for preventing browning of white grape must

In this study, the effectiveness of a selected strain of Metschnikowia pulcherrima (MP1) was compared to that of sulphur dioxide for preventing white grape must from browning. Sulphur dioxide was found to drastically reduce oxygen consumption rate, protect hydroxycinnamic acids against oxidation and prevent grape must from browning, even in the presence of laccase. By contrast, supplementation with the selected strain of Metschnikowia pulcherrima (MP1) drastically increased oxygen consumption rate, thus reducing the amount of oxygen available for polyphenol oxidases. In the absence of laccase, this resulted in a decrease in browning and a certain degree of protection of the hydroxycinnamic acids, but in the presence of laccase it was not effective enough. Consequently, the selected strain of Metschnikowia pulcherrima (MP1) can be considered an interesting alternative to sulphur dioxide for preventing browning in white grape must, but only in conditions of healthy grapes.

Enzymatic Synthesis of Hydroxycinnamic Acid Amides in Water Using the Promiscuous Hydrolase/Acyltransferase PestE from Pyrobaculum calidifontis VA1

AbstractHydroxycinnamic acid amides are believed to have antioxidant, antidiabetic, cytotoxic, anticancer, neuroprotective, and antiinflammatory properties, making them interesting target molecules for potential applications in the food, cosmetics, and pharmaceutical industries. Here, we describe the synthesis of hydroxycinnamic acid amides starting from hydroxycinnamic acid esters and the corresponding amines by using variants of the promiscuous hydrolase/acyltransferase from Pyrobaculum calidifontis VA1 (PestE) in water as a solvent. Up to 97% conversion within two hours at 60 °C was achieved with methyl ferulate and tyramine as substrates. This is a promising, environmentally friendly alternative strategy to established chemical synthesis routes or enzymatic methods using lipases in nonaqueous organic solvents.

Mentha Pulegium: A Plant with Several Medicinal Properties.

The species Mentha Pulegium L. (M. pulegium L.) belongs to the family Lamiaceae, native to Europe, North Africa, and the Middle East, and the genus Mentha. It has been traditionally used in food, cosmetics, and medicines. It is a perennial, fragrant, well-liked, herbaceous plant that can grow up to half a meter tall. It is extensively used as a food flavoring, particularly for Moroccan traditional drinks. Chewing mint and M. pulegium, a relaxing and refreshing plant, can be used to treat hiccups and act as an anticonvulsant and nerve relaxant. Pennyroyal leaves that have been crushed have a pungent, spearmint-like scent. Pennyroyal is used to make herbal teas, which, while not proven to be harmful to healthy adults in small doses, are not recommended due to their liver toxicity. Infants and children can die if they consume it. Pennyroyal leaves, both fresh and dried, are particularly effective at repelling insects. Pennyroyal essential oil should never be taken internally because it is highly toxic, even in small doses, it can be fatal. This plant is used in traditional Moroccan medicine to treat a wide range of conditions, including influenza, rheumatism, migraine, infertility, ulcer, pain, gastrointestinal problems, fever, diabetes, obesity, mental and cardiac disorders, constipation, respiratory ailments, and cough. M. pulegium is a great candidate for contemporary therapeutic usage since it contains a wide variety of biologically active compounds, including terpenoids, flavonoids, alkaloids, tannins, and saponins in all its parts. Among the different parts used are the whole plant, the aerial part, the stem, and the leaves. More interestingly, the entire plant contains a variety of compounds including Pulegone, Isomenthone, Carvone, Menthofuran, Menthol, 1,8-Cineole, Piperitone, Piperitenone, Neomenthol, -humulene, and 3-octanol. Eriocitrin, Hesperidin, Narirutin, Luteolin, Isorhoifolin, Galic acid, and Rosmarinic acid are found in the leaves. p-hydroxybenzoic acid, Ferulic acid, Caffeic acid, Vanillic acid, Syringic acid, Protocatechuic acid, Cinnamic acid, Phloretic acid, o-coumaric acid, p-coumaric acid, Catechin, Epicatechin, Chrysin, Quercetin, Naringenin, Carvacrol are all found in the areal part. Alterporriol G, Atropisomer, Alterporriol H, Altersolanol K, Altersolanol L, Stemphypyrone, 6-O-methylalaternin, Macrosporin, Altersolanol A, Alterporriol E, Alterporriol D, Alterporriol A, Alterporriol B, and Altersolanol J are also found in the stem of fungus. Pulegone, Piperitone, p-Menthane-1,2,3- triol, β-elemenene, guanine (cis-), Carvacrol acetate, and Phenyl ethyl alcohol are all components of this plant's essential oils. Moreover, the study also sought to investigate and document all currently available evidence and information on the nutritional composition and therapeutic uses of this plant ornamental. Its pharmacological applications include antimicrobial, antioxidant, antihypertensive, antidiabetic, anti-inflammatory, antiproliferative, antifungal, anticancer, burn wound healing, antispasmodic, and hepatotoxicity. Finally, toxicological studies have revealed that while low doses of extracts of the plant M. pulegium are not toxic, however, its essential oils of it are extremely toxic. In order to evaluate future research needs and investigate its pharmacological applications through clinical trials, the current assessment focuses on the distribution, chemical composition, biological activities, and primary uses of the plant.

Biomorphological features and antioxidant activity of mint species of non-hybrid origin growing in the North Caucasus region

Introduction. Modern researchers note the role of antioxidants in the correction of fat and carbohydrate metabolism, so the search for new raw materials for obtaining substances with antioxidant activity is relevant. Polyphenolic compounds are considered the most powerful natural antioxidants. Our attention was drawn to non-hybrid mint species growing in the North Caucasus region. Objective. Study of biomorphological features and economically valuable characteristics of the species Mentha L. (Lamiaceae), their phytochemical characteristics based on the content of essential oil and some phenolic compounds, determination of antioxidant activity to substantiate the prospects for use in medicine and pharmacy. Material and methods. The studies were carried out according to the methods of the State Pharmacopoeia (SP) XIV and XV editions. Samples of raw mint (M. arvensis L.), watermint (M. aquatica L.), longleaf mint (M. longifolia (L.) Huds.), flea mint (M. pulegium L.), m spicata (M. spicata L.), harvested in forest-steppe and steppe zones, as well as on mountain slopes, damp places, sometimes in wastelands, in North Ossetia – Alania, Karachay-Cherkessia, Kabardino-Balkaria and the Stavropol Territory in their natural places of growth (end of July–August 2021–2023). Objects were dried using the air-shadow method. Antioxidant activity was determined by amperometric and titrimetric methods. Results. Non-hybrid mint species growing in the North Caucasus contain essential oils, hydroxycinnamic and triterpene acids, flavonoids and polyphenolic compounds. The established antioxidant properties of hydroalcoholic extracts of mint species, in addition to the traditionally known choleretic and antispasmodic effects, can be considered significant for reducing body weight. Conclusion. The content of essential oil and polyphenolic compounds in various types of mint, as well as the established antioxidant properties of aqueous-alcoholic extracts, in addition to the traditionally known choleretic and antispasmodic effects, can be considered significant for weight loss.

Exploration of the Diversity of Vicine and Convicine Derivatives in Faba Bean (Vicia faba L.) Cultivars: Insights from LC-MS/MS Spectra.

While numerous Fabaceae seeds are a good nutritional source of high-quality protein, the use of some species is hampered by toxic effects caused by exposure to metabolites that accumulate in the seeds. One such species is the faba or broad bean (Vicia faba L.), which accumulates vicine and convicine. These two glycoalkaloids cause favism, the breakdown of red blood cells in persons with a glucose-6-phosphate dehydrogenase deficiency. Because this is the most common enzyme deficiency worldwide, faba bean breeding efforts have focused on developing cultivars with low levels of these alkaloids. Consequently, quantification methods have been developed; however, they quantify vicine and convicine only and not the derivatives of these compounds that potentially generate the same bio-active molecules. Based on the recognition of previously unknown (con)vicine-containing compounds, we screened the fragmentation spectra of LC-MS/MS data from five faba bean cultivars using the characteristic fragments generated by (con)vicine. This resulted in the recognition of more than a hundred derivatives, of which 89 were tentatively identified. (Con)vicine was mainly derivatized through the addition of sugars, hydroxycinnamic acids, and dicarboxylic acids, with a group of compounds composed of two (con)vicine residues linked by dicarboxyl fatty acids. In general, the abundance profiles of the different derivatives in the five cultivars mimicked that of vicine and convicine, but some showed a derivative-specific profile. The description of the (con)vicine diversity will impact the interpretation of future studies on the biosynthesis of (con)vicine, and the content in potentially bio-active alkaloids in faba beans may be higher than that represented by the quantification of vicine and convicine alone.

Identification of Hsp90 inhibitors from Ananas comosus potential phytochemicals for lung cancer treatment

Lung cancer is a significant global health issue, with thousands of lives lost each year. One potential approach to preventing lung cancer is the use of heat shock protein 90 (Hsp90) inhibitors, which have been shown to induce substantial cell death in both chemo-sensitive and chemo-resistant small cell lung cancer cells. In this study, we conducted in silico computational molecular docking of pineapple phytochemicals with Hsp90 to investigate their potential inhibitory effects on Hsp90 and, consequently, their ability to prevent lung cancer. Our findings demonstrate that the phytochemicals found in Ananas comosus, specifically caffeic acid, ferulic acid, 4-Hydroxycinnamic acid, Sinapic acid, and D-Galacturonic Acid, exhibit notable inhibitory activity against Hsp90. Beyond their Hsp90 inhibition, these phytochemicals also demonstrate promising biological activities, serving as effective agents against neoplastic conditions, particularly lung cancer, and displaying pro-apoptotic properties. Moreover, the ADME (Absorption, Distribution, Metabolism, and Excretion) and toxicological assessments conducted on these compounds yielded satisfactory results. These findings suggest that pineapple phytochemicals may have potential in the development of novel therapeutic strategies for lung cancer prevention.

Phytochemical evaluation and exploration of some biological activities of aqueous and ethanolic extracts of two species of the genus Plantago L.

Plantago major L. and Plantago lagopus L. are cosmopolitan species, belonging to the Plantaginaceae family, used in traditional and modern medicine. In this study, a phytochemical evaluation of different aqueous and ethanolic extracts of leaves and roots of both species from the region of Beja in Tunisia was performed. Some biological activities, including antioxidant, anticancer and antibacterial were also done. LC-MS qualitative analysis revealed that the aqueous extracts of the roots of P. lagopus were richer in polyphenols, mainly flavonoids (Luteoline 7-rutinoside, Luteoline 7-rhamnoside) and hydroxycinnamic acids including caffeic acid, than the hydro-ethanolic extracts. Additionally, we identified for the first time the presence of salicylic acid in the hot aqueous extracts of roots of P. lagopus and its absence in the roots of P. major. The antioxidant activity of the extracts was assessed using cyclic voltammetry (CV), revealing that the voltammograms of leaf and root extracts from P. lagopus exhibited a higher antioxidant capacity compared to those of P. major. Antiproliferative activity, was determined against two-colon cancer cell lines, demonstrated that only the 12 h treatments with P. lagopus leaf and root aqueous and hydro-ethanolic extracts at low concentration were able to significantly reduce the colon carcinoma coli-2 (CaCo-2) cells proliferation. The antibacterial /antibiofilm activity was performed on yeast, Gram- negative and +positive bacterial strains. We demonstrated for the first time that ethanolic extracts of leaves and roots of P. lagopus have an inhibitory activity against Escherichia coli and Klebsiella pneumonia at MIC = 2 μg/mL for leaves and 4 μg/mL for roots.

ANCUT1, a novel thermoalkaline cutinase from Aspergillus nidulans and its application on hydroxycinnamic acids lipophilization

One of the four cutinases encoded in the Aspergillus nidulans genome, ANCUT1, is described here. Culture conditions were evaluated, and it was found that this enzyme is produced only when cutin is present in the culture medium, unlike the previously described ANCUT2, with which it shares 62% amino acid identity. The differences between them include the fact that ANCUT1 is a smaller enzyme, with experimental molecular weight and pI values of 22 kDa and 6, respectively. It shows maximum activity at pH 9 and 60 °C under assayed conditions and retains more than 60% of activity after incubation for 1 h at 60 °C in a wide range of pH values (6–10) after incubations of 1 or 3 h. It has a higher activity towards medium-chain esters and can modify long-chain length hydroxylated fatty acids constituting cutin. Its substrate specificity properties allow the lipophilization of alkyl coumarates, valuable antioxidants and its thermoalkaline behavior, which competes favorably with other fungal cutinases, suggests it may be useful in many more applications.

Chromatographic analysis of flavonoids and phenolic acids in the herb Ocimum sanctum L.

The genus Basil (Ocimum L.), which belongs to the Mint (Lamiaceae Martinov) family, includes more than 70 species and several subspecies of herbaceous plants and subshrubs. In wild nature, they are common on almost all continents in tropical and subtropical regions, less often in temperate climates. Holy basil (Ocimum sanctum L.) is most often used in folk medicine of various countries. The medicinal properties of this plant are determined mainly by the essential oil and polyphenols. As it is known, the chemical composition of plant raw materials can vary significantly depending on genetic characteristics (subspecies, chemotype) as well as on soil and climatic conditions during its cultivation.
 This study aimed to determine the chromatographic profile of flavonoids and phenolic acids in the Ocimum sanctum herb during its cultivation in the conditions of the Ternopil Region (Ukraine). The aerial part of the studied plant was harvested at the beginning of flowering in the summer of 2023. The dried raw material was crushed and sifted through a sieve. The chromatographic profile of flavonoids and phenolic acids was determined by high-performance liquid chromatography (HPLC) using an Agilent Technologies 1200 chromatograph. The raw material was extracted using 80% methanol in an ultrasonic bath. Identification and quantitative analysis were carried out using solutions of standard samples of flavonoids and phenolic acids. Calibration was carried out by the method of external standards.
 It was revealed that the Ocimum sanctum herb contains eight phenolic acids, among which hydroxycinnamic rosmarinic acid (10 453.48 μg/g) dominated. In general, the content of hydroxycinnamic acids in the raw material of the studied species was significantly higher than that of hydroxybenzoic acids. Among the six identified flavonoids, the highest content was determined for the flavanone neohesperidin (11 720.79 μg/g); the content of other flavonoids, in particular, flavonol derivatives (quercetin, rutin, quercetin-3-O-glycoside, kaempferol-3-O-glycoside) and flavone (luteolin) was significantly lower.
 Considering the significant therapeutic potential of the predominant phenolic compounds, the planning of further pharmacological studies of phytosubstances based on the raw material of the studied species deserves attention.

Soybean and maize differentially metabolize deuterated ferulic and sinapic acids before polymerizing them into the root cell wall

Hydroxycinnamates induce lignification in young plants, leading to the overproduction of lignin as a defense mechanism. Phenylpropanoids-containing oligosaccharides are thought to be a signal of pathogen attack on the cell wall polysaccharides. However, it is unclear if hydroxycinnamates induce lignification by acting solely as stress elicitors or feeding the phenylpropanoid pathway as lignin precursors. To examine this hypothesis, we added 1 mM deuterated ferulic acid (FA) or sinapic acid (SA) to the nutrient solution in which we cultivated soybean or maize plantlets. After 24 h, we assessed the biometric parameters and the contents of ester-linked FA and SA, total lignin, monolignol ratio, and heavy monolignols. FA treatment increased the content of ester-linked FA, syringyl, and guaiacyl monomers measured by nitrobenzene oxidation, lignin content, and reduced root growth in both soybean and maize plants. p-Coumaric acid content ester-linked to the cell wall increased in soybean but decreased in maize after treatment with FA. Treatment with SA also induced lignification in soybean but not in maize. SA increased S-lignin and sinapoyl esters content in the cell wall polymers in both soybean and maize. Residues of deuterated hydroxycinnamates were detected in the lignin of both plants in both treatments. The assay demonstrated that exogenously applied SA and FA were metabolized through the phenylpropanoid pathway. Furthermore, they were, at least partially, exported to the apoplast, where they were ester-linked to cell wall polymers. This suggests hydroxycinnamic acids are metabolized differently by plants with different types of cell walls.

Rosmarinic Acid Present in Lepechinia floribunda and Lepechinia meyenii as a Potent Inhibitor of the Adenylyl Cyclase gNC1 from Giardia lamblia.

Giardiasis is a parasitosis caused by Giardia lamblia with significant epidemiological and clinical importance due to its high prevalence and pathogenicity. The lack of optimal therapies for treating this parasite makes the development of new effective chemical entities an urgent need. In the search for new inhibitors of the adenylyl cyclase gNC1 obtained from G. lamblia, 14 extracts from Argentinian native plants were screened. Lepechinia floribunda and L. meyenii extracts exhibited the highest gNC1 inhibitory activity, with IC50 values of 9 and 31 µg/mL, respectively. In silico studies showed rosmarinic acid, a hydroxycinnamic acid present in both mentioned species, to be a promising anti-gNC1 compound. This result was confirmed experimentally, with rosmarinic acid showing an IC50 value of 10.1 µM. Theoretical and experimental findings elucidate the molecular-level mechanism of rosmarinic acid, pinpointing the key interactions stabilizing the compound-enzyme complex and the binding site. These results strongly support that rosmarinic acid is a promising scaffold for developing novel compounds with inhibitory activity against gNC1, which could serve as potential therapeutic agents to treat giardiasis.

Changes in Chemical Composition of Red and Black Currant Fruits and Leaves During Berry Ripening

ABSTRACT The composition and variations of sugars, organic acids and phenolic compounds of red and black currant fruits and leaves were studied during the last four weeks of ripening. The results showed that sugar content increased during berry ripening in both species. In comparison, organic acids decreased in red currant, whereas no differences between sampling dates were observed in black currant. Forty-seven individual phenolic compounds, belonging to anthocyanins, flavonols, flavanols, hydroxycinnamic acid derivatives and flavanones were identified in red currant fruits and 52 in black currant fruits by HPLC-MS analysis. In black currant fruits, the major phenolic compounds were anthocyanins (81.51–85.15% of total phenolics), which increased during ripening until the last sampling date. In both red and black currant leaves, 47 phenolic compounds were identified. The content of phenolic compounds in red currant leaves was 1.31-fold to 1.90-fold higher compared to the content in black currant leaves. The most abundant phenolics in both currant leaves were flavonol glycosides, accounting for 58.5–67.9% of total phenolics, and their content was the highest at the end of berry ripening.

Choline chloride-based deep eutectic solvents (NADES): Potential use as green extraction media for polyphenols from Mentha pulegium, antioxidant activity, and antifungal activity

With the introduction of the concept of green chemistry, eco-friendly extraction processes are moving from an option to a must. Combined with ultrasound-assisted extraction (UAE), 9 choline chloride deep eutectic solvents were screened for the extraction of antioxidant polyphenolic compounds from Mentha pulegium (Lamiaceae). Data indicated that among the 9 types of choline chloride-based solvents tested, Choline Chloride: Lactic acid (1:2) and Choline Chloride: Glycerol (1:2) were selected as the most promising solvent compared to 80 % methanol. The extraction conditions were statistically investigated using Response surface methodology conducted by Boc-Behnken design (BBD). The optimal operational conditions were: temperature of extraction 80 °C, extraction time of 30 and 51 min with 44 and 20 % water content in Choline Chloride: Glycerol (1:2) and Choline Chloride: Lactic acid (1:2), respectively. The selected NADES extracts recorded excellent scavenging activity at a concentration of 1,9 mg/ml higher than 93 %. HPLC–MS/MS analysis revealed that Phenolic acids mainly hydroxycinnamic acids, such as rosmarinic acid, chlorogenic acid, salvianolic acid, caffeoyl glucose, lithospermic acid, and its derivatives, dominated the extracts tested. Otherwise, our results support that the proposed eutectic solvents are able to provide a higher selectivity toward flavonoids such as apigenin derivative, kaempferol coumaroyl hexoside, epi gallocatechin and quercetin o glucopyranoside gallate. The antifungal activity of the optimized extracts revealed inhibition of over than 88 % against the postharvest citrus fungal: Phytophthora citrophthora. In light of the presented results and considering the nature of components constituting Natural deep eutectic solvents (NADES), make these green, novel, sustainable, and low-cost extracts fresh samples for further investigation.

Grass lignin: biosynthesis, biological roles, and industrial applications.

Lignin is a phenolic heteropolymer found in most terrestrial plants that contributes an essential role in plant growth, abiotic stress tolerance, and biotic stress resistance. Recent research in grass lignin biosynthesis has found differences compared to dicots such as Arabidopsis thaliana. For example, the prolific incorporation of hydroxycinnamic acids into grass secondary cell walls improve the structural integrity of vascular and structural elements via covalent crosslinking. Conversely, fundamental monolignol chemistry conserves the mechanisms of monolignol translocation and polymerization across the plant phylum. Emerging evidence suggests grass lignin compositions contribute to abiotic stress tolerance, and periods of biotic stress often alter cereal lignin compositions to hinder pathogenesis. This same recalcitrance also inhibits industrial valorization of plant biomass, making lignin alterations and reductions a prolific field of research. This review presents an update of grass lignin biosynthesis, translocation, and polymerization, highlights how lignified grass cell walls contribute to plant development and stress responses, and briefly addresses genetic engineering strategies that may benefit industrial applications.

The Conjugates of Indolo[2,3-b]quinoline as Anti-Pancreatic Cancer Agents: Design, Synthesis, Molecular Docking and Biological Evaluations.

New amide conjugates of hydroxycinnamic acids (HCAs) and the known antineoplastic 5,11-dimethyl-5H-indolo[2,3-b]quinoline (DiMIQ), an analog of the natural alkaloid neocryptolepine, were synthesized and tested in vitro for anticancer activity. The compound 9-[((2-hydroxy)cinnamoyl)amino]-5,11-dimethyl-5H-indolo[2,3-b]quinoline (2), which contains the ortho-coumaric acid fragment, demonstrated dose-dependent effectiveness against both normal BxPC-3 and metastatic AsPC-1 pancreatic cancer cells. The IC50 values for AsPC-1 and BxPC-3 were 336.5 nM and 347.5 nM, respectively, with a selectivity index of approximately 5 for both pancreatic cancer cells compared to normal dermal fibroblasts. Conjugate 2 did not exhibit any hemolytic activity against human erythrocytes at the tested concentration. Computational studies were performed to predict the pharmacokinetic profile and potential mechanism of action of the synthesized conjugates. These studies focused on the ADME properties of the conjugates and their interactions with DNA, as well as DNA-topoisomerase alpha and beta complexes. All of the conjugates studied showed approximately one order of magnitude stronger binding to DNA compared to the reference DiMIQ, and approximately two orders of magnitude stronger binding to the topoisomerase II-DNA complex compared to DiMIQ. Conjugate 2 was predicted to have the strongest binding to the enzyme-DNA complex, with a Ki value of 2.8 nM.

Stability Increase of Phenolic Acid Decarboxylase by a Combination of Protein and Solvent Engineering Unlocks Applications at Elevated Temperatures.

Enzymatic decarboxylation of biobased hydroxycinnamic acids gives access to phenolic styrenes for adhesive production. Phenolic acid decarboxylases are proficient enzymes that have been applied in aqueous systems, organic solvents, biphasic systems, and deep eutectic solvents, which makes stability a key feature. Stabilization of the enzyme would increase the total turnover number and thus reduce the energy consumption and waste accumulation associated with biocatalyst production. In this study, we used ancestral sequence reconstruction to generate thermostable decarboxylases. Investigation of a set of 16 ancestors resulted in the identification of a variant with an unfolding temperature of 78.1 °C and a half-life time of 45 h at 60 °C. Crystal structures were determined for three selected ancestors. Structural attributes were calculated to fit different regression models for predicting the thermal stability of variants that have not yet been experimentally explored. The models rely on hydrophobic clusters, salt bridges, hydrogen bonds, and surface properties and can identify more stable proteins out of a pool of candidates. Further stabilization was achieved by the application of mixtures of natural deep eutectic solvents and buffers. Our approach is a straightforward option for enhancing the industrial application of the decarboxylation process.