Caffeic Research Articles

AS ATIVIDADES ANTIOXIDANTES DA PERESKIA ACULEATA MILLER

Ora-pro-nóbis (Pereskia aculeata Miller), a plant native to Brazil, is valued in traditional medicine for its nutritional and therapeutic properties. Recently, scientific interest has grown, particularly due to its antioxidant activities. It is rich in vitamins, iron, and proteins and has shown therapeutic effects such as wound healing and treatment of gastrointestinal diseases. Identified bioactive compounds include phenolic acids, like caffeic acid, and flavonoids, such as quercetin and kaempferol. Studies demonstrate high antioxidant and antimicrobial activity, with effectiveness in inhibiting both Gram-positive and Gram-negative bacteria. The plant's mucilage, known for its water retention capacity, is valuable in the food industry as a thickening and stabilizing agent and also has wound-healing properties, leading to its use in ointments. The biopolymers found, such as arabinogalactans, have potential applications in food and pharmaceutical additives. Ora-pro-nóbis is a rich source of bioactive compounds with potential for new nutraceutical and pharmaceutical products, promoting health and disease prevention.

RETRACTION: Protective Effects of Caffeic Acid on Lactate Dehydrogenase Isoenzymes, Electrocardiogram, Adenosine Triphosphatases, and Hematology on Isoproterenol-Induced Myocardial Infarcted Rats.

K. Senthil Kumaran and P. Stanely Mainzen Prince, "Protective Effects of Caffeic Acid on Lactate Dehydrogenase Isoenzymes, Electrocardiogram, Adenosine Triphosphatases, and Hematology on Isoproterenol-Induced Myocardial Infarcted Rats," Journal of Biochemical and Molecular Toxicology 25, no. 2 (2011): 60-67, https://doi.org/10.1002/jbt.20359. The above article, published online on 05 April 2011 in Wiley Online Library (wileyonlinelibrary.com), has been retracted by agreement between the journal Editor-in-Chief, Hari K. Bhat; and Wiley Periodicals, LLC. The retraction has been agreed following an investigation into concerns raised by a third party, which revealed that the western blot in Figure 1 has been published in another article by one of the same authors. The duplicated blots in the two articles represent different experiments. The authors did not provide an explanation or their original data. The editors consider the results and conclusion reported in this article unreliable.

A Beneficial Role of Caffeic Acid on Cardiovascular Complication Associated with Type-1 Diabetes Mellitus in Rats

A Beneficial Role of Caffeic Acid on Cardiovascular Complication Associated with Type-1 Diabetes Mellitus in Rats

Metabolite of esculetin plays an important role in cytotoxic effects induced by chloroquine on porcine immature Sertoli cells

Chloroquine (CQ) is widely used in the therapy against malarial, tumor and recently the COVID-19 pandemic, as a lysosomotropic agent to inhibit the endolysosomal trafficking in the autophagy pathway. We previously reported that CQ (20 μM, 36 h) could reprogram transcriptome, and impair multiple signaling pathways vital to porcine immature Sertoli cells (iSCs). However, whether CQ treatment could affect the metabolomic compositions of porcine iSCs remains unclear. Here, we showed that CQ (20 μM, 36 h) treatment of porcine iSCs induced significant changes of 63 metabolites (11 up and 52 down) by the metabolomics method, which were involved in different metabolic pathways. Caffeic acid and esculetin, the top two up-regulated metabolites, were validated by ELISA. The combined analysis of metabolomics and transcriptome showed caffeic acid and esculetin to be highly correlated with multiple differentially expressed genes (DEGs), including Ndrg1, S100a8, Sqstm1, S100a12, S100a9, Ill1, Lif, Ntn4 and Peg10. Furthermore, esculetin treatment (53 nM, 36 h) significantly decreased the viability and proliferation, suppressed the mitochondrial function, whereas promoted the apoptosis of porcine iSCs, similar to those by CQ treatment (20 μM, 36 h). Collectively, our results showed that CQ treatment induces metabolic changes, and its effect on porcine iSCs could be partially mediated by esculetin.

Unveiling the therapeutic potential of Haloxylon articulatum extract: a comprehensive study on its phytochemical composition, antioxidant, antifungal, and antibacterial activities

ABSTRACT Haloxylon articulatum, commonly known as the salt tree have diverse medicinal benefits. The phytochemical content, antioxidant, antibacterial, and antifungal properties of the methanolic extract were assessed. The extract demonstrated a high concentration of flavonoids and phenolic components, with a Total Flavonoid Content (TFC) of 186 ± 3 µg QE/mg extract and a Total Phenolic Content (TPC) of 188.1 ± 0.4 µg GAE/mg extract. Bioactive substances with anti-inflammatory and antioxidant qualities, such as quercetin, rutin, chrysin, and caffeic acid, were detected by LC-MS analysis. Through IC50 values of 28.88, 14.13, and 23.03 µg/mL for DPPH, β-carotene, and ABTS tests, respectively, the extract demonstrated considerable antioxidant activity. Antibacterial activity was reported against Escherichia coli and Staphylococcus aureus, with bactericidal effects indicated by MIC and MBC values. The extract also exhibited potent antifungal activity against Thielaviopsis paradoxa and Alternaria sp. These results suggest that H. articulatum extract is a promising source of natural antioxidants and antimicrobial agents with potential therapeutic applications.

In Vitro Wound-Healing Potential of Phenolic and Polysaccharide Extracts of Aloe vera Gel.

The present study aimed to conduct a comparative investigation of the biological properties of phenolic and polysaccharide extracts obtained using an ultrasound-assisted technique from Aloe vera gel and their effects on each stage of the wound healing process in in vitro experimental models. HPLC analysis showed that the phenolic extract contained aloin, ferulic, and caffeic acid, as well as quercetin dihydrate, as major compounds. Capillary zone electrophoresis indicated the prevalence of mannose and glucose in the polysaccharide extract. Cell culture testing revealed the anti-inflammatory properties of the phenolic extract at a concentration of 0.25 mg/mL through significant inhibition of pro-inflammatory cytokines-up to 28% TNF-α and 11% IL-8 secretion-in inflamed THP-1-derived macrophages, while a pro-inflammatory effect was observed at 0.5 mg/mL. The phenolic extract induced 18% stimulation of L929 fibroblast proliferation at a concentration of 0.5 mg/mL, enhanced the cell migration rate by 20%, and increased collagen type I synthesis by 18%. Moreover, the phenolic extract exhibited superior antioxidant properties by scavenging free DPPH (IC50 of 2.50 mg/mL) and ABTS (16.47 mM TE/g) radicals, and 46% inhibition of intracellular reactive oxygen species (ROS) production was achieved. The polysaccharide extract demonstrated a greater increase in collagen synthesis up to 25%, as well as antibacterial activity against Staphylococcus aureus with a bacteriostatic effect at 25 mg/mL and a bactericidal one at 50 mg/mL. All these findings indicate that the phenolic extract might be more beneficial in formulations intended for the initial phases of wound healing, such as inflammation and proliferation, while the polysaccharide extract could be more suitable for use during the remodeling stage. Moreover, they might be combined with other biomaterials, acting as efficient dressings with anti-inflammatory, antioxidant, and antibacterial properties for rapid recovery of chronic wounds.

Reduced graphene oxide foams modified with caffeic acid for water decontamination: Capture and safe storage of Hg2+

Graphene-based materials are attractive adsorbents for water decontamination. In this work, we have produced eco-friendly reduced graphene oxide (rGO)-based sorbents by the hydrothermal reduction of graphene oxide (GO) in presence of caffeic acid (CA) and further modification with chitosan (CA_CS). Scanning electron microscopy observations show porous macrostructures that turn more compact after CA or CA_CS modification. The specific surface area achieves a maximum value of 293 m2 g−1 for the pristine rGO foam. The macropores are mainly distributed in a range between 1–170 µm. The Hg2+ removal efficiency of the rGO-based foams was investigated across several different parameters. The foam modified with caffeic acid exhibited the most promising performance, demonstrating the highest removal efficiency at pH 4–6, with a maximum sorption capacity of 2.79 mg/g as determined by the Sips equation. Kinetic analysis indicates that intraparticle diffusion and the sorption itself are the rate-limiting steps. The notable sorption efficiency, the low desorption rate, and the applicability in real complex water matrices, including tap water, position rGO_CA as a viable material for efficiently capturing Hg(II) from large volumes of water and securely storing it in a small solid volume.

Valorization of Date By-Products: Enhancement of Antioxidant and Antimicrobial Potentials through Fermentation.

The by-products from three varieties of dates-Mozafati, Sayer, and Kabkab-were subjected to solid-state fermentation using Aspergillus niger alone or in co-culture with Lactiplantibacillus plantarum or Limosilactobacillus reuteri to enhance their phenolic and flavonoid content, along with antioxidant and antimicrobial activities. Solid-state fermentation, being environmentally friendly and cost-effective, is particularly suitable for agricultural residues. Significant increases (p < 0.05) in total polyphenol content (TPC), total flavonoid content (TFC), and antioxidant power were observed post-fermentation, especially under co-culture conditions. The highest TPC (12.98 ± 0.29 mg GA/g) and TFC (1.83 ± 0.07 mg QE/g) were recorded in the co-culture fermentation of by-products from the Mozafati and Sayer varieties, respectively. HPLC analysis revealed changes in polyphenol profiles post-fermentation, with reductions in gallic and ferulic acids and increases in caffeic acid, p-coumaric acid, rutin, quercetin, and kaempferol. FT-IR analysis confirmed significant alterations in polyphenolic functional groups. Enhanced antimicrobial activity was also observed, with inhibition zones ranging from 8.26 ± 0.06 mm for Kabkab to 17.73 ± 0.09 mm for Mozafati. These results suggest that co-culture solid-state fermentation is a promising strategy for valorizing date by-products, with potential applications in nutraceuticals and/or pharmaceutical products and as valuable additives in the food industry.

A novel nanovoltammetric sensor design for the sensitive determination of caffeic acid in Turkish coffee

Caffeic acid has anti-inflammatory, antibacterial, anticarcinogenic and immunomodulatory properties as well as antioxidant properties. Therefore, precise determination of the quantity of this acid is important for analytical and therapeutic interests as well as for the safety and quality of food samples. This study aims to determine the amount of caffeic acid in Turkish coffee by using the square wave voltammetry technique. This method has been successfully applied for the precise determination of caffeic acid with a platform in which the glassy carbon electrode is constructed with a modifier obtained based on the synergistic effect of functionalized multi-walled carbon nanotubes with boron oxide nanoparticles. The proposed platform and method gave a quantification limit of 0.04 nM in a dynamic range of 1.0 nM ˗ 40 μM for caffeic acid and was successfully used in the Turkish coffee sample to determine caffeic acid. In addition, the results are found in line with the results obtained by UV-Vis spectrophotometry method, and the good recovery values also imply the feasibility of the platform for practical application.

Effects of Caffeine, Zinc, and Their Combined Treatments on the Growth, Yield, Mineral Elements, and Polyphenols of Solanum lycopersicum L.

(1) Background: The effects of Zn and caffeine as promoters of fruit quality in the Solanum lycopersicum L. cultivar 'Panarea' were tested. (2) Methods: During the 56 days of the experiment, plants were treated weekly with 100 mL of 1 mM Zn (Zn), 1 mg L-1 caffeine trimethyl-13C (caffeine), and 1 mM Zn + 1 mg L-1 caffeine trimethyl-13C (Zn + caffeine) and compared to plants that were given tap water (control). (3) Results: Caffeine was taken up by the roots and translocated to the leaves, which positively influenced the number of fruits per plant. After 56 days of treatment, Zn induced a positive increase in tomato dry weight, reducing shoot length (-16.7%) compared to the other treatments. Zn + caffeine had a positive effect on the phenylpropanoid pathway of fruits, and 4-coumaric acid, caffeic acid, and t-ferulic acid were significantly increased, as well as the total antioxidant capacity of the tomatoes. In the flavonoid pathway, only apigenin and luteolin contents were reduced by treatments. The tomatoes showed similar concentrations of the mineral elements Cu, Mn, Fe, Na, Ca, Mg, and K. The Zn and caffeine target hazard quotients were <1, indicating that health risks via the consumption of these tomatoes did not occur. (4) Conclusions: Tomato plants could be irrigated with water containing lower values of Zn, caffeine, and a combination of the two. The treated fruits are rich in antioxidant compounds, such as coumaric acid, caffeic acid, and t-ferulic acid, which are beneficial for human health. No considerable health risks associated with human consumption have been detected.

Phenolic Compounds, Fatty Acid Contents, and Antibacterial Properties of Ozonated and Non-Ozonated Tobacco Seed Oils

ABSTRACT In this study, the fatty acid content, phenolic compounds, and antimicrobial activity of seed oils from Ege Özbaş (EO), Sarıbağlar 407 (S407) and Akhisar 98 (A98) tobacco plants grown in the Aegean region were investigated. The ozonation process altered fatty acid and phenolic compound compositions and affected antimicrobial activities against Gram-positive and Gram-negative bacteria in the oils. Tobacco seed oils (TSOs) were extracted via cold pressing (CP) and Soxhlet extraction (SE). Fatty acids and phenolic compounds were analyzed using GC-FID and LC-MS/MS, respectively. Non-ozonated oils averaged 73% linoleic acid, 13% oleic acid, 9% palmitic acid, and 3% stearic acid, while ozonated oils contained 41% linoleic acid, 18% oleic acid, 22% palmitic acid, and 11% stearic acid. The presence of 33 phenolic compounds was investigated and 22 common phenolic compounds were detected in both ozonated and non-ozonated TSOs, including gallic acid, protocatechuic acid, chlorogenic acid, 3-hydroxybenzoic acid, (-)-epicatechin, 2,5-dihydroxybenzoic acid, caffeic acid, verbascoside, luteolin-7-glucoside, hesperidin, and rosmarinic acid. The increased antimicrobial activity of fatty acids and phenolic compounds following ozonation suggests the potential for developing creams to treat skin diseases and wounds caused by antibiotic-resistant pathogens, and to reduce the effects of aging skin wrinkles.

Identification of chemical constituents and pharmacokinetic characteristics of Xiaoyan Tuire Granule in rats

Xiaoyan Tuire Granule is a type of Chinese patent medicine that has been proven effective in treating respiratory tract infections. However, while it has been successfully introduced into clinical use, more knowledge is still needed regarding its chemical components and pharmacokinetics. This study investigated the chemical profile in the medicine and rat plasma by ultra high-performance liquid chromatography coupled with Q Exactive hybrid quadrupole-orbitrap high-resolution accurate mass spectrometry (UHPLC-Orbitrap-MS/MS). Subsequently, it developed a validated ultra high-performance liquid chromatography coupled with quadrupole mass spectrometry (UHPLC-MS/MS) method for determining five components in rat plasma after oral administration of Xiaoyan Tuire Granule. As a result, a total of 106 constituents were inferred, including 9 terpenoids, 29 flavonoids, 33 organic acids, 12 phenylpropanoids and 23 other compounds. After administration, 86 compounds were inferred in rat plasma, including 73 prototypes and 13 metabolites. The metabolic pathways were primarily hydrogenation, glucuronic acid conjugation, sulfate conjugation, hydrolysis and methylation. The established method determined the contents of esculetin, esculin, isovitexin, caffeic acid and p-coumaric acid had a good separation, and all the legal verification met the requirements. The pharmacokinetic results indicate that the absorption rate of the five compounds in vivo was rapid, with a Tmax of less than 0.25 h, and the elimination rate was also fast, with a half-time (T1/2) ranging from 1.22 h to 2.19 h. It is worth noting that esculin and esculetin have similar half-time in vivo due to their structural similarities. Among these five compounds, the AUC0-∞ and MRT0-∞ of p-coumaric acid and esculetin were relatively higher, indicating higher exposure and longer residence time of both compounds in vivo. In conclusion, this paper researched the chemical constituents and pharmacokinetics of Xiaoyan Tuire Granule, which provided the reference for further study.

Effect of polyphenolic dendrimers on biological and artificial lipid membranes

The use of dendrimers as nanovectors for nucleic acids or drugs requires the understanding of their interaction with biological membranes. This study investigates the impact of 1st generation polyphenolic carbosilane dendrimers on biological and model lipid membranes using several biophysical methods. While the increase in the z-average size of DMPC/DPPG liposomes correlated with the number of caffeic acid residues included in the dendrimer structure, dendrimers that contained polyethylene glycol chains generated lower zeta potential when interacting with a liposomal membrane. The increase in the fluorescence anisotropy of DPH and TMA-DPH probes incorporated into erythrocyte membranes predicted the ability of dendrimers to affect membrane fluidity in the hydrophobic interior and hydrophilic/polar region of a lipid bilayer. The presence of caffeic acid and polyethylene glycol chains in the dendrimer structure affected the thermodynamical properties of the membrane lipid matrix.

Cathodoluminescent and Characteristic X-Ray-Emissive Rare-Earth-Doped Core/Shell Protein Labels for Spectromicroscopic Analysis of Cell Surface Receptors.

Understanding the localization and the interactions of biomolecules at the nanoscale and in the cellular context remains challenging. Electron microscopy (EM), unlike light-based microscopy, gives access to the cellular ultrastructure yet results in grey-scale images and averts unambiguous (co-)localization of biomolecules. Multimodal nanoparticle-based protein labels for correlative cathodoluminescence electron microscopy (CCLEM) and energy-dispersive X-ray spectromicroscopy (EDX-SM) are presented. The single-particle STEM-cathodoluminescence (CL) and characteristic X-ray emissivity of sub-20 nm lanthanide-doped nanoparticles are exploited as unique spectral fingerprints for precise label localization and identification. To maximize the nanoparticle brightness, lanthanides are incorporated in a low-phonon host lattice and separated from the environment using a passivating shell. The core/shell nanoparticles are then functionalized with either folic (terbium-doped) or caffeic acid (europium-doped). Their potential for (protein-)labeling is successfully demonstrated using HeLa cells expressing different surface receptors that bind to folic or caffeic acid, respectively. Both particle populations show single-particle CL emission along with a distinctive energy-dispersive X-ray signal, with the latter enabling color-based localization of receptors within swift imaging times well below 2 min per 2 while offering high resolution with a pixel size of 2.78 nm. Taken together, these results open a route to multi-color labeling based on electronspectromicroscopy.

Evaluation of phytotoxic potential in Asteraceae plant extracts for biological control of Echinochloa crus-galli and Echinochloa colona.

This study evaluates the phytotoxic potential of methanolic extracts from six Asteraceae species: Wedelia chinensis, Helianthus annuus, Cosmos bipinnatus, Tagetes erecta, Tithonia diversifolia, and Zinnia elegans. The extracts were tested at concentrations of 0.03, 0.1, 0.3, and 1.0 g/mL to assess their inhibitory effects on the radicle and hypocotyl lengths of Echinochloa crus-galli and Echinochloa colona. The two most potent species, C. bipinnatus and T. diversifolia, were further evaluated using extracts from their roots, stems, and leaves. Among these, C. bipinnatus leaf extracts showed the most significant phytotoxicity and were tested at 20, 40, and 60 days of plant age. At 0.03 g/mL, C. bipinnatus extract inhibited the hypocotyl and radicle lengths of E. colona by 23.01% and 56.45%, and E. crus-galli by 8.5% and 36.35%, respectively. At 1.0 g/mL, the extract inhibited the hypocotyl lengths of E. colona and E. crus-galli by 97.54% and 88.15%, and the radicle lengths by 93.52% and 99.99%, respectively. The 60-day-old C. bipinnatus leaf extract exhibited the highest inhibitory effect, correlating with the identification of key allelochemicals such as cinnamic acid, caffeic acid, coumaric acid, ferulic acid, 2-4 dimethohydroxy benzoic acid, and salicylic acid. These findings suggest that the 60-day-old C. bipinnatus leaf extracts have strong potential for use in the biological control of these weed species, offering a promising avenue for the development of natural herbicides.

Mechanism of inhibition of alpha-amylase by caffeic acid using in-vitro and in-silico techniques

Type-two diabetes, characterised by insulin resistance or inadequate insulin production, is prevalent among adults. The α-amylase enzyme contributes to carbohydrate digestion, elevating postprandial glucose levels. Natural compounds like caffeic acid offer a solution. This study investigates α-amylase inhibition via in-vitro and in-silico methods, emphasising the connection between phenolic compounds and antidiabetic efficacy for in-silico analysis. Enzyme kinetics, IC50, and molecular docking examine caffeic acid’s inhibitory action on α-amylase, comparing it with gallic acid and acarbose. Caffeic acid outperforms acarbose with an IC50 of 4.505 mg/mL versus 16.81 mg/mL, showcasing strong antidiabetic activity. Caffeic acid’s superior 1,1-diphenyl-2-picrylhydrazyl (DPPH) inhibition (90.67%) compared to gallic acid (55.76%) indicates potent antioxidative and antidiabetic properties. Molecular docking reveals hydrogen bonding between caffeic acid and α-amylase. These insights lay the groundwork for phenolic-based diabetic therapies, offering less expensive treatment for diabetes patients.

Identification of pancreatin inhibitors from Thai medicinal Piper plants for antidiabetic and anti-obesity activities using high-performance thin-layer chromatography-bioautographic assay

Exploring the potential of natural products against diabetes and obesity is in demand nowadays. Pancreatic α-amylase and pancreatic lipase are the drug targets to minimize the absorption of glucose from starch and fatty acids from lipids, respectively. In this study, five Piper species, namely P. sarmentosum (Ps), P. wallichii (Pw), P. retrofractum (Pr), P. nigrum (Pn), and P. betle (Pb), which are commonly used as food ingredients and traditional medicines, were evaluated for their inhibitory activities against pancreatin using the microtiter plate method. Additionally, pancreatin inhibitors were identified through a cost-effective high-performance thin-layer chromatography (HPTLC)-bioautography developed using red starch and p-nitrophenyl palmitate, corresponding to anti-amylase and -lipase activities, respectively. Of the 15 samples tested, leaf samples from Pb, which had the highest total phenolic and total flavonoid contents, exhibited remarkable inhibitory activity against pancreatin, with a relative amylase inhibitory capacity (RAIC) ranging between 4.260 × 10−5 and 4.861 × 10−5 and a reciprocal half-maximal inhibitory concentration (1/IC50, PTL) of 0.390–0.510 (mg/mL)−1. Additionally, Ps samples demonstrated the second-ranked anti-pancreatin activity. Principal component analysis indicated that total phenolic content contributed to the anti-pancreatin activities of Pb samples. The anti-pancreatin bands were isolated and identified as caffeic acid, myricetin, genistein, piperine, and eugenol. Myricetin, in the roots of Ps samples, showed notable anti-pancreatin activity, which was consistent with results from the in silico prediction toward pancreatic α-amylase and pancreatic lipase. Caffeic acid and eugenol were present in Pb samples. In conclusion, the developed cost-effective pancreatin HPTLC-bioautography efficiently identified amylase and lipase inhibitors from Piper herbs, which supported the use of these plants for antidiabetes and anti-obesity.

Multi-omics analysis reveals associations between host gene expression, gut microbiota, and metabolites in chickens.

Egg-laying is an important trait in chickens, and it is affected by many factors, such as hormones regulated by the hypothalamic-pituitary axis and precursors synthesized by the liver. Recent studies showed that gut microbiota was associated with egg-laying, however, its underlying mechanism remains unclear. We comprehensively analyzed the host transcriptome, gut microbiota, and metabolome in broiler breeder hens during the pre-laying, peak-laying, and late-laying periods. The transcriptome analysis of the tissues related to the hypothalamic-pituitary-liver (HPL) axis revealed dynamic gene expression during egg-laying periods. Differentially expressed genes (DEGs) (i.e., PENK, NPY, AVP, PRL, RLN3, and FST) from the hypothalamus and pituitary gland were involved in female gonadal development, hormone secretion, response to endogenous stimulus, liver development, and amide metabolism. In liver, DEGs (i.e., FABP3, VTG1, LPL, APOA5, APOV1, and RBP5) were enriched in efferocytosis, sphingolipid metabolism, amide, and peptide biosynthesis. Alpha and beta diversity changed significantly in cecum microbiota during different laying periods. The abundance of Firmicutes was decreased and the abundance of Bacteroidota was increased during the peak-laying period. Functional analysis showed that the biosynthesis of secondary metabolites, amino acids, purine, and steroid hormones was altered during laying. The metabolome analysis from cecal contents showed that amino acid metabolism and steroid hormone biosynthesis changed during laying. Integrated analysis of the cecal microbiota and metabolites showed the genus Megasphaera was involved in amino acid metabolism, which included 3-phenyllatic acid, quinic acid, caffeic acid, and folic acid, and the genus Hungatella participated in steroid hormone biosynthesis through its strong correlation with estradiol. These results explored the dynamic changes in tissues related to the HPL axis and cecal microbiota and provided new insights into the interaction between the host and microbiota during egg-laying in chickens.

Assessment of the phenolic profile and biological activities of aqueous date seed extracts: A comparative analysis

Date palm fruit (Phoenix dactylifera L.) is a well-known fruit that has become increasingly popular among consumers due to its pleasant flavor, nutrient-dense content, and nutraceutical characteristics. Date seeds are the main by-product of date fruit consumption and processing. Date seeds are usually incorporated in animal feed; however, their application in human contexts, such as food products, remains minimal. Nonetheless, they contain significant amounts of bioactive phenolic compounds, primarily flavonoids, which possess potential health benefits. The current study investigated and compared the phenolic profile, antioxidant, and antibacterial activities of aqueous extracts of nine different date seeds varieties. The phenolic profile, analyzed using high-performance liquid chromatography (HPLC-DAD-ESI-MS), showed that total phenolic compounds ranged from 1.05 to 1.24 mg/g in Reziz and Naghal varieties, respectively, with flavan-3-ols predominating in all varieties. Results of the ABTS and DPPH assays revealed that the antioxidant activities against free radicals were directly correlated with the overall phenolic content, particularly for caffeic acid. Indeed, all date seeds possessed antibacterial capabilities, with a stronger effect observed on Listeria monocytogenes than Escherichia coli. Additionally, date seeds demonstrated a promising source of oil rich in oleic and lauric acids, both of which are considered beneficial for health. According to our findings, date seeds are a significant source of bioactive compounds, which renders them ideal candidates for potential inclusion in human diets as food additives and nutraceuticals.

Metabolic and biochemical analyses reveal heavy metals tolerance mechanisms in Amaranthus retroflexus L.

One of the most prevalent plant species in the contaminated area around a sewage dumping lake at Khulais (Jeddah, Saudi Arabia) in the Arabian desert eco-region was found to be Amaranthus retroflexus L. This plant has the capacity to bioaccumulate and bioremediate heavy metals. The current study, therefore, aimed at investigating the plant's defense mechanisms by conducting metabolic and biochemical assessments. To this end, A. retroflexus plants were collected from the sewage dumping lake of Khulais, across five sites at varying distances from the lake, each exhibiting different level of heavy metal. The results indicated an increase in antioxidant defense system emerged as a protection strategy for A. retroflexus plants against soil contaminations. This, for instance, included the increased synthesis of polyamines (e.g., putrescine, spermidine, and spermine by +9–63%), flavonoids (e.g., naringenin, kaempferol, luteolin, and rutin by +10–146%), and phenolic acids (e.g., chlorogenic acid, gallic acid, caffeic acid, p-coumaric acid, chicoric acid, rosmarinic acid, and protocatechuic acid), increased by 10–254%. Additionally, plants adjusted their metabolic processes by synthesizing various low molecular weight amino acids, including proline (+19–299%), phenylalanine (+98–240%), glutamate (+34–492%), arginine (+10–64%), and ornithine (+51–210%). The activity of the metabolic enzymes involved in metabolism of these amino acids was enhanced accordingly. It can be concluded that the synthesis of polyamines and amino acids can be coordinated and complemented to improve the tolerance of A. retroflexus to cope with heavy metal accumulation in contaminated soils.