Polyphenols Research Articles

A Tannin–Oxidized Glucose Wood Adhesive with High Performance

Tannin, as a natural polyphenol found in plant sources, has been widely employed to replace petrol-based phenol to prepare tannin-based wood adhesives. However, the development of all-biomass tannin-based wood adhesive with superior bonding strength and water resistance is still a challenge. Herein, an all-biomass tannin-based adhesive was synthesized using tannin and glucose, demonstrating enhanced bonding strength and water resistance. To improve the reactivity of glucose, part of the hydroxyl groups on the glucose molecule is oxidized to aldehyde groups. The successful oxidation of glucose and synthesis of tannin-oxidized glucose (TOG) adhesive were demonstrated by Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). It was suggested that the improvement of TOG adhesive bonding properties and water resistance were caused by the formation of cross-linked network with covalent and hydrogen bonding synergies. The TOG adhesive has good water-resistance, and its residual rates can reach to 93.8% after soaking in water for 24h while the residual rates of tannin-glucose (T-G) adhesive only 81%. Compared with T-G and TOG adhesives, the dry bonding strength of adhesive increased by 256.5%, from 0.62MPa to 2.21MPa, the wet bonding strength of adhesive from zero to 1.97MPa. The plywood prepared with TOG adhesive met the GB/T 17657-2022 standard for Class II plywood. This study introduces an innovative and eco-friendly method for synthesizing an all-biomass tannin- based wood adhesive, characterized by superior bonding strength and enhanced water resistance.

Development, characterization, and assessment of PLAROsomal vesicular system of curcumin for enhanced stability and therapeutic efficacy

Abstract Background Curcumin (CUR) is a natural polyphenol and one of the key phytoconstituents found in the rhizomes of Curcuma Longa. It exhibits various pharmacological properties, encompassing antioxidant, anticancer effects, antiseptic, and anti-inflammatory, among several others. A significant drawback of using CUR is its limited bioavailability, which primarily depends on gut microorganisms responsible for converting it into its bioavailable form. Therefore, the contemporary study intended to formulate a novel PLAROsomal vesicular delivery of CUR, i.e., CUR-PLAROsomes employing a design of experiments approach to examine the influence of various process parameters, such as particle size and drug percentage release. Result The prepared CUR-PLAROsomes were characterized for their physicochemical properties using various hyphenated tools. The CUR-PLAROsomes exhibited sizes ranging from 40 to 300 nm, and the optimized batch demonstrated a drug entrapment of 86.38 ± 0.22%. In-vitro anticancer studies were conducted using human colorectal adenocarcinoma cells (COLO320DM) and human breast adenocarcinoma (MCF-7). CUR-PLAROsomes exhibited significant in-vivo anti-inflammatory potential against carrageenan-induced paw edema. CUR-PLAROsomes were more potent against COLO320DM and MCF-7 cell lines, even at lower concentrations, than pure CUR. Conclusion Furthermore, based on the observations, it exhibits potential as an anti-inflammatory agent, suggesting that PLAROsomes are an effective vesicular drug delivery system. Highlights Newly introduced PLARosome is a next generation of Liposomes which have gain popularity owing to its better adaptability to overcome leakage problem of vesicular drug delivery system. This is the pioneer attempt to prepare Curcumin-loaded PLARosome as an anti-cancer and anti-inflammatory activity. Nano size of the PLAROsomes may contribute to enhance the efficacy of Curcumin as a target specific drug delivery system. Site specific delivery of phytoconstituents is possible by use of PLAROsomes as a novel drug delivery system. Graphical abstract

Natural Polyphenol‐Reinforced Ion‐Selective Separators for High‐Performance Lithium‐Sulfur Batteries with High Sulfur Loading and Lean Electrolyte

AbstractIon‐selective separators are promising to inhibit soluble intermediates shuttle in practical lithium‐sulfur (Li−S) batteries. However, designing and fabricating such high‐performance ion‐selective separators using cost‐effective, eco‐friendly, and versatile methods remains a formidable challenge. Here we present ion‐selective separators fabricated via the spontaneous deposition of green tea‐derived polyphenols onto a polypropylene separator, aimed at enhancing the stability of Li−S batteries. The resulting natural polyphenol‐reinforced ion‐selective (NPRIS24) separators exhibit rapid Li ion transport and high soluble intermediates inhibition capability with an ultralow shuttle rate of 0.67 % for Li2S4, 0.19 % for Li2S6 and 0.10 % for Li2S8. This superior ion‐selectivity arises from the high electronegativity and strong lithiophilic nature of the phenolic compounds. Consequently, we have achieved high‐performance Li−S batteries that are steadily cyclable under the challenging conditions of an S loading of 5.7 mg cm−2, an electrolyte‐to‐S ratio of 5.1 μL mg−1, and a 50 μm Li foil anode. Furthermore, the NPRIS24 separator enhances the performance of other Li metal batteries utilizing commercial LiFePO4 (5.3 mg cm−2) and LiNi0.5Co0.2Mn0.3O2 (9.9 mg cm−2) cathodes. This work underscores the potential of utilizing natural polyphenols for the design of advanced ion‐selective separators in energy storage systems.

Natural Polyphenol-Reinforced Ion-Selective Separators for High-Performance Lithium-Sulfur Batteries with High Sulfur Loading and Lean Electrolyte.

Ion-selective separators are promising to inhibit soluble intermediates shuttle in practical lithium-sulfur (Li-S) batteries. However, designing and fabricating such high-performance ion-selective separators using cost-effective, eco-friendly, and versatile methods remains a formidable challenge. Here we present ion-selective separators fabricated via the spontaneous deposition of green tea-derived polyphenols onto a polypropylene separator, aimed at enhancing the stability of Li-S batteries. The resulting natural polyphenol-reinforced ion-selective (NPRIS24) separators exhibit rapid Li ion transport and high soluble intermediates inhibition capability with an ultralow shuttle rate of 0.67 % for Li2S4, 0.19 % for Li2S6 and 0.10 % for Li2S8. This superior ion-selectivity arises from the high electronegativity and strong lithiophilic nature of the phenolic compounds. Consequently, we have achieved high-performance Li-S batteries that are steadily cyclable under the challenging conditions of an S loading of 5.7 mg cm-2, an electrolyte-to-S ratio of 5.1 μL mg-1, and a 50 μm Li foil anode. Furthermore, the NPRIS24 separator enhances the performance of other Li metal batteries utilizing commercial LiFePO4 (5.3 mg cm-2) and LiNi0.5Co0.2Mn0.3O2 (9.9 mg cm-2) cathodes. This work underscores the potential of utilizing natural polyphenols for the design of advanced ion-selective separators in energy storage systems.

Protective Effects of Isostrictiniin Against High-Fat, High-Sugar Diet-Induced Steatosis in MASLD Mice via Regulation of the AMPK/SREBP-1c/ACC Pathway

Objectives: Isostrictiniin (ITN), a natural polyphenol extracted from Nymphaea candida (snow-white waterlily), has antioxidant and hepatoprotective activities that may be beneficial in treating metabolic dysfunction-associated steatotic liver disease (MASLD). This study aimed to investigate the protective effects of ITN on high-fat, high-sugar diet (HFSD)-induced steatosis in MASLD mice and its mechanisms. Methods: Kunming mice were randomly divided into normal control and HFSD groups. After being fed for 4 weeks, the HFSD group was randomly divided into model, atorvastatin calcium (ATC; 10 mg/kg), and ITN (25, 50, and 100 mg/kg) groups. After continued feeding for 4 weeks, the biochemical indexes in the mice were determined. Results: Compared with the model group, the liver index; FBG; HOMA-IR; serum AST, ALT, TG, TC, and LDL-C; and liver MDA, IL-6, TNF-α, and IL-1β levels in the ITN (25, 50, and 100 mg/kg) and ATC (10 mg/kg) groups were significantly decreased (p < 0.05), while serum HDL-C and liver SOD and GSH-Px levels were increased (p < 0.05). Pathological observation showed that ITN treatment mitigated the lipid liver deposition in the HFSD mice. Moreover, ITN could upregulate liver-tissue p-AMPK/AMPK protein expression in the HFSD-induced MASLD mice and downregulate SREBP-1c and ACC levels (p < 0.05). Conclusions: ITN can significantly improve MASLD mice, and its mechanism may be related to the regulation of the AMPK/SREBP-1c/ACC pathway.

Harnessing curcumin and nanotechnology for enhanced treatment of breast cancer bone metastasis.

Breast cancer (BC) bone metastasis poses a significant clinical challenge due to its impact on patient prognosis and quality of life. Curcumin (CUR), a natural polyphenol compound found in turmeric, has shown potential in cancer therapy due to its anti-inflammatory, antioxidant, and anticancer properties. However, its metabolic instability and hydrophobicity have hindered its clinical applications, leading to a short plasma half-life, poor absorption, and low bioavailability. To enhance the drug-like properties of CUR, nanotechnology-based delivery strategies have been employed, utilizing polymeric, lipidic, and inorganic nanoparticles (NPs). These approaches have effectively overcome CUR's inherent limitations by enhancing its stability and cellular bioavailability both in vitro and in vivo. Moreover, targeting molecules with high selectivity towards bone metastasized breast cancer cells can be used for site specific delivery of curcumin. Alendronate (ALN), a bone-seeking bisphosphonate, is one such moiety with high selectivity towards bone and thus can be effectively used for targeted delivery of curcumin loaded nanocarriers. This review will detail the process of bone metastasis in BC, elucidate the mechanism of action of CUR, and assess the efficacy of nanotechnology-based strategies for CUR delivery. Specifically, it will focus on how these strategies enhance CUR's stability and improve targeted delivery approaches in the treatment of BC bone metastasis.

Curcumin Induces MCF-7 Breast Cancer Cell Apoptosis Through miR-15a Alteration

Background: In recent years, the application of herbal compounds in cancer treatment has shown significant progress. Curcumin (CUR), a natural polyphenol, demonstrates potent anti-cancer effects against various cancers, including breast cancer (BC). Curcumin targets a range of molecular pathways, contributing to the inhibition of cancer cell proliferation, metastasis, and angiogenesis, and promoting apoptosis. Objectives: This study aimed to assess the effect of CUR on BC cells, focusing on alterations in the expression levels of Mir-15a and Bcl-2 through the apoptotic pathway. Methods: The cytotoxicity of CUR was evaluated using an MTT assay. Changes in the expression of Mir-15a and Bcl-2 genes were analyzed by real-time PCR, and cell apoptosis was measured using flow cytometry. Data analysis was conducted using SPSS. Results: The MTT assay results indicated that cell viability decreased as CUR concentration increased (5 – 25 µM). Real-time PCR results showed a significant decrease in the expression of Mir-15a and Bcl-2 (P < 0.05). Flow cytometry findings demonstrated that CUR treatment at the IC50 concentration for 48 hours induced apoptosis in 75.9% of MCF-7 cells. Conclusions: Our study provides a crucial foundation indicating that CUR induces apoptosis in MCF-7 cells by modulating the expression of Mir-15a.

Polyphenolic Compounds Activate SERCA1a and Attenuate Methylglyoxal- and Palmitate-Induced Impairment in Pancreatic INS-1E Beta Cells

Sarco/endoplasmic reticulum Ca2+-ATPase (SERCA) is an important regulatory protein responsible for maintaining calcium homeostasis within cells. Impairment of SERCA associated with activity/expression decrease has been implicated in multiple chronic conditions, including cardiovascular diseases, diabetes, cancer, neurodegenerative diseases, and skeletal muscle pathologies. Natural polyphenols have been recognized to interact with several target proteins involving SERCA. To date, only a limited number of polyphenolic compounds or their derivatives have been described either to increase SERCA activity/expression directly or to affect Ca2+ signaling pathways. In this study, we tested polyphenols for their ability to activate SERCA1a in the absence or presence of methylglyoxal or palmitate and to impact insulin release in pancreatic beta cells. The protective effects of these compounds against methylglyoxal- or palmitate-induced injury were evaluated. Results indicate that 6-gingerol, resveratrol, and ellagic acid activate SERCA1a and protect against activity decrease induced by methylglyoxal and palmitate. Molecular docking analysis revealed the binding of these polyphenols to Glu439 in the SERCA1a P-domain, suggesting a critical role in the stimulation of enzyme activity. Ellagic acid was found to directly stimulate the activity of SERCA1a, marking the first instance of such an observation.

The Metabolic Characteristics and Bioavailability of Resveratrol Based on Metabolic Enzymes.

The natural polyphenol resveratrol (RV) has garnered fame for its extensive pharmacological properties. Although clinical studies have shown some positive results, many contradictory outcomes remain. An important obstacle to the development of therapeutic applications for RV is its low bioavailability in vivo. This may be partially attributed to biotransformation mediated by phase I and II enzymes, such as cytochrome P450s, UDP-glucuronosyltransferases, and sulfotransferases. To date, more than 20 different types of metabolites have been detected after catalysis by these enzymes. Notably, RV and some of its metabolites serve as substrates for these enzymes. Conversely, RV can directly regulate the expression or activity of these enzymes. Given the increasing number of studies investigating the bioactivity of RV, this review summarizes its physicochemical and pharmacokinetic characteristics and describes the metabolism of RV and the bioactivities of its metabolites, with emphasis on the interaction between RV and its related metabolic enzymes. In addition to hepatic metabolism, the crucial roles of RV metabolism in multiple other tissues and organs cannot be overlooked, and they reveal the relationship between RV metabolism and its biological potential.

Curcumin-Etoposide Synergy: Unveiling the Molecular Mechanisms of Enhanced Apoptosis and Chemoresistance Attenuation in Breast Cancer

Background: Combining natural compounds with chemotherapeutic agents has emerged as a promising approach for cancer treatment. Curcumin (Cur), a natural polyphenol, is known for its anti-cancer properties, including the ability to induce apoptosis and arrest cell cycle progression. Objectives: This study aimed to evaluate the effects of Cur and etoposide (ETO), both individually and in combination, on the induction of apoptosis in breast cancer (BC) cell lines. Methods: The impact of Cur and ETO on cell proliferation was assessed using MTT viability assays. Apoptosis induction by these drugs was evaluated through Annexin V flow cytometry and caspase-3 and caspase-9 activity assays. Quantitative real-time PCR was employed to measure Bax and Bcl-2 gene expression levels. Western blotting was conducted to determine protein levels of p53, p21, Bax, and Bcl-2. Results: A non-significant dose of ETO was selected based on MTT assay results and combined with 75 µM of Cur. Curcumin enhanced ETO’s pro-apoptotic effect by increasing caspase activities. The combination of Cur and ETO significantly reduced Bcl-2 gene expression while upregulating Bax expression. Furthermore, treatment with this combination elevated the protein levels of p53, p21, and Bax, compared to ETO or Cur alone, while significantly decreasing Bcl-2 protein levels. Conclusions: Cur has the potential to amplify ETO-induced apoptosis in BC cells. This combination may offer a promising therapeutic approach for BC.

Nanoenabled Self-Assembled Metal-Organic Algaecides Generated Photosynthetic Inhibition and Oxidative Stress for Sustainable Food Security.

Achieving food sustainability is one of the biggest challenges in the new millennium. Plant factory cultivation systems provide an alternative for food sustainability, while they often suffer from algal blooms. The overuse of conventional algaecides has caused significant environmental pollution and concerns about food security. Here, we design a nanoenabled metal-organic algaecide that is self-assembled from natural polyphenols and two functional metal ions for providing shading effects and delivering active ingredients synergistically to suppress algal blooms. Black wattle tannin (BWT) and Fe3+ ions are utilized to develop self-assembled FeBWT nanoalgaecides with significant shading effects for decreasing light transmission (up to 97 %) and effectively inhibiting algal photosynthesis. Further, the FeBWT is functionalized with Cu2+ ions (bimetallic Cu/FeBWT) to target the algal cells and release Cu2+ ions via phenolic-mediated cell surface interactions, thus enhancing the inhibition efficiency. Importantly, the biosafety of Cu/FeBWT is demonstrated through toxicity tests on zebrafish and NIH3T3 cells. In our real-world field test, the Cu/FeBWT demonstrates high algal inhibition performance (>95 %, over 30 days), and enhances the accumulation of food nutrients in model plant lettuces. Collectively, the supramolecular metal-organic nanoalgaecide provides a promise for nanoagrochemical application and promotes food sustainability and security.

Resveratrol Potentiates BCG-induced Trained Immunity in Human Monocytes.

Resveratrol is a natural polyphenol derived from plants such as grapes and berries. In addition to its role in plants during injury and infection, various cardioprotective, neuroprotective, and longevity-promoting effects were reported in diverse model organisms. The primary target of resveratrol is the deacetylase Sirtuin 1 (SIRT1), which regulates many immunological processes, including BCG-induced trained immunity response in humans. We, therefore, investigated the effect of resveratrol on trained immunity induced by BCG, β-glucan, C. albicans, or oxidized low-density lipoprotein (oxLDL). Using an in-vitro model of trained immunity with monocytes obtained from healthy donors, we demonstrate that resveratrol amplifies BCG-induced trained immunity regarding IL-6 and TNFα production after a secondary challenge. Although resveratrol did not improve and even limited glycolysis, oxidative phosphorylation, and reactive oxygen species production, it enhanced the permissive epigenetic mark H3K27Ac on IL-6 and TNFα promoters. In contrast to BCG-induced trained immunity, resveratrol potently inhibited training induced by β-glucan, C. albicans, oxLDL, and muramyl dipeptide (MDP), a peptidoglycan component of BCG. Resveratrol's unique boosting effect on BCG training depended on BCG being alive and metabolically active. These results suggest that resveratrol might amplify the effects of BCG vaccination, which should be mechanistically characterized further. In addition, resveratrol could alleviate oxLDL-induced training of innate immune cells in atherosclerosis, and in-vivo studies of trained immunity combined with resveratrol are warranted to explore these therapeutic possibilities.

Resveratrol Inhibits Nucleosome Binding and Catalytic Activity of PARP1

The natural polyphenol resveratrol is a biologically active compound that interacts with DNA and affects the activity of some nuclear enzymes. Its effect on the interaction between nucleosomes and poly(ADP-ribose) polymerase-1 (PARP1) and on the catalytic activity of PARP1 was studied using Western blotting, spectrophotometry, electrophoretic mobility shift assay, and single particle Förster resonance energy transfer microscopy. Resveratrol inhibited PARP1 activity at micro- and sub-micromolar concentrations, but the inhibitory effect decreased at higher concentrations due to the aggregation of the polyphenol. The inhibition of PARP1 by resveratrol was accompanied by its binding to the enzyme catalytic center and a subsequent decrease in PARP1 affinity to nucleosomal DNA. Concurrent binding of talazoparib to the substrate binding pocket of PARP1, which occurs in the presence of resveratrol, restores the interaction of PARP1 with nucleosomes, suggesting that the binding sites of resveratrol and talazoparib overlap. The data suggest that resveratrol can be classified as a natural inhibitor of PARP1.

A comprehensive review of structure-activity relationships and effect mechanisms of polyphenols on heterocyclic aromatic amines formation in thermal-processed food.

Heterocyclic aromatic amines (HAAs) are potent carcinogenic substances mainly generated in thermal-processed food. Natural polyphenols have been widely used for inhibiting the formation of HAAs, whereas the effect of natural polyphenols on HAAs formation is complex and the mechanisms are far from being clearly elucidated. In order to clarify the comprehensive effect of polyphenols on HAAs, this review focused on the structure-activity relationships and effect mechanisms of polyphenols on the formation of HAAs. In addition, the effects of polyphenols on HAAs toxicity were also first reviewed from cell, gene, protein, and animal aspects. An overview of the effect of polyphenol structures such as parent ring and exocyclic group on the mitigation of HAAs was emphasized, aiming to provide some valuable information for understanding their effect mechanism. The HAAs formation is inhibited by natural polyphenols in a dose-dependent manner largely through eliminating free radicals and binding precursors and intermediates. The inhibitory effect was probably affected by the quantity and position of hydroxyl groups in the aromatic rings, and polyphenols with m-hydroxyl group in the aromatic ring had the stronger inhibitory effect. However, the presence of other substituents and excessive hydroxyl groups in natural polyphenols might mitigate the inhibitory effect and even promote the formation of HAAs. This review can provide theoretical reference for effectively controlling the formation of HAAs in thermal-processed food by natural polyphenols and reducing their harm to human health.

Combination of Methotrexate and Resveratrol Reduces Pro-Inflammatory Chemokines in Human THP-1 Cells.

Methotrexate (MTX) is a widely used anti-metabolite drug in cancer therapy, but its efficacy is often hindered by reactive oxygen species (ROS)-induced cellular toxicity. Resveratrol, a natural polyphenol, possesses antioxidant and anticancer properties. Therefore, this in vitro study aimed to investigate the synergistic anti-proliferative and anti-inflammatory effects of MTX and resveratrol in human THP-1 cells. THP-1 cells were differentiated into macrophage-like cells using phorbol 12-myristate 13-acetate. In vitro experiments assessed the impact of various concentrations of MTX and resveratrol on cell viability and proliferation using the MTT assay. Concentration-effect curves were generated to elucidate their relationship. Gene expression was analyzed by RT-qPCR, while chemokine expression was measured via ELISA. Phagocytic and migratory activities were also evaluated. Differentiated THP-1 cells were treated with MTX and resveratrol and stimulated with dimethyl sulfoxide (DMSO) and lipopolysaccharide (LPS) as inflammatory stimuli. The combination of MTX and resveratrol exhibited an anti-proliferative effect in THP-1 cells (p = 0.03). The concentration-effect curve revealed IC50 values of 49.15 µg at 24hours (R = 0.8236) and 2.029e-005 µg at 48hours (R = 0.97) for MTX, and 20.17 µg at 48hours (R = 1.000) and 55.38 µg at 96hours (R = 0.9666) for resveratrol. Co-treatment with MTX and resveratrol significantly reduced mRNA and chemokine expression of CCL2, CCL3, CCL4, CCL5, and CXCL10 (p < 0.05). Moreover, decreased phagocytic and migratory activities were confirmed by phagocytosis and migration assays (p < 0.05). The combination of MTX and resveratrol effectively attenuated pro-inflammatory activity in THP-1 cells, as evidenced by the downregulation of mRNA and chemokine expression. These findings suggest that the synergistic effects of MTX and resveratrol hold promise for enhancing cancer therapeutics.

Polyphenols Modulate the miRNAs Expression that Involved in Glioblastoma.

Glioblastoma multiforme (GBM), a solid tumor that develops from astrocytes, is one of the most aggressive types of brain cancer. While there have been improvements in the efficacy of treating GBM, many problems remain, especially with traditional therapy methods. Therefore, recent studies have extensively focused on developing novel therapeutic agents for combating glioblastoma. Natural polyphenols have been studied for their potential as chemopreventive and chemotherapeutic agents due to their wide range of positive qualities, including antioxidant, antiinflammatory, cytotoxic, antineoplastic, and immunomodulatory activities. These natural compounds have been suggested to act via modulated various macromolecules within cells, including microRNAs (miRNAs), which play a crucial role in the molecular milieu. In this article, we focus on how polyphenols may inhibit tumor growth by influencing the expression of key miRNAs that regulate oncogenes and tumor suppressor genes.

Resveratrol plus carboxymethyl-β-glucan for children with respiratory diseases.

Respiratory infections in children, ranging from mild to severe, are a leading cause of school absences and medical visits, creating significant socio-economic burdens for families. Recent interest has focused on resveratrol, a natural polyphenol known for its antioxidant, anti-inflammatory, and antiviral properties. When combined with carboxymethyl-β-glucan (CM-glucan), a modified polysaccharide with immunostimulatory effects, this formulation has shown potential benefits in managing respiratory diseases.Our research examines five randomized clinical trials investigating the efficacy of resveratrol and CM-glucan nasal solutions in children. The trials included children with recurrent respiratory infections (RRIs) and allergic rhinitis. The results demonstrate significant reductions in key respiratory symptoms, including nasal congestion, sneezing, coughing, and fever. In addition to symptomatic relief, the treatment was associated with fewer medical visits, decreased medication use, and reduced school absences. Importantly, the combination also showed efficacy in decreasing wheezing episodes in non-atopic children with RRIs and improving symptoms of allergic rhinitis. While these findings are promising, the studies are limited by small sample sizes and short-term follow-up periods, raising questions about the long-term efficacy and safety of the treatment. Mild and transient nasal irritation was the only reported side effect. Based on these concepts, the combination of resveratrol and carboxymethyl-β-glucan could be considered a valuable add-on strategy, complementing standard pharmacological treatments for pediatric respiratory infections and allergic conditions.

Current Bioactive Compounds in the Treatment of Alzheimer's Disease

Abstract: Worldwide, more than 44 million individuals are living with Alzheimer's disease (AD), making it the most common type of dementia. Because neuroinflammation is so important in the development of AD, anti-inflammatory tactics may be a promising avenue for treatment. Searches were conducted in Scopus, the Web of Science, and PubMed using the following keywords: phytoconstituents, AD, traditional medicine, and Chinese herbs. Therefore, the purpose of this review was to summarise the known phytochemistry and current state of the chosen plant species. However, there has been limited effectiveness in clinical trials for AD with currently available anti-inflammatory medicines. This study brings together the latest findings in the treatment of AD using natural substances, specifically phytochemicals, which have anti-inflammatory, antioxidant, and neuroprotective characteristics. Although there has been little success with existing anti-inflammatory medications, there is hope for targeting molecular pathways associated with AD, including Aβ overproduction, apoptosis, oxidative stress, and mitochondrial dysfunction, through the use of natural bioactive chemicals such alkaloids, polyphenols, and terpenes. The promise of natural compounds as safer alternatives or supplementary therapies to current treatments for Alzheimer's disease is highlighted in this study, which focuses on their ability to alleviate major pathogenic processes in the disease. Their medicinal potential and effectiveness can be enhanced with additional research.

Investment casting of porous Mg-alloy networks biomechanically tuned for bone implant applications

Manufacturing technology has been refined and described for the fabrication of honeycomb-based bioresorbable networks for temporal bone replacement applications. Two novel techniques, digital light processing and investment casting, were utilized to produce customized, shape-optimized cellular constructs with additional orifices promoting tissue ingrowth during osteo-regeneration. For this purpose, a conventional magnesium casting alloy (AZ91) was chosen. Numerical simulations were conducted to predict the compressive behavior of the proposed biodegradable lightweight scaffolds. Spatial castings were adjusted to possess mechanical properties comparable to the ones of cortical or trabecular bones. Two kinds of protective coatings (plasma electrolytic oxidation and organic ones based on natural polyphenols from tea extract) were deposited and characterized. They can be utilized to control the degradation rate during exploitation to achieve a predictable implant lifespan. The elaborated layers aim to mitigate the rapid corrosion of magnesium substrates by prolonging their bioresorption time and thus expanding their applicability in osseointegration. To evaluate this assumption, immersion tests in phosphate-buffered saline were performed, showing better chemical resistance of PEO coating and as-cast sample (for both mass gain by below 1%), and visible increase in mass of sample coated with organic coating (increase by almost 5%). Compressive strength results from numerical approach were further validated by experimental compression tests, showing that PEO coating deteriorated compressive strength by almost 3%, and organic coating improved it by over 9%. Results achieved in numerical approach were better than expected for stiffer sample, and slightly lower for the one with bigger pores.

Comparison of the activity of theaflavins produced by recombinant polyphenol oxidase and commercial enzyme

Theaflavins (TFs) contribute greatly to the colour and flavor of black tea, and have various bioactivities beneficial to human health. This research compared the activity for enzymatic production of TFs from tea polyphenols by recombinant polyphenol oxidase (Malus domestica, GenBank login number LT718523.1, MdPPO2) versus commercial enzyme (Agaricus bisporus, AbPPO) in both free and immobilized form. It describes the difference in activity for TFs production between recombinant and natural polyphenol oxidase. Enzyme assays by LC-MS revealed that the TFs production by AbPPO was almost 5 times as high as recombinant MdPPO2 in free enzyme. When immobilized on mesoporous silica, the activity of recombinant MdPPO2 increased significantly, while AbPPO almost lost its activity. By comparing relative enzyme activity, the immobilization of recombinant MdPPO2 has the highest relative enzyme activity, which was above 6 times higher than free AbPPO. Among these TFs, TF3 was the most abundant, followed by TF2a, TF1 and TF2b.