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Sarcopenia is a progressive and generalized age-related skeletal muscle (SkM) disorder characterized by the accelerated loss of muscle mass (atrophy) and function. SkM atrophy is associated with increased incidence of falls, functional decline, frailty and mortality. In its early stage, SkM atrophy is associated with increased pro-inflammatory cytokine levels and proteasome-mediated protein degradation. These processes also link to the activation of atrophy associated factors and signaling pathways for which, there is a lack of approved pharmacotherapies. The objective of this study, was to characterize the capacity of the flavanol (+)-epicatechin (+Epi) to favorably modulate SkM mass and function in a rat model of aging induced sarcopenia and profile candidate mechanisms. Using 23 month old male Sprague-Dawley rats, an 8 weeks oral administration of the +Epi (1 mg per kg per day in water by gavage) was implemented while control rats only received water. SkM strength (grip), treadmill endurance, muscle mass, myofiber area, creatine kinase, lactate dehydrogenase, troponin, α-actin, tumor necrosis factor (TNF)-α and atrophy related endpoints (follistatin, myostatin, NFκB, MuRF 1, atrogin 1) were quantified in plasma and/or gastrocnemius. We also evaluated effects on insulin growth factor (IGF)-1 levels and downstream signaling (AKT/mTORC1). Treatment of aged rats with +Epi, led to significant increases in front paw grip strength, treadmill time and SkM mass vs. controls as well as beneficial changes in makers of myofiber integrity. Treatment significantly reversed adverse changes in plasma and/or SkM TNF-α, IGF-1, atrophy and protein synthesis related endpoints vs. controls. In conclusion, +Epi has the capacity to reverse sarcopenia associated detrimental changes in regulatory pathways leading to improved SkM mass and function. Given these results and its recognized safety and tolerance profile, +Epi warrants consideration for clinical trials.

Ag2O nanoparticle synthesis was carried out via co-precipitation technique based on using AgNO3 and secondary metabolites present in the aqueous extract of Opuntia humifusa fruit for the first time. The amount of measured total phenol, flavonoid content, flavone, and flavonol content, and anthocyanin were 38.46 μg eq gallic acid mg−1 extract, 8.34 μg eq quercetin mg−1 extract, 0.614 μg eq quercetin mg−1 DW, and 3.1 mmol L−1, respectively. Moreover, the predominant phenolic compound was gallic acid. Catechin and chlorogenic acid were found in both fruit juice and fruit aqueous extract. Scanning electron microscopy (SEM) of Ag2O-NPs showed the average particle size was 10.58 nm. Scanning electron microscopy, X-ray diffraction Spectroscopy, and UV/visible spectrometry also confirmed the synthesis. This study then focuses on IC50 and NO amount differences before and after the synthesis of Ag2O-NPs which were 448.29 and 101.38 μg mL−1 for IC50 and 35.7% and 62.6% for NO, respectively. [ABSTRACT FROM AUTHOR]

Sorbitol is an important primary metabolite that serves as both a carbon source and signal to pathogens. The leaf diseases caused by Alternata alternata are particularly serious in crabapple (Malus micromalus). Here, we found that sorbitol can enhance the resistance of crabapple to A. alternata R1 by increasing the content of flavonoid catechin. Nanomaterials as an emerging technology tool can efficiently deliver lncRNA to target cells. Here, we found nanoencapsulated lncRNA809 (SPc/lncRNA809) exhibits significant resistance to R1strain. To elucidate the effect of SPc/lncRNA809 on flavonoids catechin synthesis, we observed the expression of lncRNA809 was consistent with that of MmNAC17 which regulates the synthesis of catechin and both could jointly respond to sorbitol. MmNAC17 induced the accumulation of catechin in vivo by directly activating the expression of catechin synthase genes MmF3H and MmLAR. Correspondingly, overexpression of lncRNA809 significantly upregulated the expression of MmNAC17 and enhanced the disease resistance. This study reveals for the first time that sorbitol positively regulates the expression of MmNAC17 through lncRNA809, promoting the accumulation of catechin via the expression of MmF3H and MmLAR, ultimately improving the defense response of M. micromalus. This research provides a crucial foundation for the establishment and application of sorbitol-based signaling regulatory networks. [ABSTRACT FROM AUTHOR]

Lichuan black tea (LBT) is a well-known congou black tea in China, but there is relatively little research on its processing technology. Echa No. 10 is the main tea tree variety for producing LBT. This study investigated the sensory quality, flavor components, and bioactivity of Echa No. 10 Lichuan black tea (LBT) at different drying temperatures (70, 80, 90, 100, 110, 120, and 130 °C). During 80–120 °C, increasing the drying temperature enabled a higher sweet aroma concentration and enhanced the sweetness in the taste, in contrast to reducing the floral, fruity, and sweet aromas, and increasing the bitterness and astringency, at >120 °C. Additionally, with an increasing drying temperature, the contents of tea polyphenols and total catechins significantly decreased, with the theaflavins decreasing first and then increasing, and the alcohols, aldehydes, esters, and hydrocarbons increasing first and then decreasing. Meanwhile, compounds (including linalool, (Z)-linalool oxide (furanoid), (E)-linalool oxide (furanoid), cis-β-Ocimene, and methyl salicylate) contribute more to the floral and fruity aromas at <110 °C. Furthermore, low-temperature drying favors the antioxidant and inhibitory effects of the α-amylase, α-glucosidase, and glucose absorption activity. Both the tea quality and bioactivity results revealed 80–110 °C as the optimal drying temperature range for LBT. [ABSTRACT FROM AUTHOR]

Tea plants Camellia sinensis (L.) O. Kuntze consume substantial quantities of water and nutrients during the flowering period, which can adversely affect the yield and quality of tea plants. Therefore, the effects of thidiazuron, carbaryl, ethephon, and lime sulphur on flower buds and flower abscission in tea plants were investigated. The photosynthetic characteristics and biochemical components, the electrical conductivity of leaves, and the occurrence of insect pests and frost damage in the tea plants were assessed following the exogenous application of these chemicals. The results showed that 0.015, 0.03, and 0.06% thidiazuron, 0.08% ethephon, and 2.0 and 3.0% lime sulphur significantly promoted tea flower buds and flower abscission. Thidiazuron notably increased the concentrations of total amino acids, caffeine, catechin, and soluble sugar in tea leaves while reducing leaf electrical conductivity to some extent. Additionally, it also suppressed the occurrence of Empoasca onukii Matsuda (Hemiptera: Cicadellidae) and Apolygus lucorum Meyer-Dür (Hemiptera: Miridae). Furthermore, thidiazuron enhanced both the length and weight of tea shoots the following early spring. Application of 3.0% lime sulphur enhanced chlorophyll a and b, carotenoid, catechin, and caffeine and decreased the number of Aleurocanthus spiniferus Quaintanca (Hemiptera: Aleyrodidae) on the tea plants. However, no significant differences in frost damage were observed across treatments. Overall, exogenous application of the chemicals, particularly thidiazuron, effectively reduced flower production, altered key biochemical components, controlled tea pests, and ultimately enhanced tea productivity. [ABSTRACT FROM AUTHOR]

The promise of polymeric nanocomposite fibers in the biomedical field is well‐documented due to their adjustable properties and versatility. Electrospun fiber mats, which mimic the extracellular matrix, are particularly noted for their potential in tissue regeneration and repair. In this study, we investigate the role of catechin, a flavonoid, in enhancing cellular response to electrospun nanocomposite fibers of polycaprolactone (PCL), gelatin, and nanohydroxyapatite (nHA). Nanocomposite fibers were fabricated with varying concentrations of catechin and comprehensive analyses of the composite fibers were performed to evaluate their structural and chemical properties. In vitro, assays were performed to examine cell viability and ascertain the influence of catechin on cellular responses to these nanocomposite fibers. Simultaneously, in vivo studies assessed tissue responses to these materials. The findings revealed that incorporating catechin into PCL/gelatin/nHA nanocomposite fibers improved cellular responses in vitro as demonstrated by enhanced cell viability. Furthermore, in vivo investigations displayed positive tissue responses with these fibers, indicating their capacity to enhance cell growth and accelerate tissue regeneration. This study elucidates the potential of catechin as an integral component in designing polymeric nanocomposite fibers, potentially broadening the scope of their biomedical applications. [ABSTRACT FROM AUTHOR]

Objectives: Berlinia confusa is used as wound healing agent in folklore medicine. However, this has not been scientifically validated and there is dearth of information on its bioactive metabolites. The current research aimed at evaluating the wound healing, antioxidant and antimicrobial activities of the stem bark of the plant and track down some of its metabolites. Methods: The dermal excision model in Sprague Dawley rats was used for the in vivo wound healing activity of the 70% ethanol extract (formulated as 1% and 2% cream). The DPPH radical scavenging and in-vivo lipid peroxidation assays were used to assess the antioxidant activity whereas the agar well and broth-dilution assays were used for the antimicrobial activity evaluation. The PrestoBlue cell viability in keratinocytes and acute dermal toxicity assays were used for the safety assessment. Results: The 1% w/w extract showed over 70% wound surface closure from day 13-23 whereas the 2% w/w exhibited similar effect from day 15-23. The activity of the extract was comparable to 1% silver sulphadiazine (SSD) used as reference agent. The extract (1% w/w) also significantly reduced malondialdehyde (MDA) levels (455.2 ± 11.91) compared to the negative control group (739.8 ± 44.93) and was also superior to silver sulphadiazine (MDA level 548.4 ± 10.73). The extract again showed a considerable antimicrobial activity against pathogenic microorganisms with MIC's in the range of 5-10 mg/mL. The 2% extract did not show any skin irritation and were mildly toxic (88.2 ± 3.76% viability) to keratinocytes. Purification of the extract yielded two (2) major known wound healing metabolites including betulinic acid and catechin. Conclusion: Berlinia confusa has demonstrated considerable wound healing in vivo and also mitigated healing modifying factors such as microbes and reactive oxygen species. [ABSTRACT FROM AUTHOR]

Garlic (Allium sativum L.) is one of the oldest known useful plants, valued for thousands of years. This plant contains many biologically active compounds, including polyphenols, sterols, cysteine-sulfoxides, carbohydrates, proteins, and amino acids. The aim of our study was to compare the antioxidant potential, cytotoxicity, and apoptosis induction properties of four garlic cultivars—Harnaś, Ornak, Violeta, and Morado—in human squamous carcinoma (SCC-15) cells, colon adenocarcinoma (CACO-2) cells, and normal fibroblasts (BJ). Additionally, we investigated the mRNA and protein expression of peroxisome proliferator-activated receptor gamma (PPARγ), microtubule-associated protein 1 light chain 3 (LC3A), superoxide dismutase 1 (SOD1), and catalase (CAT) after treatment with the studied garlic extracts. Our study demonstrated that high ROS production was correlated with the strong toxicity of the garlic extracts. All studied extracts produced a lesser increase in ROS in normal BJ fibroblasts and were less toxic to these cells. The expression patterns of PPARγ, LC3A, SOD1, and CAT, along with chromatographic analysis, suggest differing mechanisms among the garlic cultivars. The highest levels of catechin, a known PPARγ agonist, were detected in the Harnaś (3.892 µg/mL) and Ornak (3.189 µg/mL) cultivars. A high catechin content was correlated with similar changes in PPARγ and related SOD1 and LC3A. Our findings showed the health-promoting and anticancer properties of garlic. However, we could not definitively identify which polyphenol or how it is involved in PPARγ activation. Further studies are required to elucidate the role of PPARγ in the mechanism of action of garlic extracts. [ABSTRACT FROM AUTHOR]

[Display omitted] • Quercetin (Q) and catechin (C) acted cooperatively against oxidative damage. • Q and C jointly ameliorated oxidative stress-induced acute alcoholic liver injury. • Q and C inhibited IKK α /p53 signaling via NF- κ B-independent pathway. • FOXO3 promoted IKK α transcription by binding to the IKK α promoter region. • Q and C suppressed IKK α transcription by attaching directly to FOXO3. Oxidative stress is one of the major contributors to acute alcoholic liver injury (AALI), which is a common alcoholic liver disease. Quercetin and catechin are flavonoid antioxidants present in plant foods and possess chemopreventive and chemotherapeutic activities. Quercetin and catechin are often included in the same meal and ingested together. While they show cooperative actions against oxidative damage, the underlying mechanisms behind their counteracting effects against oxidative stress-induced AALI remain poorly understood. The aim of this study was to understand the mechanism underlying the enhanced antioxidant effect of quercetin-catechin combination to alleviate AALI in rats. The ethanol (EtOH)-treated rats and H 2 O 2 -treated liver cells were used to demonstrate the enhanced antioxidant effect of quercetin and catechin. Then we used RNA-sequencing to compare quercetin alone, catechin alone and quercetin-catechin combination and then identified the critical role of IKK α combining with gene silencing and overexpression techniques. Its transcription factor, FOXO3 was found through yeast one-hybrid assay, luciferase reporter assay, EMSA and ChIP assay. Finally, the interaction between quercetin, catechin and FOXO3 was verified through molecular docking, UV–Vis absorption spectroscopy, fluorescence spectroscopy, and CD spectroscopy. The study demonstrated the enhanced antioxidant effect of a quercetin-catechin combination in EtOH-treated rats and in H 2 O 2 -treated liver cells. Quercetin and catechin cooperatively inhibited IKK α /p53 pathway and activated Nrf2 signaling pathway. IKK α was a critical negative regulator in their joint action. FOXO3 bound to IKK α promoter to regulate IKK α transcription. Quercetin and catechin influenced FOXO3-IKK α binding through attaching directly to FOXO3 at different sites and altering FOXO3′s secondary structures. Our study revealed the mechanism of quercetin and catechin against oxidative stress-induced AALI through jointly interacting with transcription factor. This research opens new vistas for examining the joint effect of therapeutics towards functional proteins and confirms the chemopreventive effects of multiple flavonoids via co-regulation. [ABSTRACT FROM AUTHOR]

GO/Co-MOF/PPy-350 (GPC-350) was synthesized by in situ growth of ultrafine Co-MOF on graphene oxide (GO), followed by encapsulation with polypyrrole (PPy) and calcination at 350.0℃. Meanwhile, MoS2-MWCNTs (MoS2-CNTs) were produced via the in situ synthesis of MoS2 within multi-walled carbon nanotubes (MWCNTs). The electrochemically superior GPC-350/MoS2-CNTs nanocomposite was then achieved by combining GPC-350 with MoS2-CNTs. The polypyrrole encapsulation serves to protect the ultrafine Co-MOF, preventing its degradation during the calcination process. The linear detection range of the GPC-350/MoS2-CNTs/GCE sensor for the determination of catechin (CA) in phosphate buffered saline (PBS) was from 5.0 to 1800.0 nM with a limit of detection of 1.78 nM. In addition, the materials were characterized using SEM, EDX, TEM, XRD, EIS, XPS, FTIR, and Raman. These results indicate that the synthesis of GPC-350/MoS2-CNTs nanocomposites is successful and CA in beverages samples can be effectively detected using electrochemical sensors. Additionally, the reaction mechanism of CA was explored through cyclic voltammetry. The application of GPC-350/MoS2-CNTs nanocomposites in sensor technology offers innovative approaches for the ultrasensitive detection of flavonoids. [ABSTRACT FROM AUTHOR]

This study evaluated the color change (ΔE00) and penetration depth (PD) of white spot lesions (WSLs) infiltrated with the resin infiltrant (Icon®) functionalized with methacrylate epigallocatechin-3-gallate (EGCG). To introduce polymerizable double bonds, EGCG was reacted with methacryloyl chloride (EM). Subsequently, the Icon resin infiltrant (I) was loaded with neat EGCG (IE) or EGCG–methacrylate (IEM) at 2 wt% each. WSLs were created on bovine enamel blocks and treated with I, IE, or IEM. Sound and untreated enamel surfaces were used as controls (C). Infiltrant PD (%) was determined by Confocal Laser Scanning Microscopy (CLSM, n = 12) analysis. For color change (ΔE00) determination (n = 14), ΔL, Δa, and Δb, half of each sample was kept sound as a reference area. The color was determined with a spectrophotometer. Data were statistically evaluated (p = 0.05). Surface morphology was obtained as a qualitative response variable using 3D CLSM. PD (%) did not differ statistically for I, IE, and IEM (p = 0.780). Groups I and IEM showed similar performance on color change (ΔE00) compared to the control group, while IE exhibited intermediate results, with no significant difference observed between the untreated, I, and IEM groups (p < 0.001). IEM promoted the masking of the WSL color without interfering with the PD. [ABSTRACT FROM AUTHOR]

The gallated catechin content in Wuyi Rock Tea is higher in the summer, leading to a more bitter and less desirable taste. Here, tannase, tyrosinase, and laccase were used to treat summer Rougui Wuyi Rock Tea extracts. The effects of single and combined enzymes on the taste of the tea extracts and their mechanisms of action were analyzed. Compared with the no-enzyme-treated sample, the sensory score results showed that tannase was the most effective, increasing the bitterness and astringency scores by 113.9% and 255.3%, respectively. Among the combined enzyme treatments, the samples treated with tannase and tyrosinase yielded the best sensory scores, with bitterness and astringency scores increasing by 141.2% and 289.0%, respectively. Data obtained using an electronic tongue confirmed the role of these enzymes, showing that, in addition to bitterness and astringency, enzyme treatment also influenced the bitterness aftertaste and astringency aftertaste, as well as its sourness and sweetness. Further product analysis revealed that tannase hydrolyzes the ester bonds on the gallacyl groups in gallated catechins, converting them to non-gallated catechins, while tyrosinase and laccase oxidize the phenolic hydroxyl groups on catechins to form o-quinone, leading to the production of theaflavins and improved tea quality. This study presents an effective approach to improving the quality of summer tea using biological enzymes. [ABSTRACT FROM AUTHOR]

The aim of the study was to assess the effect of fruit additives on the health-promoting properties of tea infusions. Black and white tea infusions enriched with fruit additives (lemon, quince, strawberry, and sweet pepper) were investigated. To assess the effect of the additives on the properties of the infusions, the content of phenols, antiradical activity, and reducing properties were analysed. The LC-QTOF-MS method facilitated the identification of catechins and the determination of their content. The principal component analysis was used to define the relationship between catechins and the health-promoting properties of the beverages. The research proved that the strawberry and sweet pepper additives improved the quality of the black tea, where the highest antiradical and antioxidant activity was noted. In turn, the additives used for the enrichment of the white tea had a negative effect on its health-promoting properties. The statistical analyses revealed that epicatechin gallate and epicatechin had the greatest impact on the antioxidant properties of the black tea and the white tea, respectively. [ABSTRACT FROM AUTHOR]

This work investigated the binding interaction between (+)-catechin (CC) and rice bran protein isolate (RBPI) by determining the structure and function. The binding methods were covalent and non-covalent with different CC concentrations (0.05, 0.15, and 0.25%). Compared with non-covalent interactions, CC was more likely to form covalent interactions with RBPI. Additionally, the oligomers were formed during the covalent interactions of protein to CC. The results showed that CC reduced the ɑ-helices and β-sheets of the protein, and increased β-turns and random coils. The content of SH group contents decreased with the increase of CC concentration. Since in the covalent interactions at pH 9.0, the negatively charged quinonoid forms of CC will neutralize the positively charged protein, so the absolute ζ-potential will increase. The covalently linked RBPI-CC complexes have a smaller particle size. It can be seen from the microscopic image that the protein forms become more granular through the covalent action of CC. In this contribution functional properties were obtained by emulsifying activity index (EAI), emulsifying stability index (ESI), water holding capacity (WHC) and fat holding capacity (FHC). The WHC and FHC exhibited noticeable improvement, especially when the covalent interactions concentration of CC was 0.15%. Additionally, CC effectively increased the antioxidant activity of RBPI. This study is advantageous to elucidate the mechanisms underlying the interactions of CC with RBPI and the possible uses of RBPI-CC complexes in food formulations. [ABSTRACT FROM AUTHOR]

Plants of the genus Atraphaxis have been widely used as traditional herbal medicines and are just beginning to be recognized for their pharmacological activities by scientific validation. In particular, Atraphaxis virgata (Regel) Krasn. has not reported even fundamental data, such as antioxidant activity and phytochemical properties, which requires investigation for its medical application. In this study, phytochemical compounds of A. virgata extracts were identified using high-performance liquid chromatography (HPLC) and gas chromatography–mass spectrometry (GC-MS) and their antioxidant activity was evaluated. As a result, A. virgata extracts were analyzed using HPLC and found to contain hesperidin 13.18 mg/g-extract, rutin 4.49 mg/g-extract, catechin 3.23 mg/g-extract, gallic acid 2.93 mg/g-extract, epicatechin-3-gallate 1.28 mg/g-extract, kaempferol 0.26 mg/g-extract, and luteolin 0.09 mg/g-extract. Furthermore, GC-MS analysis detected nine compounds (e.g., lup-20(29)-en-3-one and decane) in the extracts, which were reported to have various biological activities. The ABTS IC50, DPPH IC50, and FRAP values of A. virgata extracts were determined to be 126.57 ± 0.24 μg/mL, 42.17 ± 1.14 μg/mL, and 122.59 ± 8.79 mmol/L, respectively. This study is the first to report the antioxidant activity of A. virgata, suggesting its potential as a functional food or medicinal material. [ABSTRACT FROM AUTHOR]

SUMMARY: Galloylated catechins in tea leaves, primarily epigallocatechin‐3‐gallate (EGCG) and epicatechin gallate (ECG), possess prominent biological activities. It is well established that EGCG and ECG are abundantly present in tender leaves but are less prevalent in mature leaves. However, the fundamental regulatory mechanisms underlying this distribution remain unknown. In this study, we integrated transcriptome data and catechin component levels in tea leaves from six leaf positions using weighted gene co‐expression network analysis. This analysis revealed a positive correlation between variations in CsWRKY12 expression and EGCG and ECG levels. Further investigation using yeast one‐hybrid and dual‐luciferase assays, as well as electrophoretic mobility shift assay, demonstrated that CsWRKY12 activated the transcription of CsSCPL4 and CsSCPL5, which encode enzymes responsible for galloylated catechins biosynthesis, by directly binding to W‐box elements in their promoters. Overexpression of CsWRKY12 in tea leaves promoted the expression of CsSCPL4 and CsSCPL5, leading to an increase in EGCG and ECG content. Moreover, we found that a VQ motif‐containing protein, CsVQ4L, interacted with CsWRKY12 and facilitated its transcriptional function by regulating the expression of CsSCPL4 and CsSCPL5. Collectively, our findings suggest that the interaction between CsWRKY12 and CsVQ4L contributes to the accumulation of galloylated catechins in tender leaves of tea plants. Significance Statement: Galloylated catechins confer tea with flavor and health benefits and are abundant in tender leaves of tea plants. However, the regulatory mechanisms underlying this distribution remain unknown. Here, we uncovered that CsWRKY12 interacts with CsVQ4L to synergistically promote the substantial accumulation of galloylated catechins in the tender leaves of tea plants by directly activating the expression of CsSCPL4 and CsSCPL5, thereby providing potential gene resources for the genetic improvement of tea plant properties. [ABSTRACT FROM AUTHOR]

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Tea polyphenols have been reported to decrease the rate of starch hydrolysis by inhibiting α-glucosidase. However, the effect of the tea harvesting season and the structure of catechin monomers on the inhibitory activity of α-glucosidase is not understood. In this study, the inhibitory effect and underlying mechanism of four seasons of Dancong tea against α-glucosidase were investigated by in vivo and in vitro experiments, multi-spectroscope and molecular dynamic. The Dancong tea harvested in spring and winter showed a stronger inhibitory effect on α-glucosidase due to a higher content of catechin, especially EGCG ((-)-epigallocatechin-3-gallate). The results of in vivo and in vitro experiments showed that EGCG and ECG ((-)-epicatechin-3-gallate) with a higher content of gallate and hydroxyl groups exhibited a stronger inhibitory effect on starch hydrolysis, rise of postprandial blood glucose and activities of α-glucosidase compared to EGC ((-)-epigallocatechin) and EC ((-)-epicatechin). These gallate and hydroxy groups were more effective in interacting with the amino acid residues in the active site of α-glucosidase, leading to structural changes in the enzyme. Certainly, the inhibitory effect of Dancong tea on α-glucosidase explains one of the mechanisms by which it helps alleviate diabetes; the other hypoglycaemic mechanisms of Dancong tea will be further explored. [ABSTRACT FROM AUTHOR]

We found that cis-type gallated and non-gallated catechins form low water solubility outer-surface adducts with cucurbit[7]uril in aqueous solution, with cis-type gallated catechins showing a higher tendency to precipitate as outer-surface adducts. By exploiting this phenomenon, we achieved the selective separation of cis-type gallated and non-gallated catechins in solution. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSIONS Currently, protein–polyphenol complexes have garnered increasing attention as surface‐active substances in high internal phase Pickering emulsions (HIPPEs). However, the effects of the oil type and flavonoid structure on the HIPPE‐stabilizing ability of protein–polyphenol complexes remain unclear. Notably, very few studies have investigated the impacts and mechanisms of different oils (olive, flaxseed, and coconut oils) and the effects of the addition of flavonoids (catechin and quercetin) on the interfacial behavior of walnut protein hydrolysates (WPHs) and the co‐oxidation of protein‐lipid in the resulting emulsion during storage.Incorporating flavonoids was found to reduce the particle size and enhance WPH emulsification efficiency. Compared with catechin, quercetin demonstrated a greater affinity for adsorption at the oil–water interface, thereby improving the interfacial adsorption properties of WPHs across all the oil phases, although the oil type influenced the concentration of flavonoids at the interface. Excessive WPH–quercetin complex nanoparticles can form a dense multilayer at the interface and compactly pack oil droplets, endowing HIPPEs with higher viscoelasticity, greater storage stability, and stronger protection against lipid and protein oxidation than other WPH‐based HIPPEs do, especially in cases of olive oil–HIPPEs.Our results demonstrated that the interfacial structure of WPH–flavonoid complexes play a major role in the emulsion stabilization efficiency, followed by the type of oil. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Nanoemulsions are emulsions, either O/W (oil in water) or W/O (water in oil), with droplet diameters typically ranging from 50 to 1,000 nm. Research indicates that nanoemulsions are highly effective in enhancing the bioavailability, bioactivity, digestibility, stability, safety, quality and sensory attributes of food components. The study aimed to determine the optimum formulation and ultrasonic condition for fabricating catechin nanoemulsion (Ca-NE) from green tea with improved physical stability and antioxidant activity using response surface methodology. The effects of Medium Chain Triglyceride oil concentration (7.5 - 12.5 % w/w), Tween® 80 concentration (1 - 5 % w/w) and sonication time (5 - 15 min) on the droplet size, polydispersity index (PDI) and antioxidant activity presented by DPPH value of the Ca-NE were investigated using Box-Behnken design (BBD). The results found that droplet size and antioxidant activity of the Ca-NE were significantly (p < 0.05) affected by the proposed parameters, whereas the PDI value was slightly affected by those factors. The BBD results suggested that the Ca-NE fabrication condition was optimized with 7.5 % (w/w) oil concentration, 5 % (w/w) Tween® 80 concentration and a sonication time of 10.87 min. The optimum nanoemulsion showed good physical stability in terms of droplet size and PDI and had higher antioxidant activity than unencapsulated catechins when stored at 4 and 30 °C for 90 days. This study showed that catechin nanoemulsions fabricated by ultrasonication had good stability and antioxidant activity and, hence, had high potential for food and beverage applications in the food industry. [ABSTRACT FROM AUTHOR]

Used for over 4000 years as a therapeutic drink in China, tea has spread rapidly throughout the world. Prepared from Camellia sinensis leaves in three main forms – green, black and Oolong, the tea is rich in flavonoids, catechins, enzymes and methylxanthines. Caffeine is responsible for the energizing effect but also for certain side effects. Flavonoids and polyphenols are the chemical compounds that benefit from clinical trials which provide evidence of effects in cancer prevention or benefits in metabolic and cardiovascular diseases. This article reviews issues related to the history of tea use, its chemical composition, its relationship with metabolic diseases, and its role in cancer prevention. [ABSTRACT FROM AUTHOR]

Background: Cocoa powder derived from the Theobroma cacao plant is rich in polyphenols, such as catechin and epicatechin. These polyphenols are strong antioxidants when consumed orally; however, their ability to enter the stratum corneum following the topical application has never been demonstrated. Objective: The objective of this study was to demonstrate the deposition of catechin and epicatechin in the stratum corneum following the topical application of 6% aqueous cocoa powder 1 and 2 h after application. Methods: Five healthy female subjects aged 25–60 years were enrolled. A 6% aqueous cocoa powder solution was prepared and applied to two randomized designated spots on the left forearm. 2 cc of the solution was applied under a ¼‐inch gauze square covered with plastic wrap and held in place with a Coban dressing. The 15 d‐squame 7/8‐inch circular tape strips were applied to the predetermined area on the forearm 1 h and 2 h after application of the 6% cocoa powder solution. The tape strips were immediately placed in a −80°C freezer for storage until extraction in preparation for LC–MS evaluation for catechin and epicatechin levels. Results: More catechin and epicatechin were detected at 2 h than 1 h for both compounds, although the difference was not statistically significant. Higher epicatechin levels than catechin levels were detected from the cocoa powder at both time points. This is consistent with published data from food‐grade cocoa powder. Summary: It is detected that 6% aqueous cocoa powder delivers the antioxidants catechin and epicatechin to the stratum corneum 1 h and 2 h after topical application. [ABSTRACT FROM AUTHOR]

Simple Summary: Plant defense mechanisms can be divided into two categories: structural and chemical. Using morphological and biochemical analysis methods, we investigated the effect of the larch wooly adelgid Adelges laricis Vallot infestation on its secondary host, the European larch Larix decidua Mill. The population of the larch wooly adelgid developed from the end of April until the end of June, with the peak number in the first days of May. Anatomical examination of larch needles revealed the altered shape of the needles, the presence of a thicker layer of wax covering the epidermis and an increase in the number of layers of mesophyll as the results of adelgid feeding. The increased amounts of total phenols and individual flavonoids in adelgid-infested needles corresponded with the increase in the larch wooly adelgid numbers. The most abundant flavonoids were catechin and epicatechin, which predominated in larch needles collected at successive phases of adelgid infestation and their content increased along the increase in adelgid infestation. In contrast, the content of kaempferol decreased. These results greatly expand the knowledge on the anatomical and biochemical mechanisms of adelgid-conifer interaction. The study was carried out to assess the effect of the larch wooly adelgid Adelges laricis Vallot (Hemiptera: Adelgidae) infestation on its secondary host, the European larch Larix decidua Mill. Morphology and anatomy of adelgid-infested needles, and content of defense phenolic compounds including individual flavonoids isorhamnetin, kaempferol, quercetin, rutin, catechin, epicatechin, apigenin, ampelopsin and taxifolin, were analyzed. The amount of total phenols in needles from adelgid-infested twigs of L. decidua increased following the development of the A. laricis population, from the end of April until the end of June. The most abundant among flavonoids were the flavanols, mainly catechin and epicatechin, which predominated in the larch needles during the whole period of adelgid infestation. The content of catechin and epicatechin increased following the increase in the adelgid population number. An increase in content occurred also in flavanonols ampelopsin and taxifolin, while the content of the flavonol kaempferol decreased as the population number of A. laricis increased. The analysis of the anatomical structure of needles showed changes in the shape of the needles, the presence of a thicker layer of epicuticular waxes, and a higher number of mesophyll layers as a result of adelgid feeding. [ABSTRACT FROM AUTHOR]

In this study, changes in the amount of polyphenols (C, EC, GC, EGC, EGCG, ECG) and caffeine in different parts (root, stem, leaf and apical bud) of tea plants harvested from gardens with different characteristics in three shoot periods were investigated. Analyses were performed by High-performance liquid chromatography (commonly known as HPLC). The highest amount of polyphenols were obtained from the leaf, apical bud, stem and root parts of the plant, respectively. In this study, the amount of polyphenols was generally found to be higher in the apical bud and leaf parts than in the root and stem. Polyphenols found in the apical bud and leaf of the tea plant, respectively; the highest values of EGCG were between 70.21-73.98 mg/g, caffeine 60.98-39.63 mg/g, EGC 23.83-31.43 mg/g, EC 15.04-15.86 mg/g, GC 6.95-10.92 mg/g and C 1.98-0.58 mg/g. The root and stem contain caffeine in low amounts. Polyphenols were found in the root and stem parts although less compared to the other two organs. [ABSTRACT FROM AUTHOR]

BACKGROUND: Roasting is an essential step in making roasted teas, and its role in producing flavors has been widely studied. However, the variation of potential hazardous compounds during the tea roasting process is still vague. The present study established an effective method based on liquid chromatography‐triple quadrupole‐tandem mass spectrometry to simultaneously determine the variation of acrylamide (AA), 5‐hydroxymethylfurfural (5‐HMF), and free amino acids during the tea roasting process. Meanwhile, the effects of several tea polyphenols on the formation of AA and 5‐HMF were investigated by a wet‐to‐dry thermal model reaction. RESULTS: Medium‐temperature roasted teas had the highest levels of AA and 5‐HMF, with ranges of 0.13–0.15 μg g−1 and 68.72–123.98 μg g−1, respectively. Quantitative results showed that the levels of monosaccharides and amino acids decreased during roasting, which might contribute to the formation of 5‐HMF and AA. Meanwhile, the decrease of epigallocatechin gallate (EGCG), epigallocatechin (EGC), and epicatechin (EC) might be related to their inhibitory effects on 5‐HMF and AA. Thermal model reaction results showed that EGCG and EC significantly inhibited 5‐HMF formation with a decline rate of 33.33% and 72.22%, respectively, mainly by trapping glucose. Gallic acid (GA) also had an inhibitory effect on the formation of AA (decreased by 92.86%) and 5‐HMF (44.44%), mainly through impeding the preliminary reaction of asparagine and glucose. CONCLUSION: The roasting temperature determined the levels of AA and 5‐HMF in teas. Catechins inhibited the formation of 5‐HMF and AA mostly through trapping monosaccharides, while the inhibitory effect of GA was achieved by impeding the reaction. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Chinese Institute of Food Science & Technology / Zhongguo Shipin Xuebao is the property of Journal of Chinese Institute of Food Science & Technology Periodical Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)