Concentrations Of Green Tea Extract Research Articles

Effect of edible coating of gelatin-sodium alginate with the addition of green tea (Camellia sinensis) extract on the characteristics of star fruit (Averrhoa carambola L.) during storage.

Star fruit has a good nutritional value but was very easy to damage. Edible coating can be used to extend the shelf life of star fruit. Green tea had been added to improve the mechanical properties and functional value of edible coating. This study aimed to evaluate the application of edible coating gelatin-sodium alginate with the addition of green tea to the physicochemical and microbiological characteristics of star fruit. This research was conducted by making edible coating solutions from gelatin, sodium alginate, glycerol, and green tea of various concentrations (0%, 5%, 10%, and 15%). The coating solution was applied to star fruit and stored for 1, 6, and 13 days to determine the effect of coating on the physicochemical and microbiological properties of star fruit. The results showed that adding green tea was not significantly different from the color change of the coating solution. However, there was a change in viscosity and pH along with the concentration of green tea extract (p < 0.05). FTIR analyses indicated that an interaction existed between gelatin-sodium alginate and green tea extract. The addition of green tea to star fruit with an edible coating of gelatin and sodium alginate could prevent weight loss (25.84%), reduce respiration rate (11.035mg CO2/kg/h), maintain fruit anatomy, protect against color change, inhibit pH changes (4.22), total titrated acid (0.22%), increase vitamin C (244.55mg/g), and even reduce damage for up to 13 days of storage. This study indicates that edible coating with the addition of green tea might be effective to retain the quality and extend the storage life star fruit.

Green Synthesis of Antimicrobial Silver Nanoparticles using Green Tea Extract: The Role of Concentration and pH

ABSTRACTGreen synthesis for silver nanoparticles (AgNPs) is the process of reducing Ag+ ions to Ag0 by using plant bioactive compounds. Green synthesis is safer, environmentally friendly and cost-effective. Plant bioactive compounds from Camellia sinensis L. (green tea) extract containing polyphenols can be used as a reducer in the formation of silver nanoparticles. This study aims to determine the effect of pH (8, 9, and 10), at 1,5mM AgNO3 concentration and 0,75% green tea extract concentration on the physical characteristics and antibacterial activity of silver nanoparticles prepared by green synthesis method. The synthesized results were evaluated by UV-Vis Spectrophotometer, Dynamic Light Scattering (DLS), SEM, and FTIR. The optimal AgNP synthesis process resulted from the AgNO3 concentration of 1.5 mM with 0.75% green tea extract at pH 10 which showed an absorbance value of 4,420 at λ 435,3 nm, with a particle size of 47,1 nm and a PDI of 0,243. The formation of AgNPs was observed by a change in color to brownish yellow. Antibacterial activity of AgNPs using liquid diffusion method. The results obtained AgNPs for Staphylococcus aureus bacteria has had inhibition at a concentration of 0,187mM and Escherichia coli at a concentration of 0,375mM.Keywords: Silver nanoparticles; green synthesis; green tea extract; pH; antibacterial activity

Evaluation biodegradable films with green tea extract for interleafing sliced meat products

A selection of formulations with different polymers and concentrations of green tea extract was conducted for application as interleafs in sliced meat products. Films were formulated using cellulose acetate, corn starch, and chitosan with the addition of 1.0, 2.5, and 5.0% green tea extract. Higher antioxidant activity was observed with the 1.0% concentration of green tea extract (P < 0.05), regardless of the formulation, with continuous release of the extract for up to 60 days and average IC50 of 0.09 and 0.31 mg/mL for the corn starch and chitosan active films, respectively. Interleafing the sliced ham resulted in lower lipid oxidation after 60 days of storage (P < 0.05). Starch-based films with green tea extract were effective, significantly reducing lipid oxidation in sliced and interleafed cooked ham, suggesting their potential to extend the shelf life of these refrigerated products.

Dietary supplementation with green tea extract improves the antioxidant status and oocyte developmental competence in Italian Mediterranean buffaloes

The aim of this work was to assess the antioxidant status and the developmental competence of oocytes recovered by ovum pick-up (OPU) in Italian Mediterranean buffaloes supplemented with green tea extracts (GTE) for 90 days. Buffalo cows (n = 16) were randomly assigned to a control group receiving no supplement and a treatment group, receiving GTE starting 90 days before OPU, carried out for five consecutive sessions. Blood samples were collected before the start of supplementation with GTE (T0) and at day 45 (T1) and day 90 (T2) of supplementation, to measure ferric reducing activity (FRAP), total antioxidant capacity (TAC), superoxide dismutase (SOD) and catalase (CAT). The antioxidant status of follicles was measured as TAC on the follicular fluid collected from the dominant follicle just prior OPU, coinciding with T2, and at the end of five repeated OPU sessions (T3). Another objective was to assess in vitro the protective effects of green tea extracts on hepatic cells exposed to methanol insult. Different concentrations of GTE (0.5 μM and 1 μM) were tested on cultured hepatic cells and viability, morphology and SOD activity were assessed at 24, 48 and 72 h.Supplementation with GTE increased (P < 0.05) the number of total follicles (8.7 ± 0.5 vs 6.9 ± 0.5), the number and the percentage of Grade A + B cumulus-oocyte complexes (COCs) compared with the control (3.7 ± 0.4 vs 2.3 ± 0.3 and 57.5 ± 4.2 vs 40.4 ± 4.9 %, respectively). Oocyte developmental competence was improved in the GTE group as indicated by the higher (P < 0.05) percentages of Grade 1,2 blastocysts (44.8 vs 29.1 %). In the GTE group, plasma TAC was higher both at T1 and T2, while FRAP increased only at T2, with no differences in SOD and CAT. The TAC of follicular fluid was higher (P < 0.05) in the GTE compared to the control both at T2 and at T3 The in vitro experiment showed that co-treatment with methanol and 1 μM GTE increased (p < 0.01) cell viability at 24 h (P < 0.01), 48 h (P < 0.05) and 72 h (P < 0.01) compared with the methanol treatment co-treatment with 1 μM GTE prevented the decrease in SOD activity observed with methanol at 24 and 48 h of culture. In conclusion, the results of in vivo and in vitro experiments suggest that supplementation with GTE increases buffalo oocyte developmental competence, by improving oxidative status and liver function.

Camellia sinensis L. Extract Suppresses Inflammation on Acute Respiratory Distress Syndrome Cells Models via Decreasing IL-1ß, IL-6 and COX-2 Expressions

Acute Respiratory Distress Syndrome (ARDS) is one of the clinical manifestations in severe COVID-19 patients characterized by acute inflammation resulting in respiratory failure and death. Camellia sinensis L. or green tea extract has many beneficial secondary metabolites including polyphenols which have anti-inflammatory and anti-viral roles. This study was aimed to investigate the activity of green tea extract (GTE) as an anti-inflammatory on ARDS model cells. In this study, rat lung alveolar type II epithelial cells line (L2) was induced by lipopolysaccharide (LPS) to mimic the inflammation process in ARDS. These cells were then treated with GTE to determine the GTE effectiveness in reducing the inflammation. The GTE polyphenol constitutions were first confirmed using Liquid Chromatography with Tandem Mass Spectrometry (LC-MS/MS). The cytotoxic assay was conducted using MTS assay kit to determine the safe range of GTE concentrations that used in the next assay. The effectiveness of the GTE was determined by measuring pro-inflammatory cytokines (IL-1ß and IL-6) and inflammation-mediated enzymes (COX-2), both of which were by ELISA method. Furthermore, this study measured the ACE-2 and TMPRSS-2 gene expressions by qRT-PCR method. The results showed that GTE treatment significantly reduced pro-inflammatory cytokines IL-1ß, IL-6, inflammation-mediated enzyme COX-2, and significantly increased ACE-2 and TMPRSS-2 mRNA expressions. In short, green tea extract possesses the potential to alleviate inflammation. HIGHLIGHTS Acute Respiratory Distress Syndrome (ARDS) is one of clinical manifestations in severe COVID-19 patients characterized by acute inflammation results in respiratory failure and death In lung inflammation, the Angiotensin Converting Enzyme-2 (ACE-2) and Trans-Membrane Protease Serine-2 (TMPRSS-2) genes were lowly expressed, then causes alveolar tissue collapse High levels of inflammatory mediator cytokines would be secreted in respiratory tracts, such as Interleukin (IL)-1β, IL-6, and Cyclooxygenases (COX)-2 Polyphenols in green tea (Camelia sinensis L.) have been reported to have anti-inflammatory activities GRAPHICAL ABSTRACT

Green tea extract and hydroxyl-chloroquine combination enhances apoptosis in A549 non-small cell lung cancer cells.

Polyphenols, including catechins from green tea extract, have long been known for their potential anti-tumour activities. However, the precise mechanisms underlying their actions remain unclear. This study aimed to investigate the effects of green tea extract on A549 cells, a type of non-small lung cancer cells. A549 cells treated with green tea extract (GTE) were examined using an inverted light microscope and a fluorescence microscope. Cell sensitivity was evaluated using the MTT assay, while cell death was assessed using the Tali image-based cytometer. Ultra structural changes were observed using a transmission electron microscope. The findings suggested that even at the highest dose tested (150 µM), GTE did not exhibit toxic effects on A549 cells. Likewise, treatment with GTE resulted in a minimal, dose-dependent increase in the population of apoptotic cells. However, the analysis of cell structures using light and electron microscopy revealed an enhanced accumulation of vacuole-like structures in response to GTE. Moreover, under the fluorescence microscope, an increase in acidic vesicular organelles and the formation of LC3-II puncta were observed following GTE treatment. Assessment of autophagy function indicated that GTE-induced autophagy may serve as a self-protective mechanism against cytotoxicity, as blocking autophagy with bafilomycin A1 reduced cell viability and enhanced necrotic cell death in response to GTE treatment. In summary, our results demonstrate that A549 cells are insensitive to both low and high concentrations of green tea extract, likely due to the induction of cytoprotective autophagy. These findings suggest that the potential utility of GTE in lung cancer therapy may lie in its synergistic combinations with drugs or small molecules that target autophagy, rather than as a standalone therapy.

Evaluation of structural and functional properties of citrus pectin film enriched with green tea extract

AbstractThe effects of green tea extract (GTE) concentrations (0%, 1%, 2%, 3%, 4%, and 5%) on the thicknesses, mechanical strengths, storage/loss moduli, glass transition temperatures (Tg), chemical structures, morphologies, antioxidant activities, moisture contents, and gas permeabilities of low methoxyl pectin films were investigated in this study. A decrease in the percent elongation and moisture contents accompanied by an increase in the tensile strengths, Tg and elastic and storage moduli were observed with increasing, but low concentrations of GTE in the pectin films. This rate of change slowed at higher GTE concentrations. The thicknesses of the pectin films were not significantly affected by the concentrations of GTE. The FTIR results showed increasing ester and hydrogen bonding formations with increasing concentrations of GTE from 0% to 2% in the pectin. When the GTE concentration increased from 2% to 5%, there was an increase in ester, but a decrease in the H‐bonding. The x‐ray diffraction results showed that the crystallinity of the films increased as a result of increasing GTE contents. The results of the antioxidant activities and oxygen and water vapor barrier properties showed an enhancement due to the higher concentrations of GTE. Therefore, GTE can be incorporated into low methoxyl pectin in order to make films with desired mechanical strength, gas barrier, and antioxidant properties.

Effect of different concentrations of green tea on Cryopreservation of German Shepherd dog

To investigate the Effect of adding different concentrations of green tea extract as an antioxidant on specific physical semen characteristics of German Shepherd dogs during various steps of frozen semen processing this study was carried out. A total (of 20) good Ejaculate semen samples were collected in a plastic bag from German Shepherd dogs aged 3-4 yearsIn different locations (dog breeding).To achieve the current study's main objectives, two experiments were designed through periods extended from the beginning of December 2021 until the end of May 2022. The investigations included studying the physical properties of raw Semen (ejaculate volume, semen color, consistency, motility percentage, progressive motility percentage, dead sperm percentage, sperm abnormalities percentage, and hypo-osmotic swelling test (HOST). After that, semen samples were diluted with Tris supplemented with antioxidants. The physical properties of Semen were followed after cooling and after freezing (post-thawing). In the experiment, ten ejaculates were collected. Dilution of Semen was performed with Tris supplemented with two T1, T2, and T3) were cooled slowly up to 5C and equilibrated, packed into 0.5 ml straws, and put in vapor nitrogen (-196C) for 5-10 minutes after that, stored for 48and 72 hr in liquid Nitrogen (-196C). Progressive motility percentage, dead sperm percentage, sperm abnormalities percentage, and hypo-osmotic swelling test (HOST) were evaluated after cooling and post-thawing (Submerging the straws in the water bath at 37C for 30 seconds). It can be concluded from the present study that adding green tea extract as an antioxidant to the semen extender improves the ability to freeze, especially in the treatment T3 (0.01 mg/5 ml) and the T2 (0.05 mg/5 ml). This additive can decrease the negative Effect of freezing in liquid Nitrogen compared to the control group.

Oat Milk Tea Model System: Exploring the Stability of Milk Tea and the Bioaccessibility of Green Tea Polyphenols.

Oat milk has become preferential because of its low calorie nature and high dietary fiber content, but its ability to "curdle" when mixed with tea can affect the consumer acceptability for oat milk tea. In this study, a model system for oat milk tea was made by combining oat milk and green tea extract to evaluate the impacts of the oat milk matrix and green tea extract concentration on the stability and polyphenol bioaccessibility. The stability analysis results showed that adding green tea extract to oat milk influenced the stability of the oat milk tea model systems. In contrast, the 3.0% fat oat milk tea model system exhibited a higher stability than the 1.5% fat oat milk tea model system. In simulated gastrointestinal digestive experiments, tea polyphenols in the oat milk tea model systems were relatively stable in oral and stomach digestive stages, while they clearly degraded in the small intestine digestive stage. Furthermore, the bioaccessibility of tea polyphenols was higher for the 3.0% fat oat milk tea model system than for the 1.5% fat oat milk tea model system, especially at low concentrations of green tea extracts (0.05%~0.25%). These results may provide a theoretical reference and data for the formulation of oat milk tea and the bioaccessibility of tea polyphenols in food matrices.

Влияние экстракта зеленого чая на процесс молочнокислого брожения и органолептические показатели ферментированного напитка на основе яблочного сока

We investigated the influence of adding green tea extract to apple juice on the lactic acid fermentation process induced by a starter culture of lactic acid bacteria (LAB) from Streptococcus thermophilus + Lactobacillus bulgaricus and the organoleptic characteristics of the resulting fermented beverage. The juice was obtained from Simirenko apples harvested in 2022 in the Krasnodar Region (Russia). To increase juice yield, the apple pulp underwent fermentative treatment with the Vegazym M enzyme preparation. The content of polyphenolic compounds in the aqueous extract of Green Spirals green tea (China), was determined spectrometrically using the Folin–Ciocalteu reagent and amounted to 20 mg/dm3. The extract was added to the juice at volumes of 5, 10, and 15 cm3/100 cm3. The rate of utilization of raw material components by LAB during fermentation was assessed by changes in the mass concentrations of dry substances, sugars, and titratable acids over the period from 0 to 24 hours and from 24 to 48 hours of fermentation. It was shown that treatment of apple pulp with Vegazym M at a concentration of 0.09% increased juice yield by more than 14%. It was found that as the concentration of green tea extract in the fermentable apple juice increased the activity of lactic acid bacteria also increased. The highest rate of utilization of apple juice components and the rate of accumulation of titratable acids by LAB were observed at a concentration of 15 cm3 of green tea extract per 100 cm3 of juice. The highest rate of metabolic processes during fermentation by LAB of apple juice with green tea extract was observed in the first 24 hours of the fermentation process. It was demonstrated that adding green tea extract to apple juice enhances the aroma and taste of the fermented beverage. The fermented beverage from apple juice with the addition of 10 cm3 of green tea extract per 100 cm3 exhibited the best organoleptic characteristics.

Green tea extract improved minced mutton quality during chilled storage

Natural antioxidant has been used to prevent lipid oxidation and microbiological development in meat and meat products. This study was carried out to evaluate the effects of different concentrations of green tea extract on minced mutton quality during chilled storage. The minced mutton was divided into 5 treatment groups, with TGE1 as negative control while TGE2, TGE3, TGE4 and TGE5 were added with green tea extracts at 0.5%, 1%, 1.5% and 2%, respectively. The pH, myoglobin, water holding capacity (WHC), drip and cooking loss of minced mutton were studied during chilled storage at days 0, 3, 6, 9 and 12. Present findings showed that minced mutton added with green tea extract had significantly higher (P&lt;0.05) pH, myoglobin content and WHC than the untreated control group at days 3, 6, 9 and 12. In addition, minced mutton with added green tea extract also had significantly lower (P&lt;0.05) drip and cooking loss than the control group. This study also showed that a higher concentration of green tea extract added had a better effect on the meat quality traits measured. Taken together, these results indicate that the addition of green tea extract improved the minced mutton quality.

Effect of green tea polyphenols on the techno-functional and nutraceutical properties of himalayan rice (Mushk Budji)

This study explores the effect of green tea extract (GTE) on the properties of rice starch. The GTE was obtained using ultrasonication and incorporated in rice starch at different concentrations (5, 10, 15, and 20%) to make a green tea extract-starch complex (GTES). The morphology and structure of GTES were studied using scanning electron microscopy (SEM) and attenuated total reflectance fourier transform infra-spectroscopy (ATR-FTIR). With the increase in the concentration of GTE, GTES depicted a decrease in transmittance corresponding to the wavelength of 3300 cm−1, 2926 cm−1, and 1695 cm−1 representing O-H, C–H, and C–O stretching vibrations, respectively. Scanning electron microscopy (SEM) displayed an irregular, polyhedral and rough surface of GTES. The resistant starch (RS) and syneresis of GTES increased with the increase in the concentration of GTE. GTES displayed significantly low (p ≤ 0.05) amylose content, solubility, and swelling index. The nutraceutical potential of GTES was evaluated in terms of antioxidant potential which revealed that as the GTE concentration increased, the antioxidant potential increases. Overall the GTE-starch complex can be utilized to produce functional foods with improved RS and antioxidant potential.

MAP30 transgenic tobacco lines: from silencing to inducing.

DNA methylation is one of the most important epigenetic event that regulates gene expression. In addition to DNA methylation, transgene copy number may induce gene silencing. Therefore, the study of these cases is useful for understanding of gene silencing regulation. In this study, the methylation pattern of 35S promoter was investigated in the second generation of MAP30 transgenic tobacco lines. Therefore, the genomic DNA melting curve changes were investigated before and after bisulfite treatment by real time PCR. To determine the exact position of methylation, the samples were sequenced after bisulfite treatment. Observation of decrease in DNA melting curve of expressing line in comparison with silenced line confirmed the presence of DNA methylation in silenced line. In order to induce the MAP30 expression, the silenced line was treated using different concentrations of Azacytidine and green tea extracts. The results showed that all concentrations of green tea extracts for 6days and the concentrations of 3 and 10μM Azacytidine for 10 and 3days could induce the expression of MAP30 in silenced line respectively. Finally, the transgene copy number was estimated using real time PCR, as silenced line contained more than two copies while the lines expressing MAP30 contained only one or two copies. Finally, we found that the presence of DNA methylation and also multiple gene copy numbers in silenced line have been led to gene silencing. Moreover, the effect of green tea extract on DNA methylation showed incredible results for the first time.

Statistical optimization of silver nanoparticle synthesis by green tea extract and its efficacy on colorimetric detection of mercury from industrial waste water

For the optimization of silver nanoparticle production, a central composite design was used with three parameters: AgNO3 concentration, green tea extract concentration, and temperature at three different levels. The size of the synthesized silver nanoparticle, its UV absorbance, zeta potential, and polydispersity index were set as the response parameters. Silver nanoparticles obtained in the optimization process were characterized and its efficacy on colorimetric detection of mercury was evaluated. The response variables were significant for the factors analyzed, and each variable had a significant model (P < 0.05). The ideal conditions were: 1 mM AgNO3, 0.5% green tea extract, and 80 °C temperature. To analyze the produced AgNPs under certain ideal conditions, Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and X-ray diffraction (XRD) were used. The UV–visible spectra of AgNPs revealed an absorption maxima at 424 nm. The XRD pattern reveals a significant diffraction peak at 38.25°, 44.26°, 64.43°, and 77.49°, which corresponds to the (111), (200), (220), and (311) planes of polycrystalline face-centered cubic (fcc) silver, respectively. The TEM and SEM analyses confirmed that the particles were spherical, and dynamic light scattering study determined the average diameter of AgNPs to be 77.4 nm. The AgNPs have a zeta potential of −62.6 mV, as determined by the zeta sizer analysis. The AgNPs detects mercury at a micromolar concentration. Furthermore, the environmentally friendly generated AgNPs were used to detect mercury in a colorimetric method that was effectively employed for analytical detection of Hg2+ ions in an aqueous environment for the purpose of practical application.

بررسی اثر اینولین و عصاره چای سبز بر زندهمانی بیفیدوباکتریوم لانگوم و خصوصیات فیزیکوشیمیایی بستنی سویای سین بیوتیک

Abstract Background and objectives: Today, consumers tend to eat fresh food with high nutritional and health benefits. Food, in addition to eliminating hunger and providing essential nutrients, should improve the health and physical and mental health of the consumer. Probiotics are living microorganisms that have a healthy effect if they are consumed alive and sufficiently. Using appropriate prebiotic compounds and selecting suitable carriers for probiotics can increase the growth and activity of these beneficial bacteria. Soybeans and their products are considered to be good carriers for probiotic microorganisms that can play an effective role in increasing the viability of probiotic bacteria. The purpose of this study was to investigate the effects of inulin prebiotic and antioxidant green tea on increasing the viability time of Bifidobacterium longum in synbiotic soy ice cream. Materials and methods: In order to produce synbiotic soy ice cream, the green tea extract in concentrations of 1, 2 and 3% and inulin in proportions of 1, 2 and 3% and also probiotic bacteria Bifidobacterium Longum in the amount of 107 Cfu/ml were added to synbiotic soy ice cream formulation. Therefore, 10 treatments were designed according to completely randomized design with three replicates. Tests of determination the percentage of polyphenolic compounds, percentage of total acidity, percentage of increasing overrun, peroxide number (mEq/Kg), viscosity evaluation (cp), color assessment (lighting, redness and yellowness index), sensory assessments (odor, taste, texture and overall acceptance) were performed one day after production and the survival rate of Bifidobacterium Longum (Cfu/ml) of soybean ice cream samples done during 21 days of storage at -18°C. For data analysis of the results of the tests, Duncan's test for comparison means at probability level of 5% was used by Minitab version 16 software. Results: The results showed that increasing the concentration of inulin and green tea extract in the synbiotic soy ice cream formulation, overrun, yellowness index (b*), lighting index (L*), score of sensory indexes including odor, taste, texture and overall acceptance decreased and acidity, the viability rate of Bifidobacterium longum, viscosity and redness index (a*) increased. Bifidobacterium longum population after 21 days of storage in all treatments, including control, was higher than 106 Cfu/ml. In contrast to inulin increase in the concentration of green tea extract had a significant effect on the reduction of peroxide index. The sensory indices of the treatment containing 1% green tea extract and inulin were not significantly different with the control sample and were presented as superior treatment in this study. Sensory indexes of treatments containing 1% green tea extract and inulin were not significantly different with the control sample and were presented as a superior treatment in this study. Conclusion: By using 1% green tea extract and 1% inulin can be possible to produce a synbiotic soy ice cream with optimal qualitative and sensory properties with good health properties.

Thin-layer hydration method to prepare a green tea extract niosomal gel and its antioxidant performance

Abstract This study aimed to prepare a niosomal gel of green tea (Camellia sinensis) extract containing catechins, mostly epigallocatechin-3-gallate (ECGC), as a potent antioxidant. Niosomes can increase EGCG's stability and penetration into the skin for a better therapeutic effect. Niosomes were prepared by a thin-layer hydration method, were evaluated for their vesicle shape, particle size, polydispersity index, zeta potential and entrapment efficiency, and then incorporated into gels using sodium alginate as a gelling agent. Three niosomal gel formulations were prepared with different concentrations of niosomes green tea extract. Afterwards, organoleptic properties, chemical and physical characteristics, antioxidant activity, and stability and irritability of the niosomal gels were investigated. The different concentrations of green tea extract had a significant effect on the physical characteristics, but not on the chemical ones. Its antioxidant activity was determined using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging method. The 50% extract green tea niosomes gel showed the highest inhibition value (25.13%). The stability was determined by freeze–thaw and real-time methods; they showed a decrease in pH, but still within the pH range of skin. The irritability test used was the Hen's Egg Test-Chorioallantoic Membrane (HET-CAM) method, which showed no irritation for all formulas. In conclusion, 50% green tea extract niosomes gel results showed it to be the best formulation with optimal antioxidant results.

Green Tea Attenuates methomyl-Induced Cardiac Toxicity Through Modulating Oxidative Stress and Nuclear Factor kappa B Up- Regulation in Mice

ABSTRACT Methomyl (ME) is a carbamate insecticide that is causes a change in biochemical parameters and affects the oxidative state in the body through the production of free radicals. Herbal medicines derived from plant extracts are useful in treating many diseases, as they are considered natural antioxidants that have a protective role against toxins. This study aimed to evaluate the ability of green tea extract (GTE) to treat ME-induced cardiac toxicity in experimental animals. The experimental animals were divided into five groups. Blood and tissue were collected to estimate the biochemical parameters. ME caused significantly elevated levels of AST, LDH, NF-κB, and malondialdehyde. While a significant decrease was observed in levels of superoxide dismutase, a decrease in glutathione and glutathione-S-transferase was observed. Alterations in these biochemical markers were referred to oxidative stress-induced cardiac damage. The administration of GTE at a concentration (1.5%) to the ME treated group caused the tested biochemical parameters to appear close to those of the control group. GTE alleviates ME-induced oxidative stress in female albino mice. A higher concentration of GTE {1.5%} appears to have a better therapeutic effect than a lower concentration of extract {0.75%} in cardiac toxicity ME.

Green tea extract as a cryoprotectant additive to preserve the motility and DNA integrity of human spermatozoa.

Cryopreservation impairs sperm quality and functions, including motility and DNA integrity. Antioxidant additives in sperm freezing media have previously brought improvements in postthawed sperm quality. Green tea extract (GTE) is widely considered as an excellent antioxidant, and its beneficial role has been proven in other human cells. This study aims to evaluate the GTE as a potential additive in cryopreservation media of human spermatozoa. In part one, the semen of 20 normozoospermic men was used to optimize the concentration of GTE that maintains sperm motility and DNA integrity against oxidative stress, induced by hydrogen peroxide (H2O2). Spermatozoa were treated with GTE at different concentrations before incubation with H2O2. In part two, the semen of 45 patients was cryopreserved with or without 1.0 ng ml−1 GTE. After 2 weeks, the semen was thawed, and the effect on sperm motility and DNA fragmentation was observed. Our data showed that GTE significantly protected sperm motility and DNA integrity against oxidative stress induced by H2O2 when added at a final concentration of 1.0 ng ml−1. We found that the addition of 1.0 ng ml−1 GTE to cryopreservation media significantly increased sperm motility and DNA integrity (both P < 0.05). More interestingly, patients with high sperm DNA damage benefited similarly from the GTE supplementation. However, there was no significant change in the reactive oxygen species (ROS) level. In conclusion, supplementing sperm freezing media with GTE has a significant protective effect on human sperm motility and DNA integrity, which may be of clinical interest.

Determination of the influence of natural antioxidant concentrations on the shelf life of sunflower oil

The influence of natural antioxidants from different types of vegetable raw materials on the processes of oxidative and hydrolytic spoilage of sunflower oil during storage is studied. Plant antioxidants are more environmentally friendly and safer than synthetic ones. Green tea leaves and oak bark were used as vegetable raw materials. Water-ethanol extracts from vegetable raw materials were added to oil samples in experimental concentrations. The samples were stored in the laboratory conditions at the temperature of (20±2) °C. The study was performed for 5 months. The values of the acid and peroxide numbers were determined. The most effective blend of antioxidants showed the increase in the acid number from 0.12 to 0.20 mg KOH/g (concentration of green tea extract – 0.05 %, without the addition of oak bark extract). According to the values of the peroxide number, the most effective blends of antioxidants were the experiment points with the following green tea extract:oak bark extract ratio: (0.05:0.05) %, (0.025:0.025) %, (0.025:0.05) %, (0.05:0.025) %. To determine the induction period of oil and, accordingly, its shelf life under experimental conditions, the values of the peroxide numbers were used. It is rational to use extractives from oak bark and green tea under the following conditions: the concentration of each of the antioxidant extracts in terms of dry matter – (0.025‑0.04) %. The maximum induction period is 100 days. The efficiency of natural antioxidants in terms of the concentration of oak bark and green tea extracts is 0.05 and 0.025 %, respectively, was compared to the effectiveness of the corresponding concentration of one of the synthetic antioxidants – butylhydroxyanisole. When using butylhydroxyanisole, the induction period of oil was 65 days, and when using natural antioxidants – 74 days

Antioxidant activity and physical properties of pH-sensitive biocomposite using poly(vinyl alcohol) incorporated with green tea extract

Our study focused on the preparation and characterization of biocomposite films consisting of poly(vinyl alcohol) (PVA) and green tea extract (GTE) with a small amount of glycerol as a plasticizer. Scanning electron microscopy (SEM) showed that both the surface and cross-section of the GTE-PVA biocomposite films were smooth and uniform. Incorporation of GTE could considerably alter the optical and mechanical properties of the pure PVA film. Notably, the GTE-PVA biocomposite films presented better water vapor and UV–vis light barrier properties and higher mechanical strength than the pure PVA film. The antioxidant ability of the biocomposite films was evaluated by measuring the 2,2-diphenyl-1-picrylhydrazyl radical scavenging and ferric reducing power in terms of the total phenolic content. The GTE-PVA biocomposite films showed higher antioxidant activity than the pure PVA film, and the antioxidant activity increased with increasing GTE concentration. The color of the GTE-PVA biocomposite films became yellow when the pH was lower than 6 and became dark red when the pH was higher than 6. Moreover, color variations were observed in the GTE-PVA biocomposite films by changing the pH. These results suggest that GTE-PVA composite films may be used as a promising antioxidant and visible pH-sensing food packaging materials.