Differential Anti-Fibrotic and Remodeling Responses of Human Dermal Fibroblasts to Artemisia sp., Artemisinin, and Its Derivatives.

Fibrosis is a ubiquitous pathology, and prior studies have indicated that various artemisinin (ART) derivatives (including artesunate (AS), artemether (AM), and dihydroartemisinin (DHA)) can reduce fibrosis in vitro and in vivo. The medicinal plant Artemisia annua L. is the natural source of ART and is widely used, especially in underdeveloped countries, to treat a variety of diseases including malaria. A. afra contains no ART but is also antimalarial. Using human dermal fibroblasts (CRL-2097), we compared the effects of A. annua and A. afra tea infusions, ART, AS, AM, DHA, and a liver metabolite of ART, deoxyART (dART), on fibroblast viability and expression of key fibrotic marker genes after 1 and 4 days of treatment. AS, DHA, and Artemisia teas reduced fibroblast viability 4 d post-treatment in up to 80% of their respective controls. After 4 d of treatment, AS DHA and Artemisia teas downregulated ACTA2 up to 10 fold while ART had no significant effect, and AM increased viability by 10%. MMP1 and MMP3 were upregulated by AS, 17.5 and 32.6 fold, respectively, and by DHA, 8 and 51.8 fold, respectively. ART had no effect, but A. annua and A. afra teas increased MMP3 5 and 16-fold, respectively. Although A. afra tea increased COL3A1 5 fold, MMP1 decreased >7 fold with no change in either transcript by A. annua tea. Although A. annua contains ART, it had a significantly greater anti-fibrotic effect than ART alone but was less effective than A. afra. Immunofluorescent staining for smooth-muscle α-actin (α-SMA) correlated well with the transcriptional responses of drug-treated fibroblasts. Together, proliferation, qPCR, and immunofluorescence results show that treatment with ART, AS, DHA, and the two Artemisia teas yield differing responses, including those related to fibrosis, in human dermal fibroblasts, with evidence also of remodeling of fibrotic ECM.

Effects of instant controlled pressure drop treatment combined with refractance window drying on infusion quality of made green tea.

BACKGROUND: The study aimed to determine the effects of instant controlled decompression of steam pressure, termed as ICPD (instant controlled pressure drop) on fresh tea leaves, when combined with refractance window drying (RWD) of rolled green teas during green tea manufacturing. The ICPD steam treatment pressure (TP; 0.1-0.3 MPa), treatment time (TT; 10-20 s) and refractance window drying temperature (RWDT; 70-90 °C) were used as the processing parameters for manufacturing of green tea. RESULT: Response surface methodology was employed to enumerate the effects of ICPD process conditions and temperature of RWD on total phenolic content (TPC), total flavonoid content (TFC) and DPPH (1,1-diphenyl-2-picrylhydrazyl) radical scavenging activity of the green tea infusion. An optimum condition for green tea processing was found at TP 0.2 MPa, TT 20 s with RWDT at 70 °C. In comparison to made green tea manufactured without ICPD treatment, the ICPD treated green tea showed enhanced TPC, TFC and DPPH radical scavenging activity along with better colour and sensory attributes. The microstructural study of ICPD treated green tea samples showed more deformed cell surface integrity, larger stomatal pore size and cracks at the leaf surface in comparison with non-treated green tea sample. CONCLUSION: Present study reveals that an ICPD treatment at 0.2 MPa for 20 s can be used as an alternative to the traditional enzyme inactivation step of hot water treatment, for green tea leaves to improve the infusion quality in terms of increased levels of TPC and TFC and DPPH radical scavenging activity. © 2024 Society of Chemical Industry.

Degradation of imidacloprid and acetamiprid in tea (Camellia sinensis) infusion by ultraviolet light irradiation.

The degradation of imidacloprid and acetamiprid in tea infusion by ultraviolet (UV) light irradiation was investigated in this study. Results showed that the influence of UV light irradiation on the quality of tea infusion was controllable and UV light irradiation was effective on the degradation of both pesticides. The maximum removal rates were 75.2% for imidacloprid and 17.6% for acetamiprid after irradiation (650 µW/cm,2 120 min). The degradation of both pesticides followed the first-order kinetics model. Three degradation products were identified for imidacloprid and one for acetamiprid based on liquid chromatography-tandem mass spectrometry analysis. The degradation pathway of imidacloprid involved in the cleavage of C-C bond with the loss of nitro group followed by the hydrogenation, oxidation and hydrolysis, while the degradation of acetamiprid involved in the oxidation at the chlorine atom with the bonding of C atoms at positions 1 and 4 on the pyridine ring. Simultaneously, the toxicity of both pesticides was mitigated by UV light irradiation according to LO2 cell toxicity evaluation. The study provided a low-cost and effective way to reduce imidacloprid and acetamiprid from tea infusion, and it has the potential to be applied to the ready-to drink tea beverage production in industrial scale.

Phenylboronic acid-functionalized cross-linked chitosan magnetic adsorbents for the magnetic solid-phase extraction of benzoylurea pesticides.

In this study, a 4-formylphenylboronic acid-modified cross-linked chitosan magnetic nanoparticle (FPBA@CCHS@Fe3 O4 ) was fabricated. The synthesized material was utilized as the magnetic solid-phase extraction adsorbent for the enrichment of six benzoylurea pesticides. In addition to B-N coordination, FPBA@CCHS@Fe3 O4 interacts with benzoylureas through hydrogen bonds and π-π stacking interaction on account of rich active groups (amino and hydroxyl) and aromatic rings in structure. Compared to traditional extraction methods, less adsorbent (20 mg) and reduced extraction time (3 min) were achieved. The adsorbent also exhibited good reusability (no less than 10 times). Coupled with a high-performance liquid chromatography-diode array detector, satisfactory recoveries (89.1-103.9%) and an acceptable limit of detection (0.2-0.7 µg/L) were obtained. Under optimized conditions, the established method was successfully applied to the tea infusion samples from six major tea categories with acceptable recoveries ranging from 76.8 to 110%, indicating its application potential for the quantitative detection of pesticides in complex matrices.

Concentrations, leachability, and health risks of mercury in green tea from major production areas in China.

Green tea has many health benefits and is the most consumed type in China. However, the heavy metals and contaminants in tea can also pose a great risk to human health. In this study, mercury (Hg) concentration in green tea collected from 11 provinces in China was examined. The leaching characteristics of Hg during brewing and the associated exposure to drinkers were also evaluated. Results indicated a low potential of Hg accumulation in green tea. The Hg content of green tea from Wanshan District, Guizhou Province-which has the largest Hg mine in China and is severely contaminated by Hg-could be limited by controlling the harvest time of tea leaves. The average Hg content of green tea from 43 tea production sites in China was only 6.3 ± 6.4 µg/kg dry weight. The brewing experiments of green tea showed that the leaching ratio of Hg was 22.61 ± 7.58% for 40 min of a single brew, and increased to 32.83 ± 12.37% after four rounds (3 min/ round) of brewing. The leaching of Hg from tea leaves was significantly affected by leaching time, temperature, and solid-liquid ratio but not by water hardness. The risk of Hg exposure from green tea intake was found to be very low, with an average hazard quotient (HQ) value of only 1.82 ± 1.85% for a single brew in 40 min and 2.64 ± 2.68% after four rounds of brewing. However, in some highly contaminated areas, with HQ values as high as 43.12 ± 2.41%, green tea intake may still pose a high risk of Hg exposure, and this risk should not be ignored.

Optimization of reaction conditions for the design of cereal-based dietary fibers with high antioxidant capacity.

BACKGROUND: Bound antioxidants are distinguished by their strong potential to defend the body against oxidative stress. Cereal bran fractions contain antioxidant compounds bound to dietary fiber, but this only occurs to a limited extent. Increasing the quantity of bound antioxidant compounds using soluble phenolic compounds is thought to be a possible method for designing cereal-based dietary fibers with high antioxidant potential. Certain cereal bran samples (wheat, oat, rye, and rice) were reacted with different concentrations of beverages (green tea infusion, black tea infusion, espresso, and red wine), rich in various soluble phenolic compounds. The interactive effects of parameters (time, temperature, and pH) and the optimum conditions for the reaction were determined using response surface methodology. RESULTS: Green tea infusion (30 g·L-1 ) was found to be the most effective beverage. The pH rather than the time and temperature had significant (O p < 0.0001) effects on the reaction. Neutral or slightly alkaline conditions (pH 7.0-7.9) and mild temperatures (at about 50 °C) were found to be optimum to increase the antioxidant capacity of cereal bran samples. The total antioxidant capacity of oat bran treated with green tea infusion under optimum conditions (53.3 °C, pH 7.4, 60.0 min) reached 226.42 ± 0.88 mmol Trolox equivalent·kg-1 . The free amino groups in cereal bran were also found to decrease (32-95%) after treatment. CONCLUSION: It is possible to design functional cereal-based dietary fibers, rich in bound antioxidant compounds through treatment with green tea infusion under optimum conditions. © 2022 Society of Chemical Industry.

The performance of water-soluble fluoride transformation in soil-tea-tea infusion chain system and the potential health risk assessment.

BACKGROUND: Water-soluble fluoride (WS-F) can be absorbed directly by tea plants from soil and comprises a major source of dietary F in tea consumers. To reveal the WS-F accumulation in tea leaves and assess WS-F health risks, 70 sets of samples including tea leaves at three maturity stages and corresponding topsoil were collected from Xinyang, China. The WS-F contents in tea samples and pH values in soil samples were determined. RESULTS: The contents of WS-F in tea leaves exhibited a positive correlation with leaf maturity. The contents of WS-F in tea leaves showed a positive correlation with WS-F contents in the soil as the soil pH value exceeds 5. All the bud with two leaves samples, 84.29% of the third to sixth leaves samples, and 78.57% mature leaves samples in 5-min infusion tend to be no health threat. The leaching characteristics of WS-F from tea leaves were influenced by the leaf maturity and soaking time. CONCLUSION: Taking measures to control pH and WS-F concentration of plantations soil, as well as drinking tea infusion made from young leaves or reducing soaking time could decrease the WS-F health risk. © 2021 Society of Chemical Industry.

Effect of Ferrous Ion on Heat-Induced Aroma Deterioration of Green Tea Infusion.

Aroma deterioration is one of the biggest problems in processing tea beverages. The aroma of tea infusion deteriorates fast during heat sterilization and the presence of ferrous ion (Fe2+) aggravates it. The underlying mechanism remains unveiled. In this study, Fe2+ was verified to deteriorate the aroma quality of green tea infusion with heat treatment. Catechins were necessary for Fe2+-mediated aroma deterioration. By enhancing the degradation of catechins, Fe2+ dramatically increased the production of hydrogen peroxide (H2O2). Fe2+ and H2O2 together exacerbated the aroma of green tea infusion with heat treatment. GC-MS analysis revealed that the presence of Fe2+ enhanced the loss of green/grassy volatiles and promoted the formation of new volatiles with diversified aroma characteristics, resulting in a dull scent of green tea infusion. Our results revealed how Fe2+ induced aroma deterioration of green tea infusion with heat treatment and could help guide tea producers in attenuating the aroma deterioration of tea infusion during processing.

Changes in the viscosity, textural properties, and water status in yogurt gel upon supplementation with green and Pu-erh teas.

The present research was established to study the effect of green tea and Pu-erh tea (PT) additives on the mechanical and hydration properties of yogurt gels using a combination of nuclear magnetic resonance, rheological, and textural studies. Tea infusions (0-15 mL/100 mL) were added to batch milk before fermentation with yogurt culture. Obtained dairy products were analyzed for the water mobility and organization, viscosity, and texture profile. Results of the rheological and nuclear magnetic resonance studies suggested that stabilization of the yogurt gel structure was achieved upon supplementation with tea infusions. Generally, green tea fortification produced yogurts with more consolidated gel structure, tighter interacting water, and less susceptibility to shearing and temperature changes than PT treatments. In contrast, PT yogurts were more viscous and characterized by 8 to 17% lower hardness values. This knowledge can be useful for developing novel dairy products with desired structure and consistency.

Polycyclic aromatic hydrocarbons (PAHs) in dry tea leaves and tea infusions in Vietnam: contamination levels and dietary risk assessment.

The total mean ∑[Formula: see text] in samples were from 75.3 to 387.0 ng/g dry weight (d.w) and showed high value in black dry tea, followed by herbal, oolong, and green tea. The mean ∑[Formula: see text] (a combination of benz[a]anthracene, chrysene, benzo[b]fluoranthene, and benzo[a]pyrene) values were 54.3 ng/g, 16.4 ng/g, 14.2 ng/g, and 6.6 ng/g for black, herbal, green, and oolong teas, respectively. Concentration for benzo[a]pyrene (BaP) was from 0.4 to 35.8 ng/g, and the BaP equivalent concentration values ranged from 0.3 to 48.1 ng/g. There was only 1 black tea sample that BaP concentration exceeded the maximum level according to European Union (EU) standards. Tea samples marketed in Vietnam showed insignificant difference with the samples from other origins by same analytical method. Black teas showed high PAHs contents in dry tea samples but the released percentage of sum of PAHs from tea-to-tea infusion was lower than that in other tea type samples. The released percentages of PAH4 from tea-to-tea infusion were 40.7, 15.4, and 1.9 for green, herbal, and black tea. High temperature in black tea manufacturing processes might reduce essential oil content in tea that might effect on the PAHs partially release into the infusion. Indeed, based on EU regulations, we may conclude that tea consumers are safe in risk of exposure to PAHs obtained from teas.

Comparative Analyses on the Bioactive Compounds and in Vitro Antioxidant Capacity of Tea Infusions Prepared from Selected Medicinal Fruits.

This study was conducted to analyze the bioactive compounds and in vitro antioxidant capacity of tea infusions prepared from whole and ground medicinal fruits, including gardenia, jujube, magnolia, quince, and wolfberries. The dried medicinal fruit samples were ground, and then passed through a 60-mesh sieve (pore size, 250 µm). Hot water (80 °C) infusions of whole and ground fruits were examined. In average of both whole and ground tea infusions, the maximum bioactive compounds were found in gardenia (ß-carotene, lycopene, and vitamin C), magnolia (total chlorophyll and anthocyanin), quince (flavonoid), and wolfberries (phenolic), and the maximum antioxidant capacity was found in quince (ABTS and DPPH) and wolfberries (NSA). Whole fruit tea infusions showed a higher brightness than the ground fruit tea infusions. The total chlorophyll, anthocyanin, ß-carotene, lycopene, phenolic, flavonoid, and vitamin C contents were found to be significantly (p≤0.001) higher in the ground fruit tea infusions than in the whole fruit tea infusions; additionally, the ground fruit tea infusions had a higher antioxidant capacity especially ABTS, DPPH and NSA. Therefore, the ground fruit tea infusions appeared to be more powerful with regard to the contents of bioactive compounds and antioxidant capacities than the whole fruit tea infusions.

Estimated assessment of cumulative dietary exposure to organophosphorus residues from tea infusion in China.

BACKGROUND: China has the world's largest tea plantation area in the world. To sustain high yields of the tea, multiple pesticides are used on tea crops to control pests. Organophosphorus (OP) pesticides are among the most widely used types of agricultural pesticides in China. As tea is a significant potential source of exposure to pesticide residues, the public concern has increased in relation to pesticide residues found in tea in China. The aim of the study was to estimate cumulative dietary exposure to OP residues from tea infusion for Chinese tea consumers to determine whether exposure to OP residues from tea infusion is a cause of health concern for tea consumers in China. METHODS: OP residue data were obtained from the China National Monitoring Program on Food Safety (2013-2014), encompassing 1687 tea samples from 12 provinces. Tea consumption data were obtained from the China National Nutrient and Health Survey (2002), comprising 506 tea consumers aged 15-82 years. The transfer rates of residues from tea leaves into tea infusions were obtained from the literature. The relative potency factor (RPF) approach was used to estimate acute cumulative exposure to 20 OP residues from tea infusion using methamidophos as the index compound. Dietary exposure was calculated in a probabilistic way. RESULTS: For tea consumers, the mean and the 99.9th percentile (P99.9) of cumulative dietary exposure to OP residues from tea infusion equalled 0.08 and 1.08 µg/kg bw/d. When compared with the acute reference dose (ARfD), 10 µg/kg bw/d for methamidophos, this accounts for 0.8 and 10.8% of the ARfD. CONCLUSIONS: Even when considering OP residues from vegetables, fruits and other foods, there are no health concerns based on acute dietary exposure to OP residues from tea infusion. However, it is necessary to strengthen the management of the OP pesticides used on tea in China to reduce the risk of chronic dietary exposure to OPs from tea infusion.

Micronutrients (B, Co, Cu, Fe, Mn, Mo, and Zn) content in made tea (Camellia sinensis L.) and tea infusion with health prospect: A critical review.

Tea (Camellia sinensis L.) is a perennial acidophilic crop, and known to be a nonalcoholic stimulating beverage that is most widely consumed after water. The aim of this review paper is to provide a detailed documentation of selected micronutrient contents, viz. boron (B), cobalt (Co), copper (Cu), iron (Fe), manganese (Mn), molybdenum (Mo), and zinc (Zn) in made tea and tea infusion. Available data from the literature were used to calculate human health aspect associated with the consumption of tea infusion. A wide range of micronutrients reported in both made tea and tea infusion could be the major sources of micronutrients for human. The content of B, Co, Cu, Fe, Mn, Mo, and Zn in made tea are ranged from 3.04 to 58.44 µg g-1, below detectable limit (BDL) to 122.4 µg g-1, BDL to 602 µg g-1, 0.275 to 13,040 µg g-1, 0.004 to 15,866 µg g-1, 0.04 to 570.80 µg g-1 and 0.01 to 1120 µg g-1, respectively. Only 3.2 µg L-1 to 7.25 mg L-1, 0.01 µg L-1 to 7 mg L-1, 3.80 µg L-1 to 6.13 mg L-1, 135.59 µg L-1 -11.05 mg L-1, 0.05 µg L-1 to 1980.34 mg L-1, 0.012 to 3.78 µg L-1, and 1.12 µg L-1 to 2.32 µg L-1 of B, Co, Cu, Fe, Mn, Mo, and Zn, respectively, are found in tea infusion which are lower than the prescribed limit of micronutrients in drinking water by World Health Organization. Furthermore, micronutrient contents in tea infusion depend on infusion procedure as well as on the instrument used for analysis. The proportion of micronutrients found in different tea types are 1.0-88.9% for B, 10-60% for Co, 2.0-97.8% for Cu, 67.8-89.9% for Fe, 71.0-87.4% for Mn, 13.3-34% for Mo, and 34.9-83% for Zn. From the results, it can also be concluded that consumption of three cups of tea infusion per day does not have any adverse effect on human health with respect to the referred micronutrients rather got beneficial effects to human.

Study of nutritional value of dried tea leaves and infusions of black, green and white teas from Chinese plantations

Background: The processing of tea leaves determines the contents of bioactive ingredients, hence it should be expected that each variety of tea, black, red or green, will represent a different package of compounds of physiological importance. Taste and aroma, as well as price and brand are the main factors impacting consumers' preferences with regard to tea of their choice; on the other hand consumers less frequently pay attention to the chemical composition and nutritional value of tea. Objective: The purpose of the study was assessment of the nutritional value of black, green and white high-quality tea leaf from Chinese plantations based on the chemical composition of the dried leaves as well as minerals and caffeine content in tea infusions. Material and methods: The research material included 18 high-quality loose-leaf teas produced at Chinese plantations, imported to Poland, and purchased in an online store. The analyses included examination of the dried tea leaves for their chemical composition (contents of water, protein, volatile substances and ash) and assessment of selected minerals and caffeine contents in the tea infusions. Results: High-quality Chinese green teas were found with the most valuable composition of minerals, i.e. the highest contents of Zn, Mn, Mg, K, Ca and Al and the highest contents of protein in comparison to the other products. Chinese black teas had the highest contents of total ash and caffeine and white teas were characterized with high content of volatile substances, similar to the black teas, and the highest content of water and the lowest content of total ash. Conclusions: The three types of tea brews examined in the present study, in particular green tea beverages, significantly enhance the organism's mineral balance by providing valuable elements

Solid-phase purification and extraction for the determination of trace neonicotinoid pesticides in tea infusion.

An analytical protocol that includes solid-phase purification and extraction is successfully developed for the determination of trace neonicotinoid pesticides in tea infusion. The method consists of a purification on amino-functionalized mesoporous silica SBA-15 followed by a solid-phase extraction based on graphene oxide before ultra high performance liquid chromatography with tandem mass spectrometry analysis. Parameters that significantly affected the extraction of the neonicotinoids onto graphene oxide, such as the amount of adsorbent, extraction time, pH, elution solvent, etc. were optimized. The amino-functionalized mesoporous silica SBA-15 has been proved to be an efficient adsorbent for removal of polyphenols especially catechins from tea infusion. Graphene oxide exhibits a very rapid adsorption rate (within 10 min) and high adsorption capacities for neonicotinoids at low initial concentration (0.01-0.5 mg/L). The analysis method gave a good determination coefficient (r(2) > 0.99) for each pesticide and high recoveries in the range of 72.2-95.0%. Powder X-ray diffraction, Raman spectroscopy, transmission electron microscopy, and UV-vis spectroscopy were utilized to identify the structure and morphology of graphene oxide. The adsorption driving force of neonicotinoids on graphene oxide mainly depends on π-π electron donor-acceptor interaction and electrostatic interaction.

Voltammetric determination of polyphenolic content as rosmarinic acid equivalent in tea samples using pencil graphite electrodes.

The quasi-reversible, diffusion controlled behavior of rosmarinic acid (RA) on a disposable pencil graphite electrode (PGE) was established by cyclic voltammetry. Using the anodic oxidation peak presented by RA on the PGE a differential pulse voltammetric (DPV) method was developed for the quantitative determination of RA. The linear range was 10(-8) - 10(-5) M RA and the detection and quantification limits were 7.93 × 10(-9) M and 2.64 × 10(-8) M RA, respectively. The applicability of the developed method was tested by recovery studies and by the assessment of the total polyphenolic contents (TPCDPV) of green, white and black Turkish teas, which were found to be 40.74, 30.04 and 23.97 mg rosmarinic acid equivalent/g dry tea, respectively. These results were in good agreement with those obtained by the Folin-Ciocalteu method. The developed method is a sensitive and cheap tool for the rapid and precise evaluation of TPCDPV of tea samples.

Assessment of carcinogenic and non-carcinogenic risk of exposure to potentially toxic elements in tea infusions: Determination by ICP-OES and multivariate statistical data analysis.

BACKGROUND: The perennial evergreen tea (Camellia sinensis) plant is one of the most popular nonalcoholic drinks in the world. Fertilizers and industrial, agricultural, and municipal activities are the usual drivers of soil contamination, contaminating tea plants with potentially toxic elements (PTEs). These elements might potentially accumulate to larger amounts in the leaves of plants after being taken up from the soil. Thus, frequent monitoring of these elements is critically important. METHODS: The present study intended to determine PTEs (Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd, and Pb) in both tea leaves and infusions using ICP-OES. Various multivariate data analysis methods such as principal component analysis (PCA) and hierarchical cluster analysis (HCA) were employed to elucidate the potential sources of PTEs contamination, whether from anthropogenic activities or natural origins. Additionally, Pearson's correlation coefficient (PCC) was calculated to assess the relationships between the variables under study. RESULTS: The mean contents (mg/L) of all studied elements in tea infusions decreased in order Mn (150.59 ±â€¯1.66) > Fe (11.39 ±â€¯0.99) > Zn (6.62 ±â€¯0.89) > Cu (5.86 ±â€¯0.62) > Co (3.25 ±â€¯0.64) > Ni (1.69 ±â€¯0.23) > Pb (1.08 ±â€¯0.16) > Cr (0.57 ±â€¯0.09) > Cd (0.46 ±â€¯0.09) > Al (0.05 ±â€¯0.008), indicating that Mn exhibits the highest abundance. The mean concentration trend in tea leaf samples mirrored that of infusions, albeit with higher concentrations of PTEs in the former. The tolerable dietary intake (TDI) value for Ni and provisional tolerable monthly intake (PTMI) value for Cd surpassed the standards set by the WHO and EFSA. Calculated hazard index (HI < 1) and cumulative cancer risk (CCR) values suggest negligible exposure risk. CONCLUSION: Elevated levels of PTEs in commonly consumed tea products concern the public and regulatory agencies.

Simple and sensitive determination of Cr (III), Cu (II) and Pb (II) in tea infusions using AgNPs-modified resin combined with laser-induced breakdown spectroscopy.

The detection of heavy metals in tea infusions is important because of the potential health risks associated with their consumption. Existing highly sensitive detection methods pose challenges because they are complicated and time-consuming. In this study, we developed an innovative and simple method using Ag nanoparticles-modified resin (AgNPs-MR) for pre-enrichment prior to laser-induced breakdown spectroscopy for the simultaneous analysis of Cr (III), Cu (II), and Pb (II) in tea infusions. Signal enhancement using AgNPs-MR resulted in amplification with limits of detection of 0.22 µg L-1 for Cr (III), 0.33 µg L-1 for Cu (II), and 1.25 µg L-1 for Pb (II). Quantitative analyses of these ions in infusions of black tea from various brands yielded recoveries ranging from 83.3% to 114.5%. This method is effective as a direct and highly sensitive technique for precisely quantifying trace concentrations of heavy metals in tea infusions.

Reducing microplastics in tea infusions released from filter bags by pre-washing method: Quantitative evidences based on Raman imaging and Py-GC/MS.

Microplastics released from plastic-based filter bags during tea brewing have attracted widespread attention. Laser confocal micro-Raman and direct classical least squares were used to identify and estimate micron-sized microplastics. Characteristic peaks from pyrolysis-gas chromatography/mass spectrometry of polyethylene terephthalate, polypropylene, and nylon 6 were selected to construct curves for quantification submicron-sized microplastics. The results showed that microplastics released from tea bags in the tea infusions ranged from 80 to 1288 pieces (micron-sized) and 0 to 63.755 µg (submicron-sized) per filter bag. Nylon 6 woven tea bags released far fewer microplastics than nonwoven filter bags. In particular, a simple strategy of three pre-washes with room temperature water significantly reduced microplastic residues with removal rates of 76 %-94 % (micron-sized) and 80 %-87 % (submicron-sized), respectively. The developed assay can be used for the quantitative evaluation of microplastics in tea infusions, and the pre-washing reduced the risk of human exposure to microplastics during tea consumption.

Correlations of kratom (Mitragyna speciosa Korth.) tea bag preparations and reported pharmacological effects.

ETHNOPHARMACOLOGICAL RELEVANCE: The use of herbal tea infusions is widespread in ethnomedicine throughout the world. One such ethnobotanical is kratom (Mitragyna speciosa Korth., Rubiaceae) which has gained considerable interest as an herbal supplement in recent years in the West beyond its native Southeast Asia. Traditional, kratom leaves are either chewed fresh or made into a tea infusion to treat fatigue, pain, or diarrhea. However, dried kratom leaf powder and hydroalcoholic extracts are more commonly used in Western countries, raising the question of exposure to kratom alkaloids and related effects. AIM OF THE STUDY: A specific kratom tea bag product was analyzed for mitragynine content using tea infusion preparation and methanolic extraction. Consumers of both the tea bag product and other kratom products completed an online anonymous survey to determine demographics, kratom use patterns, and self-reported beneficial and detrimental effects. MATERIALS AND METHODS: Kratom tea bag samples were extracted using pH-adjusted water or methanol and analyzed using an established LC-QTOF method. A modified kratom survey was distributed to consumers of the kratom tea bag products and other kratom products over a 14-month period. RESULTS: Tea infusion extraction of tea bag samples resulted in lower mitragynine levels (0.062-0.131% (w/w)) compared to methanolic extraction (0.485-0.616% (w/w)). Kratom tea bag consumers did report similar, although often milder beneficial effects compared to consumers using other kratom products. Overall self-reported health was better among kratom tea bag consumers whereas improvement of a diagnosed medical condition was less in tea bag consumers compared to those using other kratom products. CONCLUSIONS: Traditional tea infusions of Mitragyna speciosa dried leaves provide benefits to consumers despite substantially lower mitragynine content. These effects may be less pronounced but indicate that tea infusions provide a potentially safer formulation compared to more concentrated products.