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Changes in Phenolic Compounds Profiles in Tea Extracts and the Composition of these Phenolic Compounds in Yogurt

Shori AB, Muniandy P, Baba AS

Recent Pat Food Nutr Agric, 2021;12(1):36-44.
PMID: 33231153 DOI: 10.2174/2212798411999201123205022

BACKGROUND: Green, white, and black tea water extracts are rich in phenolic compounds.
OBJECTIVE: The changes in phenolic compound profiles of green, white, and black tea (GT, WT, & BT respectively) water extracts and their respective yogurt were investigated.
METHODS: Three types of yogurt with tea water extracts were prepared, and the phenolic compound profiles were analyzed using the liquid chromatography-mass spectrometry (LC-MS) method.
RESULTS: The present data found that flavonol glycosides such as kaempferol-3-rutinoside and quercetin-rhamnosylgalactoside or rutinoside were present in WT extract, whereas catechin derivatives such as gallocatechin (GC) and epigallocatechin (EGC) were present in GT extract. Moreover, theaflavin-3-O-gallate was observed in BT extract. Many of the catechin and its derivatives detected in the tea extracts were not identified in the tea yogurt samples. However, new phenolic compounds were present in GT-yogurt (i.e., kaempferol-3-rutinoside and quinic acid conjugate) but absent in GT extract.
CONCLUSION: GT, WT, & BT extracts could be used to enriched-yogurt with phenolic compounds, which may have antioxidant properties.

Matched MeSH terms: Camellia sinensis/chemistry*
Rapid tea catechins and caffeine determination by HPLC using microwave-assisted extraction and silica monolithic column

Rahim AA, Nofrizal S, Saad B

Food Chem, 2014 Mar 15;147:262-8.
PMID: 24206716 DOI: 10.1016/j.foodchem.2013.09.131

A rapid reversed-phase high performance liquid chromatographic method using a monolithic column for the determination of eight catechin monomers and caffeine was developed. Using a mobile phase of water:acetonitrile:methanol (83:6:11) at a flow rate of 1.4 mL min(-1), the catechins and caffeine were isocratically separated in about 7 min. The limits of detection and quantification were in the range of 0.11-0.29 and 0.33-0.87 mg L(-1), respectively. Satisfactory recoveries were obtained (94.2-105.2 ± 1.8%) for all samples when spiked at three concentrations (5, 40 and 70 mg L(-1)). In combination with microwave-assisted extraction (MAE), the method was applied to the determination of the catechins and caffeine in eleven tea samples (6 green, 3 black and 2 oolong teas). Relatively high levels of caffeine were found in black tea, but higher levels of the catechins, especially epigallocatechin gallate (EGCG) were found in green teas.

Matched MeSH terms: Camellia sinensis/chemistry*
A novel high throughput method based on the DPPH dry reagent array for determination of antioxidant activity

Musa KH, Abdullah A, Kuswandi B, Hidayat MA

Food Chem, 2013 Dec 15;141(4):4102-6.
PMID: 23993591 DOI: 10.1016/j.foodchem.2013.06.112

A stable chromogenic radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) is commonly used for the determination of antioxidant activity. In this paper, DPPH was dried into 96 well microplate to produce DPPH dry reagent array plate, based on which the highly sensitive and high throughput determination of antioxidant activities was achieved. The spectrophotometric characterization of the microplate containing dried or fresh DPPH free radicals was reported. The response of the DPPH dry reagent array towards different standard antioxidants was studied. The reaction for DPPH in fresh or dry reagent array with Trolox was reported and compared. The DPPH dry reagent array was used to study the antioxidant activity of banana, green tea, pink guava, and honeydew and the results were compared to the samples reacted with freshly prepared DPPH. The proposed method is comparable to the classical DPPH method, more convenient, simple to operate with minimal solvent required and excellent sensitivity.

Matched MeSH terms: Camellia sinensis/chemistry*
Fulltext Synthesis of silver nanoparticles by using tea leaf extract from Camellia sinensis

Loo YY, Chieng BW, Nishibuchi M, Radu S

Int J Nanomedicine, 2012;7:4263-7.
PMID: 22904632 DOI: 10.2147/IJN.S33344

The development of the biological synthesis of nanoparticles using microorganisms or plant extracts plays an important role in the field of nanotechnology as it is environmentally friendly and does not involve any harmful chemicals. In this study, the synthesis of silver nanoparticles using the leaves extract of Chinese tea from Camellia sinensis is reported. The synthesized nanoparticles were characterized using UV-vis spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and Fourier transform infrared (FTIR) spectroscopy. The XRD analysis shows that the synthesized silver nanoparticles are of face-centered cubic structure. Well-dispersed silver nanoparticles with an approximate size of 4 nm were observed in the TEM image. The application of the green synthesized nanoparticles can be used in many fields such as cosmetics, foods, and medicine.

Matched MeSH terms: Camellia sinensis/chemistry*
A note on (+)-catechin

Wiart C

Nutr Res, 2015 Jun;35(6):545.
PMID: 25957969 DOI: 10.1016/j.nutres.2015.04.014
Matched MeSH terms: Camellia sinensis/chemistry*
Changes in microbial diversity and volatile metabolites during the fermentation of Bulang pickled tea

Zhou J, Chen L, Foo HL, Cao Z, Lin Q

Food Chem, 2024 Nov 15;458:140293.
PMID: 38970959 DOI: 10.1016/j.foodchem.2024.140293

The present study aimed to determine microbial community, short-chain fatty acids (SCFAs), and volatilome of Bulang pickled tea during fermentation. Sequencing of 16S rRNA and ITS revealed that Bualng pickled tea was dominated by Lactobacillus plantarum, unclassified Enterobacteriaceae, unclassified Debaryomyces, Candida metapsilosis, Cladosporium sphaerospermum, and unclassified Aspergillus. The overall contents of SCFAs increased, with acetic acid showing the highest content. A total of 398 differential volatile metabolites were detected using differential metabolomics analysis. Out of these different volatile compounds, ten key volatile compounds including (Z)-4-heptenal, 1-(2-thienyl)-ethanone, 5-methyl-(E)-2-hepten-4-one, 2-ethoxy-3-methylpyrazine, p-cresol, 2-methoxy-phenol, ethy-4-methylvalerate, 3-ethyl-phenol, p-menthene-8-thiol, and 2-s-butyl-3-methoxypyrazinewere were screened based on odor activity value (OAV). The Spearman correlation analysis showed a high correlation of SCFAs and volatile compounds with microorganisms, especially L. plantarum and C. sphaerospermum. This study provided a theoretical basis for elucidating the flavor quality formation mechanism of Bulang pickled tea.

Matched MeSH terms: Camellia sinensis/chemistry
Phyto-enhanced remediation of soil co-contaminated with lead and diesel fuel using biowaste and Dracaena reflexa: A laboratory study

Dadrasnia A, Pariatamby A

Waste Manag Res, 2016 Mar;34(3):246-53.
PMID: 26675494 DOI: 10.1177/0734242X15621375

In phytoremediation of co-contaminated soil, the simultaneous and efficient remediation of multiple pollutants is a major challenge rather than the removal of pollutants. A laboratory-scale experiment was conducted to investigate the effect of 5% addition of each of three different organic waste amendments (tea leaves, soy cake, and potato skin) to enhance the phytoaccumulation of lead (60 mg kg(-1)) and diesel fuel (25,000 mg kg(-1)) in co-contaminated soil by Dracaena reflexa Lam for a period of 180 day. The highest rate of oil degradation was recorded in co-contaminated soil planted with D. reflexa and amended with soy cake (75%), followed by potato skin (52.8%) and tea leaves (50.6%). Although plants did not accumulate hydrocarbon from the contaminated soil, significant bioaccumulation of lead in the roots and stems of D. reflexa was observed. At the end of 180 days, 16.7 and 9.8 mg kg(-1) of lead in the stems and roots of D. reflexa were recorded, respectively, for the treatment with tea leaves. These findings demonstrate the potential of organic waste amendments in enhancing phytoremediation of oil and bioaccumulation of lead.

Matched MeSH terms: Camellia sinensis/chemistry
Molecular understanding of Epigallocatechin gallate (EGCG) in cardiovascular and metabolic diseases

Eng QY, Thanikachalam PV, Ramamurthy S

J Ethnopharmacol, 2018 Jan 10;210:296-310.
PMID: 28864169 DOI: 10.1016/j.jep.2017.08.035

ETHNOPHARMACOLOGICAL RELEVANCE: The compound epigallocatechin-3-gallate (EGCG), the major polyphenolic compound present in green tea [Camellia sinensis (Theaceae], has shown numerous cardiovascular health promoting activity through modulating various pathways. However, molecular understanding of the cardiovascular protective role of EGCG has not been reported.
AIM OF THE REVIEW: This review aims to compile the preclinical and clinical studies that had been done on EGCG to investigate its protective effect on cardiovascular and metabolic diseases in order to provide a systematic guidance for future research.
MATERIALS AND METHODS: Research papers related to EGCG were obtained from the major scientific databases, for example, Science direct, PubMed, NCBI, Springer and Google scholar, from 1995 to 2017.
RESULTS: EGCG was found to exhibit a wide range of therapeutic properties including anti-atherosclerosis, anti-cardiac hypertrophy, anti-myocardial infarction, anti-diabetes, anti-inflammatory and antioxidant. These therapeutic effects are mainly associated with the inhibition of LDL cholesterol (anti-atherosclerosis), inhibition of NF-κB (anti-cardiac hypertrophy), inhibition of MPO activity (anti-myocardial infarction), reduction in plasma glucose and glycated haemoglobin level (anti-diabetes), reduction of inflammatory markers (anti-inflammatory) and the inhibition of ROS generation (antioxidant).
CONCLUSION: EGCG shows different biological activities and in this review, a compilation of how this bioactive molecule plays its role in treating cardiovascular and metabolic diseases was discussed.

Matched MeSH terms: Camellia sinensis/chemistry
Exposure of a Dengue Vector to Tea and Its Waste: Survival, Developmental Consequences, and Significance for Pest Management

Dieng H, Tan Yusop NS, Kamal NN, Ahmad AH, Ghani IA, Abang F, et al.

J Agric Food Chem, 2016 May 11;64(18):3485-91.
PMID: 27115536 DOI: 10.1021/acs.jafc.6b01157

Dengue mosquitoes are evolving into a broader global public health menace, with relentless outbreaks and the rise in number of Zika virus disease cases as reminders of the continued hazard associated with Aedes vectors. The use of chemical insecticides-the principal strategy against mosquito vectors-has been greatly impeded due to the development of insecticide resistance and the shrinking spectrum of effective agents. Therefore, there is a pressing need for new chemistries for vector control. Tea contains hundreds of chemicals, and its waste, which has become a growing global environmental problem, is almost as rich in toxicants as green leaves. This paper presents the toxic and sublethal effects of different crude extracts of tea on Aedes albopictus. The survival rates of larvae exposed to tea extracts, especially fresh tea extract (FTE), were markedly lower than those in the control treatment group. In addition to this immediate toxicity against different developmental stages, the extracts tested caused a broad range of sublethal effects. The developmental time was clearly longer in containers with tea, especially in those with young larvae (YL) and FTE. Among the survivors, pupation success was reduced in containers with tea, which also produced low adult emergence rates with increasing tea concentration. The production of eggs tended to be reduced in females derived from the tea treatment groups. These indirect effects of tea extracts on Ae. albopictus exhibited different patterns according to the exposed larval stage. Taken together, these findings indicate that tea and its waste affect most key components of Ae. albopictus vectorial capacity and may be useful for dengue control. Reusing tea waste in vector control could also be a practical solution to the problems associated with its pollution.

Matched MeSH terms: Camellia sinensis/chemistry*