Purple tea

Nitrogen, boron co-doped carbon quantum dots (gCQDs), and a coloration probe (PPD-NPs) with response to cobalt ions (Co2+ ) were prepared by using 4-hydroxyphenylboric acid as the common precursor, with ethylenediamine and p-phenylenediamine (PPD) adopted as nitrogen-doped reagents, respectively. A noticeable brown-to-purple color change can be observed with the addition of Co2+ , and a broad absorption band emerges at 535 nm. At the same time, gCQDs, which is introduced as the fluorescence signal source, will be significantly quenched due to the enhanced inner filtration effect, induced by the overlap between the emission spectrum of gCQDs and the emerging absorption band...

BACKGROUND: BAHD acyltransferases are among the largest metabolic protein domain families in the genomes of terrestrial plants and play important roles in plant growth and development, aroma formation, and biotic and abiotic stress responses. Little is known about the BAHDs in the tea plant, a cash crop rich in secondary metabolites. RESULTS: In this study, 112 BAHD genes (CsBAHD01-CsBAHD112) were identified from the tea plant genome, with 85% (98/112) unevenly distributed across the 15 chromosomes...

The choice of tea utensils used for brewing significantly impacts the sensory and chemical attributes of tea. In order to assess the influence of various tea sets on the flavor and chemical composition of different tea varieties, a combination of sensory evaluation and high-performance liquid chromatography was employed. The results showed that the content of amino acids in the tea liquid brewed with tin tea utensils was relatively higher, which could exhibit freshness in taste, thus suitable for brewing green tea and white tea...

This study aimed to obtain an anthocyanin extract from the purple leaves of Camellia sinensis cv. Zijuan using a sustainable, non-toxic, and low-cost solid-liquid extraction, employing an aqueous citric acid solution (0.2 mol/L) as the extracting solvent, and to evaluate its chemical stability at different pH values, as well as its in vitro antioxidant properties in chemical and biological terms. The phenolic composition, in vitro antioxidant activity, and the stability of anthocyanins against pH, temperature, and light of the crude extract (CE) were evaluated, as well as the phenolic composition and bioactivity in the crude lyophilised extract (CLE)...

The high-level toxic effects of organophosphate (OP) nerve agents severely threaten national security and public health. Generating trustworthy, accurate methods for quickly identifying these poisonous chemicals is urgently necessary. In this study, we have presented an azine-based colorimetric sensor (HBD) for the highly sensitive and selective identification of poisonous sarin gas surrogate diethylchlorophosphate (DCP). Our introduced sensor shows a purple color in contact with DCP, which is fully reversible upon the addition of triethylamine (TEA)...

Tea is a popular beverage with characteristic functional and flavor qualities, known to be rich in bioactive metabolites such as tea polyphenols and theanine. Recently, tea varieties with variations in leaf color have been widely used in agriculture production due to their potential advantages in terms of tea quality. Numerous studies have used genome, transcriptome, metabolome, proteome, and lipidome methods to uncover the causes of leaf color variations and investigate their impacts on the accumulation of crucial bioactive metabolites in tea plants...

BACKGROUND: Adinandra nitida , commonly known as Shiya tea, is a healthcare drink enriched in several phenolic acids and flavonoids, with a purple-red leaf variety possessing a unique flavor and a higher economic value. However, the mechanisms underlying leaf coloration and senescence discoloration remain unknown. METHODS: Here, we compared both varieties of A. nitida (purple-red leaf, RL, and green leaf, GL) at two stages of development. To make sure the difference in leaf color in these four groups, several indexes, leaf colorimetric differences, H2O2 content in leaf cells, and antioxidant enzymes activities (superoxide dismutase (SOD), catalase (CAT)) were measured...

Root rot is an important disease of tea plants owing to its unobvious early symptoms and permanent damage (Huu et al. 2016). In 2019, 5% of tea plants displayed symptoms consistent with root rot in a tea plantation (28°09'N, 113°13'E) located in Changsha city, Hunan province of China. The symptoms of the diseased tea plants ranged from wilting leaves to entirely dead. The roots had black lesions and rot typical of this disease. Symptomatic roots were collected, washed with water and disinfected with 75% ethanol, then cut into pieces and sterilized with 0...

To elucidate the molecular mechanisms underlying the differential metabolism of albino (white), green, and purple pericarp coloration, biochemical profiling and transcriptome sequencing analyses were performed on three different tea pericarps, Zhongbaiyihao ( Camellia sinensis L. var. Zhongbai), Jinxuan ( Camellia sinensis L. var. Jinxuan), and Baitangziya ( Camellia sinensis L. var. Baitang). Results of biochemical analysis revealed that low chlorophyll content and low chlorophyll/carotene ratio may be the biochemical basis for albino characteristics in the 'Zhongbaiyihao' pericarp...

Tea plants (Camellia sinensis) typically contain high-flavonoid phytochemicals like catechins. Recently, new tea cultivars with unique purple-colored leaves have gained attention. These purple tea cultivars are enriched with anthocyanin, which provides an interesting perspective for studying the metabolic flux of the flavonoid pathway. An increasing number of studies are focusing on the leaf color formation of purple tea and this review aims to summarize the latest progress made on the composition and accumulation of anthocyanins in tea plants...

The tea plant (Camellia sinensis (L.) O. Kuntze) is a popular non-alcoholic beverage crop worldwide. The tea market in South Korea is projected to increase annually by 4.59% (Statista, 2022). Boseong, Hadong, and Jeju Island are the main tea-growing regions in South Korea. Anthracnose is one of the major diseases of tea plants and is responsible for substantial yield loss and poor tea quality. In 2021, anthracnose of tea (disease incidence of 30%) was observed in a garden (33°28'45.5"N 126°42'02.2"E) at Jeju Island, where the Yabukita cultivar has been cultivated...

ETHNOPHARMACOLOGICAL RELEVANCE: Tea (Camellia sinensis) has been consumed for centuries as traditional medicine for various diseases, including diabetes. The mechanism of action of many traditional medicines, including tea, often requires elucidation. Purple tea is a natural mutant of Camellia sinensis, grown in China and Kenya, and is rich in anthocyanins and ellagitannins. AIM OF THE STUDY: Here we aimed to determine whether commercial green and purple teas are a source of ellagitannins and whether green and purple teas, purple tea ellagitannins and their metabolites urolithins have antidiabetic activity...

There is increasing interest in the production and consumption of tea ( Camellia sinensis L.) processed from purple-leaved cultivar due to their high anthocyanin content and health benefits. However, how and why seasonal changes affect anthocyanin accumulation in young tea leaves still remains obscured. In this study, anthocyanin and abscisic acid (ABA) contents in young leaves of Zifuxing 1 (ZFX1), a cultivar with new shoots turning to purple in Wuyi Mountain, a key tea production region in China, were monitored over four seasons...

Camellia sinensis var. assamica cv. Zijuan (purple tea) is known for its content of anthocyanins, flavan-3-ols, and bioactivities. This study aimed to verify the influence of solvent polarity, in a solid-liquid extraction, on the content of phenolic compounds and chlorophylls, instrumental color, and antioxidant activity. Different proportions of water and ethanol (0:100, 25:75, 50:50, 75:25, and 100:0 v/v) were used for extraction. The results showed that the hydroalcoholic extract (75 % ethanol + 25 % water) had the highest contents of total flavonoids, total anthocyanins, chlorophyll A, and total carotenoids, as well as presenting the highest color intensity, proportion of yellow pigments, and antioxidant activity (total reducing capacity and scavenging of the DPPH free radical)...

Characteristic metabolites including tea polyphenols, amino acids, catechins, caffeine, sugars and anthocyanins were fully analyzed by high performance liquid chromatography (HPLC), gas chromatography tandem mass spectrometry (GC-MS) and ultra-high performance liquid chromatography (UHPLC)-ESI-tandem mass spectrometry (MS/MS), and showed significant differences among Zijuan tea from different plantations in Yunnan province (YN-ZJ), Qijiang (QJ-ZJ) and Ersheng (ES-ZJ) district, China, indicating that Zijuan is significantly influenced by growth conditions...

A variety of the classic green tea plant, Camellia sinensis , was developed and is exclusive to Kenya. Due to high content of anthocyanin polyphenols in its leaves, the beverage obtained from this variety is purple in color and is the origin of the name purple tea. This work had two main purposes. The first one was to identify and quantify the major anthocyanin polyphenols in a hot water aqueous extract of the purple tea leaves. The second one was to test the hypothesis if this extract is capable of inhibiting triglyceride absorption considering that anthocyanin polyphenolics have been frequently associated to antilipidemic effects...

Tea (Camellia sinensis (L.) O. Kuntze), a perennial evergreen shrub, is one of the most important cash crops in China. In September 2021, leaf spot symptoms were observed on approximately 30% of tea plants in a 2 ha commercial field of Lushan (29°33'0" N, 115°58'48" E), Jiangxi Province, China. The symptoms initially appeared as small, gray lesions, and later became larger (10-15 mm in diameter) circular to irregular spots with light brown centers and gray borders. To isolate the pathogen, small pieces (3×3 mm) cut from the margins of lesions were sterilized with 75% ethanol for 10 s, 0...

Flavonoids and caffeine are the major secondary metabolites with beneficial bioactivity for human health in tea plants, and their biosynthesis pathway and regulatory networks have been well-deciphered. However, the accumulation traits of flavonoids and caffeine in different tea cultivars was insufficient in investigation. In this study, metabolomic and transcriptomic analyses were performed to investigate the differences of flavonoids and caffeine accumulation and regulation between Chinese varieties, including the 'BTSC' group with green leaf, the 'BTZY' group with purple foliage, and the 'MYC' group comprising Assam varieties with green leaf...

Flavonoids are rich in tea plants (Camellia sinensis), and responsible for the flavor and healthful benefits of tea beverage. The anthocyanin levels in the purple tender shoots are higher than in the general green leaves of tea plant, which provide special materials to search metabolic mechanisms of flavonoid enrichment in plant. In this work, flavonoid differences between purple and green shoots from tea cultivars 'Zijuan' (ZJ) and 'Yunkang10' (YK-10) were investigated through metabolomic analysis, and mechanisms for their difference were surveyed by comparative transcriptomic and proteomic analysis...

This integrative review aims to identify the main flavonoids present in some species of the Myrtaceae family. Studies published between 2016 and 2022 were selected, specifically those which were fully available and written in Portuguese, English, or Spanish, and which were related to the fruits araçá ( Psidium cattleianum ), cambuí ( Myrciaria floribunda ), gabiroba ( Campomanesia xanthocarpa ), jabuticaba ( Plinia cauliflora ), and jambolan ( Syzygium cumini ). Scientific studies were gathered and selected in Google Scholar, Scielo, and Science Direct indexed databases, out of which 14 were about araçá, 7 concerned cambuí, 4 were about gabiroba, 29 were related to jabuticaba, and 33 concerned jambolan, when we observed the pre-established inclusion criteria...