Catechin Content Research Articles

Variation of elastase, collagenase, tyrosinase enzyme inhibitory and antioxidant potential of different tea cultivars

Sri Lankan tea germplasm consists of over 600 accessions, and currently, 70 cultivars are recommended for commercial cultivation. However, the skin whitening and anti-aging effects of Sri Lankan tea cultivars/accessions have not been reported. In this study, tea leaves and black tea of fifteen tea cultivars were tested for their anti-oxidative and enzyme inhibitory potentials against elastase, collagenase, and tyrosinase enzymes for the first time. All samples were evaluated for their total polyphenol, caffeine, and individual catechin contents, and the results significantly differed among tea cultivars. The antioxidant potential of black tea and tea leaves significantly varied among the tea cultivars used. The enzyme inhibitory potential on tyrosinase, elastase, and collagenase inhibitory potential in black tea were varied among the tea cultivars, with the IC50 ranged from 208.82 ± 5.18 to ≥ 1200 ppm, 36.71 ± 6.38 to ≥ 600 ppm, and 786.31 ± 2.33 to ≥ 1300 ppm, respectively. None of the tested tea cultivars resulted in strong collagenase inhibitory potential. This study concludes that, among the tested tea cultivars, black tea manufactured using tea cultivars TRI 4004 and TRI 4049 and both tea leaves and black tea manufactured from TRI 4053, TRI 3017, and TRI 4061 exhibited remarkable anti-aging and skin-whitening properties. The findings of this study could be utilized for the selection of tea cultivars/accessions for the manufacture of speciality tea with functional properties and also to promote Sri Lankan tea in the global market.

The masking mechanism of catechin to the sweet taste of phloridzin

Our previous study speculated that decreased levels of catechin were associated with heightened sweetness in Camellia nanchuanica black tea (NCBT). In this study, we found that catechin has the capacity to obscure the sweet taste of phloridzin and verified the above speculation. To delve deeper into this masking effect, we examined various concentrations of catechin (cat-10cat) and phloridzin (phl-10phl), and revealed catechin (cat-10cat) significantly reduced the sweetness of 10phl. Therefore, catechin (cat-10cat) and 10phl combinations were selected to investigate the impact on sweet taste receptor cells. The results showed increasing concentrations of catechin inhibited the calcium signal of the phloridzin-catechin solution, attributing to lower stability of phloridzin and Taste 1 Receptor Member 3 (one subunit of sweet taste receptor proteins) after addition catechin. Finally, 10phl/10cat significantly activated the central and prefrontal regions generating more bitter tastes and negative emotions which also probably contributed to mask sweet tastes of phloridzin.

Classification of green tea and quantitative prediction of catechin content based on indicator displacement array sensors

Green tea, renowned for its health benefits and cultural significance, exhibits variations in quality and biochemical composition across different grades and varieties. Traditional quality assessment methods are often labour-intensive and time-consuming, rendering them impractical for rapid analysis. This study employed a sensitive indicator displacement array sensor along with supervised learning algorithms—Extreme learning machine, Support vector machine, Random forest, and Back propagation neural network—to accurately classify green tea varieties and grades, as well as predict catechin content. Sensor components were initially screened based on their responsiveness to epigallocatechin gallate, and subsequently developed using specific indicator-receptor combinations: Pyrocatechol Violet/Fe2+, Alizarin Red S/Phenylboronic Acid, and Bromopyrogallol Red/3-Nitrophenylboronic Acid. Validation was performed through monitoring changes in RGB values and UV–visible spectroscopy. Discrimination among Anji white tea grades was assessed using principal component analysis and further refined through supervised algorithms, achieving high accuracy rates, especially with Random forest and Extreme learning machine models, which excelled in both calibration and prediction sets. These methodologies were extended to classify ten green tea varieties, demonstrating robustness and high accuracy in a multiclass setting. Independent validation confirmed the models’ efficacy in-class differentiation, with most achieving an accuracy of over 90%. Moreover, the quantitative prediction of catechin content was enhanced using nonlinear models, specifically Support vector regression optimized with the Particle swarm optimization algorithm. These models exhibited superior performance compared to linear models, particularly in effectively predicting individual catechin levels. These findings highlight the potential of combining sensor technologies with supervised learning algorithms to enhance tea quality assessment and categorization, establishing a robust framework for future applications in tea quality control.

The investigation prospect application of alcohol-water extract of lingonberry as antimicrobial, anti-fungi and antioxidant pharmaceutical

Infection diseases is a worldwide important problem for medicine and pharmacy. Every year 13.7 million people die from bacterial infections in the world. Thus, the search of new compounds with antimicrobial and anti-fungi activity is topical for today. The object of the study was lingonberry leaf 60% extract. The content of phenylpropanoids derivatives was evaluated by spectrophotometric method of analysis, whereas organic acids by alkalimetric method; antioxidant power was found by potentiometric method; antibacterial and antifungal activity was assessed by the method of “wells”. According to the results of the study, it was shown that the lingonberry leaf extract is inferior to the green tea leaf extract in terms of the content of phenolic compounds, catechins, hydroxycinnamic and organic acids, but flavonoids dominate in the lingonberry extract. The study found that lingonberry leaf extract has a high level of antioxidant activity. When comparing the levels of antioxidant action of lingonberry extract with green tea extract and the «gold standard» – аepigallocatechin-3-O-gallate in one concentration of 0.03 mol/L, it was found that lingonberry extract had the best result. Escherichia coli bacteria was the most sensitive to the extract whereas Pseudomonas aeruginosa was the most resistant. This work shows that 60% ethanolic lingonberry leaf extract has potent antioxidant, antimicrobial and antifungal effects. According to the obtained results, it can be concluded that 60% V. vitis-idaea leaf extract is promising for the development of new antimicrobial, antifungal and antioxidant pharmaceutical.

Geographic based phenolic compound variations in South African Schinus molle L. peppercorns

Environmental conditions affect polyphenolic compounds in plants, and yet little is known about the response of Schinus molle peppercorns to geographical location. S molle is a folkloric pseudospice of Andean origin possessing multiple culinary and medicinal functions. This globally invasive species presents an immense multidimensional potential. Polyphenolic compounds were therefore profiled and quantified from pink peppercorns growing in 12 distinct locations in the Eastern and Western Cape provinces of South Africa using UPLC-QTOF-MS techniques. Eleven flavonoids were reported, including epigallocatechin gallate, +)-tephrorin B, astilbin, procyanidin B5, 4-benzyl-7-hydroxy-3-phenyl-2H-chromen-2-one, and isochamaejasmin which were reported for the first time in this species. Five phenolic acids, three glycosides, and tannins (theogallin (3-galloylquinic acid), digalloyl quinic acid, digalloylshikimic acid, β-glucogallin A and β-glucogallin B) were also revealed among others. PCA revealed a high composition of polyphenolic compounds in the Eastern in comparison to the Western Cape regions. Flavonoids were glaringly higher in winter rainfall receiving coastal regions. Consequently, the highest catechin content was 229% higher in the Eastern (1269.9 mg/kg) than the Western Cape (553.4 mg/kg). Furthermore, isochamaejasmin, the compound with possibly the highest concentration is reported in George (1741 mg/kg) and Gqeberha (2601.2 mg/kg) representing 149% differences between the two regions. Soil type alone did not conclusively appear to influence polyphenolic compound accumulation in this study. Elucidating the distribution of polyphenolic compounds in this species could open new insights for potential therapeutic, pharmaceutical, and agricultural applications including possibilities for new and improved organic drugs, and food product development.

Leucoanthocyanidin Reductase 3 (PaLAR3) Locus in Norway Spruce (Picea abies) and Its Link to Resistance Against Heterobasidion parviporum

ABSTRACTHeterobasidion parviporum is a fungal pathogen that is drastically damaging Norway spruce (Picea abies) in Europe. The infections will result in root and stem rot, causing significant economic losses for forest owners. Previous studies have shown that the PaLAR3 gene, which encodes the leucoanthocyanidin reductase enzyme, can increase resistance to H. parviporum in Norway spruce. The presence of the B allele at the PaLAR3 locus has been associated with higher (+)‐catechin concentrations and increased enzyme production in inoculation experiments, resulting in inhibited pathogen growth. The control of H. parviporum involves a multifaceted approach, including silvicultural and sustainable forestry practices, genetic resistance and chemical/biological control. In this study, we determined the PaLAR3 genotypes in a representative sample of Norway spruce breeding materials from southern Finland and examined their effect on necrosis caused by H. parviporum in spruce stems. The results showed that the homozygous PaLAR3BB genotype was present in only 9% of the trees. However, the necrotic area interacted with homozygous PaLAR3BB under low‐water treatment. These findings support the idea that the PaLAR3 locus may be a valuable marker for identifying P. abies resistance to different strains of Heterobasidion parviporum.

Evaluation of Polyphenol Profile from Citrus Peel Obtained by Natural Deep Eutectic Solvent/Ultrasound Extraction

Citrus fruits are widely consumed worldwide; however, one of their primary uses is juice production, resulting in over 40 million tons of agro-industrial waste. Citrus peel is the main agro-industrial by-product in citrus production. In recent years, secondary metabolites of interest, mainly polyphenols such as hesperidin, have been identified in citrus peels. Currently, green alternatives like natural deep eutectic solvents (NADES) based on choline chloride and glucose (Glu), combined with ultrasound-assisted extraction, are studied to obtain polyphenol-rich extracts with potential health applications. This study aims to evaluate the effect of: (1) molar ratios (MR) of 1:0.5, 1:1 or 1:2 mol/mol of choline chloride (ChCl):glucose (Glu); (2) the percentage of added water (WA: 50, 60 or 70%) to NADES; and (3) different citrus peels of Citrus aurantium (bitter orange), Citrus sinensis (sweet orange), and Citrus limon (lemon) used for extraction, on polyphenol profiles, total polyphenol content (TPC), and antioxidant capacity (Ax) of the extracts. The extracts were analyzed using ultra-performance liquid chromatography (UPLC) and evaluated using the Folin–Ciocalteu method for TPC and DPPH assay for quantifying AC. A factorial experimental design 33 was implemented. The extract obtained with an MR of 1:1 (ChCl:Glu) from Citrus aurantium peel exhibited the highest concentration of hesperidin (2003.37 ± 10.91 mg/100 g dry mass), whereas an MR of 1:2 (ChCl:Glu) exhibited the highest concentration of neohesperidin (1045.94 ± 1.27 mg/100 g dry mass), both using 60% WA. This extract also showed the highest antioxidant capacity, achieving 100% inhibition. On the other hand, the highest concentration of total phenolic content (TPC) (96.23 ± 0.83 mg GAE/100 g dry mass) was obtained using C. aurantium peel with an MR of 1:0.5 (ChCl:Glu) and 60% WA. The extracts also presented high concentrations of rutin and catechin. These findings highlight the potential of revalorizing citrus peels, particularly Citrus aurantium, and their extracts obtained with NADES for possible health applications.

Analysis of chemical composition, antimicrobial, antioxidant activities of pomegranate fruit thick and green tea leaf extracts

Infection diseases is a worldwide important problem for medicine and pharmacy. The purpose of this work was to study and compare phytochemical composition, antimicrobial, antioxidant potential of pomegranate fruit thick and green tea leaf liquid extracts. The quantification of biologically active substances (BAS) was performed using spectrophotometric, titrimetric, and HPLC analysis methods. Antioxidant activity was measured through a potentiometric method, while antimicrobial and antifungal effects were assessed using the well method and determining the minimum inhibition concentration. The total content of phenolic compounds was 0.40 and 10.10%, organic acids – 5.80 and 1.60% for pomegranate fruit thick and green tea leaf extract. The total content of catechins in the green tea leaf extract was 10500.0 mg/100 g, where epicatechin-3-O-gallate was dominated (3730.0±2.00 mg/100 g). The total content of anthocyanins in the pomegranate fruit thick extract was 107.10 mg/100 g, where cyanidin-3-O-glucoside was dominated (41.74 ± 0.10 mg/100 g), whereas delphinidin-3-O-glucoside had a lowest content (4.99 ± 0.10 mg/100 g). Both extracts possessed a high antioxidant potential, and effective antimicrobial effects. The antioxidant, antimicrobial activity of pomegranate fruit extract was higher than green tea leaf extract. In addition, we assumed that anthocyanins had higher antioxidant, antimicrobial properties than catechins. These findings would promote application of pomegranate fruits extract as pharmaceuticals and nutraceuticals.

Catechin as a functional additive in electrospun PCL/gelatin/nHA nanocomposite fibers for tissue engineering applications

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

The shaping of milk-flavored white tea: More than a change in appearance

Tea's popularity and flavor are influenced by factors like cultivation and processing methods and shaping techniques also have an impact on tea flavor. This study employed targeted metabolomics and chemometrics to investigate how shaping techniques affect the flavor of milk-flavored white tea (MFWT). The results showed that the tea cake sample with the shortest pressing time (Y90) has the highest amino acid content and milky aroma intensity. There were variations in amino acids, catechins, and soluble sugars among MFWT samples with different shaping techniques. The total contents of amino acids and catechins in tea cake sample (Y90) were significantly lower than those in the loose tea sample (SC) and bundle-like tea sample (SG), while the total sugar content was significantly higher than that in SC (P<0.05). Additionally, the content of volatiles presenting milky aroma (VIP&OAV>1) in Y90 remained lower relative to SC and SG (P<0.05), but the proportion was not different from that in SC and SG, minimally affecting the overall flavor. The short-time pressing method might be suitable for mass production of MFWT. These findings provide insights into improving the tightness of the appearance of MFWT with minimal impact on tea flavor.

The Effect of Maturity Stage on Polyphenolic Composition, Antioxidant and Anti-Tyrosinase Activities of Ficus rubiginosa Desf. ex Vent. Extracts.

Ficus spp. are often used as food and in traditional medicine, and their biological activities as anti-inflammatory and diuretic, for wound healing, and as antimicrobial agents have been largely reviewed. The aim of this work was to investigate the polyphenol content and the antioxidant and anti-tyrosinase properties of the extracts from F. rubiginosa, a very poorly explored Ficus species. For this purpose, F. rubiginosa leaves were collected at three different maturity stages (H1, H2, and H3), and the environmentally sustainable methanolic extracts were evaluated for the total phenolic content (TPC), total flavonoid content (TFC), and total catechins content (TCC). The polyphenolic profile was studied using HPLC-UV/DAD and UHPLC-MS, and the antioxidant activity was determined in vitro using DPPH, FRAP, and ABTS assays. The study showed that the H2 extract had higher TPC and TFC values (113.50 mg GA/g and 43.27 mg QE/g, respectively) and significant antioxidant activity. Therefore, the H2 extract was selected to study the anti-tyrosinase activity. The results also showed that H2 was able to bind and inhibit tyrosinase, with rutin being the compound responsible for the measured activity on the enzyme.

Arbuscular mycorrhizal fungi enhance nitrogen assimilation and drought adaptability in tea plants by promoting amino acid accumulation.

The development and quality of tea plants (Camellia sinensis (L.) O. Ktze.) are greatly hampered by drought stress (DS), which affects them in a number of ways, including by interfering with their metabolism of nitrogen (N). Arbuscular mycorrhizal fungi (AMF) are known to enhance water and nutrient absorption in plants, but their specific effects on tea plant N metabolism under DS and the associated regulatory mechanisms remain unclear. This study aimed to evaluate the impact of Claroideoglomus etunicatum inoculation on N assimilation in tea plants (C. sinensis cv. Fuding Dabaicha) under well-watered (WW) and DS conditions, and to explore potential molecular mechanisms. After 8 weeks of DS treatment, root mycorrhizal colonization was significantly inhibited, and the biomass of tea shoots and roots, as well as the contents of various amino acids (AAs) were reduced. However, AMF inoculation significantly increased the contents of tea polyphenols and catechins in leaves by 13.74%-36.90% under both WW and DS conditions. Additionally, mycorrhizal colonization notably increased N content by 12.65%-35.70%, various AAs by 11.88%-325.42%, and enzymatic activities associated with N metabolism by 3.80%-147.62% in both leaves and roots. Gene expression analysis revealed a universal upregulation of N assimilation-related genes (CsAMT1;2, CsAMT3;1, CsGS1, CsNADH-GOGAT, CsTS2, CsGGT1, and CsADC) in AMF-colonized tea roots, regardless of water status. Under DS condition, AMF inoculation significantly upregulated the expressions of CsNRT1;2, CsNRT1;5, CsNRT2;5, CsNR, CsGS1, CsGDH1, CsGDH2, CsTS2, CsGGT1, CsGGT3, and CsSAMDC in tea leaves. These findings suggest that AMF improved tea plant adaptability to DS by enhancing N absorption and assimilation, accompanied by the synthesis and accumulation of various AAs, such as Glu, Gln, Asp, Lys, Arg, GABA and Pro. This is achieved through the upregulation of N metabolism-related genes and the activation of related enzymes in tea plants under DS condition. These findings provide valuable insights into the role of AMF in regulating tea plant N metabolism and enhancing stress tolerance.

Accurate Prediction of Tea Catechin Content with Near-Infrared Spectroscopy by Deep Learning Based on Channel and Spatial Attention Mechanisms

Accurate Prediction of Tea Catechin Content with Near-Infrared Spectroscopy by Deep Learning Based on Channel and Spatial Attention Mechanisms

Tea Consumption and Human Health: A Review of Benefits and Impact on Chronic Disease Prevention

Tea, derived from the Camellia sinensis plant, is a globally consumed beverage with a rich history spanning thousands of years. Its cultural and social significance is evident in numerous societies, from ancient China to modern Western cultures. Historically revered for its potential health benefits, tea has gained scientific support for its role in chronic disease prevention. This review examines the historical and cultural importance of tea, its bioactive compounds, and its impact on health. Key areas include cancer prevention, cardiovascular health, metabolic syndrome management, and neuroprotection. Green tea, particularly noted for its high concentration of catechins, has been extensively studied for its health-promoting effects, including antioxidant, anti-inflammatory, and cancer-preventive properties. Black, oolong, and white teas each offer distinct benefits due to their unique compositions. Despite the promising evidence, potential risks such as caffeine sensitivity and reduced iron absorption should be considered. Future research is needed to further elucidate the mechanisms underlying tea’s health benefits and to explore its efficacy across diverse populations. Keywords: Tea, Camellia sinensis, Health Benefits, Cancer Prevention, Cardiovascular Health, Metabolic Syndrome.

Comparison of Waste from Different Types of Tea to Dried Butterfly Pea Flower

At present, the bioactive compounds of teas are well established and there are more attempts to apply tea as a functional drink or food supplement. In addition, during tea processing, tea waste, including broken tea leaves, buds and stems, is generated and disposed to the environment. The present study aimed to compare the quality of tea waste generated in full fermentation (raw Pu-erh tea, ripen Pu-erh tea and Anhua dark tea) and non-fermentation (green tea) processings in comparison with dried butterfly pea flower (DBPF) (non-Camellia sinensis). The results showed that total flavonoid (TFC) was found to be the highest in raw Pu-erh tea at 474.470 ± 47.173 mg RE/g, followed by ripened Pu-erh tea, green tea, Anhua dark tea, and DBPF, respectively. Similarly, raw Pu-erh tea also had the highest total phenolic (TPC) at 608.090 ± 2.795 mg GAE/g, followed by green tea, Anhua dark tea, ripen Pu-erh tea, and DBPF, respectively. On the other hand, total polysaccharides (TPS) content in DBPF was the highest among samples, whereas that of raw Pu-erh tea was the lowest. According to the HPLC analysis, caffeine (CF) was the major catechin found in all types of tea waste and the total catechin content was in the order of raw Pu-erh &gt; ripen Pu-erh tea &gt; green tea &gt; Anhua dark tea which was in agreement with the TPC results. However, the types of catechin were different in each sample. It is noteworthy that there was no CF in DBPF, and major catechin found in DBPF was catechin gallate. Likewise, antioxidant ability determined by DPPH was the most superior in raw Pu-erh tea, followed by green tea, ripen Pu-erh tea, Anhua dark tea and DBPF, respectively. ORAC antioxidant capacity was highest in the green tea, while that in raw Pu-erh tea, ripen Pu-erh tea and Anhua dark tea was lower but not significantly different, as expected, DBPF possessed the lowest ORAC antioxidant capacity. Finally, it can be said that the potential for tea waste to be a valuable source of antioxidants varies depending on the tea processing, and the plant variety also had an impact on the characteristics of the tea samples.

Grape seed phenolic extracts encapsulation in polymeric nanoparticles: Characterization and in vitro evaluation against skin melanoma

Nanocarrier platforms encapsulating plant-based natural extracts have emerged as an attractive tool to increase the safety and stability of phytomedicines and nutraceuticals. In this study, phenolic fractions were extracted from grape seed waste, spray dried, and characterized. Grape seed extracts (GSE) of Marselan, a red international variety, and Obeidi, a Lebanese autochthonous white variety, had a total phenolic content (TPC) of 301 and 206 mg gallic acid equivalents (GAE)/g of dry matter, respectively, along with a high content of catechins, gallic acid, epicatechins, caffeic acid, syringic acid, and protocatechuic acid. A nanocarrier formulation was developed using poly(ethylene glycol)-b-poly(lactide-co-glycolide) (PEG-PLGA), yielding GSE-loaded nanoparticles (NPs) with an average of 230 nm particle size and −35 mV zeta potential, 50% encapsulation efficiency, and sustained release over 96 h. GSE NPs exhibited high colloidal stability in terms of size and high chemical stability in terms of TPC and antioxidant activity for both Marselan and Obeidi when stored at 4 °C for 3 months. GSE NPs showed excellent biocompatibility in human dermal fibroblasts. Both NPs and crude extracts significantly suppressed the proliferation of B16–F10 melanoma cells, particularly Obeidi NPs. This study emphasizes the important role nanotechnology can play in the valorization of bioactive nutraceuticals by presenting GSE NPs as a promising nanoformulation against skin cancer.

A recoverable hydrophilic deep eutectic solvent for efficient extraction of polyphenolic compounds from raspberry root.

Green deep eutectic solvents (DESs) are widely used to extract bioactive components from plant biomass; however, hydrophilic DES and bioactive component isolation methods have not been developed. In this study, we synthesized hydrophilic DES (CL-CA-DES) using citric acid and choline chloride. We combined this with environmentally friendly anion- and cation-exchange resin column chromatographic isolation methods. This approach extracted and isolated four polyphenolic compounds (catechins, epicatechins, procyanidin B1, and procyanidin B2) from raspberry root and efficiently recovered the hydrophilic DES. CL-CA-DES extracted significantly higher contents of catechin and procyanidin B2 from raspberry root compared to other solvents. It also extracted substantially higher contents of epicatechin compared to butyl alcohol, 70% ethanol, and water, but there was no significant difference when compared with acetone and ethyl acetate. Additionally, CL-CA-DES extracted significantly higher contents of procyanidin B1 compared to butyl alcohol, water, and ethyl acetate, with no significant difference when compared with 70% ethanol and acetone. The isolation efficiency of the bioactive components in the raspberry root extract by anion- and cation-exchange resin column chromatography was higher than that of the organic solvent extraction and precipitation generation methods, and the method was effective in recovering CL-CA-DES with a recovery rate higher than 60%. In conclusion, this study developed a new method for the efficient recovery of hydrophilic CL-CA-DES, which can be used for isolating polyphenolic compounds from raspberry root.

Study on the Effect of Sooty Mould Disease in Tea Plants.

Sooty mould (SM) disease affects the growth, development and metabolism of plants and reduces the commodity and economic value of crops. SM disease is one of the important leaf diseases in tea plants. Nonetheless, studies on the effect of SM disease in tea plants are rare. Herein, we found that SM disease disrupted the cell morphology and structure and reduced the contents of caffeine, theanine, and catechins in the mature leaves of tea plants. Transcriptome analysis revealed that SM disease inhibited the biosynthesis of lignin, chlorophyll, catechin, caffeine, and theanine and affected the plant-pathogen interactions in the mature leaves of tea plants by downregulating gene expression. In addition, two fungal isolates, MTzyqA and MTzyqB, were obtained from the mature leaves of diseased tea plants. These strains were identified as Cladosporium pseudocladosporioides by mulitgene phylogenetic analysis, and they grew epiphytically on the leaves of tea plants. The biocontrol bacteria JT68, ZGT5, and BX1 had obvious inhibitory effect on MTzyqA and MTzyqB. These results provide a basis for understanding the effect of SM disease in tea plants.

ABA and MeJA Induced Catechin and Epicatechin Biosynthesis and Accumulation in Camellia oleifera Fruit Shells.

Camellia oleifera Abel, one of the most valuable woody oil plants, has been widely cultivated for extracting edible oil. The shell of C. oleifera is a by-product generated in the processing of edible oil extraction. However, there is still limited research on the maturity and high-value resource utilization of shell by-products. We found that the C. oleifera 'Huashuo' (HS) fruit shells contained a high content of catechins. Abscisic acid (ABA) and methyl jasmonate (MeJA) enhanced the accumulation of catechins in C. oleifera fruit shells, providing a basis for production and application of the catechins in fruit shells of C. oleifera. We further found that 500 μM ABA and 900 μM MeJA significantly promoted the accumulation of catechin (C) and epicatechin (EC) in fruit shells. Following treatment with 900 μM MeJA, the expressions of CoPAL1, CoC4H1, CoC4H2, CoC4H3, Co4CL1, Co4CL2, CoF3'H1, CoLAR1, CoLAR2, CoLAR3, CoANR2, and CoANRL2 were significantly upregulated, while after 500 μM ABA treatment the expressions of CoPAL3, CoCHS1, CoCHS4, CoF3'H1, CoDFR, CoLAR1, CoLAR2, CoLAR3, CoANS1, CoANR1, and CoANR2 increased dramatically. These results indicate that appropriate concentrations of ABA and MeJA activate C and EC biosynthesis and promote their accumulation in fruit shells. Our results provide new ideas and guidance for promoting the resource utilization of C. oleifera fruit shells.

Основные группы биологически активных веществ в растениях видов Hemerocallis L.

Abstract. Wild species of the genus Hemerocallis L. – family Hemerocallidaceae Br. – are of value as ornamental, food and medicinal plants. Biologically active substances of the species composition of lilies growing in natural habitats have not been studied enough. There is no information on the quantitative content of the main groups of biologically active substances in the five types of lilac cultivated in the forest-steppe zone of the Novosibirsk region over the two growing seasons, which determines the originality and significance of this work. The purpose of the study is a comparative study of the content of the main groups of biologically active substances (BAS) in plants of five species of lilac cultivated in the forest-steppe zone of Western Siberia. Methods. A spectrophotometric method was used to determine flavonols, catechins, carotenoids; carbazole-free – for the determination of pectins and protopectins; titrimetric – for the determination of tannins. Results. Comparative analysis of BAV in flowers and leaves of five species of lilac allowed to establish that in leaves the content of catechins (1.1–1.3 times), flavonols (2.0 times), tannins (1.6–2.3 times) is higher than in flowers. The content of pectins is higher in flowers (1.7–3.3 times), protopectins (1.4 times), carotenoids (3.7–34.4 times). The concentration of protopectins in leaves and flowers of all species is 1,4–5.1 times higher compared to pectins. H. minor (flavonols, pectins), H. middendorffii (tannins, catechins, carotenoids), H. citrina (catechins), H. fulva (tannins), H. lilio-asphodelus (pectins) were distinguished by high indications for individual components in various organs. Species specificity of accumulation of these components in flowers and leaves during the period of mass flowering and specificity of their content over two growing periods has been established. Scientific novelty. For the first time in the conditions of the forest-steppe zone of the Novosibirsk region, a comparative quantitative analysis of the content of phenolic compounds, pectin substances, carotenoids in the aboveground organs of H. lilio-asphodelus, H. minor, H. middendorffii, H. citrina, H. fulva during the growing season of 2019–2020 was carried out.