Polyphenolic antioxidant profiles of yellow camellia

Phytochemical Profiles and Biological Activities of Five Wild Camellia Species from Ta Dung, Vietnam

The C. luuana Orel & Curry (TD3), C. furfuracea (Merr.) Cohen-Stuard (TD4), C. bidoupensis Truong, Luong & Tran (TD6), C. sinensis (L.) Kuntze (TD7), and C. kissii var. spp (TD8), have been traditionally used as a health-promoting beverage by local people in Ta Dung, Dak Nong. Despite their potential health benefits, further scientific data on biological and phytochemical properties of these plants is needed. To address this issue, this study was conducted to investigate phytochemical and biological properties of five Camellia species extracts, using DPPH, ABTS radical scavenging, copper chelating (Cu-chelator), and tyrosinase inhibition (TI), α-amylase (Al-AI), and α-glucosidase (Al-GI) analyses. As results, ten compounds were identified using UPLC method, in which catechins (mainly EGCG and catechin (Cat)), were the most prevalent, and followed by chlorogenic acid (ChlA), quercitrin (Querci), rutin, and quercetin (Querce). Additionally, multiple factor analysis (MFA) also revealed that TD7, TD3, and TD4 containing high TPC, TFC, high concentrations of EGCG, ChlA, and caffeine were responsible for their high DPPH, ABTS radical scavenging activities, as well asTI, Al-AI and Al-GI. Furthemore, TD6 and TD8, possessing elevated levels of Apig, Querci, Rutin, Querce, Cat, and EA, exhibited a high Cu-chelator property, but a weak enzyme inhibition. From all above-mentioned results, the antioxidative and enzyme inhibitory potentials of Camellia species extracts collected in Dak Nong province in Vietnam were scientifically demonstrated paving a pathway to develop health supplement in further studies.

Proteomic analysis identified proteins that are differentially expressed in the flavonoid and carotenoid biosynthetic pathways of Camellia Nitidissima flowers

BACKGROUND

Camellia nitidissima Chi is a popular ornamental plant because of its golden flowers, which contain flavonoids and carotenoids. To understand the regulatory mechanism of golden color formation, the metabolites of C. nitidissima petals at five different developmental stages were detected, a proteome map of petals was first constructed via tandem mass tag (TMT) analysis, and the accuracy of the sequencing data was validated via parallel reaction monitoring (PRM).

RESULTS

Nineteen color components were detected, and most of these components were carotenoids that gradually accumulated, while some metabolites were flavonoids that were gradually depleted. A total of 97,647 spectra were obtained, and 6,789 quantifiable proteins were identified. Then, 1,319 differentially expressed proteins (DEPs) were found, 55 of which belong to the flavonoid and carotenoid pathways, as revealed by pairwise comparisons of protein expression levels across the five developmental stages. Notably, most DEPs involved in the synthesis of flavonoids, such as phenylalanine ammonium lyase and 4-coumarate-CoA ligase, were downregulated during petal development, whereas DEPs involved in carotenoid synthesis, such as phytoene synthase, 1-deoxy-D-xylulose-5-phosphate synthase, and β-cyclase, tended to be upregulated. Furthermore, protein‒protein interaction (PPI) network analysis revealed that these 55 DEPs formed two distinct PPI networks closely tied to the flavonoid and carotenoid synthesis pathways. Phytoene synthase and chalcone synthase exhibited extensive interactions with numerous other proteins and displayed high connectivity within the PPI networks, suggesting their pivotal biological functions in flavonoid and carotenoid biosynthesis.

CONCLUSION

Proteomic data on the flavonoid and carotenoid biosynthesis pathways were obtained, and the regulatory roles of the DEPs were analyzed, which provided a theoretical basis for further understanding the golden color formation mechanism of C. nitidissima.

A Comprehensive Strategy for Metabolites Profiling of Flowers and Leaves from Camellia tienii, an Endemic Golden Tea of Vietnam

Golden camellia is defined as a species of the Camellia genus with yellow flowers, which have long been used as a medicine, food, and cosmetic in many Asian countries. To date, more than 50 golden camellia species are considered endemic in Vietnam; however, more information is needed about its chemical constituents and biological activity. This work aims to unveil the potential of Camellia tienii Ninh, a golden camellia species, as an herbal beverage by examining the presence and abundance of chemical components in flowers and leaves. A comprehensive strategy has been developed using both liquid and gas chromatography coupled with mass spectrometry. Specifically, LC-MS-based widely targeted analyses were opted to characterize 158 polar metabolites belonging mainly to flavonoids, catechins, and amino acids classes, and an untargeted approach using GC-MS annotated 42 major volatile compounds such as terpenes and fatty acids. The extensive profile revealed by these techniques could help understand the significant discrimination between two organs. C. tienii flowers accumulated more flavonoids, amino acids, and fatty acids, while leaves contain more terpenes, suggesting different pharmacological properties of these materials. Overall, this pipeline can be applied for other Camellia species and valorization of these valuable resources for health benefits purposes.

A Systematic Methodology for the Identification of the Chemical Composition of the Mongolian Drug Erdun-Uril Compound Utilizing UHPLC-Q-Exactive Orbitrap Mass Spectrometry

The traditional Mongolian medicine Erdun-Uril is a conventional combination of 29 herbs commonly used for the treatment of cerebrovascular ailments. It has the effects of reducing inflammation, counteracting oxidative stress, and averting strokes caused by persistent cerebral hypoperfusion. Prior research on Erdun-Uril has predominantly concentrated on its pharmacodynamics and mechanism of action; however, there has been a lack of systematic and comprehensive investigation into its chemical constituents. Therefore, it is crucial to establish an efficient and rapid method for evaluating the chemical constituents of Erdun-Uril. In this study, Erdun-Uril was investigated using UHPLC-Q-Exactive Orbitrap MS combined with parallel reaction monitoring for the first time. Eventually, a total of 237 compounds, including 76 flavonoids, 68 phenolic compounds, 19 alkaloids, 7 amino acids, etc., were identified based on the chromatographic retention time, bibliography data, MS/MS2 information, neutral loss fragments (NLFs), and diagnostic fragment ions (DFIs). And of these, 225 were reported for the first time in this study. This new discovery of these complex components would provide a reliable theoretical basis for the development of pharmacodynamics and quality standards of the Mongolian medicine Erdun-Uril.

Bioactivity-Guided Isolation of Secondary Metabolites with Antioxidant and Antimicrobial Activities from Camellia fascicularis

Camellia fascicularis has important ornamental, medicinal, and food values, which also have tremendous potential for exploiting bioactivities. We performed the bioactivity-guided (antioxidant and antimicrobial) screening of eight fractions obtained from the ethyl acetate phase of C. fascicularis. The antioxidant activity was measured by DPPH, ABTS, and FRAP, and the antibacterial activity was measured by the minimum inhibitory concentration (MIC) of Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus. The results of bioactivity-guided isolation indicated that the major antioxidant compounds in the ethanolic extracts of C. fascicularis may be present in fractions (Fr.) (A-G, obtained after silica gel column chromatography). Fr. (D-I, obtained after silica gel column chromatography) is a fraction of C. fascicularis with antimicrobial activity. The structures of compounds were determined by spectral analysis and nuclear magnetic resonance (NMR) combined with the available literature on secondary metabolites of C. fascicularis leaves. In this study, 17 compounds were identified, including four phenolics (1, 3-4, and 14), a phenylpropane (2), five terpenoids (5-7, 12, and 15), four flavonoids and flavonoid glycosides (8-10 and 16), and two lignins (13 and 17). Compounds 4-7, 13-15, and 17 were isolated from the genus Camellia for first time. The remaining compounds were also isolated from C. fascicularis for first time. The evaluation of antioxidant and antimicrobial activities revealed that compounds 1, 3, 9, 11, and 17 exhibited higher antioxidant activity than the positive control drug (ascorbic acid), and compounds 4, 8, 10, and 13 showed similar activity to ascorbic acid. The other compounds had weaker or no significant antioxidant activities. The MIC of antibacterial activity for compounds 4, 7, and 11-13 against P. aeruginosa was comparable to that of the positive control drug tetracycline at 125 µg/mL, and other secondary metabolites inhibited E. coli and S. aureus at 250-500 µg/mL. This is also the first report of antioxidant and antimicrobial activities of compounds 5-7, 13-15, and 17. The results of the study enriched the variety of secondary metabolites of C. fascicularis and laid the foundation for further research on the pharmacological efficacy and biological activity of this plant.

Secondary Metabolites with Antioxidant and Antimicrobial Activities from Camellia fascicularis

Camellia fascicularis has important ornamental, medicinal, and food value. It also has tremendous potential for exploiting bioactivities. However, the bioactivities of secondary metabolites in C. fascicularis have not been reported. The structures of compounds were determined by spectral analysis and nuclear magnetic resonance (NMR) combined with the available literature on secondary metabolites of C. fascicularis leaves. In this study, 15 compounds were identified, including 5 flavonoids (1-5), a galactosylglycerol derivative (6), a terpenoid (7), 4 lignans (8-11), and 4 phenolic acids (12-15). Compounds 6-7 and 9-12 were isolated from the genus Camellia for the first time. The remaining compounds were also isolated from C. fascicularis for the first time. Evaluation of antioxidant and antimicrobial activities revealed that compounds 5 and 8-11 exhibited stronger antioxidant activity than the positive drug ascorbic acid, while compounds 7, 13, and 15 showed similar activity to ascorbic acid. The minimum inhibitory concentration (MIC) of antibacterial activity for compounds 5, 7, 9, 11, and 13 against Pseudomonas aeruginosa was comparable to that of the positive control drug tetracycline at a concentration of 62.50 µg/mL; other secondary metabolites inhibited Escherichia coli and Staphylococcus aureus at concentrations ranging from 125-250 µg/mL.

Influence of soil amendments on phytostabilization, localization and distribution of zinc and cadmium by marigold varieties

Marigolds (Tagetes erecta L.) were evaluated for phytoremediation potential of cadmium (Cd) and zinc (Zn) as a function of amendment application to soil. Vermicompost (V), biodigestate (Bi), and combined V + Bi (VBi) were used as soil amendments in Zn and Cd co-contaminated soils. Application of soil amendments can alter physicochemical properties of soils, particularly pH, EC, CEC and nutrient concentrations. The VBi treatment resulted in highest percentage growth rate in biomass (52 %) for the Twenty yellow variety of marigold. Also, in the VBi treatment, leaves of Dragon yellow variety exhibited maximal accumulation of Zn and Cd. Flower extracts of Twenty yellow in the V treatment had substantial carotenoid content (71.7 mg L-1) and lowest IC50 value (43.7 mg L-1), thus indicating it had highest DPPH free radical scavenging activity. Dragon yellow exhibited highest values of ferric reducing antioxidant power (FRAP; 2066 mg L-1), total flavonoids content (TFC; 64.1 mg L-1), and total phenolics content (TPC; 50.9 mg L-1). Using X-ray fluorescence (XRF) spectroscopy, the atomic percentages of Zn and Cd in all marigold varieties and treatments showed similar patterns over flower surfaces, seeds, and flower petals in descending order. Prime yellow in the V treatment resulted in higher Zn accumulation in roots (bioconcentration factor of root value) > 1 and translocation factor value < 1, indicating an enhanced ability of the plant for phytostabilization. Application of V altered antioxidant activities and production of bioactive compounds as well as enhanced the excluder potential of Cd and Zn, particularly in the Prime yellow variety. Application of Bi contributed to increased flower numbers, suggesting that floriculturists cultivating marigolds for ornamental purposes may be able to generate revenue in terms of productivity and quality of flowers when marigolds are grown on contaminated land.

Triterpenes and Pheophorbides from Camellia ptilosperma and Their Cytotoxicity, Photocytotoxicity, and Photodynamic Antibacterial Activity

Phytochemical investigation of the leaves of Camellia ptilosperma S. Y. Liang et Q. D. Chen led to the isolation of ten undescribed compounds, including six new triterpenes (1-6) and four new pheophorbide-related compounds (7-10). Meanwhile, the cytotoxic activity of the six triterpenes against six cancer cell lines was evaluated by MTT assay. Compound 2 showed potent cytotoxicity toward HepG2 cells with an IC50 value of 2.57 μM. Compounds 4 and 5 exhibited cytotoxicity against MDA-MB231 cells, with IC50 values of 11.31 and 5.52 μM, respectively. Additionally, the cytotoxicity of four new pheophorbides against these cancer cells was evaluated both in the presence and absence of light treatment. Compound 7 exhibited exceptional photocytotoxicity against Hela, MCF-7, and A549 cells, with IC50 values of 0.43 μM, 0.28 μM, and 0.92 μM, respectively. Compound 10 demonstrated significant photodynamic cytotoxic activity against BEL-7402 and HepG2 cells with IC50 values of 0.77 μM and 0.33 μM, respectively. The photodynamic antibacterial activity of 7-10 was also tested for S. aureus, E. coli, K. pneumoniae, and P. aeruginosa under direct illumination. Compounds 8 and 10 exhibited sensitivity to E. coli and demonstrated a photodynamic antibacterial effect, with a MIC value of 0.625 μM.

Genotypic and Phenotypic Diversity of Endemic Golden Camellias Collected from the North of Vietnam

Golden Camellias have recently been used as a food, cosmetic, and traditional medicine in China and Vietnam. Forty-two species have natural distribution in Vietnam, of which thirty-two species were considered endemic species of this country. The morphology of leaves and flowers of these species were similar; therefore, their taxonomic identification usually needed experts and the authentication has often been confused among species. Our study aims to describe the genetic diversity and the relationship of six species Camellia phanii, Camellia tamdaoensis, Camellia tienii, Camellia flava, Camellia petelotii and Camellia euphlebia by using three chloroplast DNA-barcodes: matK, rbcL and trnH-psbA. We also clarified the significant differences in anatomical characteristics of midvein and blade of their leaves, which suggested the possibility to use these criteria in taxonomy. In addition, preliminary chemical profiles of the methanolic extracts of leaves from six Golden Camellias such as total phenolic content (TPC), total flavonoid content (TFC), total anthocyanin content (TAC) and chlorogenic acids content (TCGAs) also showed the diversity among them. Interestingly, the discrimination on the catechins profile among six species followed the same tendency with the genetic distance on the phylogeny tree suggesting that catechins (i. e., discriminative catechins) can be biomarkers for the chemotaxonomy of these six Golden Camellias.

A comparative study on photosynthetic characteristics and flavonoid metabolism between Camellia petelotii (Merr.) Sealy and Camellia impressinervis Chang &Liang

Camellia petelotii (Merr.) Sealy and Camellia impressinervis Chang & Liang belong to the golden subgroup of Camellia (Theaceae). This subgroup contains the yellow-flowering species of the genus, which have high medicinal and ornamental value and a narrow geographical distribution. These species differ in their tolerance to high light intensity. This study aimed to explore the differences in their light-stress responses and light damage repair processes, and the effect of these networks on secondary metabolite synthesis. Two-year-old plants of both species grown at 300 µmol·m^-2·s^-1 photosynthetically active radiation (PAR) were shifted to 700 µmol·m^-2·s^-1 PAR for 5 days shifting back to 300 µmol·m^-2·s^-1 PAR for recovery for 5 days. Leaf samples were collected at the start of the experiment and 2 days after each shift. Data analysis included measuring photosynthetic indicators, differential transcriptome expression, and quantifying plant hormones, pigments, and flavonoids. Camellia impressinervis showed a weak ability to recover from photodamage that occurred at 700 µmol·m^-2·s^-1 compared with C. petelotii. Photodamage led to decreased photosynthesis, as shown by repressed transcript abundance for photosystem II genes psbA, B, C, O, and Q, photosystem I genes psaB, D, E, H, and N, electron transfer genes petE and F, and ATP synthesis genes ATPF1A and ATPF1B. High-light stress caused more severe damage to C. impressinervis, which showed a stronger response to reactive oxygen species than C. petelotii. In addition, high-light stress promoted the growth and development of high zeatin signalling and increased transcript abundance of adenylate dimethylallyl transferase (IPT) and histidine-containing phosphotransferase (AHP). The identification of transcriptional differences in the regulatory networks that respond to high-light stress and activate recovery of light damage in these two rare species adds to the resources available to conserve them and improve their value through molecular breeding.

Genome Survey and SSR Analysis of Camellia nitidissima Chi (Theaceae)

Camellia nitidissima Chi (CNC), a species of golden Camellia, is well known as "the queen of camellias." It is an ornamental, medicinal, and edible plant grown in China. In this study, we conducted a genome survey sequencing analysis and simple sequence repeat (SSR) identification of CNC using the Illumina sequencing platform. The 21-mer analysis predicted its genome size to be 2,778.82 Mb, with heterozygosity and repetition rates of 1.42% and 65.27%, respectively. The CNC genome sequences were assembled into 9,399,197 scaffolds, covering ∼2,910 Mb and an N50 of 869 base pair. Its genomic characteristics were found to be similar to those of Camellia oleifera. In addition, 1,940,616 SSRs were identified from the genome data, including mono-(61.85%), di-(28.71%), tri-(6.51%), tetra-(1.85%), penta-(0.57%), and hexanucleotide motifs (0.51%). We believe these data will provide a useful foundation for the development of novel molecular markers for CNC as well as for further whole-genome sequencing of CNC.

Full-Length Transcriptome Sequencing Provides Insights into Flavonoid Biosynthesis in Camellia nitidissima Petals

Flavonoids are the main medicinal ingredients in Camellia nitidissima, but the regulatory mechanism of flavonoid biosynthesis in flowers is unclear; therefore, the flavonoids in C. nitidissima have not been effectively used. The present study performed full-length transcriptome sequencing of C. nitidissima flower. Furthermore, the reported RNA-sequencing data of C. nitidissima petals were reanalyzed using the full-length transcriptome as a reference, and the regulatory mechanism of flavonoid synthesis in petals was elucidated. The analysis identified 43,350 isoforms annotated in non-redundant protein (Nr), Kyoto Encyclopedia of Genes and Genomes (KEGG), EuKaryotic Orthologous Groups (KOG), and Swiss-Prot databases, among which 34,602 aligned to Camellia sinensis genes. A total of 11,857 differentially expressed genes (DEGs), including 112 related to flavonoid synthesis, were identified by pairwise comparison. Subsequently, analysis of the phylogeny and the conserved motifs of R2R3-MYB using the proteins sequences identified three R2R3-MYB transcription factors that regulated flavonoid biosynthesis. Weighted gene co-expression network analysis (WGCNA) identified phenylalanine ammonia-lyase (PAL) and 4-coumarate: CoA ligase(4CL) as the hub genes and showed that bHLH79 interacted with PAL. Finally, validated the expression of seven DEGs involved in flavonoid biosynthesis using real-time quantitative PCR (qRT-PCR). Thus, the present study generated and used the full-length transcriptome as the reference to analyze the transcriptome of petals and proposed a possible regulatory mechanism of flavonoid synthesis in C. nitidissima. The study's findings unravel the genetic mechanisms underlying flavonoid synthesis and suggest candidate genes for the genetic improvement of C. nitidissima.

Application of FT-IR spectroscopy and chemometric technique for the identification of three different parts of Camellia nitidissima and discrimination of its authenticated product

Camellia nitidissima C.W. Chi is a golden camellia recognized in Chinese herbology and widely used as tea and essential oil in Chinese communities. Due to its diverse pharmacological properties, it can be used to treat various diseases. However, unethical sellers adulterated the flower with other parts of Camellia nitidissima in their product. This study used an integrated tri-step infrared spectroscopy method and a chemometric approach to distinguish C. nitidissima’s flowers, leaves, and seeds. The three different parts of C. nitidissima were well distinguished using Fourier transform infrared spectroscopy (FT-IR), second-derivative infrared (SD-IR) spectra, and two-dimensional correlation infrared (2D-IR) spectra. The FT-IR and SD-IR spectra of the samples were subjected to principal component analysis (PCA), PCA-class, and orthogonal partial least square discriminant analysis (OPLS-DA) for classification and discrimination studies. The three parts of C. nitidissima were well separated and discriminated by PCA and OPLS-DA. The PCA-class model’s sensitivity, accuracy, and specificity were all >94%, indicating that PCA-class is the good model. In addition, the RMSEE, RMSEP, and RMSECV values for the OPLS-DA model were low, and the model’s sensitivity, accuracy, and specificity were all 100%, showing that it is the excellent one. In addition, PCA-class and OPLS-DA obtained scores of 27/32 and 26/32, respectively, for detecting adulterated and other TCM reference flower samples from C. nitidissima. Combining an infrared spectroscopic method with a chemometric approach proved that it is possible to differentiate distinct sections of C. nitidissima and discriminate adulterated samples of C.nitidissima flower.

Preparation and Assessment of Some Characteristics of Nanoparticles Based on Sodium Alginate, Chitosan, and Camellia chrysantha Polyphenols

This paper presents the characteristics, morphology, and properties of alginate/chitosan/polyphenol nanoparticles, in which polyphenols were extracted from Camellia chrysantha leaves collected in Tam Dao district, Vinh Phuc province (Vietnam). The alginate/chitosan/polyphenol nanoparticles were prepared by ionic gelation method at different polyphenol content. The characteristics and morphology of these nanoparticles were investigated using infrared spectroscopy (IR), ultraviolet-visible spectroscopy (UV-Vis), and scanning electron microscopy (SEM). Release kinetic of polyphenols from the alginate/chitosan/polyphenol nanoparticles was conducted in simulated human body fluids. The release kinetics of polyphenols from the above nanoparticles were also evaluated and discussed. The experimental results showed that the release process of polyphenols from the nanoparticles was dependent on three factors: time, pH of solution, and amount of polyphenols.

Integrated molecular network and HPLC-UV-FLD analysis to explore antioxidant ingredients in camellia nitidissima Chi

At present, screening of active ingredients from natural products for pharmacological and clinical research is mostly time-consuming and costly. In this study, a molecular network (MN) guided high performance liquid chromatography-ultraviolet-fluorescence detector (HPLC-UV-FLD) method was carried out to profile the global antioxidant activity compounds, including the trace amount ingredients in Camellia nitidissima Chi (CNC). Firstly, HPLC-UV-FLD postcolumn derivatization system was utilized to screen the antioxidants. Then the MN of CNC was established via mass spectrometry (MS) data for getting the connection between ingredient structures. As a result, HPLC-UV-FLD indicated three antioxidant ingredients: gallic acid (126.3 mg/g), catechin (564.8 mg/g), and salicylic acid (24.3 mg/g). Combined with the MN, the actives' precise location and connection relationship were clarified based on the structural similarities. A new antioxidant ingredient, okicamelliaside, was suggested and evaluated at free radical scavenging and enzymatic protection. The novel method of activity and structural correlation analysis based on MN could provide a useful guide for screening trace active ingredients in natural products. PRACTICAL APPLICATION: Three main ingredients were screened out from Camellia nitidissima Chi by HPLC-UV-FLD postcolumn derivatization system. Integrated molecular network and HPLC-UV-FLD analysis, a new type of antioxidant okicamelliaside was selected. The novel method of activity and structural correlation analysis based on molecular network could provide a useful guide for screening trace active ingredients in natural products.

Biochemical Constituents of Phaleria macrocarpa (Leaf) Methanolic Extract Inhibit ROS Production in SH-SY5Y Cells Model

Background. Reactive oxygen species generation in mammalian cells profoundly affects several critical cellular functions, and the lack of efficient cellular detoxification mechanisms which remove these radicals may lead to several human diseases. Several studies show that ROS is incriminated as destructive agents in the context of the nervous system especially with advance in age leading to neurodegeneration. Current treatments of this disease are not effective and result in several side effects. Thus, the search for alternative medicines is in high demand. Therefore, the aim of this study is to evaluate the reactive oxygen inhibitory effect of Phaleria macrocarpa 80% (leaf) extract. Methods. The leaf was extracted with 80% methanol. Cytotoxicity studies were carried out using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), and ROS inhibitory activities were evaluated using dichlorofluorescein diacetate (DCF-DA) assay in the SH-SY5Y cells model. Results. The result revealed ROS inhibitory activities of the crude extract with highly significant differences at $p<0.001$ between the group that were treated with crude extract only, the group treated with crude extract and exposed to H2O2, and the group exposed to H2O2 only as well as the group that were maintained in complete media. Bioactive compounds show the presence of vitexin and isovitexin following the HPLC method. Conclusion. High antioxidant activities and low toxicity effect of this crude revealed its high benefit to be used as natural medicine/supplements.

Antirrhinum majus L. flower extract inhibits cell growth and metastatic properties in human colon and lung cancer cell lines

Snapdragon ( Antirrhinum majus L.) flowers are one of the most frequently used edible flowers in different preparations of foods and drinks. In this study, we examined inhibitory effects of snapdragon flower extract (SFE) against distinctive properties of cancer cells, stimulated growth, and activated metastasis, using H1299 lung cancer and HCT116 colon cancer cell lines. SFE treatment at 100-1,000 μg/ml for 24-72 hr resulted in a time- and dose-dependent growth inhibition in H1299 and HCT116 cells. Cell cycle analysis and Annexin V staining assay further revealed that SFE caused cell cycle arrest at G2/M phase and induction of apoptosis, indicating the growth inhibition by SFE is attributed to its G2/M cell cycle-arresting and apoptosis-inducing activities. SFE dose-dependently enhanced generation of intracellular reactive oxygen species (ROS) and reduced mitochondrial membrane potential in H1299 cells but had no effect on intracellular ROS levels in HCT116 cells, suggesting that the type of apoptosis induced by SFE in H1299 cells is different to that in HCT116 cells. Furthermore, SFE alleviated invasion, levels of matrix metalloproteinases, migration, and adhesion in H1299 and HCT116 cells. These results indicate that SFE not only inhibits cell growth by cell cycle arrest at G2/M and apoptosis induction but also alleviates metastatic properties such as invasion, migration, and adhesion in lung and colon cancer cells.

Neuroprotective effects of Camellia nitidissima Chi leaf extract in hydrogen peroxide-treated human neuroblastoma cells and its molecule mechanisms

Camellia nitidissima Chi (CNC) is a famous medicinal and edible plant with the name of "Tea for Longevity" in Guangxi province of China. In present study, we determined the protective effect of extract from CNC leaves on H2O2-induced cell injury and its underlying mechanisms in human neuroblastoma (SH-SY5Y) cells. The ethyl acetate fraction of CNC leaves (CLE, 50-200 μg/ml) treatment significantly increased the cell viability of H2O2-treated SH-SY5Y cells and reduced the leakage of LDH in a reversed "U"-shape manner. It was confirmed by Hoechst 33,342 staining that CLE attenuated H2O2-induced apoptosis in SH-SY5Y cells. The CLE (100 and 150 μg/ml) treatment significantly relieved H2O2-induced oxidative stress by decreasing intracellular ROS level, and increasing the activities of superoxide dismutase (SOD) and catalase (CAT). Western blot analysis demonstrated that the CLE treatment reserved H2O2-induced decrease of pCREB (Ser133) expression, and its downstream protein BDNF. In addition, 37 phenolic compounds in CLE were identified by UPLC-TOF MS/MS, and the main active phytochemicals seemed to be catechins, quercetin, kaempferol, and their derivatives. In conclusion, the data analysis showed that the neuroprotective effect of CNC leaves might be achieved via synergistically boosting endogenous antioxidant defenses and neurotrophic signaling pathway. These results suggest that CNC leaves are valuable resources for functional foods and beverages.

Comprehensive analysis of the compound profiles of Folium Camelliae Nitidissimae extract by ultrafast liquid chromatography with quadrupole-time-of-flight mass spectrometry and hepatoprotective effect against CCl4 -induced liver injury in mice

Folium Camelliae Nitidissimae (jinhuacha in Chinese, JHC) is a kind of caffeine-less tea with antioxidant, antitumor and antibacterial effects. Studies on the chemical profiles and hepatoprotective effects of JHC extracts have not been systematically conducted so far. This study comprehensively investigated the compound profiles of JHC extract by ultrafast liquid chromatography with quadrupole time-of-flight tandem mass spectrometry. We also determined JHC's hepatoprotective effects against CCl₄ -induced liver injury in mice. A JHC extract was administered orally to mice at 1.95 and 7.80 g/kg body weight once daily for 14 consecutive days prior to CCl₄ treatment. Eighty-four compounds including flavonoids, organic acids, catechins, coumarins, phenylpropanol, amino acids, anthraquinones, saponins and nucleosides in JHC extract were authentically identified or tentatively identified by comparing MS information and retention times with those of authentic standards or available references. JHC administration significantly decreased elevated levels of aspartate aminotransferase and alanine aminotransferase in mouse serum, inhibited hepatic malondialdehyde formation and enhanced glutathione and superoxide dismutase activities in the liver of CCl₄ -treated mice. The histological observations also further supported the results. These results demonstrate that JHC contains various chemical compounds and its hepatoprotective effects against CCl₄ -induced liver injury correlated with decreasing lipid oxidation are significant.

The antioxidant and tyrosinase inhibition properties of essential oil from the peel of Chinese Torreya grandis Fort

The antioxidant and tyrosinase inhibition properties of essential oil from the peel of Chinese Torreya grandis Fort. (CTGF oil) were investigated. The antioxidant properties of CTGF oil were evaluated via 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging tests, and it showed an IC₅₀ value of 0.88 ± 0.06 μg mL^-1 compared to V _C with a value of 1.0 ± 0.1 μg mL^-1 and BHT with a value of 2.9 ± 0.1 μg mL^-1. CTGF oil had relatively significant DPPH scavenging activity (p < 0.05), which could be compared to other natural oils as follows: cassia oil (92.4%) > peppermint oil (89.1%) > clove leaf oil (87.7%) > nutmeg oil (80.1%) > CTGF oil (42.6%) > lemon oil (25.5%). Furthermore, changes in the peroxide values of different treatment groups during storage for 60 days were estimated. CTGF oil displayed better antioxidant activity than lemon oil, with activity similar to that of BHT for the reduction of the peroxide value. Moreover, CTGF oil effectively inhibited the oxidation of 3,4-dihydroxy-l-phenylalanine (l-DOPA) through tyrosinase (P < 0.05). The essential oil obtained after hydrodistillation from the peel of Chinese Torreya grandis Fort. could be potentially utilized as a good new alternative source of natural antioxidants for the food and cosmetics industries.

Essential oils and ethanol extract from Camellia nitidissima and evaluation of their biological activity

Camellia nitidissima, a well-known species of yellow Camellia, has undergone commercial cultivation as a new tea resource recently. Herein, the composition, antioxidant and antimicrobial activities of the essential oil and ethanol extract of C. nitidissima were investigated. The essential oils from the leaves and flowers of C. nitidissima were obtained by hydro-distillation. A total of 56 and 34 constituents accounting for 77.5 and 96.8% of the oils were identified by GC-MS. Linalool (35.8%), phytol (7.9%), cis-geranyl acetone (7.3%) and methyl salicylate (6.8%) were found to be the primary components in the leaf oil, while the flower oil was rich in α-eudesmol (34.3%), γ-eudesmol (31.5%) and linalool (11.1%). The ethanol extract of C. nitidissima leaves contained 281.04 mg gallic acid equivalent/g of total phenols. The antioxidant activities of the two oils and extract were evaluated by DPPH and ABTS radical-scavenging assays. The IC50 values varied from 17.4 (extract) to 720.3 μg/mL (flower oil) for DPPH and from 28.8(extract) to 889.6 μg/mL (flower oil) for ABTS. Both essential oils exhibited moderate antioxidant activities, and the extract possessed strong effects close to ascorbic acid. Additionally, the antimicrobial activities of the oils and extract against Staphylococcus aureus, Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa were evaluated by agar dilution assay. No considerable bactericidal activities were observed for either essential oil or extract compared with ampicillin and tobramycin standards. The results indicated the extract was more efficient than the two essential oils against S. aureus (MIC = 0.625 mg/mL) and B. subtilis (MIC = 1.25 mg/mL).

Comparative genomics analysis reveals gene family expansion and changes of expression patterns associated with natural adaptations of flowering time and secondary metabolism in yellow Camellia

Yellow-flowering species are unique in the genus Camellia not only for their bright yellow pigments but also the health-improving substances in petals. However, little is known regarding the biosynthesis pathways of pigments and secondary metabolites. Here, we performed comparative genomics studies in two yellow-flowered species of the genus Camellia with distinctive flowering periods. We obtained 112,190 and 89,609 unigenes from Camellia nitidissima and Camellia chuongtsoensis, respectively, and identified 9547 gene family clusters shared with various plant species and 3414 single-copy gene families. Global gene expression analysis revealed six comparisons of differentially expressed gene sets in different developmental stages of floral bud. Through the identification of orthologous pairs, conserved and specific differentially expressed genes (DEGs) between species were compared. Functional enrichment analysis suggested that the gibberellin (GA) biosynthesis pathway might be related to the alteration of flowering responses. Furthermore, the expression patterns of secondary metabolism pathway genes were analyzed between yellow- and red-flowered Camellias. We showed that the key enzymes involved in glycosylation of flavonoids displayed differential expression patterns, indicating that the direct glycosylation of flavonols rather than anthocyanins was pivotal to coloration and health-improving metabolites in the yellow Camellia petals. Finally, the gene family analysis of UDP-glycosyltransferases revealed an expansion of group C members in C. nitidissima. Through comparative genomics analysis, we demonstrate that changes of gene expression and gene family members are critical to the variation of natural traits. This work provides valuable insights into the molecular regulation of trait adaptations of floral pigmentation and flowering timing.

The antitumor activity screening of chemical constituents from Camellia nitidissima Chi

Chemotherapy is the preferred and most common treatment for cancer in clinical practice. An increasing number of researchers all over the world are focusing on natural medicines to find new antitumor drugs, and several reports have shown that Camellia nitidissima (C. nitidissima) Chi could reduce blood-lipid, decrease blood pressure, resist oxidation, prevent carcinogenesis and inhibit tumors. Therefore, the pharmacodynamics of the chemical constituents in C. nitidissima need to be investigated further. In the present study, 16 chemical constituents were isolated from the leaves of C. nitidissima, of which 6 compounds are reported to be found in this plant for the first time. Furthermore, all these phytochemicals were screened for antitumor activity on 4 common cancer cell lines, while compound 3, one oleanane-type triterpene, exhibited the most potential antitumor effects. Interestingly, to our knowledge, this was the first report that compound 3 inhibits cancer cells. Compound 3 inhibited EGFR-mutant lung cancer cell line, NCI-H1975 via apoptosis effect, with an IC50 of 13.37±2.05 µM at 48 h. Based on the data, compound 3 showed potential for antitumor drug development, suggesting the scientific basis for the antitumor activity of C. nitidissima.

Antioxidant capacity of phenolics in Camellia nitidissima Chi flowers and their identification by HPLC Triple TOF MS/MS

Camellia nitidissima Chi (CNC) is a valuable medicinal and edible plant in China. In this study, CNC flowers were extracted with 95% ethanol, then partitioned into dichloromethane, ethyl acetate, n-butanol, and water fractions, with the antioxidant capacity of flavonoids and other phytochemicals in CNC flowers investigated for the first time. Results showed that the ethyl acetate fraction exhibited the strongest antioxidant capacity and highest total phenolic content (TPC) compared with the other fractions. Furthermore, in the ethyl acetate fraction, the 50% effective concentrations (EC₅₀) of ABTS⁺ and DPPH radical scavenging activities were 64.24 ± 1.80 and 78.80 ± 0.34 μg/mL, respectively, and the ferric reducing antioxidant power (FRAP) was 801.49 ± 2.30 μM FeSO₄ at 1,000 μg/mL. Pearson’s correlation coefficients and principal component analyses (PCA) for the TPC and antioxidant capacity of the five fractions indicated that the phenolic compounds were the major antioxidant constituents in the flowers. To exploit the antioxidants in CNC flowers, 21 phenolic compounds in the ethanolic extract fraction were identified by HPLC Triple TOF MS/MS, next, 12 flavonoids were isolated and elucidated, of which compounds 1–5 showed potent antioxidant capacity. In addition, the potential structure-activity relationship among these 12 flavonoids showed that (1) the o-catechol group in the B-ring was primarily responsible for the antioxidant capacity of flavonoids and (2) steric hindrance, produced by glycosides and other groups, could reduce the antioxidant capacity of the flavonoids.

Nutritional Compositions and Phytochemical Properties of the Edible Flowers from Selected Zingiberaceae Found in Thailand

The nutritional compositions and phytochemical properties of eight edible flowers of the ginger family (Zingiberaceae) commonly found in Thailand are reported herein. The plant genera investigated were Zingiber (Ginger, Phlai Dam, Krathue), Hedychium (two morphological filament forms), Curcuma (Ao), Etlingera (Torch ginger), Amomum (Chi Kuk), and Alpinia (Galangal), which are eaten fresh or cooked as ingredients in the preparation of many Thai dishes. The proximate compositions (moisture, ash, fiber, protein, fat, and carbohydrate contents) varied among the different genera. The plants sampled were generally low in fat content (<1%), which contributed as little as 30% of the total caloric energy. Edible plant parts contained substantially high amounts of potassium (max. 737.21 mg/100 g), calcium (max. 140.15 mg/100 g), and iron (~0.32 mg/100 g). Among the tested samples, torch ginger had the highest vitamin C content (1.05 mg/100 g), total phenolic and total flavonoid contents, as well as 2,2-diphenyl-1-picrylhydrazyl activity. On the other hand, the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) assay suggested that Hedychium species possessed the highest antioxidant activity (~5.38 mg TEAC/g extract). Our results prove that edible plants of the Zingiberaceae family found in Thailand are rich sources of potentially important nutrients.

The inhibition of advanced glycation end-products by five fractions and three main flavonoids from Camellia nitidissima Chi flowers

Camellia nitidissima Chi (CNC), belonging to Camellia genus (Theaceae family), is a medicinal and edible plant in China. Among the whole plant, the CNC flowers are especially precious, but the biological activities and the compositions of the CNC flowers are unknown. In this study, inhibiting effects on the formation of advanced glycation end-products (AGEs) of five CNC flowers fractions and three isolated compounds were investigated, these three compounds are two flavonoid glycosides and one flavanol, namely kaempferol 3-O-[2,3,4-Tri-O-acetyl-α-L-rhamnopyranosyl-(1→3)-2,4-di-O-acetyl-α-L-rhamnopyranosyl-(1→6)]-β-D-glucopyranoside, kaempferol 3-O-[2,3,4-Tri-O-acetyl-α-L-rhamnopyranosyl-(1→3)-4-O-acetyl-α-L-rhamnopyranosyl-(1→6)]-β-D-glucopyranoside and catechin. Among these five fractions, the ethyl acetate fraction showed the highest total phenolic contents and inhibiting effects on AGE formation. Bovine serum albumin (BSA)-glucose and BSA-methylglyoxal assay showed that the ethyl acetate fraction inhibited AGE formation by 74.49% and 34.3% at 1 mg/mL, respectively. As the main components, these three compounds also showed remarkable inhibiting effects on AGE formation by scavenging methylglyoxal, next two catechin-carbonyl adducts were identified using HPLC-ESI-MS/MS. The results showed that the CNC flowers had remarkable inhibiting effects on the formation of AGEs. The primary structure-activity relationship showed (1) the glycosides could reduce the inhibiting effects compared to kaempferol and (2) the acetyl at position 2‴ in compound 1 had no remarkable influence of the inhibiting effects on AGE formation compared to compound 2.

Hypolipidemic Activity of Camellia euphlebia Flower Extract in High-fat-fed Mice

Camellia euphlebia (family, Theaceae) has been used for the prevention and treatment of cardiovascular diseases in Southern China. However, there has been no report on the hypolipidemic activity of Camellia euphlebia flower. This study evaluated the hypolipidemic activity of different preparation of Camellia euphlebia flower extracts using in vivo models. Mice intragastrically administered aqueous extract at 400 mg/kg dose or ethanol extract at 100 and 400 mg/kg doses of Camellia euphlebia flower for 28 days exhibited significant decreases in the levels of total cholesterol, triglycerides and low-density lipoprotein cholesterol, while displaying increased level of high-density lipoprotein cholesterol in the serum. The Camellia euphlebia flower extracts also improved the antioxidant ability of hyperlipidemic mice as well as protecting the animals against liver damage by lowering the level of glutamic-pyruvic transaminase activity. Furthermore, 400 mg/kg ethanol extract effectively down-regulated the mRNA levels of fatty acid synthase, 3-hydroxy-3-methylglutaryl CoA reductase and glycerol-3-phosphate acyl transferase, suggesting that Camellia euphlebia flower extract may potentially inhibit lipid accumulation in the liver by regulating the expression of fatty acid synthase, 3-hydroxy-3-methylglutaryl CoA reductase and glycerol-3-phosphate acyl transferase. These results provided support for the potential hypolipidemic activity of Camellia euphlebia flower and could partly explain the basis of using Camellia euphlebia for the treatment of hyperlipidemia.

Nuclear Magnetic Resonance-Based Metabolomics Approach to Evaluate the Prevention Effect of Camellia nitidissima Chi on Colitis-Associated Carcinogenesis

Colorectal cancer (CRC) is one of the most common malignant tumors worldwide, occurring in the colon or rectum portion of large intestine. With marked antioxidant, anti-inflammation and anti-tumor activities, Camellia nitidissima Chi has been used as an effective treatment of cancer. The azoxymethane/dextran sodium sulfate (AOM/DSS) induced CRC mice model was established and the prevention effect of C. nitidissima Chi extracts on the evolving of CRC was evaluated by examination of neoplastic lesions, histopathological inspection, serum biochemistry analysis, combined with nuclear magnetic resonance (NMR)-based metabolomics and correlation network analysis. C. nitidissima Chi extracts could significantly inhibit AOM/DSS induced CRC, relieve the colonic pathology of inflammation and ameliorate the serum biochemistry, and could significantly reverse the disturbed metabolic profiling toward the normal state. Moreover, the butanol fraction showed a better efficacy than the water-soluble fraction of C. nitidissima Chi. Further development of C. nitidissima Chi extracts as a potent CRC inhibitor was warranted.

Antioxidative potential, nutritional value and sensory profiles of confectionery fortified with green and yellow tea leaves (Camellia sinensis)

This paper presents a study on development of functional food products containing green and yellow tea leaves. The results indicated that green and yellow tea are significant tools in the creation of the nutritional value, antioxidative potential and stability of the lipid fraction of cookies. Tea-fortified cookies showed considerably higher contents of dietary fiber, especially hemicellulose and insoluble fractions, and were characterized by significantly higher antioxidant potential associated with their phenolics content. Results of ABTS, DPPH, ORACFL and PCL assay showed significantly higher antioxidant potential of tea cookies, highest for yellow tea. The antioxidative potential of applied teas was significant in terms of the inhibition of hydroperoxide content, while formation of secondary lipid oxidation products was less spectacular. It is concluded that tea leaves could be widely used as a source of polyphenols with high antioxidative potential, as well as fiber; thus introducing numerous health benefits for the consumer.

Statistical Approaches to Assess the Association between Phenolic Compounds and the in vitro Antioxidant Activity of Camellia sinensis and Ilex paraguariensis Teas

Tea presents a diverse phenolic composition which is responsible for its alleged biological activities, including the in vivo and in vitro antioxidant capacity. It is very usual to find researches applying statistical methods, such as analysis of variances (ANOVA) and linear Pearson correlation coefficients to analyze the strength of correlation between phenolic composition and the in vitro antioxidant activity of teas from Camellia sinensis (green, black, white, oolong, red, and yellow teas) and Ilex paraguariensis (Yerba-mate), which are the most produced and consumed types of teas. However, evidence has shown that these approaches are not as suitable as multivariate statistical methods once they do not depict nor show association among all results and variables simultaneously, making it difficult to understand clearly the data structure and patterns. Then, the objective of this work is to review and explain some univariate/bivariate and multivariate statistical techniques used to assess the association between phenolic compounds and the in vitro antioxidant activity of green, white, black, red, yellow, oolong and Yerba-mate teas. Moreover, this paper provides an overview on some assays used to estimate the in vitro antioxidant capacity of teas.

Nutritional composition and antioxidant capacity in edible flowers: characterisation of phenolic compounds by HPLC-DAD-ESI/MSn

Edible flowers are commonly used in human nutrition and their consumption has increased in recent years. The aim of this study was to ascertain the nutritional composition and the content and profile of phenolic compounds of three edible flowers, monks cress (Tropaeolum majus), marigold (Tagetes erecta) and paracress (Spilanthes oleracea), and to determine the relationship between the presence of phenolic compounds and the antioxidant capacity. Proximate composition, total dietary fibre (TDF) and minerals were analysed according to official methods: total phenolic compounds (TPC) were determined with Folin-Ciocalteu's reagent, whereas antioxidant capacity was evaluated using Trolox Equivalent Antioxidant Capacity (TEAC) and Oxygen Radical Absorbance Capacity (ORAC) assays. In addition, phenolic compounds were characterised by HPLC-DAD-MSn. In relation to the nutritional value, the edible flowers had a composition similar to that of other plant foods, with a high water and TDF content, low protein content and very low proportion of total fat-showing significant differences among samples. The levels of TPC compounds and the antioxidant capacity were significantly higher in T. erecta, followed by S. oleracea and T. majus. Thirty-nine different phenolic compounds were tentatively identified, with flavonols being the major compounds detected in all samples, followed by anthocyanins and hydroxycynnamic acid derivatives. In T. erecta small proportions of gallotannin and ellagic acid were also identified.

Chemical constituents and anticancer activity of yellow camellias against MDA-MB-231 human breast cancer cells

Yellow camellia, with its golden yellow flowers, is rare in the world. Most studies of yellow camellia have focused on its ornamental properties; however, there are fewer published studies on its medical values. The purpose of this study was to define the chemical constituents and the biological potential of the water extract of leaves in six species of yellow camellia. The data showed that Camellia murauchii had significantly higher total catechins and total polyphenol content than others; Camellia euphlebia had the highest total amino acids and γ-aminobutyric acid. The results indicated that Camellia tunghinensis exhibited the highest free radical scavenging capacity and showed potent anticancer activities. Camellia nitidissima had stronger inhibitory effect than other species on fatty acid synthesis. In addition to catechins, 3-p-coumaroylquinic acid, kaempferol-3-O-glucoside, and quercetin-3-O-glucoside were detected in C. tunghinensis using liquid chromatography-tandem mass spectrometry. Taken together, yellow camellias possess biological activity and are worthy of continued study.

Plant regeneration via somatic embryogenesis and shoot organogenesis from immature cotyledons of Camellia nitidissima Chi

Camellia nitidissima Chi (Theaceae) is a world-famous economic and ornamental plant with golden-yellow flowers. It has been classified as one of the rarest and most endangered plants in China. Our objective was to induce somatic embryogenesis, shoot organogenesis and plant regeneration for C. nitidissima. Three types of callus (whitish, reddish and yellowish) were induced from immature cotyledons on improved woody plant medium (WPM) with different plant growth regulators (PGRs). Among the callus, whitish callus was induced by 4.5 μM 2,4-dichlorophenoxyacetic acid (2,4-D) and reddish and yellowish callus were induced by strongly active cytokinins, thidiazuron (TDZ) or 6-benzylaminopurine (BAP), singly or combined with weakly active auxin, α-naphthaleneacetic acid (NAA). The embryogenic callus could differentiate into somatic embryos, nodular embryogenic structures (large embryo-like structures) or adventitious shoots depending on the PGR used in WPM. BAP was best for adventitious buds and zeatin was best for somatic embryogenesis while kinetin (Kt) was best for the formation of nodular embryogenic structures. The three regeneration pathways often occurred in the same embryogenic callus clumps. Most shoots (80.0%) developed roots in WPM supplemented with 24.6 μM IBA and 0.3 μM NAA while 47.5% of somatic embryos could germinate directly and develop into plantlets on induction medium supplemented with 0.9 μM BAP and 0.1 μM NAA. The nodular embryogenic structures could be sub-cultured and cyclically developed in one of two differentiation pathways: shoot organogenesis or somatic embryogenesis. Plantlets derived from shoot buds rooted and somatic embryos germinated when transplanted into soil in a greenhouse; 66.7% of plantlets from shoot culture and 78.6% of plantlets from somatic embryos survived after 8 weeks' acclimatization.