Relationship between tea pigments and health: A bibliometric and visual analysis

Tea pigments have significant effects on human health.However,more attention have been paid to their physiological functions.The aim of this study was to analyze the quantitative and qualitative impact of tea pigments on human health,together with their current and potential future research directions.The study searched and screened 520 publications on WOS from January 2002 to December 2022.The article collected and collated literature published in the last 20 years and analyzed it bibliometrically for years,journals,countries,authors,topics,keywords and strongest citation bursts.The findings of keywords and strongest citation bursts revealed that the most discussed research topics were anticancer,black tea polyphenol,antioxidant,activator inhibitor,in vivo,gut microbiota,and summarize the relevant literature.As a reference for future research,the literature pointed out current shortcomings and speculated future development trend of tea pigments.

Role of foliar spray of plant growth regulators in improving photosynthetic pigments and metabolites in Plantago ovata (Psyllium) under salt stress–A field appraisal

Salinity is one of the major abiotic factors that limit the growth and productivity of plants.Foliar application of plant growth regulators(PGRs)may help plants ameliorate the negative impacts of salinity.Thus,a field experiment was conducted at the Botanical Garden University of Balochistan,Quetta,to explore the potential role of PGRs,i.e.,moringa leaf extract(MLE;10%),proline(PRO;1μM),salicylic acid(SA;250μM),and thiourea(TU;10 mM)in ameliorating the impacts of salinity(120 mM)on Plantago ovata,an important medicinal plant.Salinity hampered plant photosynthetic pigments and metabolites but elevated oxidative parameters.However,foliar application of PGRs enhanced photosynthetic pigments,including Chl b(21.11%),carotenoids(57.87%)except Chl a,activated the defense mechanisms by restoring and enhancing the metabolites,i.e.,soluble sugars(49.68%),soluble phenolics(33.34%),and proline(31.47%),significantly under salinity stress.Furthermore,foliar supplementation of PGRs under salt stress led to a decrease of about 43.02%and 43.27%in hydrogen peroxide and malondialdehyde content,respectively.Thus,PGRs can be recommended for improved photosynthetic efficiency and metabolite content that can help to get better yield under salt stress,with the best and most effective treatments being those of PRO and MLE to predominately ameliorate the harsh impacts of salinity.

Performance of Local Clay-Titanium Dioxide Core-Shell Extender Pigments in Alkyd Paints

The performance of local clay-titanium dioxide core-shell extender pigments in alkyd paints has been studied. The physico-mechanical properties of the prepared alkyd paints were evaluated according to ASTM measurements. The effects of various environmental and corrosive factors on the paints were also studied. The study showed that the alkyd paint samples formulated using the core-shell pigments generally had low specific gravity (1.30 – 1.38), an indication that more of the core-shell pigments can be incorporated into the alkyd paints with considerable cost savings. The dry film thicknesses of the paint samples falls within 0.24 - 0.39 mm, suggesting that the samples will perform well as anticorrosive coatings and their adhesion properties are generally good, showing that they can withstand abrasive and corrosive agents. The core-shell extender pigments formulated paint samples were observed to exhibit the best dust-free, tack-free, and through dry times compared to TiO2 paint formulation. The formulated paint samples generally performed well on exposure to rain and sunlight as well as in distilled water, 2% Na2CO3, and 2% H2SO4 with only TiO2 paint formulation exhibiting rust. The good paint performance characteristics obtainable with the core-shell extender pigments are enough evidence to justify their utilization in the surface coatings industry. The performances of these core-shell extender pigments in alkyd paints have shown that they combine the properties of both the clays and titanium dioxide, and have the potential to overcome their disadvantages.

Selective feeding of bay scallop Argopecten irradians on phytoplankton community revealed by HPLC analysis of phytopigments in Bohai Sea, China

Understanding the feeding selectivity on phytoplankton by shellfi sh is currently a big challenge. In order to investigate the feeding behavior of bay scallop ( Argopecten irradians ) on phytoplankton, we compared its compositions of phytopigments in digestive glands with those in the surrounding seawater, and conducted fi ve consecutive investigations between July and November 2016 in a bay scallop culture area along coast of Qinghuangdao City, northwest of the Bohai Sea, China. Phytopigments in four-size fractionated phytoplankton of seawater (micro-(20-200 μm);nano(L)-[10-20 μm];nano(S)-[2.7-10 μm], and pico-[<2.7 μm]) and digestive glands of A . irradians were examined to investigate the selective feeding of A . irradians . Results show that fucoxanthin and peridinin constituted the major part of taxonomically diagnostic carotenoids (TDCs) in the micro- and nano(L)-phytoplankton in seawater. Compared with total phytoplankton biomass of seawater (TPB, sum of the four sizes), a substantial decrease of fucoxanthin proportion to total DCs in digestive glands was observed while that of peridinin, 19′-butanoyloxyfucoxanthin, alloxanthin and 19′-hexanoyloxy-fucoxanthin showed an obvious increase when those pigments were mainly confi ned to micro-sized phytoplankton (20-200 μm). However, zeaxanthin and prasinoxanthin were mainly confi ned to nano(s)- and pico-phytoplankton, of which the proportions in digestive glands were usually lower in TPB. The contribution of lutein to total DCs in digestive glands (with an average of 7.23%) increased compared with TPB of seawater (with an average of 0.63%) during all fi ve sampling times.

Composition of algal pigments in surface freshen layer after ice melt in the central Arctic

Seasonal meltwater input creates a thin freshen layer in surface seawater under ice, which largely shifts the algae assemblages. Our recent observation of photosynthetic pigments in the high Arctic showed that ice bottom and 5 m of seawater under ice contained relatively high concentration of fucoxanthin, while chlorophyll b and lutein were the major diagnostic pigments in ice-water interface and 0 m of seawater under ice. Additionally, a notable change of dominant phytoplankton occurred in the top 5 m of seawater under ice, from chlorophytes-dominated at surface to diatoms-dominated at 5 m depth, which might attribute to the sharp salinity gradient （salinity from 12.5 to 28.1） in the surface seawater under ice. Our results imply that phytoplankton community in surface layer under ice would become more chlorophytes in the future warming Arctic Ocean.

Industrial TiO2 based nacreous pigments as functional building materials:Photocatalytic removal of NO

In this paper,the photocatalytic activity of industrial titanium dioxide(TiO2)based nacreous pigments was researched as functional building materials for photocatalytic NO remove.Three industrial TiO2 based nacreous pigments were selected to estimate the photocatalytic activity for NO remove.This study is a good proof that pearlescent pigments can eliminate NO,and its performance is positively correlated with its titanium dioxide content.And this research will widen the application of nacreous pigments in functional building materials,and provide a new way to eliminate in door nitric oxide pollution.

Effects of light quality on growth rates and pigments of Chaetoceros gracilis(Bacillariophyceae)

Light is an important parameter in algal culturing.In this work,the effects of different light qualities on growth of the marine diatom Chaetoceros gracilis are evaluated.The cells were cultured under light quantum flux density of 60μmol photons/(m2·s)with nine light qualities:LED red light(LR),LED blue light(LB),LED red plus LED blue light(LR+LB),LED white light(LW),fluorescent white light(FW),and combinations of LW and FW lights with increased proportions of red or blue light(FW+LR,FW+LB,LW+LR,and LW+LB).Blue light promoted the growth of C.gracilis largely.Three light qualities,FW+LR,LW+LR,and LR,resulted in the lowest growth rate.Both chlorophyll and carotenoids reached the highest level under LB and the lowest level under LR among monochromatic light sources;however,increasing of the proportion of blue or red light in the white light induced an increase of the chlorophyll and carotenoid concentrations.Light absorption ability of microalgae was critical for the growth of these organisms,as we observed a positive correlation between the extinction coefficient at different wavelengths and the specific growth rate.These findings are of importance to improve the culturing of this alga in bioreactors.

Effects of Cadmium on Growth, Photosynthetic Pigments, Photosynthetic Performance, Biochemical Parameters and Structure of Chloroplasts in the Agarophyte <i>Gracilaria domingensis</i>(Rhodophyta, Gracilariales)

This paper aimed to evaluate the effects of different concentrations of cadmium on growth rates, photosynthetic pigments, photosynthetic performance, biochemical parameters and structure of chloroplasts in G. domingensis. To accomplish this, apical segments of G. domingensis were cultivated with different concentrations of cadmium, ranging from 100 to 300 μM, over a period of 16 days, and were processed for transmission electron microscopy analysis. The plants exposed to cadmium showed chloroplast alteration, especially degeneration of thylakoids and a decrease in the concentration of photosynthetic pigments, such as chlorophyll a and phycobiliproteins. However, the volume of plastoglobuli increased. As a defense mechanism, the plants treated with cadmium showed an increase in glutathione reductase activity. These results agree with the decreased photosynthetic performance and relative electron transport rate observed after exposure of algae to cadmium. Taken together, these findings strongly indicate that cadmium negatively affects the ultrastructure and metabolism of the agarophyte G. domingensis, thus posing a threat to the economic vitality of this red macroalga.

Optimization and design of pigments for heat-insulating coatings

This paper reports that heat insulating property of infrared reflective coatings is obtained through the use of pigments which diffuse near-infrared thermal radiation. Suitable structure and size distribution of pigments would attain maximum diffuse infrared radiation and reduce the pigment volume concentration required. The optimum structure and size range of pigments for reflective infrared coatings are studied by using Kubelka-Munk theory, Mie model and independent scattering approximation. Taking titania particle as the pigment embedded in an inorganic coating, the computational results show that core-shell particles present excellent scattering ability, more so than solid and hollow spherical particles. The optimum radius range of core-shell particles is around 0.3 - 1.6 μm. ~rthermore, the influence of shell thickness on optical parameters of the coating is also obvious and the optimal thickness of shell is 100-300 nm.

Identification of quantitative trait loci and candidate genes controlling seed pigments of rapeseed

Rapeseed(Brassica napus L.)is an important source of edible vegetable oil and feed protein;however,seed pigments affect the quality of rapeseed oil and the feed value of the residue from oil pressing.Here,we used a population of rapeseed recombinant inbred lines(RILs)derived from the black-seeded male parent cultivar Zhongyou 821 and the yellow-seeded female parent line GH06 to map candidate genes controlling seed pigments in embryos and the seed coat.We detected 94 quantitative trait loci(QTLs)for seed pigments(44 for embryos and 50 for seed coat),distributed over 15 of the 19 rapeseed chromosomes.These included 28 QTLs for anthocyanidin content,explaining 2.41–44.66% of phenotypic variation;24 QTLs for flavonoid content,explaining 2.41–20.26% of phenotypic variation;16 QTLs for total phenol content,accounting for 2.74–23.68% of phenotypic variation;and 26 QTLs for melanin content,accounting for 2.37–24.82% of phenotypic variation,indicating that these traits are under multigenic control.Consensus regions on chromosomes A06,A09 and C08 were associated with multiple seed pigment traits,including 15,19 and 10 QTLs,respectively,most of which were major QTLs explaining>10% of the phenotypic variation.Based on the annotation of the B.napus"Darmor-bzh"reference genome,67 candidate genes were predicted from these consensus QTLs regions,and 12 candidate genes were identified as potentially involved in pigment accumulation by RNA-seq and qRT-PCR analysis.These preliminary results provide insight into the genetic architecture of pigment biosynthesis and lay a foundation for exploring the molecular mechanisms underlying seed coat color in B.napus.

Estimating Hansen solubility parameters of organic pigments by group contribution methods

The Hansen solubility parameters(HSP)are frequently used for solvent selection and characterization of polymers,and are directly related to the suspension behavior of pigments in solvent mixtures.The performance of currently available group contribution(GC)methods for HSP were evaluated and found to be insufficient for computer-aided product design(CAPD)of paints and coatings.A revised and,for this purpose,improved GC method is presented for estimating HSP of organic compounds,intended for organic pigments.Due to the significant limitations of GC methods,an uncertainty analysis and parameter confidence intervals are provided in order to better quantify the estimation accuracy of the proposed approach.Compared to other applicable GC methods,the prediction error is reduced significantly with average absolute errors of 0.45 MPa^(1/2),1.35 MPa^(1/2),and 1.09 MPa^(1/2) for the partial dispersion(δD),polar(δP)and hydrogen-bonding(δH)solubility parameters respectively for a database of 1106 compounds.The performance for organic pigments is comparable to the overall method performance,with higher average errors forδD and lower average errors forδP andδH.

Determination of Six Synthetic Pigments inCompound Wine by HPLC

The aim of this work was to establish a method that the 6 synthetic pigments in compound wine were determined by HPLC.The synthetic pigments in the compound wines were extracted by liquid-liquid extraction, separated by C_(18) symmetry chromatographic column, with 0.02 mol/L ammonium acetate and methanol as the mobile phase with gradient elution, the sample was detected by diode array detector.The test results showed that the artificial synthetic pigment in 0.20-20 μg/L range of concentration had a good linear relationship(r>0.999 2), the detection limits were 0.000 16-0.001 04 g/kg, the recovery rates were 82.0%-97.0%, the relative standard deviation were 0.7%-3.5%. The method was simple, rapid, high sensitivity, good separation effect and can be widely used in the daily inspection work.

Separation and Purification of Monascus Pigments from Red Yeast Rice

It is difficult to extract beneficial components from Monascus pigments due to their complex composition. The low purity of Monascus pigment preparations limits their further application in research and production. Therefore, this study was conducted to optimize the conditions for extraction and isolation of Monascus pigments from red yeast rice, to improve the purity of Monascus pigment preparations. Three fractions were isolated using column chromatography from red yeast rice, they were red, orange and yellow respectively. Then, the three fractions were analyzed for composition and purity using thin layer chromatography and liquid chromatography-mass spectrometry(LC-MS). The chromatograms revealed that the yellow and orange fractions had complex compositions that were difficult to be separated, while the red fraction consisted of fewer components. Finally, a single component was isolated from the red fraction using a thin layer chromatography plate, identified as monascorubramine according to its molecular mass.

FREE RADICAL INTERMEDIATES THEIR POLARIZATION DURING REDOX PROCESSES OF BILE PIGMENTS

The investigation of bile pigments (bilirubin (BR), biliverdin (BV), purpurin (Pu), choletelin (Ch) etc.) by cyclic voltammetry, in-situ rapid scanning thin layer spectroelectrochemistry and ESR spectroscopy indicates that many free radical intermediates and polymers are produced during oxidation and reduction processes.

Seasonal Composition of Lipids, Fatty Acids Pigments in the Brown Alga Sargassum pallidum: The Potential for Health

The present study describes the content of total lipids (TL), the main components of polar and neutral lipids (NL) and photosynthetic pigments (PSP) in edible seaweed Sargassum pallidum (Ochrophyta) from the Sea of Japan, Russia, in different months of the year, taking into account life cycle. Special attention was paid to the fatty acids (FAs) of total lipids as well as the accumulation of important polyunsaturated fatty acids (PUFAs) in glyceroglycolipids (GL) and reserve lipids in the seasonal cycles of growth. The content of TL strongly varied in the course of a year. The major lipid components were GL (20.3% - 36.4%) and NL (19.8% - 30.6%), while phospholipids (PL) were present in negligible amounts (3.2% - 6.9%). Significant seasonal variations were observed in content all classes of lipids. The PUFAs prevailed in total lipids and the content of n-6 PUFAs was higher than n-3 PUFAs on all stages of life with the exception of vegetation period. Monogalactosyldiacylglycerols (MGDG) and digalactosyldiacylglecerols (DGDG) were rich in PUFAs and n-3 PUFAs were dominated among them independently of stages of growth. Saturated fatty acids (SFA) were dominated in sulfoquinovosyldiacylglycerols (SQDG). Triacylglycerols (TAG) and diacylglycerols (DAG) contained many PUFAs, especially n-6 PUFAs. Significant concentration 20:3 n-6 was in the triacylglycerols. The concentration of chlorophylls and carotenoids was increased with the growth and maturation of S. pallidum and reached maximum in period of highest day length and water temperature. The content of pigments decreased with the onset of short days and decreasing water temperatures. Nutritional value and benefit for health of human this alga were evaluated. The n-6/n-3 PUFAs ratio, nutritional quality index (atherogenic and thrombogenic indices, and ratio between hypocholesterolemic and hypercholesterolemic fatty acids) were low, suggesting a high nutritional value of S. pallidum throughout the year.

Changes of pigments and lipids composition in Haematococcus pluvialis vegetative cell as affected by monochromatic red light compared with white light

Much attention has been paid on studies of astaxanthin accumulation process in H aematococcus pluvialis industry. However, growth of H. pluvialis in motile vegetative stage is still the most important and problematic part in the whole cultivation process, such as low growth rate and cell yields. Motile vegetative cells are extremely sensitive to various stresses which make it difficult to maintain the cells of this state to grow. Previous reports showed that motile vegetative cells may have higher biomass yields ifapplied monochromatic red light. However, metabolic responses of these cells are not completely understood, which constraints application of this illumination protocol in industry. The aim of this study was to examine how critical biochemical changes of H. pluvialis motile vegetative cells were af fected by red light when compared with white light. Variation of photosynthetic pigments composition and lipids were mainly studied. By comparing growth process of cultures in red light and white light, prominent variation of pigments composition and lipids changes were observed. The results showed that, even though cell proliferation was the same during exponential growth phase, variation of photosynthetic pigment composition and lipids occurred. The final biomass of cell number was higher in red light group than in white light group. The variations were significant different. Increase or decrease of major photosynthetic membrane lipids to some extent did not influence photosynthesis of the vegetative cells during this phase. However, vegetative cells under polychromatic white light other than monochromatic red light need further metabolic process to adjust its pigment composition and lipids, possibly this is energetically and biochemically unfavorable for motile vegetative cells to growth under white light, a light condition normally not considered as a stress.

A study of chlorophyll-like and phycobilin pigments in the C endosymbiont of the apple- snail Pomacea canaliculata

Pigments present in the brown-greenish C morph of an intracellular endosymbiont of Pomacea canaliculata were investigated.Acetone extracts of the endosymbiotic corpuscles showed an absorption spectrum similar to that of chlorophylls.Three fractions obtained from silica gel column chromatography of the acetone extracts(CI,CII and CIII),were studied by positive ion fast atom bombardment-mass spectrometry(FAB–MS)and hydrogen-nuclear magnetic resonance(H-NMR).Results indicated the presence of(1)a sterol in the yellow colored CI fraction;(2)a mixture of pheophorbides a and b in the major green fraction,CII;and(3)a modified pheophorbide a in the smaller green fraction,CIII.Aqueous extracts of the C endosymbiont did not show evidence of the occurrence of C-phycocyanin,allophycocyanin or phycoerithrin(light absorption,fluorescence emission,and electrophoresis of the protein moieties)while cyanobacterial cells(Nostoc sp.)showed evidence of C-phycocyanin and allophycocyanin.The possible phylogenetic and functional significance of the pigments present in the C endosymbiont is discussed.

Fast identification of mural pigments at Mogao Grottoes using a LIBS-based spectral matching algorithm

To quickly identify the mineral pigments in the Dunhuang murals,a spectral matching algorithm(SMA)based on four methods was combined with laser-induced breakdown spectroscopy(LIBS)for the first time.The optimal range of LIBS spectrum for mineral pigments was determined using the similarity value between two different types of samples of the same pigment.A mineral pigment LIBS database was established by comparing the spectral similarities of tablets and simulated samples,and this database was successfully used to identify unknown pigments on tablet,simulated,and real mural debris samples.The results show that the SMA method coupled with the LIBS technique has great potential for identifying mineral pigments.

Photosynthetic pigments accumulation and some growth indices of cowpea, maize and tomato in response to interspecific and intraspecific competition stress

This study aimed at investigating the photosynthetic pigment accumulation and some growth indices of cowpea, maize and tomato in response to interspecific and intraspecific competition stress. The study was carried out under a screen-house to minimize extraneous factors such as pests and rodents using a randomized complete block design(RCBD). Seeds of cowpea, maize and tomato were collected from the Department of Crop Production and Protection, Faculty of Agriculture,Obafemi Awolowo University, Ile Ife, Osun state, Nigeria. These seeds were planted at a depth of about 3 mm below the soil. The seeds were sown at the rate of six seeds per pot in the monoculture, while in the pots designed for the mixed culture of maize and cowpea, maize and tomato, cowpea and tomato, three seeds of each plant were sown. Two seeds of each plant were sown in the pots with the three crops. The treatments were then supplied with 500 m L of tap water in the morning and in the evening respectively until the seedlings become fully established. The photosynthetic pigments were determined spectrophotometrically with three replicates. Plant growth indices were determined according to Hunts(1978) using leaf area and dry matter data collected at four and six weeks after planting. Statistical analysis was performed using statistical analytical software SAS version 9.2. The results indicated that photosynthetic pigments accumulation(Chlorophyll a, b and carotenoid) in maize(15.98, 23.92 and 44.72 μM), Chlorophyll b and carotenoid in tomato plants(12.48 and 1,178.7μM) in the sole stands were more than the mixed culture of maize with cowpea and tomato(7.195, 14.74 and 0.00 μM).Also, total Chlorophyll in maize(1,127.8 μM), Chlorophyll a and total Chlorophyll in tomato(3.95 and 1,317.5 μM) in the mixed culture were more than in the sole culture of maize(1,030.9 μM) and tomato plants(-9.40 and 546.3 μM). The different photosynthetic pigments accumulated in cowpea were greatly enhanced in the mixed culture than in the sole culture.All the photosynthetic pigments of maize, cowpea and tomato in all the treatments analysed in this study were significantly different at P>0.05. Plant growth indices such as net assimilation rate, relative growth rate, crop growth rate and tissue water contents of these plants had higher value in the intercropped than the check crop(sole). These plant growth indices were significantly different to one another at P>0.05. This study concluded that competition for shared resources in the mixed culture of tomato, maize and cowpea enhanced growth and accumulation of photosynthetic pigments.

Involvement of anti-oxidative enzymes, photosynthetic pigments and flavonoid metabolism in the adaptation of Reaumuria soongorica to salt stress

Reaumuria soongorica is a short woody shrub widely found in semi-arid areas of China. It can survive severe environ- mental stress including high salinity in its natural habitat. Thus, we investigated the involvement of anti-oxidative enzymes, photosynthetic pigments and flavonoid metabolism in the adaptation of R. soongorica to saline environments. R. soon- gorica was treated with 0, 100, 200 and 400 mM NaC1 solutions for 14 days. Soil salt content increased significantly by watering with high content of NaC1 solution, and no variation between 8 and 14 days during treatment. The levels ofpe- roxidation of lipid membranes （measured by malondialdehyde content） and the activities of three antioxidant enzymes （superoxide dismutase （SOD）, peroxidase （POD） and ascorbate peroxidase （APX）） increased under salt stress. Chlorophyll and carotenoid content decreased with increasing salt content. The ratio of Chl a/Chl b and carotenoid/Chl exhibited sig- nificant increase under 400 mM NaC1. However, total flavonoid and anthocyanin contents and key enzyme activities in the flavonoid pathway including phenylalanine ammonialyase （PAL） and Chalcone isomerase （CHI） decreased under salt stress. These findings possibly suggest that R. soongorica has an adaptation protection mechanism against salt-induced oxidative damage by inducin~ the activity of antioxidant enzymes and maintaining a steady level of carotenoid/Chl.