Higher Levels Of Total Flavonoids Research Articles

Integrated multi-omics investigation revealed the importance of phenylpropanoid metabolism in the defense response of Lilium regale Wilson to Fusarium wilt

Abstract Lilies (genus: Lilium) play a significant role in the global cut-flower industry, but they are highly susceptible to Fusarium wilt caused by Fusarium oxysporum. However, Lilium regale, a wild lily species, exhibits remarkable resistance to F. oxysporum. To investigate the quantitative resistance of L. regale to Fusarium wilt, a comprehensive multi-omics analysis was conducted. Upon inoculation with F. oxysporum, L. regale roots showed a significant accumulation of phenylpropane metabolites, including lignin precursors, flavonoids, and hydroxycinnamic acids. These findings were consistent with the up-regulated expression of phenylpropanoid biosynthesis-related genes encoding various enzymes, as revealed by transcriptomics and proteomics analyses. Furthermore, metabolomics and proteomics data demonstrated differential activation of monoterpenoid and isoquinoline alkaloid biosynthesis. Colorimetry and high-performance liquid chromatography analyses revealed significantly higher levels of total flavonoids, lignin, ferulic acid, phlorizin, and quercetin contents in L. regale scales compared to susceptible lily ‘Siberia’ scales during F. oxysporum infection. These phenylpropanes exhibited inhibitory effects on F. oxysporum growth and suppressed the expression of pathogenicity-related genes. Transcriptional regulatory network analysis suggested that ethylene-responsive transcription factors (ERFs) may positively regulate phenylpropanoid biosynthesis. Therefore, LrERF4 was cloned and transiently overexpressed in the Fusarium wilt-susceptible Oriental hybrid lily, ‘Siberia’. The overexpression of LrERF4 resulted in increased levels of total flavonoids, lignin, ferulic acid, phlorizin, and quercetin, while the silencing of LrERF4 in L. regale through RNAi had opposite effect. In conclusion, phenylpropanoid metabolism plays a crucial role in the defense response of L. regale against Fusarium wilt, with LrERF4 acting as a positive regulator of phenylpropane biosynthesis.

Comparative analysis of the phenolic contents and antioxidant activities of different parts of two pomegranate (Punica granatum L.) Cultivars: 'Tunisia' and 'Qingpi'.

Pomegranate (Punica granatum L.), with its abundant phenolic substances and strong antioxidant activity, holds significant research and utilization potential across various organs. However, there have been few studies on the phenolic content and antioxidant activity of different parts of pomegranate, especially the placenta. This study investigated the phenolic content and antioxidant activity of fruits, flowers, and leaves of two pomegranate varieties, 'Tunisia' and 'Qingpi', throughout their growth and development. Results indicated significant variations in phenolic content among different organs, with petals exhibiting the highest total polyphenol content (TPC, 49.40 mg GAE/g FW) and total anthocyanin content (TMAC, 1938.54 nmol/g FW). Placenta contained the highest levels of total flavonoids (TFC, 173.58 mg RE/g FW) and punicalagin (109.30 mg/g FW). The peel had the highest content of total flavanols (TFAC, 19.42 mg CE/g FW). Over the course of pomegranate development, total polyphenols, total flavonoids, total flavanols, punicalagin, and antioxidant activity declined in different organs. Antioxidant activity followed the order: fruit > flower > leaf, with the placenta exhibiting the highest antioxidant activity among fruits. Antioxidant activity showed a significant positive correlation with total polyphenols (R2=0.77-1.00), total flavonoids (R2=0.71-0.99, except tegmens), and punicalagin (R2=0.71-1.00). This study provides a comparative analysis of the phenolic content and antioxidant activity in different organs of pomegranate, highlighting the placenta as the primary source of punicalagin. This study provides a theoretical basis for the development and utilization of pomegranate phenolic compounds.

Bacillus amyloliquefaciens Rescues Glycyrrhizic Acid Loss Under Drought Stress in Glycyrrhiza uralensis by Activating the Jasmonic Acid Pathway.

Drought is a major factor limiting the production of the perennial medicinal plant Glycyrrhiza uralensis Fisch. (Fabaceae) in Northwest China. In this study, 1-year-old potted plants were inoculated with the strain Bacillus amyloliquefaciens FZB42, using a gradient of concentrations (CFU), to test for microbe-induced host tolerance to drought condition treatments in a greenhouse experiment. At the concentration of 108 CFU ml–1, FZB42 had significant growth-promoting effect on G. uralensis: the root biomass was 1.52, 0.84, 0.94, and 0.38 times that under normal watering and mild, moderate, and severe drought stress conditions, respectively. Under moderate drought, the positive impact of FZB42 on G. uralensis growth was most pronounced, with both developing axial and lateral roots strongly associated with indoleacetic acid (IAA) accumulation. An untargeted metabolomic analysis and physiological measurements of mature roots revealed that FZB42 improved the antioxidant system of G. uralensis through the accumulation of proline and sucrose, two osmotic adjustment solutes, and by promoting catalase (CAT) activity under moderate drought stress. Furthermore, significantly higher levels of total flavonoids, liquiritin, and glycyrrhizic acid (GA), the pharmacologically active substances of G. uralensis, were found in the roots of inoculated plants after FZB42 inoculation under all imposed drought conditions. The jasmonic acid (JA) content, which is closely related to plant defense responses and secondary metabolites’ production, was greatly increased in roots after the bacterial inoculations, indicating that FZB42 activated the JA pathway. Taken together, our results demonstrate that inoculation with FZB42 alleviates the losses in production and pharmacological metabolites of G. uralensis caused by drought via the JA pathway’s activation. These results provide a developed prospect of a microbial agent to improve the yield and quality of medical plants in arid and semi-arid regions.

Enhancing the sensory attributes and antioxidant properties of snus by mixing it with tea

In the present work, we investigated the chemical and volatile compositions of three tea-containing snus samples, after which their acceptability on the aromatic and taste coordination was evaluated by a professional panel. Results showed that the tea-containing snus samples exhibited better acceptability on the aroma and taste coordination profiles. Dahongpao tea (DT)-containing snus (DT-snus) exhibited the best acceptability of aromatic coordination, whereas the most favourable taste coordination was exhibited by Keemun black tea (KBT)-containing snus (KBT-snus). The antioxidant activity determined by the DPPH and ABTS assays revealed that Lu’an Guapian tea (LGT)-containing snus (LGT-snus) exhibited the highest free-radical scavenging ability. LGT-snus was also found to have the highest content of total polyphenols, amino acids, and caffeine. The highest levels of total flavonoids and soluble sugars were found in DT-snus and KBT-snus, respectively. There were 88, 68, and 74 volatiles found in DT-snus, LGT-snus, and KBT-snus, respectively, among which, nitrogenous compounds constituted the major category. High levels of nicotine, megastigmatrienone, neophytadiene, nicotyrine, and cotinine, which are the major volatiles in snus, were detected in the tea-containing snus samples. The mixing of tea introduced the flavour profiles of the volatiles present in the original tea into the tea-containing snus samples. Benzaldehyde, β-ionone, hexanoic acid, 3-(Z)-hexenyl ester, pyrazines, and nerolidol from LGT; furfural, benzeneethanol, nerolidol, linalool, and cedrol from DT; and nonanal, geraniol, cis-jasmone, benzenemethanol, and methyl salicylate from KBT were found in high concentrations in the corresponding tea-containing snus samples.

Analyses of the Compositions, Antioxidant Capacities, and Tyrosinase-Inhibitory Activities of Extracts from Two New Varieties of Chrysanthemum morifolium Ramat Using Four Solvents

Chrysanthemum morifolium Ramat is traditionally used as both medicine and food in China. In this study, extracts of C. morifolium Ramat Hang Ju No. 1 (No. 1) and No. 2 (No. 2) were produced using four different solvents: 95% ethanol, ethyl acetate, n-hexane and distilled water. In total, eight types of extracts were analyzed for extraction yields and total flavonoids, polyphenols, glycans, reducing sugars, and chlorogenic acids. The antioxidant capacities and tyrosinase-inhibitory activities of these extracts were also determined. Among them, the ethanolic extract of No. 1 (No. 1A) had the highest levels of total flavonoids (16.71 mg rutin equivalent/g dry weight (DW)), polyphenols (7.07 mg gallic acid equivalent/g DW), and chlorogenic acids (6595.46 μg/g DW) and the water extract of No. 1 (No. 1D) had the highest levels of total glycans (9.24 mg/g DW), and reducing sugars (23.32 μg/g DW). In terms of antioxidant capacity, No. 1A (1.0 mg/mL) demonstrated the best 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging activity (96.2 ± 0.4%), ferrous ion chelating ability (55.44 ± 0.03%), and reducing power (0.988 ± 0.003). No. 1D (1.0 mg/mL) showed the highest tyrosinase inhibitory activity (39.34 ± 0.03%). From these results, high levels of total flavonoids and polyphenols correlate with antioxidant capacity. Moreover, high levels of total chlorogenic acid in No. 1A and No. 1D correlate with high levels of tyrosinase inhibitory activity. Therefore, No. 1A has the potential to be used in daily health drinks, foods and skin whitening products. These results can be applied to similar flower plant extracts.

Penentuan Aktivitas Antioksidan dan Kandungan Flavonoid Total Ekstrak Daun Papasan (Coccinia grandis L.) Berdasarkan Perbedaan Pelarut Polar

Papasan leaves have several properties, including antihyperglycemic, diabetes, antipyretic and antioxidant. Minor metabolite compounds that have the potential as antioxidants from this plant are flavonoids, alkaloids, saponins, and tannins. This study's purpose to determine the antioxidant activity and the flavonoid total contents of Papasan (Coccinia grandis L.) leaf extract based on the differences in polar solvents. The polar solvents used were ethanol, methanol, and water. Extraction used by maceration and dekokta. The antioxidant activity and the flavonoid total contents were established by UV-Vis spectrophotometry according to the decrease in absorbance at a maximum wavelength of 515 nm by the DPPH (2,2-diphenyl-1-picrylhydrazyl) method. Determination of antioxidant activity and the flavonoid total contents were excluded on quercetin comparisons. The values of IC50 and the flavonoid total contents in the ethanol extract respectively were 287.92 ppm and 49.825 mg QE/g while the IC50 values and total flavonoid levels in the extract of methanol were 73.29 ppm and 50.415 mg QE/g. In the extract of the water, the value of IC50 was 39.80 ppm and the total flavonoid contents were 50.415 mg QE/g. The conclusions of these studies were that the most antioxidant activity was found in water extract, while water and methanol extract had the same and highest levels of total flavonoids.

Qualidade fenólica em cultivares de uva submetida a poda verde e regulador hormonal

A cor e estabilidade das antocianinas em frutas são amplamente influenciadas pela temperatura, luz e pH. Neste sentido, o presente trabalho objetivou avaliar o manejo da desfolha e da aplicação do ácido abscísico (S-ABA) na qualidade fenólica das cultivares Primitivo e Malbec (Vitis vinifera L.). O experimento foi conduzido em um vinhedo comercial em Santa Catarina, Brasil, com duas cultivares de videira Primitivo e Malbec (V. vinífera L.), respectivamente, por dois ciclos consecutivos: 2015/2016 e 2016/2017. O delineamento experimental foi em blocos casualizados, consistindo em seis tratamentos: 1) testemunha (sem tratamento); 2) desfolha manual no início da maturação (DIM); 3) desfolha manual quinze dias após a primeira desfolha (D15); 4) S-ABA 200 mg L-1 (ABA200); 5) S-ABA 400 mg L-1 (ABA400); 6) S-ABA 600 mg L-1 (ABA600), quatro repetições e três plantas por parcela. Com os dados obtidos, realizou-se o teste de normalidade por Kolmogorov-Smirnov ao nível de 5% de significância, empregando a análise de variância (ANOVA) e, posteriormente, a Análise de Componentes Principais (ACP) com o objetivo de analisar a relação entre os parâmetros analisados, utilizando o software R. Após a discussão dos resultados, conclui-se que a aplicação exógena de S-ABA fornece níveis mais altos de flavonoides totais, luminosidade e cromaticidade em videiras cvs. Malbec e Primitivo e que a aplicação de S-ABA promoveu desfolha com 600 mg L-1, podendo ser uma alternativa para reduzir custos de produção. A desfolha forneceu um aumento na intensidade de cor e no ângulo Hue em bagas cv. Malbec e Primitivo, em que tal fator pode estar relacionado à maior incidência de radiação nos cachos, causada pela remoção das folhas.

A comparative study of essential oil constituents, total phenolics and antioxidant capacity of the different organs of four species of the genus bunium

AbstractBunium persicum is one of the fragrant herbaceous plants that has many nutritional and medicinal applications. Information about other species of Bunium is scarce. Essential oils, polyphenolics and antioxidant activity were analysed in four species of Bunium. The highest levels of total flavonoids were observed in leaves and fruits of B wolffii while the other polyphenolics did not show significant differences between the species and organs. Gas chromatography‐mass spectrometry (GC/MS) analysis revealed 16, 14, 14 and 13 main components respectively accounting for 97.52% of the entire essential oils of B cylindricum, 91.12% of B paucifolium, 97.14% B persicum and 96.41% of B wolffii. The monoterpenes content was 57.9, 22, 97.14 and 63.83% in B cylindricum, B paucifolium, B persicum and B wolffii respectively whereas sesquiterpenes levels were respectively 1.29, 27.45, 0.0 and 2.98%. The nonterpens constituted 38.33, 41.67, 0.0 and 29.6% in these four species respectively. The highest amount of monoterpenes (97.14%) was observed in B persicum, while the maximum of sesquiterpenes (27.45%) and nonterpenes (41.67%) obtained in B paucifolium. The main constituents were γ‐terpinene, myristicin, cuminaldehyde, apiole, α‐pinene, β‐pinene, β‐selinene, Z‐ β‐ocimene and γ‐terpinene‐7‐al. Cuminaldehyde with the pleasant odour was only revealed in B persicum. All organs of different species except corms showed high antioxidant activity using ABTS and DPPH assay. Thus, similar to B persicum, the other studied species are a rich source of antioxidant compounds and can be used as functional food ingredients and a potential source of natural antioxidants with valuable health benefits.

Comparison of Total Flavonoids Content in Different Bamboo Shoots and Different Parts

The paper determined the content of total flavonoids in different types and parts of rhizome shoot and winter bamboo shoots by UV spectrophotometry for comparison. The results showed that the bamboo shoot sheath had a higher level of total flavonoids than in the bamboo shoots, and the rhizome shoot had a higher level of total flavonoids than the winter bamboo shoots in different parts.

Kombinasi Fraksi Etil Asetat Jahe Merah (Zingiber officinale var. Rubrum) dan Jahe Emprit (Zingiber officinale var. Amarum) Sebagai Antioksidan

Red ginger and emprit ginger are plants that are known to have flavonoid compounds with various benefits including antioxidants. This study aims to determine the total flavonoid levels of the ethyl acetate fraction of red ginger and emprit ginger and the IC50 value using the DPPH (2,2-Diphenyl-1-Picrylhydrazil) method. The highest level of total flavonoids in the ethyl acetate fraction in red ginger was 4,434 mgQE/g extract while in ginger emprit was 11,072 mgQE/g extract. The combination of the ethyl acetate fraction of red ginger and emprit ginger showed very strong antioxidant activity with an IC50 value of 19,027 ppm (1:1 combination), 17,649 ppm (1:2 combination), and 13,711 ppm (2:1 combination).

Agrobacterium rhizogenes-mediated transformation enhances the antioxidant potential of Artemisia tilesii Ledeb.

Plants belonging to the genus Artemisia L. have been used for medicinal purposes since ancient times. These aromatic plants produce and accumulate a wide range of potent secondary metabolites, many of which have shown antioxidant, antiparasitic, antimicrobial, anti-inflammatory, and even anticancer activities. Enhanced biosynthesis of these compounds is a prerequisite for comprehensive studies of their therapeutic properties and cost-efficient use. Transformation of plants with Agrobacterium rhizogenes native root locus (rol) genes is a promising approach to increase the biosynthesis of plant secondary metabolites. The aim of the present study was to evaluate the effects of A. rhizogenes-mediated transformation on the flavonoid contents in hairy roots of medicinal herb A. tilesii Ledeb. Transgenic A. tilesii hairy root lines were analyzed for stable integration of the rolB and rolC transgenes into the plant genome, total flavonoid contents, antioxidant activities of extracts, and the spatiotemporal expression of two flavonoid biosynthetic genes, phenylalanine ammonialyase (PAL) and chalcone synthase (CHS). The flavonoid contents of A. tilesii directly correlated with the antiradical activity and reducing power of their respective lines, with the greatest antioxidant activity found in the plants with the highest level of total flavonoids. Furthermore, all hairy root lines demonstrated altered expression of plant native PAL and CHS genes. Most importantly, A. rhizogenes-mediated transformation enhanced the biosynthesis of natural antioxidants in A. tilesii, producing almost twice the amount of flavonoids than controls. These findings provide an opportunity for the identification of the bioactive molecules in A. tilesii extracts and their potential health benefits.

Genome sequencing provides insights into the evolution and antioxidant activity of Chinese bayberry

BackgroundChinese bayberry (Myrica rubra Sieb. & Zucc.) is an economically important fruit tree characterized by its juicy fruits rich in antioxidant compounds. Elucidating the genetic basis of the biosynthesis of active antioxidant compounds in bayberry is fundamental for genetic improvement of bayberry and industrial applications of the fruit’s antioxidant components. Here, we report the genome sequence of a multiple disease-resistant bayberry variety, ‘Zaojia’, in China, and the transcriptome dynamics in the course of fruit development.ResultsA 289.92 Mb draft genome was assembled, and 26,325 protein-encoding genes were predicted. Most of the M. rubra genes in the antioxidant signaling pathways had multiple copies, likely originating from tandem duplication events. Further, many of the genes found here present structural variations or amino acid changes in the conserved functional residues across species. The expression levels of antioxidant genes were generally higher in the early stages of fruit development, and were correlated with the higher levels of total flavonoids and antioxidant capacity, in comparison with the mature fruit stages. Based on both gene expression and biochemical analyses, five genes, namely, caffeoyl-CoA O-methyltransferase, anthocyanidin 3-O-glucosyltransferase, (+)-neomenthol dehydrogenase, gibberellin 2-oxidase, and squalene monooxygenase, were suggested to regulate the flavonoid, anthocyanin, monoterpenoid, diterpenoid, and sesquiterpenoid/triterpenoid levels, respectively, during fruit development.ConclusionsThis study describes both the complete genome and transcriptome of M. rubra. The results provide an important basis for future research on the genetic improvement of M. rubra and contribute to the understanding of its genetic evolution. The genome sequences corresponding to representative antioxidant signaling pathways can help revealing useful traits and functional genes.

Isolation and molecular identification for autochthonous starter Saccharomyces cerevisiae with low biogenic amine synthesis for black raspberry (Rubus coreanus Miquel) wine fermentation.

Biogenic amines (BAs) are widely present in nearly all fermented foods and beverages, and excess consumption can cause adverse health effects. To prepare BA-free Korean black raspberry wine (BRW), four autochthonous starter yeast strains without hazardous BA synthesis activity were selected and their physiological and biochemical properties were examined. The selected strains were identified as Saccharomyces cerevisiae based on 26S rDNA sequencing and microsatellite analysis. Molecular fingerprinting revealed that isolates were quite different from commercial wine yeast S. cerevisiae (52.4% similarity), but genetically relevant to commercial beer yeasts. The four S. cerevisiae strains produced over 10% ethanol during BRW fermentation. In addition, the fermented BRW with these strains showed higher levels of total flavonoids and similar antioxidant activity compared to the control sample. Potentially hazardous BAs that commonly occur in black raspberry extract (BRE) such as cadaverine, histamine, and spermidine were also not detected in the fermented BRW. Thus, we suggest that our strains are promising fermentation tools to ensure high quality and enhanced functionality in the production of BA-free BRW.

Bacillus pumilus alleviates drought stress and increases metabolite accumulation in Glycyrrhiza uralensis Fisch.

Drought is a major limiting factor of plant productivity worldwide and its incidence is predicted to increase with climate changing. Endophytes are non-pathogenic plant-associated bacteria that can play an significant role in improving plant tolerance to drought. Here, the effects of Bacillus pumilus (B. pumilus) inoculation on growth, metabolite accumulation and related protein expression, and it’s mechanism focusing on antioxidant defense of Glycyrrhiza uralensis Fisch. (G. uralensis) subjected to drought stress were investigated under controlled conditions. Drought stress induced oxidative damage and further decreased growth and secondary metabolites in G. uralensis. Exposure of inoculated plant to drought-stress led to significant increase in total biomass by 34.9%, and in oxygen species and antioxidants while decrease in lipid peroxidation level, compared to non-inoculated plants grown under similar conditions. There was a significant effect of the endophyte on plant metabolism; higher levels of total flavonoids, total polysaccharide and glycyrrhizic acid were recorded in roots of colonized plants compared to non-colonized ones. Furthermore, the expression of HMGR, SQS and β-AS, key enzymes for glycyrrhizic acid synthesis, significantly increased by B. pumilus inoculation. Taken together, our results indicated that B. pumilus improves G. uralensis growth under drought stress through the modification of antioxidants accumulation and enhances glycyrrhizic acid content by the incremental expression of key enzymes. These results will contribute to the development of a microbial agent to improve the yield and quality of medical plants exposed to environmental stresses.

Pre-fermentative cold maceration in presence of non-Saccharomyces strains: Evolution of chromatic characteristics of Sangiovese red wine elaborated by sequential inoculation

Two different Metschnikowia strains (M. pulcherrima MP 346 or M. fructicola MF 98-3) were applied for the first time, during pre-fermentative cold maceration (PCM) in order to enhance the properties and stability of Sangiovese wine color. During the 2014 and 2015 vintages a total of eight wines were produced with 24 h of cold maceration (PCM 24 h) or 72 h (PCM 72 h), respectively. PCM was carried out in presence of MP 346 or MF 98-3 or pectic enzyme (Cuvée Rouge). The sequential inoculation of S. cerevisiae strain was carried out at the end of PCM. After 12 months in the bottle, the MP 346 and MF 98-3 wines contained much higher levels of total flavonoids than the Control sample for both vintages and regardless PCM duration. Moreover, in both vintages only MF 98-3 showed a higher color intensity than the Control sample after 12 months in the bottle. However, neither PCM duration nor the microbial/enzymatic treatment increased the level of anthocyanins at draining off. Both wines produced by the pre-fermentative inoculum with Metschnikowia strains (MP 346 and MF 98-3) retained their red hue, regardless the duration of pre-fermentative and fermentative macerations, while the Control wines were characterized by faster rates of color loss.

Comparative Evaluation of Phytochemicals, and Antidiabetic and Antioxidant Activities of Cuscuta reflexa Grown on Different Hosts in Northern Thailand

For the first time, total phytochemical profiles of methanol crude extracts of Cuscuta reflexa grown on three different hosts, Coccinia grandis, Ficus racemosa- and Samanea saman, that were cultivated in northern Thailand were examined, along with their antidiabetic and antioxidant activities. The highest level of total flavonoids (114.4 mg QE/ g extract) and total phenolic content (90.8 mg GAE/ g extract) were observed in the extract of Cu. reflexa that was grown on Co. grandis. The GC-MS results showed that various types of phenolic compounds, hydrocarbons, saturated fatty acids and methyl ester of fatty acids, unsaturated fatty acids and methyl ester of fatty acids, vitamin E, terpenes and sterol contained in the extracts of Cu. reflexa were-capable of being grown on three hosts. Moreover, the HPLC results showed the presence of gallic acid, catechin, vanillic acid, rutin and quercetin in all Cu. reflexa samples The extract of Cu. reflexa that was grown on Co. grandis represented the highest antidiabetic activity with a percent inhibition of 51.2. Moreover, the extract also possessed the greatest antioxidant activity (DPPH; IC₅₀ 168.6 μg/mL, FRAP; 40.5 mg GAE/ g extract).

Low concentration of sodium bicarbonate improves the bioactive compound levels and antioxidant and α-glucosidase inhibitory activities of tartary buckwheat sprouts.

This study aimed to investigate the effects of different concentrations of sodium bicarbonate (NaHCO3) on the accumulation of flavonoids, total phenolics and d-chiro-inositol (DCI), as well as the antioxidant and α-glucosidase inhibitory activities, in tartary buckwheat sprouts. Treatment with low concentrations of NaHCO3 (0.05, 0.1, and 0.2%) resulted in an increase in flavonoids, total phenolic compounds and DCI concentrations, and improved DPPH radical-scavenging and α-glucosidase inhibition activities compared with the control (0%). The highest levels of total flavonoids (26.69mg/g DW), individual flavonoids (rutin, isoquercitrin, quercetin, and kaempferol), total phenolic compounds (29.31mg/g DW), DCI (12.56mg/g DW), as well as antioxidant and α-glucosidase inhibition activities, were observed in tartary buckwheat sprouts treated with 0.05% NaHCO3 for 96h. These results indicated that appropriate treatment with NaHCO3 could improve the healthy benefits of tartary buckwheat sprouts.

Antioxidants and sensory properties of the infusions of wild passiflora from Brazilian savannah: potential as functional beverages.

The study of biodiversity for species recovery and sustainable use has encouraged research with plants from Brazilian savannah. We aimed to characterize chemical and sensory properties of infusions of passifloras, due to their potential as functional beverages. Infusions and hydroalcoholic extracts of four species of wild passifloras, three varieties of Passiflora edulis and a commercial passiflora tea were evaluated for total phenolics (TPs), total flavonoids (TFs), condensed tannins (CTs), and antioxidant activity (DPPH and FRAP). Free-choice Profile and acceptance, compared with green tea, were performed for sensory characterization. In general, infusions had higher levels of TPs and CTs than hydroalcoholic extracts, which in turn had higher levels of TFs. Infusion of P. nitida showed higher amounts of TPs and antioxidant activity. Acceptance of passiflora infusions was similar or higher than that of green tea, except for P. alata. P. setacea presented a sensory profile similar to other commercial teas and higher acceptance by a group of consumers. Passiflora infusions showed different degrees of suitability as acceptable functional beverage. Identification of phenolics and other bitter compounds is needed to understand the intense bitterness of P. alata, as it did not present the highest contents of TPs, CTs and TFs.

Antioxidant Activities and Polyphenolic Constituents of Bitter Bean Parkia Speciosa

Bitter bean (Parkia speciosa), also known as petai, is a popular non-timber forest product. Traditionally, its fruits are consumed as vegetables and herbal medicines in Malaysia. The present study aimed to evaluate the antioxidant activities of aqueous and ethanol extracts of P. speciosa empty pods using various antioxidant assays, as well as examining their polyphenolic constituent contents. Results showed that with the exception of superoxide radical scavenging activity, ethanol extracts possessed stronger DPPH and ABTS radical scavenging, anti-lipid peroxidation, metal chelating and reducing power activities than aqueous extracts. It was found to contain a higher level of total flavonoids and total phenols than aqueous extracts. The major polyphenolic constituents present in these extracts were gallic acid, catechin, ellagic acid, and quercetin. Although aqueous extracts contained a higher level in gallic acid, its catechin, ellagic acid, and quercetin contents were lower than ethanol extracts. Taken together, the higher amount of polyphenolic compounds present in ethanol extracts could have contributed to its stronger antioxidant activities than aqueous extracts; these results also provided the chemical basis for certain health benefits claimed of P. speciosa empty pods in folk medicine and as foods.

Flavonoid compositions and antioxidant activity of calamondin extracts prepared using different solvents

Calamondin has been demonstrated to exhibit antioxidant function and tyrosinase inhibitory activity, which might be attributed to its flavonoid compounds. To improve their application, the flavonoid compositions and antioxidant activity of calamondin extracts, prepared by different solvents, were investigated. The results showed that total phenolic and flavonoid contents of extracts from peel of calamondin were higher than that from pulp, except the flavonoid content in hot water extract. The flavonoids found in extracts of calamondin were 3′,5′-di-C-β-glucopyranosylphloretin (DGPP), naringin, hesperidin, nobiletin, tangeretin, and diosmin. DGPP exhibited the highest quantity, while naringin and hesperidin were the other two major flavonoids. The content of DGPP in hot water extract of peel was higher than in extracts of organic solvents, however, the contents of nobiletin and tangeretin were found only in extracts of organic solvents. The highest levels of total flavonoids and DGPP were obtained in hot water extract from peel at 90°C. The extracts of hot water and ethyl acetate showed higher 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging potency than that of ethanol and methanol. A positive relationship existed between total phenolic contents and DPPH scavenging potency (p < 0.01), while total flavonoid compositions also showed correlation (p < 0.05). Thus, DGPP, naringin, and hesperidin might contribute to antioxidant activity. Collectively, the hot water extract of calamondin peel might have potential for health food and cosmetic applications due to its good antioxidant activity and high level of DGPP.