Major Flavone Research Articles

Camel Whey Protein and Baicalein Suppressed Mast Cell Degranulation in Mice Models of IgE- and Non-IgE-Mediated Anaphylaxes: Potential Mechanisms on Downstream Cell Signaling of Mast Cells

ABSTRACT Introduction Novel treatments are being researched to develop more safe and effective protective medications for anaphylaxis. Camel whey protein (CWP) and baicalein (BAC, one of the major flavones) have multiple beneficial properties including anti-inflammatory and antioxidant activities. Methods The current study investigated/compared the therapeutic protection of repeated intragastric administration of CWP (100 mg/kg body weight, as an animal extract) and BAC (10 mg/kg body weight, as a plant extract), before the challenge with ovalbumin (OVA) or receiving the compound 48/80 (C48/80), against mice models for IgE-independent and dependent anaphylaxes. Besides, their effects on mast cells (MCs) downstream cell signaling were explored. Results The results revealed that CWP and BAC reduced the mortality rate, as compared with a MCs stabilizer “sulfasalazine (SSZ, 100 mg/kg body weight, intraperitoneally),” in both mice models. Furthermore, they prevented the MCs degranulation and significantly reduced (p < .05) lung tissue levels of cell signaling (p-AKT, p-ERK, and p-IκBα). Additionally, they decreased histamine, tryptase, leukotriene C4, prostaglandin D2, interleukin (IL)-4, and IL-10 levels in broncho-alveolar and peritoneal lavages in systemic anaphylaxis mice models. They also restored the stabilization of peritoneal MCs membrane in inverted light microscopy results accompanied by amelioration of the lung histology. Discussion The present study provided evidence for the protective therapeutic effect of CWP and BAC against anaphylaxis. As a result, CWP and BAC may be used as preventative supplemented regimens for both non-vegetarian and vegetarian consumers to treat allergy through downregulation of MCs signal transduction pathways, and hence controlling the production of inflammatory mediators.

The dynamic changes in pigment metabolites provide a new understanding of the colouration of Pyracantha fortuneana at maturity

The type, content and accumulation characteristics of pigments are the material basis for fruit colour and the evaluation basis of the fruit maturity and nutritional value of P. fortuneana. However, little information is available on the changes in carotenoids, anthocyanins, procyanidins and major flavones during the ripening process of P. fortuneana fruits. Thus, this study investigated the colour conversion characteristics, the main changes in the above four metabolites and the association landscape with those metabolites. The results showed that thirty-nine kinds of carotenoids and derivatives, eighteen anthocyanins, five procyanidins and five flavone compounds were identified in the fruits of P. fortuneana. The total content and contents of most individual carotenoids, anthocyanins, procyanidins and flavones reached the highest values at the TS2, TS4, TS1 and TS1 stages, respectively. Among the variations, the contents of β-carotene and lutein increased first and then decreased, cyanidin-3-galactoside and cyanidin-3-glucoside accumulated, the concentrations of procyanidin C1 and procyanidin B2 decreased, and the contents of rutin and quercetin-3-O-glucoside also decreased; these changers were responsible for the main changes in carotenoids, anthocyanidin, procyanidins and flavones, respectively. For the correlation analysis results, there might be two modes of action that together affected the colour conversion of P. fortuneana fruits during ripening, i.e., (E/Z)-phytoene communicated with the carotenoid metabolic pathway that might promote the accumulated ABA content, which might cause the increased anthocyanidin (primarily through cyanidin-3-(6-malonyl-beta-d-glucoside) (C3MG)) at the final stage; most of the decreased flavone and procyanidin metabolites produced by the flavonoid metabolic pathway were another important factor affecting the accumulation of C3MG.

Highly oxidized flavones in Artemisia species – structure revisions and improved UHPLC-MSn analysis

In course of our studies of the aerial parts of Artemisia abrotanum the major methoxyflavonol could be isolated. However, by NMR structural analysis it became obvious that the substitution pattern in ring B differs from reports for casticin (2). The position of methoxyl and hydroxyl groups are interchanged, i.e., the major flavone is actually chrysosplenetin (1). Three structures in A. abrotanum and A. frigida had to be revised. Use of pyridine-d5 instead of DMSO‑d6 made the resolution of the B-ring 1H and 13C NMR signals possible and enabled correct structural assignment by 2D NMR experiments.Results from NMR structure elucidation for A. abrotanum were confirmed by LC-PDA-ESI-MSn analysis when a PFP (pentafluorophenyl) stationary phase with an optimized gradient elution was applied for separation of 1 and 2 instead of a corresponding C-18 phase. Electrospray mass spectrometry (positive and negative mode) with subsequent fragmentation (ESI-MSn) revealed distinctive mass spectral features of both compounds, especially at MS4 level. Several Artemisia extracts including A. annua were analysed on the PFP phase for the presence of 1 and 2.

Determination of Phytochemical Contents in Extracts from Different Growth Stages of Oroxylum indicum Fruits Using HPLC-DAD and QAMS Methods.

Flavones are major compounds found in several parts of Oroxylum indicum (O. indicum). The quantification of multiple components by one marker (QAMS) method and the high-performance liquid chromatography (HPLC) method were developed for the quantitative analysis of extracts from the young fruits, green mature fruits, dry pod coats and seeds of O. indicum. Oroxin A, oroxin B and chrysin-7-O-glucuronide were identified in the O. indicum extracts. Oroxylin A and 5-hydroxymethylfurfural were isolated and structurally identified from the pod coat and young fruit extracts, respectively. From the HPLC analysis of the seven major flavones in the extracts, baicalin was the major compound in all extracts investigated (0.4-11% w/w of the extract). All flavone contents were low in the young fruit extract (<1% w/w of the extract). The green mature fruit and dry pod coat extracts showed similar constituent compositions. They contained small amounts of baicalin and oroxylin A, which were found only in these two extracts. Oroxylin A could be used as a marker to indicate the maturity of O. indicum fruits, while 5-hydroxymethylfurfural could be used as a marker for the young fruits. Baicalin was found to be a suitable single marker to calculate the contents of all flavones in the O. indicum extracts.

How do barley plants with impaired photosynthetic light acclimation survive under high-light stress?

Main ConclusionWHIRLY1 deficient barley plants surviving growth at high irradiance displayed increased non-radiative energy dissipation, enhanced contents of zeaxanthin and the flavonoid lutonarin, but no changes in α-tocopherol nor glutathione.Plants are able to acclimate to environmental conditions to optimize their functions. With the exception of obligate shade plants, they can adjust their photosynthetic apparatus and the morphology and anatomy of their leaves to irradiance. Barley (Hordeum vulgare L., cv. Golden Promise) plants with reduced abundance of the protein WHIRLY1 were recently shown to be unable to acclimatise important components of the photosynthetic apparatus to high light. Nevertheless, these plants did not show symptoms of photoinhibition. High-light (HL) grown WHIRLY1 knockdown plants showed clear signs of exposure to excessive irradiance such as a low epoxidation state of the violaxanthin cycle pigments and an early light saturation of electron transport. These responses were underlined by a very large xanthophyll cycle pool size and by an increased number of plastoglobules. Whereas zeaxanthin increased with HL stress, α-tocopherol, which is another lipophilic antioxidant, showed no response to excessive light. Also the content of the hydrophilic antioxidant glutathione showed no increase in W1 plants as compared to the wild type, whereas the flavone lutonarin was induced in W1 plants. HPLC analysis of removed epidermal tissue indicated that the largest part of lutonarin was presumably located in the mesophyll. Since lutonarin is a better antioxidant than saponarin, the major flavone present in barley leaves, it is concluded that lutonarin accumulated as a response to oxidative stress. It is also concluded that zeaxanthin and lutonarin may have served as antioxidants in the WHIRLY1 knockdown plants, contributing to their survival in HL despite their restricted HL acclimation.

C-Glycosidic flavone-rich Passiflora incarnata L. leaf extracts decrease body weight and fatty liver in obese mice

Passiflora incarnata L. is known to contain abundant C-glycosyl flavones, which exhibit various biological activities; however, its anti-obesity effects have not yet been investigated. To this end, herein, we conducted UPLC-MS/MS to identify flavonoids in Passiflora incarnata L. aqueous and 60% ethanol extracts (denoted as PAE and PEE, respectively) and HPLC to quantify five major C-glycosyl flavones (vitexin, isovitexin, orientin, isoorientin, and vicenin-2). PEE contained most of the C-glycosyl flavones compared to PAE. The analysis of the inhibitory effect on lipid accumulation of these extracts and the five C-glycosyl flavones were conducted using differentiated 3T3-L1 and oleic acid (OA)-treated HepG2 cells. PEE more effectively inhibited lipid accumulation than PAE. Among C-glycosyl flavones, vicenin-2 showed the strongest lipid accumulation inhibitory effect in both cells and significantly inhibited lipid-metabolism-related FAS, PPARγ, FABP4, and SREBP1c. Moreover, we fed a high-fat diet (HFD) containing PEE to C57BL/6 mice for eight weeks and measured the body weight, serum lipid, hepatic lipid, and adipocyte size. The results showed that PEE reduced body weight gain and serum lipids in HFD-fed mice. PEE suppressed hepatic lipid accumulation and adipocyte size by suppressing adipogenesis and lipogenesis. Our results demonstrated that C-glycosyl-flavone-rich PEE can be used as an anti-obesity agent.

Combined transcriptomic and metabolomic analyses identifies CsERF003, a citrus ERF transcription factor, as flavonoid activator

Transcription factor (TF) modulation is a promising strategy for plant flavonoid improvement. Here, we observed evident decreases in some major flavones and flavonols and the expression of some key related genes in a ‘Newhall’ navel orange mutant (MT) relative to the wild type (WT). A consistently downregulated ERF TF CsERF003 in MT could increase the contents of major flavonoids and the precursor phenylalanine when transiently overexpressed in citrus fruit. Overexpression of CsERF003 in ‘Micro-Tom’ tomato (OE) resulted in a darker and redder fruit color than wild type ‘Micro-Tom’ (WTm). Two major flavonoids, naringeninchalcone and kaempferolrutinoside, were averagely induced by 7.99- and 36.83-fold in OEs, respectively, while little change was observed in other polyphenols, such as caffeic acid, ferulic acid, and gallic acid. Key genes involved in the initiation of phenylpropanoid (PAL, 4CH, and 4CL) and flavonoid (CHS and CHI) biosynthesis were up-regulated, while most genes participating in the biosynthesis of other polyphenols, such as HCT and CCR, were down-regulated in OEs. Therefore, it could be concluded that carbon flux floods into the phenylpropanoid biosynthetic pathway and is then specifically directed for flavonoid biosynthesis. CsERF003 may be a potentially promising gene for fruit quality improvement and engineering of natural flavonoid components.

Baicalin induces ferroptosis in osteosarcomas through a novel Nrf2/xCT/GPX4 regulatory axis

BackgroundOsteosarcomas (OS) is a kind of malignant bone tumor which occurs primarily in children and adolescents, and the clinical therapeutics remain disappointing. As a new programmed cell death, ferroptosis is characterized by iron dependent and intracellular oxidative accumulation, which provides a potential alternative intervene for the OS treatment. Baicalin, a major bioactive flavone derived from traditional Chinese medicine Scutellaria baicalensis, has been proved to have anti-tumor properties in OS. Whether ferroptosis participated in the baicalin mediated anti-OS activity is an interesting project. PurposeTo explore the pro-ferroptosis effect and mechanisms of baicalin in OS. Methods/study designPro-ferroptosis effect of baicalin on cell death, cell proliferation, iron accumulation, lipid peroxidation production was determined in MG63 and 143B cells. The levels of glutathione (GSH), oxidized (GSSG) glutathione and malondialdehyde (MDA) were determined by enzyme linked immunosorbent assay (ELISA). The expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2), Glutathione peroxidase 4 (GPX4) and xCT were detected by western blot in baicalin-mediated ferroptosis regulation. In vivo, a xenograft mice model was adopted to explore the anticancer effect of baicalin. ResultsIn the present study, it was found that baicalin significantly suppress tumor cell growth in vitro and in vivo. By promoting the Fe accumulation, ROS formation, MDA production and suppressing the ratio of GSH/GSSG, baicalin was found to trigger ferroptosis in OS and ferroptosis inhibitor ferrostatin-1 (Fer-1) successfully reversed these suppressive effects, indicating that ferroptosis participated in the baicalin mediated anti-OS activity. Mechanistically, baicalin physically interacted with Nrf2, a critical regulator of ferroptosis, and influenced its stability via inducing ubiquitin degradation, which suppressed the Nrf2 downstream targets GPX4 and xCT expression, and led to stimulating ferroptosis. ConclusionsOur findings for the first time indicated that baicalin exerted anti-OS activity through a novel Nrf2/xCT/GPX4-dependent ferroptosis regulatory axis, which hopefully provides a promising candidate for OS treatment.

Interactive network pharmacology and electrochemical analysis reveals electron transport-mediating characteristics of Chinese medicine formula Jing Guan Fang

BackgroundJing Guan Fang (JGF) is an anti-COVID-19 Chinese Medicine decoction comprised of five medicinal herbs to possess anti-inflammatory and antiviral properties for treatment. This study aims to electrochemically decipher the anti-coronavirus activity of JGF and show that microbial fuel cells may serve as a platform for screening efficacious herbal medicines and providing scientific bases for the mechanism of action (MOA) of TCMs. MethodsElectrochemical techniques (e.g., cyclic voltammetry) and MFCs were adopted as the bioenergy-based platforms to assess the bioenergy-stimulating characteristics of JGF. Phytochemical analysis correlated polyphenolic and flavonoid content with antioxidant activity and bioenergy-stimulating properties. Network pharmacology on the active compounds was employed to identify anti-inflammatory and anti-COVID-19 protein targets, and molecular docking validated in silico results. Significant findingsThis first-attempt results show that JGF possesses significant reversible bioenergy-stimulation (amplification 2.02 ± 0.04) properties suggesting that its antiviral efficacy is both bioenergy-steered and electron mediated. Major flavonoids and flavone glycosides identified by HPLC (e.g., baicalein and baicalin, respectively) possess electron-shuttling (ES) characteristics that allow herbal medicines to treat COVID-19 via (1) reversible scavenging of ROS to lessen inflammation; (2) inhibition of viral proteins; and (3) targeting of immunomodulatory pathways to stimulate the immune response according to network pharmacology.

Anti-inflammatory and antiviral activities of flavone C-glycosides of Lophatherum gracile for COVID-19.

Lophatherum gracile (L. gracile) has long been used as a functional food and herbal medicine. Previous studies have demonstrated that extracts of L. gracile attenuate inflammatory response and inhibit SARS-CoV-2 replication; however, the underlying active constituents have yet to be identified. This study investigated the bioactive components of L. gracile. Flavone C-glycosides of L. gracile were found to dominate both anti-inflammatory and antiviral effects. A simple chromatography-based method was developed to obtain flavone C-glycoside-enriched extract (FlavoLG) from L. gracile. FlavoLG and its major flavone C-glycoside isoorientin were shown to restrict respiratory bursts and the formation of neutrophil extracellular traps in activated human neutrophils. FlavoLG and isoorientin were also shown to inhibit SARS-CoV-2 pseudovirus infection by interfering with the binding of the SARS-CoV-2 spike on ACE2. These results provide scientific evidence indicating the efficacy of L. gracile as a potential supplement for treating neutrophil-associated COVID-19.

Purification Process and In Vitro and In Vivo Bioactivity Evaluation of Pectolinarin and Linarin from Cirsium japonicum.

Pectolinarin and linarin are two major flavone O-glycosides of Cirsium japonicum, which has been used for thousands of years in traditional Chinese medicine. Pharmacological research on pectolinarin and linarin is meaningful and necessary. Here, a process for the purification of pectolinarin and linarin from C. japonicum was established using macroporous resin enrichment followed by prep-HPLC separation. The results show the purity of pectolinarin and linarin reached 97.39% and 96.65%, respectively. The in vitro bioactivities result shows the ORAC values of pectolinarin and linarin are 4543 and 1441 µmol TE/g, respectively, meanwhile their inhibition rate of BSA-MGO-derived AGEs is 63.58% and 19.31% at 2 mg/mL, which is 56.03% and 30.73% in the BSA-fructose system, respectively. The COX-2 inhibition rate at 50 µg/mL of linarin and pectolinarin reached 55.35% and 40.40%, respectively. Furthermore, the in vivo bioassay combining of histopathologic evaluation and biochemical analysis of liver glutamic oxaloacetic transaminase, serum creatinine and TNF-α show pectolinarin can alleviate lipopolysaccharide (LPS)-induced acute liver and kidney injury in mice. Metabolomics analysis shows that pectolinarin attenuates LPS-challenged liver and kidney stress through regulating the arachidonic acid metabolism and glutathione synthesis pathways. Collectively, our work presents a solid process for pectolinarin and linarin purification and has discovered a promising natural therapeutic agent-pectolinarin.

Impact of Blue Light on Plant Growth, Flowering and Accumulation of Medicinal Flavones in Scutellaria baicalensis and S. lateriflora

Scutellaria baicalensis Georgi (Baikal skullcap) and S. lateriflora (American skullcap) are two ethnobotanical medicinal plants used to treat gastrointestinal, respiratory, and inflammatory disorders, in addition to demonstrated anti-cancer properties. The predominant bioactive compounds produced in these species are unique 4′-deoxyflavones, in roots of S. baicalensis and leaves of S. lateriflora, making these two species suitable to study the effects of light quality on flavone accumulation in aerial and underground tissues. Light emitting diodes were used to study the impact of blue-dominated spectrum on the accumulation of bioactive flavones. Eight major flavones, including 4′-deoxyflavones baicalein, wogonin, baicalin, wogonoside and chrysin, along with 4′-hydroxyflavones scutellarein, scutellarin and apigenin, were quantified using HPLC in high flavone accumulating tissues. Aerial tissues directly exposed to blue light in S. lateriflora showed an increase in the concentrations of scutellarein by 18.7%, scutellarin by 296%, and baicalin by 31.6%. While the roots in S. baicalensis also had significant increases in baicalein by 154% and wogonin by 76% in response to blue light, there was a slight reduction in their respective glycosides baicalin and wogonoside as well as a decrease in total flavone content. Blue light resulted in compact skullcap plants with early flowering and modified flavone profiles.

Baicalin Mitigates the Neuroinflammation through the TLR4/MyD88/NF-κB and MAPK Pathways in LPS-Stimulated BV-2 Microglia.

Baicalin (BA) is a major flavone from Scutellaria baicalensis Georgi and has showed significant curative effects in Parkinson's and Alzheimer's diseases. In the present study, we investigated the effects of BA on antineuroinflammation and related signaling cascade in lipopolysaccharide- (LPS-) induced BV-2 microglial model. The results showed that BA significantly attenuated inflammatory mediators (NO, iNOS, IL-1β, COX-2, and PGE2) and suppressed the expression of miR-155. More crucially, BA could regulate the expression of related proteins in Toll-like receptor 4 (TLR4)/myeloid differentiation protein 88 (MyD88)/nuclear factor κB (NF-κB) pathway and suppress the phosphorylation of mitogen-activated protein kinase (MAPK) family. In addition, molecular docking analysis indicated that BA binds to the amino acids Lie 63 and Tyr 65 of TLR4 by π-σ and π-π T-shaped interaction. Thus, BA suppressed the LPS-stimulated neuroinflammation in BV-2 microglia by blocking the TLR4-mediated signal transduction through TLR4/MyD88/NF-κB and MAPK pathways and inhibiting the miR-155 expression. Our findings demonstrated that BA could be a valuable therapeutic for the treatment of neuroinflammation and neurodegenerative diseases.

Antioxidant Capacities and Enzymatic Inhibitory Effects of Different Solvent Fractions and Major Flavones from Celery Seeds Produced in Different Geographic Areas in China.

To extend the application of celery (Apium graveolens L.) seeds, the antioxidant and enzymatic inhibitory activities of different fractions and their main flavones were investigated. The n-butanol fractions possessed the highest total phenolic content (TPC) and total flavonoid content (TFC) values. The n-butanol fractions from Northeast China samples exhibited the strongest free radical scavenging (DPPH IC50 = 20.27 μg/mL, ABTS IC50 = 15.11 μg/mL) and ferric reducing antioxidant power (FRAP 547.93 mg trolox (TE)/g) capacity, while those collected from Hubei China showed the optimal cupric reducing antioxidant capacity (CUPRAC) values (465.78 mg TE/g). In addition, the dichloromethane fractions from Jiangsu samples displayed a maximum Fe2+ chelating capacity (20.81 mg ethylene diamine tetraacetic acid (EDTA)/g). Enzyme level experiments indicated polyphenolic compounds might be the main hypoglycemic active components. Subsequently, the enzyme inhibitory activity of nine main flavones was evaluated. Chrysoeriol-7-O-glucoside showed better α-glucosidase inhibitory activity than others. However, apigenin showed the best inhibitory effect on α-amylases, while the presence of glycosides would reduce its inhibitory effect. This study is the first scientific report on the enzymatic inhibitory activity, molecular docking, and antioxidant capacity of celery seed constituents, providing a basis for treating or preventing oxidative stress-related diseases and hyperglycemia.

Latest research progress on anticancer effect of baicalin and its aglycone baicalein.

Cancer, which is a leading cause of deaths around the world, is characterized by genetic mutations and epigenetic changes. Baicalin and its aglycone baicalein, the major bioactive flavones derived from the dried root of Scutellaria baicalensis Georigi, belong to flavonoid compounds. Many studies demonstrated that both of them exhibited remarkable promising anticancer activities. This study summarized potential anticancer mechanisms of baicalin and baicalein including induction of apoptosis, initiation of cell cycle arrest, suppression of metastasis, induction of autophagy, and regulation of immunity. Combination strategies involving baicalin or baicalein as chemotherapeutic adjuvants, clinical trial and safety were also discussed. In addition, we compared the difference in their anticancer effects. Interestingly, baicalein showed quicker and stronger inhibitory effects on multiple cancers than those of baicalin, probably due to its smaller size and high lipophilicity which contribute to fast absorption and improve ability to penetrate cells. Taken together, both baicalin and baicalein are effective in treating cancer with good tolerance. However, deglycosylation of baicalin to baicalein was found to have stronger anticancer potential.

Nonselective Cell Necrosis Mediated by the Total Flavones of Penthorum Chinensis Pursh and Thonningianin-A in Human Hepatic and Hepatoma Cells

Penthorum chinensis Pursh (PCP), family Penthoraceae, has been used for hundreds of years in China. With the launch of PCP tablets, clinical applications focused on liver fibrosis and hepatocarcinoma. The purpose of this research was to explore the selectivity and toxicity of the active pharmacodynamic ingredients of PCP in vitro. The total flavones of PCP (TFPCE) and thonningianin-A (Th-A), a major flavone in TFPCE, were investigated on the cell death patterns in human hepatoma cells (HepG2) and human hepatic cells (LO2), followed by a concentration detection of LDH in the supernatants. Apoptosis and necrosis detection kits were used to validate the patterns of cell death caused by TFPCE and Th-A. Finally, the cytotoxicity of both TFPCE and Th-A were reproduced in the colorectal adenocarcinoma cells (NCI-H716). The results indicated that TFPCE inhibits the cell viability of HepG2 cells at a concentration lower than 25 μg/mL. Alternatively, the cell viability of LO2 cells dramatically decreased in the treatment of TFPCE at 25 μg/mL. The effects of Th-A on the cell viability of HepG2 cells and LO2 cells were consistent with TFPCE. LDH detection indicated that TFPCE and Th-A increased the LDH concentration of the supernatants in a dose-dependent way, indicating the pattern of cell necrosis. Fluorescence staining verified the necrosis cell death caused by TFPCE and Th-A. A dose-dependent tendency was obtained in NCI-H716 cells, indicating that the cell viability of NCI-H716 cells was significantly suppressed with the treatment of TFPCE and Th-A. Our results bring the potential toxicity of PCP to the forefront of public attention. Therefore, the clinical application of P chinensis is required to focus more on its cytotoxic effect.

Baicalein protects against MPP+/MPTP-induced neurotoxicity by ameliorating oxidative stress in SH-SY5Y cells and mouse model of Parkinson’s disease

Baicalein, a major bioactive flavone constituent isolated from Scutellaria baicalensis Georgi, has neuroprotective properties in several neurological disorders. Many studies suggest that oxidative stress plays a central role in the pathogenesis of Parkinson’s disease (PD). Baicalein has also been shown to have antioxidant effects. Therefore, the current study was designed to investigate whether baicalein could protect against MPP+/MPTP-induced neurotoxicity via suppressing oxidative stress in vitro and in vivo. In vitro, our results showed that baicalein increased cell viability in MPP+-treated SH-SY5Y cells. Treatment with baicalein could reversed the increased MDA and ROS levels, and the decreased GSH levels in MPP+-treated SH-SY5Y cells. In MPTP-treated mice, baicalein ameliorated MPTP-induced motor impairment and suppressed the MPTP-induced accumulation of iron and lipid peroxides. Besides, baicalein improved the neurotoxicity induced by MPTP as seen by a significant raise of tyrosine hydroxylase (TH) and simultaneous decrease of monoamine-oxidase-B (MAO-B). The inhibitory effect of baicalein on oxidative stress probably was partially governed by inhibition of ERK activation. In conclusion, our results suggest that baicalein could prevent MPP+/MPTP-induced neurotoxicity via suppressing oxidative stress.

Evaluation of parsley (Petroselinum crispum) germplasm diversity from the Greek Gene Bank using morphological, molecular and metabolic markers

Parsley (Petroselinum crispum) aromatic, edible leaves are used fresh or dried as a herb, but also for their pharmaceutical properties. Given the profound concern to high nutritious and pharmaceutical value of superior plant’s germplasm, a survey is presented in this study on the phenotypic, genetic and phytochemical characterization of fifteen Greek parsley landraces in comparison to nine commercial cultivars, all grown under the same conditions in Greece. Our data reported high differences between the Greek landraces and most of the commercial cultivars in a majority of morphological traits investigated according to the International Union for the Protection of New Varieties of Plants descriptors list. The genetic diversity of all landraces and commercial cultivars were investigated using Inter Simple Sequence Repeat and Amplified Fragment Length Polymorphism molecular markers. The percentage of polymorphic loci was 63.83 % for the cultivars, and all loci were polymorphic (100 %) for the Greek landraces, while considerably higher values of unbiased haploid gene diversity were revealed in the landraces compared with the commercial cultivars. The essential oil yield of the landraces and cultivars of parsley studied ranged from 0.11−0.26 mL 100 g−1 leaf FW. The major compounds in the parsley essential oils as determined by gas-chromatography were α-pinene (0.6–11.8%), β-pinene (0.2–8.2%), myrcene (1.3–13.5%), β-phellandrene (9.6–39.1 %), terpinolene (1.4–8.9 %), 1, 3, 8-p-menthatriene (0.1–43.4 %), cis-carveol (0.2–8.1 %), iso-dihydro carveol acetate (0.2–6.9 %), myristicin (0.51–44.4%) and apiole (0.01–35.2 %). According to the targeted liquid chromatographic analysis coumarin derivatives, hydrocinnamic acids, flavanones, flavones and flavonols were identified in parsley methanolic extracts. Flavones were represented by apigenin and luteolin derivatives, and flavonols by kaempferol, quercetin, galangin and morin. Apiin was the major flavone in all parsley samples ranging from 1732.57 to 3676.43 mg 100 g -1 dry weight.The wide variation in phenotypic, genetic and phytochemical profiles observed for the landraces, indicate that the Greek germplasm collection could serve as an important source of genetic material for plant breeding and selection towards the development of new cultivars with superior traits regarding their aroma quality and polyphenolic content but also to support ongoing studies on flavonoid biosynthesis in this culinary herb.

Flavone-Rich Fractions and Extracts from Oroxylum indicum and Their Antibacterial Activities against Clinically Isolated Zoonotic Bacteria and Free Radical Scavenging Effects.

Oroxylum indicum extracts from the seeds collected from Lampang and Pattani provinces in Thailand, and young fruits and flowers exhibited in vitro display antioxidant and antibacterial activities against clinically isolated zoonotic bacteria including Staphylococcus intermedius, Streptococcus suis, Pseudomonas aeruginosa, β-hemolytic Escherichia coli and Staphylococcus aureus. The orange crystals and yellow precipitates were obtained from the preparation processes of the seed extracts. The orange-red crystals from the seeds collected from Lampang province exhibited strong in vitro 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging effects (EC50 value = 25.99 ± 3.30 μg/mL) and antibacterial effects on S. intermedius and β-hemolytic E. coli while the yellow precipitate from the same source exhibited only antioxidant activity. Quantitative analysis of phytochemicals in O. indicum samples by spectrophotometric and HPLC techniques showed that they contained different amounts of total phenolic, total flavonoid and three major flavones; baicalin, baicalein and chrysin contents. Young fruit extract, which contained low amounts of flavone contents, still promoted antibacterial effects against the tested bacteria with IC50 values lower than 1 mg/mL and MIC values between 4 to 10 mg/mL in S. intermedius, S. aureus and S suis while higher IC50 and MIC values against P. aeruginosa and β-hemolytic E. coli were found. From scanning electron microscopy, the extract of the young fruit of O. indicum promoted morphological changes in the bacterial cells by disrupting the bacterial cell walls, inducing leakage of the cellular content, and generating the abnormal accumulation of cells. The mechanism of action of the extract for this antibacterial effect may be the disruption of the cell membrane and abnormal cell aggregations. Regression analysis of the results suggests the correlation between total phenolic and total flavonoid contents and antioxidant and antibacterial effects. Baicalin was found to have a high correlation with an inhibitory effect against β-hemolytic E. coli while three unidentified peaks, which could be flavones, showed high correlations with an inhibitory effect against S. intermedius, S. suis, P. aeruginosa and S. aureus.

Anti-glaucoma potential of hesperidin in experimental glaucoma induced rats

Glaucoma is well-known clinical eye conditions that damage the optic nerve due to abnormal pressure conditions in eye. Hesperidin is well-known glycoside widely present in the citrus fruits, and its aglycone form is known as hesperetin. Hesperidin is major flavone found in orange fruits. Hypotensive effect of hesperidin in acute and chronic glaucoma rats, glutamate level in vitreous humour and glutathione (GSH) level in aqueous humour were determined following 25, 50 and 100 mg/kg of hesperidin treatment. Acetazolamide (5 mg/kg) was used as positive control. Hesperidin treatment significantly reduced the increased intraocular pressure (IOP) level in dextrose induced ocular hypertension than saline treated rats. The effect of hesperidin was comparable to the positive control acetazolamide. Similarly, hesperidin treatment significantly reduced the IOP level in prednisolone acetate induced ocular hypertension than saline treated rats. In the aqueous humour, hesperidin treatment increased the glutathione level 125%, 184.4% and 231.2% at 25, 50 and 100 mg/kg of hesperidin respectively. In the vitreous humour, hesperidin treatment reduced the glutamate level 9.9%, 13.2% and 25.3% at 25, 50 and 100 mg/kg of hesperidin respectively. Histopathological analysis of normal saline treated rats showed morphological alteration in ciliary bodies. However, rats treated with hesperidin showed the reduced level of morphological alteration in ciliary bodies. Taking all these data together, it is suggested that the hesperidin supplementation was effective against glaucoma in experimental rats.