Showing papers on "Galangin published in 2012"

Mutagenicity of flavonoids assayed by bacterial reverse mutation (Ames) test.

Abstract: The mutagenicity of ten flavonoids was assayed by the Ames test, in Salmonella typhimurium strains TA98, TA100 and TA102, with the aim of establishing hydroxylation pattern-mutagenicity relationship profiles. The compounds assessed were: quercetin, kaempferol, luteolin, fisetin, chrysin, galangin, flavone, 3-hydroxyflavone, 5-hydroxyflavone and 7-hydroxyflavone. In the Ames assay, quercetin acted directly and its mutagenicity increased with metabolic activation. In the presence of S9 mix, kaempferol and galangin were mutagenic in the TA98 strain and kaempferol showed signs of mutagenicity in the other strains. The absence of hydroxyl groups, as in flavone, only signs of mutagenicity were shown in strain TA102, after metabolization and, among monohydroxylated flavones (3-hydroxyflavone, 5-hydroxyflavone and 7-hydroxyflavone), the presence of hydroxyl groups only resulted in minor changes. Luteolin and fisetin also showed signs of mutagenicity in strain TA102. Finally, chrysin, which has only two hydroxy groups, at the 5-OH and 7-OH positions, also did not induce mutagenic activity in any of the bacterial strains used, under either activation condition. All the flavonoids were tested at concentrations varying from 2.6 to 30.7 nmol/plate for galangin and 12.1 to 225.0 nmol/plate for other flavonoids. In light of the above, it is necessary to clarify the conditions and the mechanisms that mediate the biological effects of flavonoids before treating them as therapeutical agents, since some compounds can be biotransformed into more genotoxic products; as is the case for galangin, kaempferol and quercetin.

1H-NMR Simultaneous Identification of Health-Relevant Compounds in Propolis Extracts

Abstract: Introduction Propolis is a resinous substance collected by bees from exudates of different plants that is rich in well-known health-relevant phenolic compounds such as flavonoids and phenolic acids. Propolis extracts are very complex matrices difficult to study. Different analytical methods are usable to analyse propolis extracts and to obtain chemical fingerprint but to our knowledge NMR has not previously been used for this purpose. Objective This study aims to demonstrate that it is possible to use 1H-NMR for the simultaneous recognition of phenolic compounds in complex matrices, such as propolis extracts, using appropriate tools for spectra pre-treatment and analysis. Methodology In this work 12 typical phenolic propolis compounds (apigenin, chrysin, galangin, kaempferol, quercetin, naringenin, pinocembrin, pinostrobin, caffeic acid, cinnamic acid, p-coumaric acid and ferulic acid) were considered as reference compounds and their presence in samples was verified by HPLC-MS. A simple 1H-NMR sequence was used to obtain spectra of samples. Spectra were pre-treated by using an appropriate tool for spectra alignment and analysed by using software for the study of spectra originated from complex matrices. Sixty-five propolis samples were used to test the proposed identification procedure. Results Ten out of 12 considered compounds were identified as statistically significant in most of the samples. Conclusion This work suggests that it is possible to efficiently use 1H-NMR, coupled with appropriate spectral analytical tools, for the simultaneous detection of phenolic compounds in complex matrices. Copyright © 2011 John Wiley & Sons, Ltd.

Identification and Quantification of Phytochemical Composition and Anti-inflammatory and Radical Scavenging Properties of Methanolic Extracts of Chinese Propolis

Abstract: Fifteen propolis samples collected from different regions of China were investigated and compared for their phytochemical composition and anti-inflammatory and radical scavenging properties. Eleven compounds including caffeic, p-coumaric, ferulic, isoferulic, and 3,4-dimethylcaffeic acids, pinobanksin, chrysin, pinocembrin, galangin, pinobanksin 3-acetate, and caffeic acid phenylethyl ester were quantified for the 15 propolis samples using a UHPLC method, whereas 38 compounds were identified by UPLC/Q-TOF-MS. The 15 propolis samples significantly differed in their total phenolic and total flavonoid contents, as well as their phytochemical profiles. The methanol extracts of propolis also showed significant anti-inflammatory effects in LPS-stimulated RAW 264.7 mouse macrophage cells at 10 μg propolis extract/mL concentration. Additionally, the propolis samples differed in their DPPH, ABTS cation, hydroxyl, and peroxide radical scavenging capacities and ferric reducing abilities. The results from this study may be used to improve the commercial production and consumption of Chinese propolis products.

Synergistic activity and mode of action of flavonoids isolated from smaller galangal and amoxicillin combinations against amoxicillin-resistant Escherichia coli.

Abstract: Aim: The smaller galangal is extracted, purified and identified the bioactive compounds. The purpose of this research was to investigate whether these isolated compounds have antibacterial and synergistic activity against amoxicillin-resistant Escherichia coli (AREC) when used singly and in combination with amoxicillin. The primarily mode of action is also studied. Method and Results: The galangin, kaempferide and kaempferide-3-O-β-d-glucoside were isolated. The minimum inhibitory concentrations(MIC) of amoxicillin and these flavonoids against AREC were between 500 and >1000 μg ml−1. Synergistic activity was observed on combining amoxicillin with these flavonoids. The combinations of amoxicillin and these flavonoids exhibited a synergistic effect, reducing AREC cell numbers. Electron microscopy showed that these combinations damaged the ultrastructure of AREC cells. The results indicated that these combinations altered outer membrane permeability but not affecting cytoplasmic membrane. Enzyme assays showed that these flavonoids had an inhibitory activity against penicillinase. Conclusion: These results indicated that these flavonoids have the potential to reverse bacterial resistance to amoxicillin in AREC and may operate via three mechanisms: inhibition of peptidoglycan and ribosome synthesis, alteration of outer membrane permeability, and interaction with β-lactamases. Significance and Impact of the Study: These findings offer the potential to develop a new generation of phytopharmaceuticals to treat AREC.

Galangin induces autophagy through upregulation of p53 in HepG2 cells.

Abstract: Aim: To investigate the mechanism by which galangin, a polyphenolic compound derived from medicinal herbs, induces autophagy of HepG2 cells. Methods: The MTT [3-(4,5-dimethyl-thiazol-2-yl)2,5-diphenyl-tetrazolium bromide] assay was used to measure cell viability. Apoptosis was evaluated by TUNEL assay with flow cytometry, and PARP cleavage was detected by Western blotting. Autophagy was measured by fluorescence microscopy and transmission electron microscopy. Protein expressions were detected by Western blotting. Pifithrin-α was used for pretreatment and siRNA was used to knock down p53 expression to explore the pathway mediated by galangin in HepG2 cells. Furthermore, Hep3B cells were used to express the exogenous wild-type p53. Results: Galangin treatment inhibited cell proliferation and induced autophagy (130 µmol/l) and apoptosis (370 µmol/l). In particular, galangin treatment in HepG2 cells caused (1) an accumulation of autophagosomes, (2) elevated levels of microtubule-associated protein light chain 3, and (3) an increased percentage of cells with vacuoles. p53 expression was also increased. The galangin-induced autophagy was attenuated by the inhibition of p53 in HepG2 cells, and overexpression of p53 in Hep3B cells restored the galangin-induced higher percentage of cells with vacuoles to normal level. Conclusion: Our results indicate that galangin not only induced apoptosis but also prompted cell autophagy in different concentrations. Galangin mediates autophagy through a p53-dependent pathway in HepG2 cells. Our findings may help in the discovery of a chemotherapeutic drug with the novel pattern of inhibiting cell proliferation for the treatment of hepatocellular carcinoma cells.

Pharmacological and bioanalytical aspects of galangin-a concise report

Abstract: Flavonoids are low molecular weight plant phytoconstituents, widely distributed in the leaves, seeds, bark and flowers of plants. It has various pharmacological activities and protects plants against ultraviolet radiation, pathogens, and herbivores. Most of the beneficial health effects of flavonoids are mainly due to its antioxidant properties. Galangin is a flavonol found in honey, Alpinia officinarum, Helichrysum aureonitens and in propolis. It showed anti-mutagenic, anti-clastogenic, anti-oxidative, radical scavenging, metabolic enzyme modulating activity and effective against certain types of cancers. The present review described the pharmacological activity and bioanalytical aspects of galangin, which may be benificial to the researchers who wants to explore the hidden potential of galangin.

Induction of oxidative DNA damage by flavonoids of propolis: its mechanism and implication about antioxidant capacity.

Abstract: Propolis from beehives is commonly used as a home remedy for various purposes including as a topical antiseptic. Despite its antioxidant capacity, propolis induces oxidative DNA damage. In exploring the underlying mechanism, we found that the induction of oxidative DNA damage is attributed to the hydrogen peroxide (H(2)O(2)) produced by propolis. The formation of H(2)O(2) can take place without the participation of cells but requires the presence of transition metal ions such as iron. Flavonoids such as galangin, chrysin, and pinocembrin that are commonly detected in propolis have the capacity to induce oxidative DNA damage, and that capacity correlates with the production of H(2)O(2), suggesting the involvement of flavonoids in propolis in this process. On the basis of these results, we propose that the flavonoids of propolis serve as temporary carriers of electrons received from transition metal ions that are relayed to oxygen molecules to subsequently generate superoxide and H(2)O(2). In addition, propolis induces oxidative DNA damage that is subject to repair, and propolis-treated cells show a lower level of DNA damage level when challenged with another oxidative agent such as amoxicillin. This is reminiscent of an adaptive response that might contribute to the beneficial effects of propolis.

Alpinia officinarum inhibits adipocyte differentiation and high-fat diet-induced obesity in mice through regulation of adipogenesis and lipogenesis.

Abstract: Although Alpinia officinarum has been used in traditional medicine for the treatment of several conditions, such as abdominal pain, emesis, diarrhea, impaired renal function, and dysentery, little is known about its function in obesity. In this study, we investigated the antiobesity effect of A. officinarum ethanol extract (AOE) on lipid accumulation in 3T3-L1 cells and obesity in mice fed a high-fat diet (HFD). AOE dose-dependently suppressed lipid accumulation during differentiation of 3T3-L1 preadipocytes by downregulating CCAAT enhancer binding protein α (C/EBPα), sterol regulatory element binding protein-1 (SREBP-1), and peroxisome proliferator-activated receptor-γ (PPAR-γ) genes. Galangin, a major component of A. officinarum, had antiadipogenic effects in 3T3-L1 cells. AOE supplementation in mice fed a HFD revealed that AOE significantly decreased HFD-induced increases in body, liver, and white adipose tissue weights and decreased serum insulin and leptin levels. To elucidate the inhibitory...

By improving regional cortical blood flow, attenuating mitochondrial dysfunction and sequential apoptosis galangin acts as a potential neuroprotective agent after acute ischemic stroke.

Abstract: Ischemic stroke is a devastating disease with a complex pathophysiology. Galangin is a natural flavonoid isolated from the rhizome of Alpina officinarum Hance, which has been widely used as an antioxidant agent. However, its effects against ischemic stroke have not been reported and its related neuroprotective mechanism has not really been explored. In this study, neurological behavior, cerebral infarct volumes and the improvement of the regional cortical blood flow (rCBF) were used to evaluate the therapeutic effect of galangin in rats impaired by middle cerebral artery occlusion (MCAO)-induced focal cerebral ischemia. Furthermore, the determination of mitochondrial function and Western blot of apoptosis-related proteins were performed to interpret the neuroprotective mechanism of galangin. The results showed that galangin alleviated the neurologic impairments, reduced cerebral infarct at 24 h after MCAO and exerted a protective effect on the mitochondria with decreased production of mitochondrial reactive oxygen species (ROS). These effects were consistent with improvements in the membrane potential level (Dym), membrane fluidity, and degree of mitochondrial swelling in a dose-dependent manner. Moreover, galangin significantly improved the reduced rCBF after MCAO. Western blot analysis revealed that galangin also inhibited apoptosis in a dose-dependent manner concomitant with the up-regulation of Bcl-2 expression, down-regulation of Bax expression and the Bax/Bcl-2 ratio, a reduction in cytochrome c release from the mitochondria to the cytosol, the reduced expression of activated caspase-3 and the cleavage of poly(ADP-ribose) polymerase (PARP). All these data in this study demonstrated that galangin might have therapeutic potential for ischemic stroke and play its protective role through the improvement in rCBF, mitochondrial protection and inhibiting caspase-dependent mitochondrial cell death pathway for the first time.

Design of potent inhibitors of acetylcholinesterase using morin as the starting compound

Abstract: Inhibition of acetylcholinesterase (AChE) is a promising treatment strategy for Alzheimer's disease (AD). Oxidative stress, inflammation and accumulation of metal ions at sites of neurodegeneration have been observed in association with AD. Flavonoids are well known for their action against inflammation and oxidative stress. Hence, they can be used for treating diseases such as AD, cancer, atherosclerosis and Parkinson's disease. Flavonols such as quercetin, myricetin, galangin, fisetin and kaempferol have been reported as inhibitors of AChE. In the present work, the enzyme inhibitory properties of morin, a flavonol, has been tested against AChE. The binding pattern of morin and 12 other flavonols at the active site of human AChE has been analyzed using molecular modeling and docking methods. In order to enhance the binding affinity of AChE for morin, in silico structural modification of the compound was carried out. The structural elements responsible for its biological functions were retained during the...

Characterization of flavonol inhibition of DnaB helicase: real-time monitoring, structural modeling, and proposed mechanism.

Abstract: DnaB helicases are motor proteins essential for DNA replication, repair, and recombination and may be a promising target for developing new drugs for antibiotic-resistant bacteria. Previously, we established that flavonols significantly decreased the binding ability of Klebsiella pneumoniae DnaB helicase (KpDnaB) to dNTP. Here, we further investigated the effect of flavonols on the inhibition of the ssDNA binding, ATPase activity, and dsDNA-unwinding activity of KpDnaB. The ssDNA-stimulated ATPase activity of KpDnaB was decreased to 59%, 75%, 65%, and 57%, in the presence of myricetin, quercetin, kaempferol, and galangin, respectively. The ssDNA-binding activity of KpDnaB was only slightly decreased by flavonols. We used a continuous fluorescence assay, based on fluorescence resonance energy transfer (FRET), for real-time monitoring of KpDnaB helicase activity in the absence and presence of flavonols. Using this assay, the flavonol-mediated inhibition of the dsDNA-unwinding activity of KpDnaB was observed. Modeled structures of bound and unbound DNA showed flavonols binding to KpDnaB with distinct poses. In addition, these structural models indicated that L214 is a key residue in binding any flavonol. On the basis of these results, we proposed mechanisms for flavonol inhibition of DNA helicase. The resulting information may be useful in designing compounds that target K. pneumoniae and other bacterial DnaB helicases.

Inhibitory activity of liposomal flavonoids during oxidative metabolism of human neutrophils upon stimulation with immune complexes and phorbol ester

Abstract: Context and objective: The massive production of reactive oxygen species by neutrophils during inflammation may cause damage to tissues. Flavonoids act as antioxidants and have anti-inflammatory effects. In this study, liposomes loaded with these compounds were evaluated as potential antioxidant carriers, in attempt to overcome their poor solubility and stability. Materials and methods: Liposomes containing quercetin, myricetin, kaempferol or galangin were prepared by the ethanol injection method and analyzed as inhibitors of immune complex (IC) and phorbol ester-stimulated neutrophil oxidative metabolism by luminol (CLlum) and lucigenin-enhanced (CLluc) chemiluminescence (CL) assays. The mechanisms involved this activity of liposomal flavonoids, such as cytotoxicity and superoxide anion scavenging capacity, and their effect on phagocytosis of ICs were also investigated. Results and discussion: The results showed that the inhibitory effect of liposomal flavonoids on CLlum and CLluc is inversely related to...

Anticomplement and Antimicrobial Activities of Flavonoids from Entada phaseoloides

Abstract: Seventeen flavonoids isolated from the extracts of the stem of Entada phaseoloides were investigated for their anticomplement (both classic and alternative pathways) and antimicrobial activities against Gram-positive bacteria (MRSA, MSSA, Standard Enterococcus and Bacillus subtilis), Gram-negative bacteria (Escherichia coli, Pseudomonas aeuroginosa) and the yeast-like pathogenic fungus Candida albicans. The anticomplement studies revealed a dose-dependent activity among isolated quercetin, luteolin, apigenin, galangin, 5,2',5'-trihydroxy-3,7,4'-trimethoxyflavone-2'-O-beta-D-glucoside (+)-3,3',5',5,7-pentahydroflavanone, (+)-dihydrokaempferol, (-)-epicatechin, (+)-catechin, naringenin, and 5,7,3',5'-tetrahydroxyflavanone, and the antimicrobial results indicated that quercetin, 5,7,4'-trihydroxy-3'-methoxyflavonol and galangin produced the inhibitory activities against MRSA, MSSA, and Standard Enterococcus, while luteolin and rhamnocitrin displayed inhibition against only MRSA and MSSA. To the best of our knowledge, this is the first report that describes the anticomplement and antimicrobial activities of the stem of E. phaseoloides.

Investigation of Sensitivity Against Different Flavonoid Derivatives of Aminophenyl-Modified Glassy Carbon Sensor Electrode and Antioxidant Activities

Abstract: The electrochemical behaviors of 10 structurally different flavonoids (quercetin, galangin, chrysin, 3-hydroxyflavone, naringenin, luteolin, apigenin, flavone, kaempferol, and naringin) on a glassy carbon electrode were studied by cyclic voltammetry. In the current study, nitrophenyl diazonium salt has been synthesized from p-nitrophenylamine. One millimolar prepared nitrophenyl diazonium salt (in 100 mM tetrabutylammonium tetrafluoroborate) in acetonitrile was used to modify the glassy carbon electrode. Nitro groups have been reduced to amine groups in 100 mM HCl medium on the nitrophenyl-modified glassy carbon electrode surface. Although nitrophenyl-modified glassy carbon electrode surface was electro-inactive, it is activated by reducing the nitro group into amine group. And then, aminophenyl-modified glassy carbon electrode surface has been used for the determination of antioxidant activities of 10 flavonoid derivatives with cyclic voltammetry technique. The activity sequence of the investigated, structurally different, flavonoids follows the sequence: quercetin > galangin > chrysin > 3-hydroxyflavone > naringenin > luteolin > apigenin > flavone > kaempferol > naringin.

The Bioflavonoid Galangin Suppresses the Growth of Ehrlich Ascites Carcinoma in Swiss Albino Mice: A Molecular Insight

Abstract: Bioflavonoids are plant compounds touted for their potential to treat or prevent several diseases including cancer caused by various stress conditions. Galangin (4H-1-Benzopyran-4-one, 3, 5, 7-trihydroxy-2-phenyl-), a flavonoid, is a polyphenolic compound found primarily in medicinal herb, Alpinia galanga. This study aims to demonstrate the galangin as a pharmacological lead compound using in vitro, in vivo, and in silico model targeting specific cancer condition and proteins. The proliferation of MCF-7 and Ehrlich ascites carcinoma (EAC) cells was significantly inhibited with an IC50 of 34.11 and 22.29 μg/ml, respectively. In an animal model system, galangin has inhibited the tumor growth by 73.51% ± 4.742 in EAC-induced Swiss Albino mice with no evidences of mortality as compared to standard drug, 5-fluorouracil. The effectiveness of galangin is proven in an animal system suggesting its pharmacokinetics behavior in an animal model which is also complemented by outcome of in silico analysis with more than 88 % of human intestinal absorption and significant Caco-2 cell, MDCK cell, and skin permeability as predicted by in silico methods. Galangin was docked against 19 different proteins involved in tumorogenesis and apoptosis; the energetic analysis indicates that it exhibits higher predicted binding free energy of −12.7 kcal/mol with Bcl-xL protein.

Flavonoids in propolis acting on mast cell-mediated wound healing

Abstract: Barroso et al. have shown, on the latest issue of Inflammopharmacology, that the topical application of propolis on surgical wounds affected the number of mast cells recruited in these sites, and suggested two well-known antiinflammatory components present in propolis, namely caffeic acid and artepillin C, as possible active molecules (Borrelli et al. 2002; Paulino et al. 2008). It is widely acknowledged that propolis down-regulates type I allergy and inflammation by affecting mast cells, but the effective components of propolis, which cause these effects, remain still unknown. Propolis components vary depending on the area from which they are collected, mainly because of the genetic variability among wild plants in different geographic regions: variability in phenolics composition may result in different biochemical property of the propolis, depending on the main component active in raw propolis or in its extracts. In Chinese propolis, chrysin, kaempferol and its derivative, pinocembrin and galangin were identified as the main flavonoids able to act on mast cell-mediated inflammatory response, while chrysin was shown to inhibit IL-4 and MCP-1 production from antigen-stimulated RBL2H3 basophil/mast cell lines (Nakamura et al. 2010). On the other hand, Brazilian propolis extract contains only small amounts of these flavonoids, which might suggest that variation in propolis components could affect antiallergic and anti-inflammatory properties (Nakamura et al. 2010). Brazilian propolis contains, therefore, major percentage of phenolic acids, such as caffeic acid phenethyl ester (CAPE) and artepillin C (Park et al. 2002). As the activity of propolis, like many natural products, may be due to the synergic effect of several bioactive components, it will be necessary to distinguish between different types of propolis and analyse its complex compositions to guarantee specific biological activities of propolis diffused worldwide (Frankland Sawaya et al. 2011). Furthermore, inflammation by mast cells can be inhibited by several flavonoids present in propolis. Recent evidence was reported showing that chrysin decreased gene expression of pro-inflammatory cytokines, such as TNF-a, IL-1b, IL-4 and IL-6 in mast cells by a nuclear factor-jB (NF-jB) and caspase-1 dependent mechanism (Bae et al. 2011). Genistein modulates NF-jB and TNF-a expression during the early stage of wound healing (Park et al. 2011). CAPE accelerates cutaneous wound healing and it is arguable that propolis with a significant amount of this phenolic acid may exert a wound repairing property (Serarslan et al. 2007). The antiinflammatory property attributed to flavonoids in propolis might suggest that these polyphenols should exert their action toward other newly discovered function of mast cells (Ng 2010), even in association with CAPE or other phenolic acids. Wound healing is a complex process of lysis and reconstitution controlled by a series of cell signaling proteins and involved tissue regeneration and angiogenesis (Hiromatsu and Toda 2003; Nienartowicz et al. 2006). Mast cells have been shown to play a significant role in the early inflammatory stage of wound healing and also influence proliferation and tissue remodeling in skin; according to some authors in wound healing, mast cells are able to modulate only the inflammatory but not the proliferative response in healing and reconstituting damaged tissue (Egozi et al. 2003), while other reports showed that mast cells are involved in tissue remodeling in the late phase of wound healing (Iba et al. 2004), thus expanding S. Chirumbolo (&) Unit of Geriatry, Department of Medicine, University Laboratory of Medical Research, University of Verona, Policlinico GB Rossi piazzale AL Scuro 10, 37134 Verona, Italy e-mail: salvatore.chirumbolo@univr.it Inflammopharmacol (2012) 20:99–101 DOI 10.1007/s10787-012-0125-9 Inflammopharmacology

Influence of dietary flavonoids on the glycation of plasma proteins.

Abstract: It has been suggested that the increasing glycation in diabetes can influence the ability of plasma proteins to bind to small molecules. Herein, the influence of flavonoids on the glycation of plasma proteins was investigated. After being incubated with glucose at 37 °C, the levels of glycated albumin (HGA) were significantly improved in healthy human plasma proteins (HPP). The inhibitory effects of flavonoids against the formation of advanced glycation products (AGEs) in HPP were determined as: galangin > apigenin > kaempferol ≈ luteolin > myricetin > quercetin. After being combined with 20 μmol L−1 of quercetin for 11 days, the fresh plasma with δ-glucose caused 323.05–32.07% inhibition of HGA formation in type II diabetes plasma proteins (TPP). Luteolin showed weak inhibition of HGA formation in TPP. However, kaempferol, galangin and apigenin hardly inhibited the formation of HGA in TPP. These results showed that more hydroxyl groups on ring B of flavonoids will enhance the inhibitory effects on the HGA formation in TPP.

Physical Properties and Chemical Analysis of Iraqi Propolis

Abstract: Propolis is a complex resinous substance manufactured by honeybees (Apis mellifera L.) to mainly protect the hive against pathogens. Physical properties of Iraqi propolis from eight regions (Al-Sulaymania, Erbil, Dohuk, Nineveh, Kirkuk, Salah Al-Din, Diyala and Al-Anbar) were investigated. Chemical analysis was achieved by thin layer chromatography (TLC) technique using five of different mobile phases including Toluene: ethyl acetate: formic acid; Toluene: ethyl acetate: acetic acid; n-hexane: ethyl acetate: acetic acid; Petroleum ether: ethyl acetate: formic acid and n-hexane: ethyl acetate: formic acid. Functional groups of separated chemical compounds were detected by IR spectroscopy. Results revealed variations in color and texture of Iraqi propolis, while odor was ranged between midly aromatic to high aromatic resinous according to geographical origin. Chemical analysis showed availability of ten important bioactive compounds in Iraqi propolis: Flavanone, 3Hydroxyflavone, Chrysin, Quercetin, Galangin, Apigenin, Kaempferol, O-coumaric acid, Caffeic acid and Ferulic acid.

Study of the interaction of galangin, kaempferol and quercetin with BSA

Abstract: −− The interactions between Bovine Serum Albumin (BSA) and three flavonols, galangin, kaempferol and quercetin were studied by means of fluorescence spectroscopy. The fluorescence intensity of BSA exhibits remarkable decrease along with appreciable blue-shift of its maximum emission wavelength upon addition of the three compounds, respectively. The respective binding constant Kα and number of binding sites of each compound were calculated, and the quenching mechanism was proposed. Based on the values of thermodynamic parameters, the binding of each compound proceeds spontaneously with BSA. The binding distance between each and BSA was obtained by Foerster's dipole-dipole non-radiation energy transfer mechanism. Keywords−− Galangin, Kaempferol, Quercetin, flavonols, Bovine Serum Albumin, Fluorescence Spectroscopy.

In Search of New Biological Activities of Isolates from Odontoglossum Harvengtense ‘Tutu’

Abstract: Background In the current study, we isolated four known compounds, two phenanthrenes, 2,5-dihydroxy-4,9-dimethoxy phenanthrene [1] and 4-methoxyphenanthrene-2,7-diol (flavanthrinin) [2], one phenanthrenequinone, 5-hydroxy-2,3-dimethoxy-1,4-phenanthrenequinone [3], and one flavone, 3,5,7-trihydroxyflavone (galangin) [4], from the ethyl acetate (EtOAc) extract of Odontoglossum Harvengtense 'Tutu' through bioassay-guided fractionation, and investigated their biological activities. Materials and methods The isolated compounds were identified with spectroscopic analysis and through comparison to literature values. Cytotoxic activity towards human tumor and normal cells was determined by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) method. Nitric oxide (NO) was determined by the Griess method. Radical scavenging activity was determined by electron spin resonance (ESR) spectroscopy. Osteoclastogenesis was monitored by tartrate-resistant acid phosphatase (TRAP) activity. Results The compounds had slightly higher cytotoxicity towards human oral squamous cell carcinoma and leukemia cell lines as compared with human normal oral cells, yielding a tumor specificity value of 1.1-2.7. Among these four compounds, 1 most potently inhibited the lipopolysaccharide (LPS)-stimulated NO production and the receptor activator of nuclear factor-κB ligand (RANKL)-stimulated osteoclastogenesis by mouse macrophage-like RAW264.7 cells. Micromolar concentrations of 1 scavenged the NO radical produced from 1-hydroxy-2-oxo-3-(N-3-methyl-3-aminopropyl)-3-methyl-1-triazene. Conclusion The present study demonstrated, for the first time, that 1 inhibited both macrophage activation and osteoclast differentiation, suggesting its possible anti-inflammatory action.

Galangin Attenuates Cognitive Impairment in Senescent Mice

Abstract: Objective To investigate the effect of galangin(GL) on cognitive impairment in the senescent mice induced by D-galactose(D-gal).Methods D-gal was subcutaneously injected to establish a senescent mice model.The Morris water maze test and step-down avoidance one were performed to study the learning and memory abilities of mice.The activities of superoxide dismutase(SOD),glutathione peroxidase(GPx),catalase(CAT) and content of malondialdehyde(MDA) in mice hippocampus were detected by biochemical examination.Results The mice treated with D-gal generated significant cognitive deficiency.Administration of GL to D-gal treated mice ameliorated cognitive impairment in the hippocampus.Biochemical examination revealed that GL attenuated the decreased activities of SOD,GPx,CAT and reduced MDA levels in the hippocampus of D-gal-treated mice.Conclusion Galangin possesses anti-oxidative effect by improving the cognitive function,and increasing activities of SOD,GPx,CAT and lowering MDA of the senescent mice induced by D-gal.

Composition Analysis in Ethanol Extracts of Propolis Samples from Northern China

Abstract: The purpose of this study was to compare the contents of total phenols,total flavonoids and individual components in ethanol extracts of propolis samples collected from Northern China(Beijing and 10 provinces).The content of total flavonoids and total phenols were determined by NaNO2-Al(NO3)3 method and Folin-Ciocalteau method,respectively.Quantitative and qualitative HPLC analysis of phenols in propolis extracts was carried out by comparison with standard references for geographic cluster analysis of propolis samples.The results showed that the contents of total flavonoids and total phenols of propolis samples varied with geographic origin.The highest contents of caffeic acid,kaempferol,pinocembrin,chrysin,galangin and benzyl cinnamate were found in propolis samples from Henan province;propolis samples from Liaoning province were the richest in apigenin and isorhamnetin;propolis samples from Shandong province showed the highest content of rhamnetin.

Application of galangal extract in preparation of medicine for inhibiting calcium channel

Abstract: The invention aims to extend application of a galangal extract which contains galangin and is used to inhibit the calcium channel, in particular TRP (Transient ReceptorPotential) channel, so as to prevent and treat heart cerebrovascular diseases such as atherosclerosis and the like The TRP channel is a non-selective cation channel and has a close relation with heart cerebrovascular diseases suchas atherosclerosis and the like By inhibiting the activity of TRPC channel of vascular endothelial cells, the vascular function can be improved obviously and the vascular pathological changes of atherosclerosis can be improved obviously too Chemical protection, antioxidation, antiviral and antibacterial action, anti-cancer effect of galangin are further explored previously and the invention extends the use of the galangal extract to prepare medicine for preventing and treating heart cerebrovascular diseases