Inhibition of gastric H(+),K(+)-ATPase and Helicobacter pylori growth by phenolic antioxidants of Curcuma amada

Gastric ulcer is the most prevalent gastrointestinal disorder, resulting from oxidative stress, Helicobacter pylori infection, up-regulation of proton potassium ATPase (PPA) activity, down-regulation of gastric mucosal defense, etc. In this paper it is reported that phenolic fractions of Curcuma amada, commonly known as mango ginger, acted as potent inhibitors of PPA and H. pylori growth. Mango ginger free phenolics (MGFP) and mango ginger bound phenolics (MGBP) inhibited PPA at IC50 values of 2.2 +/- 0.21 and 0.7 +/- 0.08 microg/mL, respectively, exhibiting 9-27-fold better potency over lansoprazole (IC(50) of 19.3 +/- 2.2 microg/mL). MGFP is constituted by caffeic (26%), gentisic (24%), ferulic (20%), gallic (10%), cinnamic (7%), and protocatechuic acids (7%) and MGBP by ferulic (47%), cinnamic (29%), p-coumaric acid (11%), and syringic (5%) acids as major phenolic acids. MGFP and MGBP further exhibited free radical scavenging (IC(50) of 2.2 +/- 0.17 and 4.2 +/- 0.36 microg/mL), reducing power abilities (193-104 units/g), inhibition of lipid peroxidation (IC(50) of 10.3 +/- 0.91 and 15.6 +/- 1.6 microg/mL), and DNA protection (80% at 4 microg), indicating strong antioxidative properties. MGFP and MGBP thus may be potential and inexpensive multistep blockers against ulcers.     

Impact of isolation method on the antioxidant activity of rapeseed meal phenolics

Rapeseed meal is the byproduct of the rapeseed deoiling process. Among oilseed plants, rapeseed contains the greatest amount of phenolic compounds. In this study, the rapeseed phenolics were isolated with aqueous methanol, aqueous ethanol, hot water, and enzymatically with ferulic acid esterase. These isolates were tested for radical scavenging and for liposome and low-density lipoprotein (LDL) model systems. The radical scavenging activities of all isolates were >60% at a concentration of 1.5 mg/mL. In the liposome model system the formation of hexanal was inhibited by all rapeseed meal isolates by >90% and the formation of conjugated diene hydroperoxides by >80% (8.4 microg/mL concentration). All rapeseed meal isolates also inhibited oxidation of LDL particles by >90% inhibition (4.2 microg/mL concentration). Isolation of rapeseed meal phenolics with either water or enzyme is a very suitable method devoid of organic solvents. Thus, rapeseed meal phenolics constitute an interesting source for food and cosmetic applications with antioxidant effect.     

Tumor cell proliferation and cyclooxygenase inhibitory constituents in horseradish (Armoracia rusticana) and Wasabi (Wasabia japonica)

Cyclooxygenase and human tumor cell growth inhibitory extracts of horseradish (Armoracia rusticana) and wasabi (Wasabia japonica) rhizomes upon purification yielded active compounds 1-3 from horseradish and 4 and 5 from wasabi rhizomes. Spectroscopic analyses confirmed the identities of these active compounds as plastoquinone-9 (1), 6-O-acyl-beta-d-glucosyl-beta-sitosterol (2), 1,2-dilinolenoyl-3-galactosylglycerol (3), linolenoyloleoyl-3-beta-galactosylglycerol (4), and 1,2-dipalmitoyl-3-beta-galactosylglycerol (5). 3-Acyl-sitosterols, sinigrin, gluconasturtiin, and phosphatidylcholines isolated from horseradish and alpha-tocopherol and ubiquinone-10 from wasabi rhizomes isolated were inactive in our assays. At a concentration of 60 microg/mL, compounds 1 and 2 selectively inhibited COX-1 enzyme by 28 and 32%, respectively. Compounds 3, 4, and 5 gave 75, 42, and 47% inhibition of COX-1 enzyme, respectively, at a concentration of 250 microg/mL. In a dose response study, compound 3 inhibited the proliferation of colon cancer cells (HCT-116) by 21.9, 42.9, 51.2, and 68.4% and lung cancer cells (NCI-H460) by 30, 39, 44, and 71% at concentrations of 7.5, 15, 30, and 60 microg/mL, respectively. At a concentration of 60 microg/mL, compound 4 inhibited the growth of colon, lung, and stomach cancer cells by 28, 17, and 44%, respectively. This is the first report of the COX-1 enzyme and cancer cell growth inhibitory monogalactosyl diacylglycerides from wasabi and horseradish rhizomes.     

Antioxidant properties of ferulic acid and its related compounds

Antioxidant activity of 24 ferulic acid related compounds together with 6 gallic acid related compounds was evaluated using several different physical systems as well as their radical scavenging activity. The radical scavenging activity on 1,1-diphenyl-2-picrylhydrazyl (DPPH) decreased in the order caffeic acid > sinapic acid > ferulic acid > ferulic acid esters > p-coumaric acid. In bulk methyl linoleate, test hydroxycinnamic acids and ferulic acid esters showed antioxidant activity in parallel with their radical scavenging activity. In an ethanol-buffer solution of linoleic acid, the activity of test compounds was not always associated with their radical scavenging activity. Ferulic acid was most effective among the tested phenolic acids. Esterification of ferulic acid resulted in increasing activity. The activity of alkyl ferulates was somewhat influenced by the chain length of alcohol moiety. When the inhibitory effects of alkyl ferulates against oxidation of liposome induced by AAPH were tested, hexyl, octyl, and 2-ethyl-1-hexyl ferulates were more active than the other alkyl ferulates. Furthermore, lauryl gallate is most effective among the tested alkyl gallates. These results indicated that not only the radical scavenging activity of antioxidants, but also their affinity with lipid substrates, might be important factors in their activity.     

Insulin secretion and cyclooxygenase enzyme inhibition by cabernet sauvignon grape skin compounds

Bioassay-guided isolation and purification of hexane and ethyl acetate extracts of Cabernet Sauvignon grape skin yielded nine compounds (1-9), which were identified as beta-sitosterol-6'-linolenoyl-3-O-beta-D-glucopyranoside (1), beta-sitosterol (2), beta-sitosterol-3-O-beta-D-glucoside (3), oleanolic acid (4), oleanolic aldehyde (5), resveratrol (6), (+)-epsilon-viniferin (7), (-)-catechin (8), and 1-triacontanol (9). The structures of these compounds were established by spectroscopic methods. The compounds were assayed for insulin production using an INS-1 cell assay. In a dose-response study, compound 4 stimulated insulin production of INS-1 cells by 20.23, 87.97, 1.13, and 6.38 ng of insulin/mg of protein at 6.25, 12.5, 25, and 50 microg/mL, respectively. This trend was similar to the dose-dependent insulin production of INS-1 cells by glucose. Compound 5 also showed a dose-dependent insulin production in this assay. The isolated compounds were also assayed for cyclooxygenase-1 and -2 (COX) enzyme inhibitory activities. At 100 microg/mL, compounds 2, 3, and 4 inhibited the COX-2 enzyme by 11, 12, and 10%, respectively, but did not show activities on the COX-1 enzyme. Compounds 6, 7, and 8 at 100 microg/mL inhibited the COX-1 enzyme by 98, 99, and 98%, respectively, and the COX-2 enzyme by 0, 47, and 72%, respectively. This is the first report of beta-sitosterol-6'-linolenoyl-3-O-beta-D-glucopyranoside (1) from grape skin and insulin secretion activities of compounds 4 and 5.     

Free radical scavengers and antioxidants from Lemongrass (Cymbopogon citratus (DC.) Stapf.)

Methanol, MeOH/water extracts, infusion, and decoction of Cymbopogon citratus were assessed for free radical scavenging effects measured by the bleaching of the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical, scavenging of the superoxide anion, and inhibition of the enzyme xanthine oxidase (XO) and lipid peroxidation in human erythrocytes. The extracts presented effect in the DPPH and superoxide anion assay, with values ranging between 40 and 68% and 15-32% at 33 and 50 microg/mL, respectively, inhibited lipid peroxidation in erythrocytes by 19-71% at 500 microg/mL and were inactive toward the XO at 50 microg/mL. Isoorientin, isoscoparin, swertiajaponin, isoorientin 2' '-O-rhamnoside, orientin, chlorogenic acid, and caffeic acid were isolated and identified by spectroscopic methods. Isoorientin and orientin presented similar activities toward the DPPH (IC(50): 9-10 microM) and inhibited lipid peroxidation by 70% at 100 microg/mL. Caffeic and chlorogenic acid were active superoxide anion scavengers with IC(50) values of 68.8 and 54.2 microM, respectively, and a strong effect toward DPPH. Caffeic acid inhibited lipid peroxidation by 85% at 100 microg/mL.     

Tumor cell proliferation and cyclooxygenase enzyme inhibitory compounds in Amaranthus tricolor

Amaranthus tricolor is consumed as a vegetable in Asia. Bioassay-directed isolation of leaves and stems of A. tricolor yielded three galactosyl diacylglycerols (1-3) with potent cyclooxygenase and human tumor cell growth inhibitory activities. The purified compounds were characterized by spectroscopic methods. In addition, the fatty acid moieties in diacyl galactosyl glyerols were characterized by GC-MS analyses. The galactosyl diacylglycerols 1-3 inhibited the cyclooxygenase-1 (COX-1) enzyme by 78, 63, and 93% and the cyclooxygenase-2 (COX-2) enzyme by 87, 74, and 95%, respectively. These compounds were tested for antiproliferative activity using human AGS (gastric), CNS (central nervous system; SF-268), HCT-116 (colon), NCI-H460 (lung), and MCF-7 (breast) cancer cell lines. Compound 1 inhibited the growth of AGS, SF-268, HCT-116, NCI-H460, and MCF-7 tumor cell lines with IC50 values of 49.1, 71.8, 42.8, 62.5, and 39.2 mug/mL, respectively. For AGS, HCT-116, and MCF-7 tumor cell lines, the IC50 values of compounds 2 and 3 were 74.3, 71.3, and 58.7 microg/mL and 83.4, 73.1, and 85.4, respectively. This is the first report of the COX enzyme inhibitory activity for galactosyl glycerols and antiproliferative activities against human colon, breast, lung, stomach, and CNS tumor cell lines.     

Isolation and identification of strawberry phenolics with antioxidant and human cancer cell antiproliferative properties

Studies suggest that consumption of berry fruits, including strawberries ( Fragaria x ananassa Duch.), may have beneficial effects against oxidative stress mediated diseases such as cancer. Berries contain multiple phenolic compounds, which are thought to contribute to their biological properties. Comprehensive profiling of phenolics from strawberries was previously reported using high-performance liquid chromatography with mass spectrometry (HPLC-MS) detection. The current study reports the isolation and structural characterization of 10 phenolic compounds from strawberry extracts using a combination of Amberlite XAD16-resin and C18 columns, HPLC-UV, and nuclear magnetic resonance (NMR) spectroscopy methods. The phenolics were cyanidin-3-glucoside ( 1), pelargonidin (2), pelargonidin-3-glucoside (3), pelargonidin-3-rutinoside (4), kaempferol (5), quercetin (6), kaempferol-3-(6'-coumaroyl)glucoside) (7), 3,4,5-trihydroxyphenyl-acrylic acid (8), glucose ester of ( E)- p-coumaric acid (9), and ellagic acid . Strawberry crude extracts and purified compounds 1- 10 were evaluated for antioxidant and human cancer cell antiproliferative activities by the Trolox equivalent antioxidant capacity (TEAC) and luminescent ATP cell viability assays, respectively. Among the pure compounds, the anthocyanins 1 (7156 microM Trolox/mg), 2 (4922 microM Trolox/mg), and 4 (5514 microM Trolox/mg) were the most potent antioxidants. Crude extracts (250 microg/mL) and pure compounds (100 microg/mL) inhibited the growth of human oral (CAL-27, KB), colon (HT29, HCT-116), and prostate (LNCaP, DU145) cancer cells with different sensitivities observed between cell lines. This study adds to the growing body of data supporting the bioactivities of berry fruit phenolics and their potential impact on human health.     

Novel biological properties of Oenothera paradoxa defatted seed extracts: effects on metallopeptidase activity

In this study, for the first time, we used the in vitro metallopeptidase model for the identification of a potential novel activity of defatted evening primrose seed extracts. Prepared extracts of different polarity (aqueous, 60% ethanolic, isopropanolic, and 30% isopropanolic) at concentrations of 1.5-100 microg/mL exhibited a significant and dose dependent inhibition of three tested enzymes. The 50% inhibition of enzymes activity showed that aminopeptidase N (APN) was the enzyme affected to the greatest extent with IC50 at the level of 2.8 microg/mL and 2.9 microg/mL for aqueous and 30% isopropanolic extracts, respectively. The activity of neutral endopeptidase (NEP) was quite strongly inhibited by the extracts as well. The HPLC-DAD analysis and bioguided fractionation led to the identification of four active compounds: (-)-epicatechin gallate, proanthocyanidin B3, oenothein B, and penta-O-galloyl-beta-D-glucose (PGG). Oenothein B has been shown previously to inhibit metallopeptidases. The three other compounds are known to inhibit angiotensin-converting enzyme (ACE), but they have not been previously reported to inhibit the NEP and APN activity. PGG and procyanidins with different degrees of polymerization, as the dominating compounds in O. paradoxa seeds, seemed to play a role in the crude extract activity.     

Chitosan treatment of wheat seeds induces resistance to Fusarium graminearum and improves seed quality.

Chitosan treatment (2-8 mg/mL) of wheat seeds significantly improved seed germination to recommended seed certification standards (>85%) and vigor at concentrations >4 mg/mL, in two cultivars of spring wheat (Norseman and Max), by controlling seed-borne Fusarium graminearum infection. The germination was <80% in the control and >85% in benomyl- and chitosan-treated seeds. Seed-borne F. graminearum was reduced to >50% at higher chitosan treatments compared to the control. Synthesis of phenolic acids was stimulated in primary leaves following chitosan treatment, and levels of these phenolic acids, especially ferulic acid, increased significantly with increasing chitosan concentration. Lignin content of primary leaves also showed a similar pattern. The synthesis of precursors of lignin such as p-coumaric, ferulic, and sinapic acids and phenolic acids having antimicrobial activity such as benzoic, p-coumaric, caffeic, protocatechuic, chlorogenic, ferulic, and gallic acids was also stimulated by chitosan treatment. The induction of phenolic acids and lignin was significantly lower in cv. Max compared to Norseman. Chitosan also inhibited fungal transmission to the primary roots of germinating seedlings. Results suggest that chitosan controlled seed-borne F. graminearum infection and increased the resistance in seedlings by stimulating the accumulation of phenolics and lignin. Thus, chitosan has a potential for improvement of seed quality and enhancement of crop yields as well as increased value of stored grains for food and feed.     

Structure-function relationships of anthocyanins from various anthocyanin-rich extracts on the inhibition of colon cancer cell growth

Anthocyanins are potent antioxidants and may be chemoprotective. However, the structure-function relationships are not well understood. The objectives of this study were to compare the chemoprotective properties of anthocyanin-rich extracts (AREs) with variable anthocyanin profiles to understand the relationship between anthocyanin chemical structure and chemoprotective activity, measured as inhibition of colon cancer cell proliferation. Additionally, the chemoprotective interaction of anthocyanins and other phenolics was investigated. AREs with different anthocyanin profiles from purple corn, chokeberry, bilberry, purple carrot, grape, radish, and elderberry were tested for growth inhibition (GI 50) using a human colorectal adenocarcinoma (HT29) cell line. All AREs suppressed HT29 cell growth to various degrees as follows: purple corn (GI 50 approximately 14 microg of cy-3-glu equiv/mL) > chokeberry and bilberry > purple carrot and grape > radish and elderberry (GI 50 > 100 microg of cy-3-glu equiv/mL). Anthocyanins played a major role in AREs' chemoprotection and exerted an additive interaction with the other phenolics present. Statistical analyses suggested that anthocyanin chemical structure affected chemoprotection, with nonacylated monoglycosylated anthocyanins having greater inhibitory effect on HT-29 cell proliferation, whereas anthocyanins with pelargonidin, triglycoside, and/or acylation with cinnamic acid exerted the least effect. These findings should be considered for crop selection and the development of anthocyanin-rich functional foods.     

Hydroxycinnamic acids and ferulic acid dehydrodimers in barley and processed barley

Hydroxycinnamic acid content and ferulic acid dehydrodimer content were determined in 11 barley varieties after alkaline hydrolysis. Ferulic acid (FA) was the most abundant hydroxycinnamate with concentrations ranging from 359 to 624 microg/g dry weight. p-Coumaric acid (PCA) levels ranged from 79 to 260 microg/g dry weight, and caffeic acid was present at concentrations of <19 microg/g dry weight. Among the ferulic acid dehydrodimers that were identified, 8-O-4'-diFA was the most abundant (73-118 microg/g dry weight), followed by 5,5'-diFA (26-47 microg/g dry weight), the 8,5'-diFA benzofuran form (22-45 microg/g dry weight), and the 8,5'-diFA open form (10-23 microg/g dry weight). Significant variations (p < 0.05) among the different barley varieties were observed for all the compounds that were quantified. Barley grains were mechanically fractionated into three fractions: F1, fraction consisting mainly of the husk and outer layers; F2, intermediate fraction; and F3, fraction consisting mainly of the endosperm. Fraction F1 contained the highest concentration for ferulic acid (from 77.7 to 82.3% of the total amount in barley grain), p-coumaric acid (from 78.0 to 86.3%), and ferulic acid dehydrodimers (from 79.2 to 86.8%). Lower contents were found in fraction F2, whereas fraction F3 exhibited the lowest percentages (from 1.2 to 1.9% for ferulic acid, from 0.9 to 1.7% for p-coumaric acid, and <0.02% for ferulic acid dehydrodimers). The solid barley residue from the brewing process (brewer's spent grain) was approximately 5-fold richer in ferulic acid, p-coumaric acid, and ferulic acid dehydrodimers than barley grains.     

Phenolic acids, syringaldehyde, and juglone in fruits of different cultivars of Juglans regia L

Phenolic acids (chlorogenic, caffeic, p-coumaric, ferulic, sinapic, ellagic, and syringic acid) as well as syringaldehyde and juglone were identified in ripe fruits of 10 walnut cultivars: Adams, Cisco, Chandler, Franquette, Lara, Fernor, Fernette, Alsoszentivani 117 (A-117), Rasna, and Elit. Analyses were done using a high-performance liquid chromatograph equipped with a diode array detector. Significant differences in the contents of identified phenolics were observed among cultivars. Phenolics were determined separately in the kernel and in the thin skin of the walnut, termed the pellicle. Not only in the kernel but also in the pellicle did syringic acid, juglone, and ellagic acid predominate (average values of 33.83, 11.75, and 5.90 mg/100 g of kernel; and 1003.24, 317.90, and 128.98 mg/100 g of pellicle, respectively), and the contents of ferulic and sinapic acid (average values of 0.06 and 0.05 mg/100 g of kernel and 2.93 and 2.17 mg/100 g of pellicle, respectively) were the lowest in all cultivars. The highest differences in the sum of all identified phenolics were observed between Rasna and Fernette fruits; in Rasna there were >2-fold higher contents of identified phenolics in both kernel and pellicle. It was found that the walnut pellicle is the most important source of walnut phenolics. The ratio between the contents in pellicle and kernel varied by at least 14.8-fold for caffeic acid (cv. Adams) and by up to 752.0-fold for p-coumaric acid (cv. Elit).     

Purification and characterization of ferulic acid esterase from malted finger millet (Eleusine coracana, Indaf-15)

Ferulic acid esterase (EC 3.1.1.73) cleaves the feruloyl groups substituted at the 5'-OH group of arabinosyl residues of arabinoxylans and is known to modulate their functional properties. In this study, ferulic acid esterase from 96 h finger millet malt was purified to apparent homogeneity by three-step purification with a recovery of 3% and a fold purification of 22. The substrate p-nitrophenylferulate (PNPF) was synthesized and used to assay this enzyme spectrophotometrically. The products liberated from ragi and wheat water-soluble polysaccharides by the action of purified ragi ferulic acid esterase were identified by ESI-MS. The pH and temperature optima of the enzyme were found to be 6.0 and 45 degrees C, respectively. The pH and temperature stabilities of the enzyme were found to be in the range of 5.5-9.0 and 30 degrees C, respectively. The activation energy of the enzymatic reaction was found to be 4.08 kJ mol(-1). The apparent K m and V max of the purified ferulic acid esterase for PNPF were 0.053 microM and 0.085 unit mL(-1), respectively. The enzyme is a monomer with a molecular mass of 16.5 kDa. Metal ions such as Ni(2+), Zn(2+), Co(2+), and Cu(2+) and oxalic and citric acids enhanced the enzyme activity. The enzyme was completely inhibited by Fe(3+). Group specific reagents such as p-chloromercuric benzoate and iodoacetamide inhibited the enzyme, indicating the possible presence of cysteine residues in the active site pocket.     

In vitro inhibitory effect on pancreatic lipase activity of subfractions from ethanol extracts of fermented Oats (Avena sativa L.) and synergistic effect of three phenolic acids

The purpose of the present work is to study the pancreatic lipase inhibitory effects of different subfractions (n-hexane, ethyl acetate (EA), n-butanol, and water) from ethanol extracts of nonfermented and fungi-fermented oats and to delineate the interactions of three primary phenolic acids in the EA subfractions. The EA subfraction showed the highest inhibitory effect on pancreatic lipase activity at 1.5 mg/mL compared to the other subfractions, regardless of whether the oats were fermented. Meanwhile, both of the EA subfractions of two fungi-fermented oats demonstrated more effective inhibitory activity than that of nonfermented oats. A positive correlation between the total phenolics content and inhibitory activity was found. The inhibitory ability of the EA subfraction from nonfermented or fermented oats also displayed a dose-dependent effect. The standards of caffeic, ferulic, and p-coumaric acids, mainly included in EA subfractions of fermented oats, also displayed a dose-dependent inhibitory effect. A synergistic effect of each binary combination of p-coumaric, ferulic, and caffeic acids was observed, especially at 150.0 μg/mL. Those results indicate that fungi-fermented oats have a more effective inhibitory ability on pancreatic lipase and polyphenols may be the most effective component and could be potentially used for dietary therapy of obesity.     

Absorption of 6-O-caffeoylsophorose and its metabolites in Sprague-Dawley rats detected by electrochemical detector-high-performance liquid chromatography and electrospray ionization-time-of-flight-mass spectrometry methods

Absorption and metabolism of a natural compound, 6-O-caffeoylsophorose (CS) from acylated anthocyanins in a red vinegar fermented with purple sweet potato, were clarified. The absorption of CS and conjugated CS in blood from orally administrated Sprague-Dawley rats at a dose of 400 mg/kg was investigated by electrochemical detection-high performance liquid chromatography. As a result, CS was successfully detected in rat plasma (AUC(0-6h), 108.6 ± 8.1 nmol h/mL) and was found to be an intact absorbable polyphenol. In addition, half of the absorbed CS was detected as its conjugates (AUC(0-6h), 50.7 ± 5.7 nmol h/mL) as well as caffeic and ferulic acids from CS. By a time-of-flight-mass spectrometric analysis of CS-administered plasma sample, glucuronide and methylated conjugates of CS were identified, in addition to glucuronide, methylated, or sulfate conjugates of caffeic and ferulic acids. Consequently, CS was absorbed in intact form into rat blood and partly degraded to caffeic and ferulic acids or metabolized by glucuronidation, methylation, or sulfatation.     

Comparison of antioxidant activity, anthocyanins, carotenoids, and phenolics of three native fresh and sun-dried date (Phoenix dactylifera L.) varieties grown in Oman

Fresh and sun-dried dates of three native varieties from Oman, namely, Fard, Khasab, and Khalas, were examined for their antioxidant activity and total contents of anthocyanins, carotenoids, and phenolics, as well as free and bound phenolic acids. All results are expressed as mean value +/- standard deviation (n = 3) on a fresh weight basis. Fresh date varieties were found to be a good source of antioxidants (11687-20604 micromol of Trolox equiv/g), total contents of anthocyanins (0.24-1.52 mg of cyanidin 3-glucoside equiv/100 g), carotenoids (1.31-3.03 mg/100 g), phenolics (134-280 mg of ferulic acid equiv/100 g), free phenolic acids (2.61-12.27 mg/100 g), and bound phenolic acids (6.84-30.25 mg/100 g). A significant (p < 0.05) amount of antioxidants and carotenoids was lost after sun-drying of dates, whereas the total content of phenolics and free and bound phenolic acids increased significantly (p < 0.05). Anthocyanins were detected only in fresh dates. Date varieties had different levels and patterns of phenolic acids. Four free phenolic acids (protocatechuic acid, vanillic acid, syringic acid, and ferulic acid) and nine bound phenolic acids (gallic acid, protocatechuic acid, p-hydroxybenzoic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, and o-coumaric acid) were tentatively identified. Of the date varieties studied, Khalas, which is considered to be premium quality, had higher antioxidant activity, total carotenoids, and bound phenolic acids than other varieties. These results suggest that all date varieties serve as a good source of natural antioxidants and could potentially be considered as a functional food or functional food ingredient, although some of their antioxidant constituents are lost during sun-drying.     

Cyclooxygenase inhibitory and antioxidant compounds from the mycelia of the edible mushroom Grifola frondosa

The bioassay-guided isolation and purification of the hexane extract of the cultured mycelia of Grifola frondosa led to the characterization of a fatty acid fraction and three compounds, ergosterol (1), ergostra-4,6,8(14),22-tetraen-3-one (2), and 1-oleoyl-2-linoleoyl-3-palmitoylglycerol (3). The composition of fatty acid fraction was confirmed as palmitic, oleic, and linoleic acids by GC-MS and by comparison with the retention values of authentic samples. The structures of compounds 1-3 were established by spectroscopic methods. The fatty acid fraction and compounds 1-3 showed cyclooxygenase (COX) enzyme inhibitory and antioxidant activities. The inhibition of COX-1 enzyme by the fatty acid fraction and compounds 1-3 at 250 microg/mL were 98, 37, 55, and 67%, respectively. Similarly, COX-2 enzyme activity was reduced by fatty acid fraction and compounds 1-3 at 250 microg/mL by 99, 37, 70, and 4%, respectively. The inhibitions of liposome peroxidation by the fatty acid fraction and compounds 1 and 2 at 100 microg/mL were 79, 48, and 42%, respectively. This is the first report of compounds 2 and 3 from the cultured mycelia of G. frondosa. The COX inhibitory activities of compounds 1-3 are reported here for the first time.     

Bioactive compounds and 1,3-Di[(cis)-9-octadecenoyl]-2-[(cis,cis)-9, 12-octadecadienoyl]glycerol from Apium graveolens L. seeds

Bioassay-directed isolation and purification of the hexane extract of Apium graveolens L. seeds led to the characterization of three compounds: beta-selinene (1), 3-n-butyl-4,5-dihydrophthalide (2) and 5-allyl-2-methoxyphenol (3). The structures of these compounds were established by using (1)H and (13)C NMR spectral methods. Compounds, 1-3 demonstrated 100% mortality on fourth-instar Aedes aegyptii larvae at 50, 25, and 200 microg mL(-)(1), respectively, in 24 h. Also, 2 inhibited the growth of Candida albicans and Candida kruseii at 100 microg mL(-)(1). It inhibited both topoisomerase-I and -II enzyme activities at 100 microg mL(-)(1). Compound 2 displayed 100% mortality at 12.5 and 50 microg mL(-)(1), respectively, when tested on nematodes, Panagrellus redivivus and Caenorhabditis elegans. The triglyceride, 1,3-di[(cis)-9-octadecenoyl]-2-[(cis,cis)-9, 12-octadecadienoyl]glycerol (4) and 3 were isolated for the first time from A. graveolens seeds, although 4 was not biologically active.     

Inhibitory effect of caffeic acid phenethyl ester on angiogenesis, tumor invasion, and metastasis

Caffeic acid phenethyl ester (CAPE) derived from honeybee propolis has been used as a folk medicine and has several proven biological activities. The present study investigated the effect of CAPE on angiogenesis, tumor invasion, and metastasis. A cytotoxicity assay of CAPE in CT26 colon adenocarcinoma cells showed a dose-dependent decrease in cell viability but no significant influence on the growth of human umbilical vein epithelial cells (HUVEC). A low concentration of CAPE (1.5 microg/mL) inhibited 52.7% of capillary-like tube formation in HUVEC culture on Matrigel. CAPE (6 microg/mL)-treated CT26 cells showed not only inhibited cell invasion by 47.8% but also decreased expression of matrix metalloproteinase (MMP)-2 and -9. Vascular endothelial growth factor (VEGF) production from CT26 cells was also inhibited by treatment with CAPE (6 microg/mL). Intraperitoneal injection of CAPE (10 mg/kg/day) in BALB/c mice reduced the pulmonary metastatic capacity of CT26 cells accompanied with a decreased plasma VEGF level. CAPE treatment also prolonged the survival of mice implanted with CT26 cells. These results indicate that CAPE has potential as an antimetastatic agent.