Studies on the constituents of Cyclanthera pedata fruits: isolation and structure elucidation of new triterpenoid saponins.

The isolation of nine triterpenoid saponins (1-9), among them six new natural compounds (1-6), from the MeOH extract of the fruits of Cyclanthera pedata is reported. All of the structures were elucidated by spectroscopic methods, including the concerted application of one-dimensional (1)H-(1)H total correlation spectroscopy, (1)H-(1)H nuclear Overhauser effect spectroscopy), and (13)C-(13)C DEPT-NMR and two-dimensional NMR techniques (double-quantum filtered correlated spectroscopy, rotating-frame Overhauser enhancement spectroscopy, heteronuclear single quantum coherence, and heteronuclear multiple bond correlation). A comparative study of seeds and fruits has been also carried out.     

Garcinol promotes neurogenesis in rat cortical progenitor cells through the duration of extracellular signal-regulated kinase signaling

Garcinol is a polyisoprenylated benzophenone derivative found in Garcinia indica fruit rind and other species. The potential antioxidative and neuroprotective effects of garcinol in rat cortical astrocyte were demonstrated in our laboratory recently. Here, the effects of garcinol on the neuritogenesis process in cultured cortical progenitor cells were investigated to understand the roles of garcinol in neuronal survival and differentiation. These cells, derived from embryonic day 17 rats, differentiated into EGF-responsive neural precursor cells, would further form neurospheres. Our data exhibited garcinol induced neurite outgrowth in early developing EGF-treated neurospheres and significantly enhanced the expression of neuronal proteins, microtubule-associated protein 2 (MAP-2), and glial fibrillary acidic protein (GFAP). Furthermore, the neuronal marker, high-molecular-weight subunit of neurofilaments (NFH), was highly expressed after 5 μM garcinol treatment in neural precursor cells for 20 days. To identify the extracellular mechanism, rat cortical progenitor cells were treated garcinol and accordingly mediated the sustained activation of extracellular signal-regulated kinase (ERK) for different periods up to 20 h. In this regard, NMDA receptor-mediated calcium influx led to excitotoxic death and activated tyrosine phosphatase which limited the duration of ERK in cultured neurons. MK801, the NMDA receptor antagonist, treatment also induced the sustained phosphorylation of ERK and therefore enhanced neuronal survival. In our observation, garcinol treatment reduced growth factor deprivation-mediated cell death and nuclear import of C/EBPβ levels. Noteworthy, garcinol could promote neurite outgrowth in EGF-responsive neural precursor cells and modulate the ERK pathway in the enhancement of neuronal survival.     

Effects of Potassium Application on Flavor Compounds of Cherry Tomato Fruits

ABSTRACT

A pot experiment was conducted to determine the effects of potassium (K) application on volatile compounds, taste compounds, and firmness of fresh tomato fruits. Each pot was filled with 8 kg of clean sand. The experiment consisted of six K application rates with 0, 1.25, 2.5, 5.0, 10.0, and 20.0 mmol K L^?1 in the nutrient solution. Volatile compounds, soluble sugars, soluble solids, titratable acidity, and firmness of fresh tomato fruits were measured. The results show that the concentrations of 3-methylbutanal, 1-penten-3-one, hexanal, cis-3-hexenal, 2-methyl-4-pentenal, trans-2-hexenal, 2E-4E-hexadienal, 6-methyl-5-hepten-2-one, phenylacetaldehyde, phenylethanol, soluble sugars, and soluble solids tended to increase at first and then decrease between 0 to 10.0 mmol K L^?1. K application rate obtaining the highest values of the concentrations ranged from 1.4 to 3.0 mmol K L^?1, with the exception of cis-3-hexenal (1.1 mmol K L^?1), phenylacetaldehyde (4.5 mmol K L^?1), and phenylethanol (4.8 mmol K L^?1). By contrast, increasing K supply increased the concentration of titratable acidity, decreased the ratios of soluble sugars to titratable acidity and soluble solids to titratable acidity. Close correlations were observed between the concentrations of various volatile compounds, soluble sugars, and soluble solids. Based on contributions of these compounds to tomato flavor, we assume that moderate K supply (1.4–3.0 mmol K L^?1) improves tomato flavor, whereas tomato fruits with either no K or high K fertilization have poor flavor due to having undesirable levels of flavor compounds.     

Studies on the constituents of Cyclanthera pedata fruits: isolation and structure elucidation of new flavonoid glycosides and their antioxidant activity.

The isolation of six flavon glycosides (1-6), among them four new natural compounds (1-4), from the CHCl(3)/MeOH extract of the fruits of Cyclanthera pedata is reported. All of the structures were elucidated by spectroscopic methods, including the concerted application of one-dimensional ((1)H, (1)H TOCSY, (13)C, and (13)C DEPT-NMR) and two-dimensional NMR techniques (DQF-COSY, HSQC, and HMBC). For all of the isolated compounds the antioxidant activity was determined by measuring the free radical scavenging activity, using the Trolox equivalent antioxidant capacity (TEAC) method, and the coupled oxidation of beta-carotene and linoleic acid.     

Bioactive compounds of grapefruit (Citrus paradisi Cv. Rio Red) respond differently to postharvest irradiation, storage, and freeze drying

In the present study, the effect of irradiation, storage, and freeze drying on grapefruit bioactive compounds was investigated. Grapefruits were exposed to one of two irradiation doses: 0 (control) or 300 Gy (137Cs, a proposed treatment against fruit flies) and then stored for up to 6 days. At the last storage time point (6 days after harvest), grapefruit pulp from control and irradiated fruits was freeze-dried. Bioactive compounds were extracted from Rio Red grapefruit pulp and analyzed with reverse phase liquid chromatography while volatile compounds were analyzed using gas chromatography. Freeze-dried pulp from irradiated fruits had a higher (P < or = 0.05) flavonoid content (naringin and narirutin) as compared to the freeze-dried pulp from the control fruits. Freeze-drying treatment reduced (P < or = 0.05) the lycopene content, but the reduction (P < or = 0.05) in beta-carotene content occurred only in the control fruit. Reduction in d-limonene and myrcene was observed in the irradiated fruits at 6 days after harvest and in the freeze-dried samples. These results warrant testing of the effect of postharvest treatments and processing on bioactive compounds in functional systems as they have varied effects on different bioactive compounds of grapefruit.     

Free radical scavenging activity and antiulcer activity of garcinol from Garcinia indica fruit rind

Garcinol, a polyisoprenylated benzophenone derivative, was purified from Garcinia indica fruit rind, and its free radical scavenging activity was studied using electron spin resonance (ESR) spectrometry. In the hypoxanthine/xanthine oxidase system, emulsified garcinol suppressed superoxide anion to almost the same extent as DL-alpha-tocopherol by weight. In the Fenton reaction system, garcinol also suppressed hydroxyl radical more strongly than DL-alpha-tocopherol. In the H(2)O(2)/NaOH/DMSO system, garcinol suppressed superoxide anion, hydroxyl radical, and methyl radical. It was thus confirmed that this derivative is a potent free radical scavenger and able to scavenge both hydrophilic and hydrophobic ones including reactive oxygen species. Orally administered garcinol prevented acute ulceration in rats induced by indomethacin and water immersion stress caused by radical formation. These results suggested garcinol might have potential as a free radical scavenger and clinical application as an antiulcer drug.     

Induction of apoptosis by garcinol and curcumin through cytochrome c release and activation of caspases in human leukemia HL-60 cells

Garcinol, a polyisoprenylated benzophenone, was purified from Garcinia indica fruit rind. The effects of garcinol and curcumin on cell viability in human leukemia HL-60 cells were investigated. Garcinol and curcumin displayed strong growth inhibitory effects against human leukemia HL-60 cells, with estimated IC(50) values of 9.42 and 19.5 microM, respectively. Garcinol was able to induce apoptosis in a concentration- and time-dependent manner; however, curcumin was less effective. Treatment with garcinol caused induction of caspase-3/CPP32 activity in a dose- and time-dependent manner, but not caspase-1 activity, and induced the degradation of poly(ADP-ribose) polymerase (PARP). Pretreatment with caspase-3 inhibitor inhibited garcinol-induced DNA fragmentation. Treatment with garcinol (20 microM) caused a rapid loss of mitochondrial transmembrane potential, release of mitochondrial cytochrome c into cytosol, and subsequent induction of procaspase-9 processing. The cleavage of D4-GDI, an abundant hematopoietic cell GDP dissociation inhibitor for the Ras-related Rho family GTPases, occurred simultaneously with the activation of caspase-3 but preceded DNA fragmentation and the morphological changes associated with apoptotic cell death. Of these, Bcl-2, Bad, and Bax were studied. The level of expression of Bcl-2 slightly decreased, while the levels of Bad and Bax were dramatically increased in cells treated with garcinol. These results indicate that garcinol allows caspase-activated deoxyribonuclease to enter the nucleus and degrade chromosomal DNA and induces DFF-45 (DNA fragmentation factor) degradation. It is suggested that garcinol-induced apoptosis is triggered by the release of cytochrome c into the cytosol, procaspase-9 processing, activation of caspase-3 and caspase-2, degradation of PARP, and DNA fragmentation caused by the caspase-activated deoxyribonuclease through the digestion of DFF-45. The induction of apoptosis by garcinol may provide a pivotal mechanism for its cancer chemopreventive action.     

HPLC-PDA-MS/MS of anthocyanins and carotenoids from dovyalis and tamarillo fruits

Anthocyanins and carotenoids are natural pigments responsible for the color of vegetables and fruits, and they are also bioactive compounds, both demonstrating important biological, therapeutic, and preventative properties. Considering the biodiversity of edible fruits, high performance liquid chromatography coupled to photodiode array and mass spectrometry detectors (HPLC-PDA-MS) was used to establish the composition of carotenoids and anthocyanins from dovyalis and tamarillo fruits. Ten anthocyanins and 26 carotenoids were found in dovyalis, whereas tamarillo showed 3 anthocyanins and 17 carotenoids. Higher contents of anthocyanins and carotenoids were found in dovyalis, 42.0 and 6.6 mg/100 g, respectively, as compared to tamarillo fruits with 8.5 and 4.4 mg/100 g, respectively. Although these fruits belong to different families, delphinidin 3-rutinoside and beta-cryptoxanthin were found to be, respectively, the major anthocyanin and carotenoid in both fruits.     

Chemical constituents of Morinda citrifolia fruits inhibit copper-induced low-density lipoprotein oxidation

The oxidative modification of low-density lipoprotein (LDL) plays an important role in the genesis of arteriosclerosis. The present study focused on the effects of the fruits of Morinda citrifolia on preventing arteriosclerosis. The MeOH extract and CHCl(3)-, EtOAc-, n-BuOH-, and H(2)O-soluble phases derived from the fruits of M. citrifolia were evaluated for their inhibitory activity on copper-induced LDL oxidation by the thiobarbituric acid-reactive substances (TBARS) method. The MeOH extract and EtOAc-soluble phase showed 88 and 96% inhibition, respectively. Six lignans were isolated by repeated column chromatography from the EtOAc-soluble phase. These compounds were determined by spectroscopic analysis to be 3,3'-bisdemethylpinoresinol (1), americanol A (2), americanin A (3), americanoic acid A (4), morindolin (5), and isoprincepin (6), of which 4 and 5 are novel compounds. These compounds inhibited copper-induced LDL oxidation in a dose-dependent manner. 1, 2, 5, and 6 exhibited remarkably strong activities, which were the same or better than that of the known antioxidant 2,6-di-tert-butyl-p-cresol. The IC(50) values for 1, 2, 5, and 6 were 1.057, 2.447, 2.020, and 1.362 microM, respectively. The activity of these compounds is mainly due to their number of phenolic hydroxyl groups.     

New constituents of sweet Capsicum annuum L. fruits and evaluation of their biological activity

Four new acyclic diterpene glycosides named capsianosides (1-4), together with 12 known compounds, were isolated from the fresh sweet pepper fruits of Capsicum annuum L., a plant used as a vegetable food, spice, and external medicine. The chemical structures of new natural compounds, as well as their absolute configurations, were established by means of spectroscopic data including infrared, high-resolution mass spectrometry, and one- and two-dimensional nuclear magnetic resonance and by chemical derivatization. The known capsidiol (11) showed bacteriostatic properties in vitro against Helicobacter pylori with a minimum inhibitory concentration (MIC) of 200 microg/mL when compared with the commercial drug metronidazole (MIC, 250 microg/mL). Some purified components were also tested for their antioxidant activities.     

Mineral Concentration,Sugar Content and Yield of Iranian ‘Khatooni’ Melon Affected by Grafting,Pruning and Thinning

Macroelements in leaves and fruits, sugar of fruits, and yield of ‘Khatooni’ melon were compared with melons grafted onto rootstocks cvs. ‘Ace’, ‘Shintozwa’, and ‘ShintoHongto’, and trained into three methods: T1) no pinching and fruit thinning; T2) pinched to produce two lateral branches; and T3) pinched to two branches and all flowers and lateral branches from lower nodes thinned. Concentrations of nitrogen (N), phosphorus (P), and potassium (K) increased in leaves onto ‘Shintozwa’, whereas opposite trends observed for magnesium (Mg) and calcium (Ca). N, P, and K in leaves were significantly higher by 21.5%, 17.2%, and 18.6%, respectively in grafted. N, P and K in fruits onto ‘Ace’ and ‘Shintozwa’ were higher, with exception of Ca and Mg in non-grafted. ‘Ace’ and ‘Shintozwa’ resulted in significant increase in Khatooni yield. T3 showed the highest yield. Soluble solids concentration (SSC) was higher in non-grafted fruits. T2 produced fruits with the highest SSC.     

Changes in physicochemical characteristics and volatile constituents of strawberry (Cv. Cigaline) during maturation

Changes in the volatile composition of strawberries (cv. Cigaline) at six stages of maturity, from 28 to 44 days after anthesis, were investigated over two harvesting seasons. Volatiles were isolated by direct solvent extraction and analyzed by means of GC-FID and GC-MS, with special attention to the quantification of furanones. Firmness, skin color, soluble solids (SS), titratable acidity (TA), SS/TA ratio, organic acids, and sugars were also determined. With increasing maturity, soluble solids, SS/TA ratio, Minolta a value, and levels of sucrose, glucose, fructose, and malic acid increased, whereas Minolta L value, hue angle (), titratable acidity, and levels of citric acid decreased. Furanones and esters were generally not detected before half-red fruits, whereas C(6) compounds were the main compounds in immature fruits. During maturation, levels of these so-called green components decreased drastically, whereas levels of key flavor compounds increased significantly and were closely correlated with skin color development. Maximum volatile production was observed in fully red fruits.     

施钾对有些茄科作物产量和品质的影响

Over a period of two years,field experiments were conducted on wto silty loam soils grown with four solanaceous vegetable crops of geggplant(var.serpentinum Bailey),tomato(var.commune Bailey),sweet pepper(var.grossum Bailey) and chilli (var.lengum Bailey),respectively,Each experiment included four treatments with from low to high doses,0-450 kg ha^-1 for eggplant ,tomato and sweet pepper,and 0-270 kg ha^-1 for chilli,of K fertilizers in the from of sulfate of potash(SOP) applied together with N and P fertilizers. One CK treatment without K,N and P fertilzers applied and one treatment of K fertilizer in the form of muriate of potash(MOP) applied at the high level(450kg ha^-1) together with N and P fertilizers were included in the experiments of eggplant,in order to compare the effects of SOP and MOP,The fruit yields of the tested crops increased significantly with the increasing rate of K application.The crops supplied with K fertilizers yielded more stably as the CV% of their yields decreased with the rate of K application,The K fertilizers yielded more stably as the CV% of their yields decreased with the rate of K application,The dry matter and vitamin C contents in fruits of tomato,sweet pepper and chilli,and the sugar content and the titratable acidity level of tomato fruits were increased,and the S/A ratio( ratio of sugar content to titratable acidity) of tomato fruits were decreased by K fertilization,indicating that K fertilization could improve the fruit quality of the solanaceous vegetable crops.However,the high rate of Kfertilizer might lower the dry matter and vitamin C contents of tomato fruits and sewwt pepper fruits.SOP was more effective than MOP in increasing the yield and quality of eggplant fruits at the high fertilization rate;therefore,the choice of applying SOP may be better for high levels of K fertilization.     

Ascorbic acid, phenolic acid, flavonoid, and carotenoid profiles of selected extracts from Ribes nigrum

Small fruits such as berries have low energy contents, but high contents of vitamins, micronutrients, and dietary fibers and constitute a good source of natural antioxidant compounds that are important constituents of the human diet. This study identified a large number of compounds in an extract of black currant showing high antioxidant activity and compared their profile in various parts of the plants (leaves, buds, and berries). If it was known that berries contained very high levels of natural phenolic compounds, this study showed that leaves and buds could also be considered good sources of natural antioxidants. Indeed, they contained high amounts of phenolic acids, flavonoids, and carotenoids. An acetone mixture can extract several classes of phenolic compounds with a good yield of flavonols, flavan-3-ols, and anthocyanins.     

Phenolic compounds in hawthorn (Crataegus grayana) fruits and leaves and changes during fruit ripening

Phenolics in the fruits and leaves of Crataegus grayana were identified by HPLC-UV-ESI-MS. The contents of these compounds and their changes during autumn were also analyzed. Epicatechin [1-7 mg/g dry mass (DM) in fruits and 1-10 mg/g DM in leaves), procyanidins B2 (2-4 and 1-8 mg/g DM) and C1 (2-4 and 1-8 mg/g DM), hyperoside (0.5-1 and 2-11 mg/g DM), and a quercetin-pentoside (0.3-0.5 and 2-6 mg/g DM) were the major phenolics in both fruits and leaves. C-Glycosyl flavones were present in leaves (2-5 mg/g DM), whereas only trace levels were found in fruits. Ideain and 5-O-caffeoylquinic acid were found only in fruits. An additional 11 phenolics were identified/tentatively identified. Total phenolic contents reached highest levels by the end of August in fruits and by the end of September in leaves. The compositional profiles of phenolics in fruits and leaves of C. grayana were different from those of other Crataegus species.     

Isolation of cholinesterase-inhibiting flavonoids from Morus lhou

Cholinesterases are key enzymes that play important roles in cholinergic transmission. Nine flavonoids displaying cholinesterase inhibitory activity were isolated from the root bark of Morus lhou L., a cultivated edible plant. The isolated compounds were identified as a new flavone (1), 5'-geranyl-5,7,2',4'-tetrahydroxyflavone (2), kuwanon U (3), kuwanon E (4), morusin (5), morusinol (6), cyclomorusin (7), neocyclomorusin (8), and kuwanon C (9). All compounds apart from compound 6 inhibited cholinesterase enzyme in a dose-dependent manner with K(i) values ranging between 3.1 and 37.5 μM and between 1.7 and 19.1 μM against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) enzymes, respectively. The new compound was charactierized as 5'-geranyl-4'-methoxy-5,7,2'-trihydroxyflavone (1). It showed the most potent inhibitory activity (K(i) = 3.1 μM for AChE, K(i) = 1.74 μM for BChE). Lineweaver-Burk and Dixon plots and their secondary replots indicated that flavones (5-9) with prenyl substitution on C-3 were noncompetitive inhibitors, whereas those unsubstituted (1-4) at C-3 were mixed inhibitors of both AChE and BChE. In conclusion, this is the first study to demonstrate that alkylated flavonoids of M. lhou have potent inhibitory activities against AChE and BChE.     

Postharvest treatments with salicylic acid, acetylsalicylic acid or oxalic acid delayed ripening and enhanced bioactive compounds and antioxidant capacity in sweet cherry

Sweet cherry cultivars ('Cristalina' and 'Prime Giant') harvested at commercial ripening stage were treated with salicylic acid (SA), acetylsalicylic acid (ASA) or oxalic acid (OA) at 1 mM and then stored for 20 days under cold temperature. Results showed that all treatments delayed the postharvest ripening process, manifested by lower acidity, color changes and firmness losses, and maintained quality attributes for longer periods than controls. In addition, total phenolics, anthocyanins and antioxidant activity increased in untreated fruit during the first 10 days of storage and then decreased, while in fruits of all treatments, these parameters increased continuously during storage without significant differences among treatments. Thus, postharvest treatments with natural compounds, such as SA, ASA or OA, could be innovative tools to extend the storability of sweet cherry with higher content of bioactive compounds and antioxidant activity as compared with control fruits.     

Evaluation of antioxidant activity of some natural polyphenolic compounds using the Briggs-Rauscher reaction method

A new method based on the inhibitory effects of antioxidants on the oscillations of the hydrogen peroxide, acidic iodate, malonic acid, and Mn(II)-catalyzed system (known as the Briggs-Rauscher reaction), was used for the evaluation of antioxidative capacity. With this method, which works near the pH of the fluids in the stomach (pH approximately 2), a group of natural compounds present in fruits and vegetables or in medicinal plants assumed to have antioxidant capacity, was tested successfully. The aim of the present study is to evaluate the antioxidative properties of some active principles contained in vegetables and aromatic plants, namely, cynarin (from Cynara scolymus), rosmarinic acid (from Rosmarinus officinalis), echinacoside (from Echinacea species), puerarin (from Pueraria lobata), and oleuropein (from Olea europea). Also studied with the Briggs-Rauscher reaction method was the antioxidant activity of cyanidin 3-O-beta-glucopyranoside (from Citrus aurantium) in order to compare the results with those obtained by other methods. The conclusions on the dependency of the antioxidative activity on the pH of the testing system are given.     

Effect of treated sewage water on vegetative and reproductive growth of date palm

Abstract

The effect of treated sewage water on the vegetative and reproductive growth of date palms was assessed. Leaves and fruits samples were collected from locations irrigated with treated sewage (TSW), desalinised, and well water. Samples were analysed for their calcium (Ca), magnesium (Mg), iron (Fe), lead (Pb), copper (Cu), and zinc (Zn) content by atomic absorption spectro‐photometry and for sodium (Na) and potassium (K) by flame photometry. The Mg, Fe, and Zn content of fruits and Na in the leaves were not found to be significantly different. Treated sewage water from University campus utilities significantly increased the Na, K, and Cu and reduced Ca in leaves and Zn in fruits of date palms. But no significant effect was observed on the K, Ca, Mg, and Na contents in fruits of the same palms. The different concentrations of Ca, Mg, Fe, and Zn in the fruits of date palms grown along the same TSW line were attributed to variations in the soil; however, those in Pb content of leaves could be attributed to motor vehicle combustion. The general trend indicated that fruits contained higher K, Na, and Fe contents, but lower Ca, Mg, Cu, Zn, and Pb contents than the leaves. Furthermore, leaves of date palms irrigated with desalinised and well water contained higher Ca and Zn, but lower K, Mg, Na, Cu, Fe, and Pb contents than those of palms irrigated with treated sewage water. Desalinised water reduced the K, Ca, Na, and Zn contents, but it increased the Mg, Fe, Cu, and Pb content of leaves compared to well water. None of the examined metals were found to reach toxic level to man or plant.     

Volatile constituents and key odorants in leaves, buds, flowers, and fruits of Laurus nobilis L

The volatiles of fresh leaves, buds, flowers, and fruits from bay (Laurus nolilis L.) were isolated by solvent extraction and analyzed by capillary gas chromatography-mass spectrometry. Their odor quality was characterized by gas chomatography-olfactometry-mass spectrometry (HRGC-O-MS) and aroma extract dilution analysis (AEDA). In fresh bay leaves 1,8-cineole was the major component, together with alpha-terpinyl acetate, sabinene, alpha-pinene, beta-pinene, beta-elemene, alpha-terpineol, linalool, and eugenol. Besides 1,8-cineole and the pinenes, the main components in flowers were alpha-eudesmol, beta-elemene, and beta-caryophyllene, in fruits (E)-beta-ocimene and biclyclogermacrene, and in buds (E)-beta-ocimene and germacrene D. The aliphatic ocimenes and farnesenes were absent in leaves. By using HRGC-O-MS 21 odor compounds were identified in fresh leaves. Application of AEDA revealed (Z)-3-hexenal (fresh green), 1,8-cineole (eucalyptus), linalool (flowery), eugenol (clove), (E)-isoeugenol (flowery), and an unidentified compound (black pepper) with the highest flavor dilution factors. Differences between buds, flowers, fruits, and leaves with regard to the identified odor compounds are presented.