Effects of pH, sample size, and solvent partitioning on recovery of soluble phenolic acids and isoflavonoids in leaves and stems of red clover (Trifolium pratense cv. Kenland)

Several extraction parameters were tested to determine optimal conditions for extracting phenolics from leaves and stems of red clover (Trifolium pratense L. cv. Kenland), with the goal of using extracts in bioassays and in assessment of phenolic profiles. HPLC-UV profiles were compared before and after partitioning a methanolic extract of soluble phenolics with ethyl acetate-ethyl ether (1:1, v/v). The effect of extract pH on the partitioning of phenolics into the ethyl acetate-ethyl ether (EtOAc-Et2O) phase was evaluated, and several tissue weights were extracted to determine a minimum amount that could be extracted without loss of information. HPLC profiles of soluble phenolics were similar in the methanolic extracts and the partitioned EtOAc-Et2O extracts. However, recoveries in unpartitioned extracts were 2- to 4-fold greater than in the acidified, partitioned extracts. Also, recovery was considerably affected by the pH to which extracts were adjusted prior to partitioning. In extracts acidified to pH 2, recoveries were 2- to 7-fold higher than in extracts partitioned at pH 6. In extracts prepared from 250, 120, or 60 mg of tissue, peak areas of methanolic extracts were directly proportional to the amount of tissue extracted.     

Effects of silver nanoparticles on seed germination and seedling growth: A review

The advancement in nanotechnology, nanoparticles are reported to have applications in various fields. Their positive role in the environment, especially in plant ecosystem, is extensively studied nowadays. Among the metal nanoparticles, the silver nanoparticles (AgNPs) are receiving special attention because of their ability to increase the growth and yield in many crops. Although many studies are found that shows the toxic effects of AgNPs, the perspective of the present review is to collect the information about their positive roles in growth and yield enhancement of crops. During this overview, there are many methods of synthesizing silver AgNPs nanoparticles discussed, including chemical, bacterial-induced, fungal-derived and plant-mediated synthesis. There are numerous approaches towards the synthesis of AgNPs, including biological and chemical methods. Because of the use of reducing agents such as sodium borohydride in the synthesis of AgNPs, conventional methods have opened a path that threatens environmental sustainability. The chemical synthesis of silver colloids is the consequence of increased aggregation as storage time increases. AgNPs possess unique properties which has many applications such as antimicrobial and anticancer activities. It was concluded that cautious and sensible use of nanotechnology can warrant food security through boosting agricultural production. This review is aimed at providing an insight into the syntheses of AgNPs, its significant applications in various fields, and characterization techniques involved.     

The influence of sunflower and mustard leaf extracts on the germination of mustard seeds

The extracts from sunflower and mustard leaves were separated using SPE-Columns. The mustard seeds were germinated on water (24 h) and subsequently on crude extracts or separate fractions. The heat production rate was measured by isothermal calorimetry at 21°C and changes in seed cotyledons by FT-Raman spectroscopy. Crude extracts strongly inhibited seed germination. The water and ‘methanol’ fractions of mustard and sunflower extracts have a similar influence on the pattern of heat efflux. FT-Raman spectroscopy showed that extracts caused changes in cotyledons mainly in the content of fatty acids, carotenoids and flavonoids. Isothermal calorimetry and Raman spectroscopy are useful for the study of allelopathic interactions.     

Study of allelopathic effects of Eucalyptus erythrocorys L. crude extracts against germination and seedling growth of weeds and wheat

Allelopathic materials inside a tree can produce positive or negative change in the survival, growth, reproduction and behaviour of other organisms if they escape into the environment. To assess these effects, this work was carried out to evaluate the allelopathic impact of Eucalyptus erythrocorys L. on seed germination and seedling growth of two weeds: Sinapis arvensis L. and Phalaris canariensis L.; on one cultivated crop: Triticum durum L. Aqueous; and on ethanolic leaf extracts of E. erythrocorys L. The study was effected using four concentrations (10, 20, 25 and 30 μL/mL) while distilled water was used as a control. The results showed that the E. erythrocorys L. crude extracts had an inhibitory effect on seed germination and seedling growth of both studied weeds and wheat. The inhibition rate was increased by the increase in extract concentration. Only ethanolic extracts of E. erythrocorys L. induced a significant inhibition of seed germination of durum wheat. The effect of E. erythrocorys L. crude extracts was more severe on weeds than on durum wheat. These results indicate that the seedling growth, especially radicle elongation, was the more sensitive indicator to evaluate the effects of extracts than was the seed germination.     

Capsaicinoids from hot pepper (Capsicum annuum L.) and their phytotoxic effect on seedling growth of lettuce (Lactuca sativa L.)

Abstract

One new capsaicinoid, N-vanillyl-4E,6E-dien-8-methylnonanamide (4), along with nine known capsaicinoids, capsaicin (1), dihydrocapsaicin (2), N-vanillyloctanamide (3), nordihydrocapsaicin (5), N-vanillyldecanamide (6), homocapsaicin (7), N-vanillyl-4,8-dimethylnonanamide (8), homodihydrocapsaicin II (9), and homodihydrocapsaicin I (10) were isolated from the fruits of Capsicum annuum using semi-preparative high-performance liquid chromatography. The structural characterizations of the isolated compounds were elucidated by spectroscopic data and comparison with the literatures. Bioassays showed that the isolated capsaicinoids significantly reduced the radical length of Lactuca sativa seedling, this inhibition being dose-dependent.     

Evaluation of the antioxidant and antibacterial properties of ethanol extracts from berries,leaves and stems of Hedera pastuchovii Woron. ex Grossh

This study was designed to examine the total phenolic and flavonoid contents, radical scavenging and antibacterial activity of the ethanolic extracts from leaves, berries and stems of Hedera pastuchovii Woron. ex Grossh. The berry extract, which contained the highest phenolic and flavonoid compounds, showed an appreciable DPPH^√ scavenging ability in comparison with leaf and stem extracts. The various extracts exhibited moderate to good activity against both Gram-negative and Gram-positive bacteria, and the effectiveness of leaf extract was higher for all tested bacteria.     

A new triterpenoid saponin from the leaves and stems of Panax quinquefolium L.

One new triterpenoid saponin,quinquenoside L_(17)(1),was isolated from the leaves and stems of Panax quinquefolium L.,and its structure was elucidated as 20-O-[(β-D-xylopyranosyl-(1-6)-O-β-D-glucopyranosyl)]-6-O-β-D-glucopyranosyl-dammar-24-ene- 3,6,12,20-tetraol,by the combination analysis of one-dimensional NMR and two-dimensional NMR,mass spectrometry,CD spectrum and chemical evidences.     

Activity antifungal of the essential oils; aqueous and ethanol extracts from Citrus aurantium L.

Our study is about the essential oil of Citrus aurantium L. in Tunisia and its plant extract. The yield of this essential oil is 0, 56% but the yield of the extract of plant was 17.1% for the aqueous extract ant 18.3% for the ethanolic extract. The analysis of chemical composition by using GC and GC/MS showed the essential oil of C. aurantium L. species to be rich in monoterpenes such as α-terpineol, lianolyl acetate, linalool and limonene. The antifungal activity of this oil showed us an inhibition of the germination of mushrooms, in the same way we could note that the biologic activities are generally assigned to the chemotypes high content in oxygenated monoterpene.     

A new ocotillol-type ginsenoside from stems and leaves of Panax quinquefolium L. and its anti-oxidative effect on hydrogen peroxide exposed A549 cells

Abstract

A new ocotillol-type ginsenoside, namely 12-one-pseudoginsenoside F₁₁ (12-one-PF₁₁), was isolated from stems and leaves of Panax quinquefolium, whose structure was elucidated 6-O-[α-L-rhamnopyranosyl-(1-2)-β-D-glucopyranosyl]-dammar-12-one-20S,24R-epoxy-3β,6α,25-triol. 12-one-PF₁₁ significantly suppressed hydrogen peroxide induced oxidative stress in human lung carcinoma A549 cells. As compared with model group, 12-one-PF₁₁ improved cell viability of A549 cells in a dose-dependent manner, and significantly decreased the generation of malondialdehyde (MDA) and increased production of superoxide dismutase (SOD) and glutathione (GSH) and protein expression levels of nuclear related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) in A549 cells.     

Study on essential oils from the leaves of two Vietnamese plants: Jasminum subtriplinerve C.L. Blume and Vitex quinata (Lour) F.N. Williams

The essential oil constituents of the leaves of Jasminum subtriplinerve (Oleaceae) and Vitex quinata (Verbanaceae) cultivated in Vietnam were analysed by gas chromatography – flame ionisation detector (GC–FID) and gas chromatography – mass spectrometry (GC–MS) techniques. The main constituents identified in J. subtriplinerve were mainly oxygenated monoterpenes represented by linalool (44.2%), α-terpineol (15.5%), geraniol (19.4%) and cis-linalool oxide (8.8%). The quantitative significant components of V. quinata were terpene hydrocarbons comprising of β-pinene (30.1%), β-caryophyllene (26.9%) and β-elemene (7.4%). The chemical compositions of the essential oils are being reported for the first time.     

Densities and compressibilities of aqueous HCl and NaOH from 0 to 45°C. The effect of pressure on the ionization of water

The densities and sound speeds of aqueous HCl and NaOH solutions were measured from 0.1 to 1.0m and from 0 to 45°C. These data were combined with literature data and fitted to functions of molality and temperature. The apparent molal volumes V and compressibilities K of these solutions were fitted to functions of molality and temperature. The partial molal volumes and compressibilities of HCl and NaOH solutions were used to calculate the partial molal volume V and compressibility changes for the ionization of water. Combined with literature data these values of V adn were used to calculated the effect of pressure on the ionization constant of water K _w from 0 to 200°C. The effect of pressure on K _w calculated from partial molal quantities are in reasonable agreement with that determined directly from high pressure measurements taken from the literature up to 1000 bar. It is necessary to use the pressure dependence of K ⁰ to extend the calculated pressure dependence of K _w up to 6000 bar.     

Effects of Extraction Technique on the Content and Antioxidant Activity of Flavonoids from Gossypium Hirsutum linn. Flowers

Cotton is one of the Uyghur medical materials in China and is rich in flavonoids. Flavonoids have important pharmacological effects. The yield of flavonoids in traditional extraction methods is low, which affects the development of flavonoids. Therefore, it is urgent to optimize the extraction techniques. The yield of flavonoids in cotton flowers was effectively improved by response surface methodology, and the highest yield of flavonoids reached 5.66%, and the optimal extraction process conditions were obtained. The DPPH free radical scavenging rate, hydroxyl free radical scavenging rate, superoxide anion free radical scavenging rate, and reducing ability were tested to reflect the antioxidant capacity of flavonoids. The flavonoids had an excellent antioxidant effect. Cell experiments suggested that the flavonoids had the effect of protecting glutamate-induced damage to HT-22 cells. The results of this study provide a theoretical basis for the extraction of cotton flowers flavonoids and the comprehensive evaluation of antioxidant products, as well as the extraction of other plant flavonoids.     

Spleen and thymus metabolomics strategy to explore the immunoregulatory mechanism of total withanolides from the leaves of Datura metel L. on imiquimod-induced psoriatic skin dermatitis in mice

Our previous work demonstrated that total withanolides of Datura metel L. leaves (TWD) exhibited excellent therapeutic effects on psoriasis. However, current knowledge of its mechanisms is incomplete. In this study, integrated spleen and thymus untargeted metabolomics were used to analyze the changes in endogenous metabolites underlying the immunosuppressive activity of TWD on psoriasis animal models induced by imiquimod. The results suggested that TWD treatment markedly attenuated imiquimod-induced psoriasis and showed significant immunosuppressive activity as evidenced by decreased elevation index of spleen and thymus. Meanwhile, TWD significantly reversed the elevation of immunoregulatory factors, including IL-10, IL-17, IL-22 and IL-23. Multivariate trajectory analysis revealed that TWD treatment could restore the psoriasis-disturbed spleen and thymus metabolite profiles towards the normal metabolic status. A total of 25 and 27 metabolites associated with the immunomodulatory effects for which levels changed markedly upon treatment have been identified in spleen and thymus, respectively. These differential metabolites were mainly involved in amino acid metabolism, nucleotide metabolism, fatty acid metabolism and lipid metabolism. Our investigation provided a holistic view of TWD for intervention in psoriasis through immunoregulation and provided further scientific information in vivo about a clinical value of TWD for psoriasis.     

New Bisabolane Sesquiterpenes from the Rhizomes of Curcuma xanthorrhiza Roxb. and Their Inhibitory Effects on UVB‐Induced MMP‐1 Expression in Human Keratinocytes

Two new bisabolane sesquiterpenoids, 1 and 2 , along with five known ones, 13‐hydroxyxanthorrhizol ( 3 ), 12,13‐epoxyxanthorrhizol ( 4 ), xanthorrhizol ( 5 ), β‐curcumene ( 6 ), and β‐bisabolol ( 7 ), were isolated from the rhizomes of Curcuma xanthorrhiza Roxb . The chemical structures of the new compounds were determined to be (7R,10R)‐10,11‐dihydro‐10,11‐dihydroxyxanthorrhizol 3‐O‐β‐D ‐glucopyranoside ( 1 ) and (?)‐curcuhydroquinone 2,5‐di‐O‐β‐D ‐glucopyranoside ( 2 ) on the basis of 1D‐ and 2D‐NMR spectroscopic analyses and optical‐rotation characteristics. Compounds 2 and 3 decreased MMP‐1 expression in UVB‐treated human keratinocytes by ca. 8.9‐ and 7.6‐fold at the mRNA level, and by ca. 9.2‐ and 6.6‐fold at the protein level, respectively. The results indicate that the isolated compounds may have anti‐aging effects through inhibition of MMP‐1 expression in skin cells.     

Formation of 3-Bromo-1,5- and −1,7-Azulenequinones from 1-Alkyl-and 1-Phenylazulenes by Substituent Extrusion on the Bromine- Oxidation in Aqueous THF. Remarkable Substituent Effects on the Product Distribution

Oxidation of 1-ethyl-, 1-propylazulenes, and their 5-isopropyl derivatives with bromine gave 3-bromo-1,5- and 3-bromo-l,7-azulenequinones (Type A) together with 3-bromo-l-hydroxy-5-isopropyl-l-alkylazulen-7-one and its isomeric products (Type B), while the same reaction of 1-methylazulenes afforded Type B products along with many unidentified products. On the other hand, 1-phenylazulene gave 3-phenyl-1,5- and 3-phenyl-l,7-azulenequinones (Type C) and Type B products in high yie]ds. 1,2-Polymethyleneazulenes afforded a considerable amount of 3-bromo-2-(ω-formylalkyl)azulenequinones together with Type B products. Possible pathways for the extrusion of the alkyl substituent at C-l are discussed.