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temperature; solar radiation; Heliconia; fluorescence; tropics; photoinhibition; shade; photosystem II; chemical constituents of plants; chlorophyll; leaves; Singapore
Abstract:
... The influence of irradiance on photosynthesis under natural conditions was studied in aseasonal Singapore using three Heliconia taxa: H. rostrata , H. psittacorum x H. spathocircinata cv. Golden Torch and H. psittacorum cv. Tay. When grown under full sunlight, all three heliconias exhibited reduced photosynthetic capacities and lowered chlorophyll content per leaf area as compared with those grown ...
total soluble solids; crop yield; food composition; strawberries; fruit quality; titratable acidity; cultivar identification; organic production; harvest date; weight; cultivars; research projects; firmness; photoperiod; USDA; germplasm releases; Fragaria ananassa; genetic variation; color; chemical constituents of plants; pedigree; Oregon; British Columbia
Abstract:
... 'Valley Red' is a new June-bearing (short day) strawberry cultivar from the U.S. Department of Agriculture-Agricultural Research Service breeding programme in Corvallis, Oregon, released in cooperation with the Oregon Agricultural Experiment Station, The Washington State University Agricultural Research Centre, and Agriculture and Agri-Foods Canada. 'Valley Red' was selected in 1996 from the cross ...
sesquiterpenoids; monoterpenoids; essential oils; chemical constituents of plants; Tanacetum vulgare; phenolic compounds; India
Abstract:
... The essential oil from the aerial parts of Tanacetum vulgare L. was analyzed using GC/MS. Of the 20 constituents identified, six were monoterpene hydrocarbons (3.9%), 10 oxygenated monoterpenes (81.9%), one sesquiterpene hydrocarbon (1.7%), two phenolic compounds (3.0%) and a long chain hydrocarbon (1.5%). The oil belongs to the thujone (66.8%) chemotype. (+)-10 Hydroxy-3-thujone was characterized ...
... An infection-inhibiting factor (IIF) was isolated from strawberry leaves and identified as (+)-catechin. This compound inhibited the formation of infection hyphae from appressoria of Alternaria alternata, but allowed both spore germination and appressorial formation. It is a normal component of strawberry leaves, but further accumulates as the major IIF in response to inoculation with nonpathogeni ...
Sesamum indicum; seeds; furans; lignans; spectral analysis; chemical structure; biosynthesis; biochemical pathways; chemical reactions; chemical constituents of plants
Cichorium intybus; roots; leaves; sesquiterpenoid lactones; biosynthesis; bitterness; ligases; molecular weight; pH; chemical structure; enzyme activity; chemical constituents of plants
Abstract:
... The leaves and especially the roots of chicory (Cichorium intybus L.) contain high concentrations of bitter sesquiterpene lactones such as the guianolides lactupicrin, lactucin, and 8-deoxylactucin. Eudesmanolides and germacranolides are present in smalleramounts. Their postulated biosynthesis through the mevalonatefarnesyl diphosphate-germacradiene pathway has now been confirmed by the isolation ...
Pinus densiflora; Pinus thunbergii; insect attractants; synergism; insect control; biological control; chemical constituents of plants; diterpenoids; sesquiterpenoids; Monochamus alternatus
Abstract:
... A sesquiterpene and a diterpene were isolated from sound pines and identified as (+)-juniperol and (+)-pimaral, respectively. The combination of these compounds in a certain ratio induced a significant laboratory flight response by the female cerambycid beetle, Monochamus alternatus Hope. Individual compounds elicited a limited response only. ...
... Background: Acquisition of metastatic ability by prostatic cancer cells is the most lethal aspect of prostatic cancer progression. (-)-Gossypol, a polyphenolic compound present in cottonseeds, possesses anti-proliferative and proapoptotic effects in various cancer cells. Materials and Methods: In this study, the differences between MAT-LyLu, rat prostate cancer cells, with a novel isolated subline ...
infection; Solanum lycopersicum var. lycopersicum; Pseudomonas syringae pv. phaseolicola; jasmonic acid; defense mechanisms; apoptosis; malondialdehyde; protein degradation; isomers; chemical constituents of plants
Abstract:
... Tobacco infected with Pseudomonas syringae pv. phaseolicola undergoes a hypersensitive response (HR). Jasmonic acid (JA) accumulated within the developing lesion 3 to 9 h after infection and this accumulation preceded protein loss, cell death, and malondialdehyde accumulation. Accumulating JA consisted largely of the (-)-JA stereoisomer and was essentially restricted to the HR lesion. ...
Clausena anisata; essential oils; biotypes; chemical constituents of plants; methyl chavicol; Ghana
Abstract:
... In the course of our comprehensive investigation of the oils of the leaves of Clausena anisata from three West African countries, we have observed that, on the basis of its oil constituents, C. anisata can be classified into three major chemovarieties. Two of these chemovarieties have been observed in collections in Ghana, Togo and Benin. One contains mainly methyl chavicol (80-100%), and between ...
Myrtaceae; chemical composition; interspecific variation; essential oils; ocimene; chemical constituents of plants; leaves
Abstract:
... Two undescribed species of the genus Austromyrtus possess leaf essential oils rich in (E)-beta-ocimene. This compound accounts for approximately 83% of the oil in one species, the remainder of the oil being composed of mono- and sesquiterpenes in small amounts. The second species has more variation in its oil with (E)-beta-ocimene accounting for 51-80% of the oil and myrcene accounting for 0.2-35. ...
Basidiomycota; chemical structure; spectral analysis; biosynthesis; chemical reactions; biochemical pathways; antineoplastic agents; chemical constituents of plants; sesquiterpenoids
Actinidia chinensis; kiwifruit; ripening; chemical constituents of plants; esters; volatile organic compounds; cold storage; ethylene production; gene expression regulation
Abstract:
... Four 3-(methylsulfanyl)propionate esters, ethyl 3-(methylsulfanyl)prop-2-enoate, two 2-(methylsulfanyl)acetate esters and their possible precursors 2-(methylsulfanyl)ethanol, 3-(methylsulfanyl)propanol and 3-(methylsulfanyl)propanal were quantified from the headspace of Actinidia chinensis ‘Hort 16A’ kiwifruit pulp by GC–MS–TOF analysis. The majority of these compounds were specific for eating-rip ...
Polygalaceae; seed oils; lactones; chemical constituents of plants; mass spectrometry; ozone; chemical structure; nuclear magnetic resonance spectroscopy; optics
Sesbania bispinosa; seed oils; fatty acid composition; chemical structure; industrial oils; fatty acids; spectral analysis; chemical constituents of plants
Abstract:
... On the basis of various industrial importances of hydroxyl fatty acids we have investigated Sesbania aculeata seed oil. The most interesting finding is the presence of a hydroxyolefinic fatty acid (9.24%) along with other usual fatty acids such as lauric (2.51%), myristic (0.37%), palmitic (10.94%), palmitoleic (3.54%), stearic (4.02%), oleic (17.10%), linoleic (45.92%), linolenic (5.29%), arachid ...
Myrtaceae; interspecific variation; essential oils; ocimene; chemical constituents of plants; yields; Australia
Abstract:
... (Z)-beta-ocimene has been found to occur in amounts of 85% in foliage of Homoranthus montanus Craven and S. R. Jones and 69-71% in H. flavescens Cunn. ex. Schauer. (E)-beta-ocimene also occurred in amounts of 5-9% and 2-5% respectively. The oil yield in both cases was 0.3-0.5% based on fresh leaves. ...
Rubiaceae; stems; alkaloids; spectral analysis; chemical structure; antineoplastic agents; humans; cell lines; medicinal properties; chemical constituents of plants; Panama
... Natural lipids and oils are subject to oxidative degradation affecting color, odor, viscosity, and lubricity, which lowers the quality of the commercial products containing these lipids. In the food, cosmetics and pharmaceutical industries, maintaining high quality color and odor of oils and other lipids is important. Meadowfoam (Limnanthes alba) seed oil is more oxidatively stable than other vege ...
Kyllinga; aerial parts; rhizomes; chemical constituents of plants; essential oils; beta-caryophyllene; quantitative analysis; chemotypes
Abstract:
... The investigation of the essential oils of the aerial part and rhizomes of Kyllinga erecta by capillary gas chromatography (GC) and gas chromatography/mass spectrometry (GC/MS) led to the identification of 31 and 49 compounds respectively. The oil of the aerial parts had 1,8-cineole (10.5%), α-humulene (21.7%), farnesyl acetate (11.2%), β-caryophyllene (9.9%) and selin-11-en-4-ol (8.9%) as the maj ...
pyrrolizidine alkaloids; Fabaceae; spectral analysis; chemical constituents of plants; chemical structure; stereochemistry
Abstract:
... A new pyrrolizidine alkaloid [6a] has been isolated from the legume Castanospermum australe A. Cunn. (Leguminosae) and identified as (1S, 2R, 3R, 7S, 7aR)-3-hydroxymethyl-1,2,7-trihydroxypyrrolizidine on the basis of 1H NMR nuclear Overhauser effects and other spectroscopic studies. ...
coleoptiles; Zea mays; metabolism; dose response; glucose; seedlings; enzyme inhibitors; endosperm; naphthaleneacetic acid; chemical constituents of plants; protein content; catalytic activity; transferases; mesocotyls; indole acetic acid; cycloheximide
Abstract:
... The enzyme indole-3-acetylglucose synthase (UDPG: indole-3-ylacetyl glucosyl transferase) catalyzes the reaction: UDPG + IAA [reversible reaction] 1-O-IAGlc + UDP. The enzyme is abundantly present in immature maize endosperm, but present in lesser amount in the endosperm of germinating kernels. Rabbit polyclonal antibodies, against purified IAGlc synthase, easily visualize the presence of the enzy ...
Piperaceae; essential oils; leaves; chemical constituents of plants
Abstract:
... Leaves from Ottonia anisum submitted to steam distillation yielded an oil which contains 1-butyl-3,4-methylenedioxybenzene as the major component (about 95%). GC/MS analysis of this oil showed the presence of monoterpenes and sesquiterpenes. Spectroscopic and GC characterization of these components has been performed by comparison with literature records. They were identified as alpha-pinene, beta ...
Apiaceae; lignans; lactones; spectral analysis; chemical structure; antineoplastic agents; humans; ovarian diseases; chemical constituents of plants; Tanzania
Annona; medicinal plants; seeds; acetogenins; spectral analysis; chemical structure; secondary metabolites; mitochondria; chemical constituents of plants; electron transfer; Colombia
nuclear magnetic resonance spectroscopy; stems; aromatic compounds; nicotine; carbohydrates; chemical constituents of plants; tobacco; leaves
Abstract:
... 13C CPMAS NMR spectra were obtained of the leaf laminae and stems of cured bright and burley tobaccos. The solid phase NMR spectra of some of the most abundant tobacco components were also obtained, including cellulose, hemicellulose, and pectin (each isolated from tobacco), calcium and potassium salts of malic and citric acid, calcium oxalate, rutin, chlorogenic acid, and nicotine (in the form of ...