Potential influence of the chemical composition of water on the stable oxygen isotope composition of continental ostracods

Many studies in continental areas have successfully used the oxygen isotope composition of fossil ostracod valves to reconstruct past hydrological conditions associated with large changes in climate. Yet, ostracods are known to crystallise their valves out of isotopic equilibrium for oxygen and they generally have higher 18O contents compared to inorganic calcite grown at equilibrium under the same condi- tions. A review of vital offsets determined for continental ostracods indicates that vital offsets might change from site to site, questioning a potential influence of environmental conditions on oxygen isotope fractionation in ostracods. Results from the literature suggest that pH has no influence on ostracod vital offset. A re-evaluation of results from Li and Liu (J Paleolimnol 43:111-120, 2010) suggests that salin- ity may influence oxygen isotope fractionation in ostracods, with lower vital offsets for higher salinities. Such a relationship was also observed for the vital offsets determined by Chivas et al. (The ostracoda- applications in quaternary research. American Geo- physical Union, Washington, DC, 2002). Yet, when results of all studies are compiled, the correlation between vital offsets and salinity is low while the correlation between vital offsets and host water Mg/Ca is higher, suggesting that ionic composition of water and/or relative abundance of major ions may also control oxygen isotope fractionation in ostracods. Lack of data on host water ionic composition for the different studies precludes more detailed examination at this stage. Further studies such as natural or laboratory cultures done under strictly controlled conditions are needed to better understand the potential influence of varying environmental condi- tions on oxygen isotope compositions of ostracod valves.

Chemical composition of the small coastal lagoons of the Mediterranean Spanish littoral

About sixty small water bodies (coastal lagoons, marshes, salt pans, channels, springs, etc.) of the Spanish Mediterranean coast were sampled seasonally for one year (1979-1980), in order to study different aspects of their chemical composition. The concentrations of major ions (alkalinity, Cl-, Ca2+, Mg2+, Na+, and K+), nutrients (N.NO-3, N.NO2-, TRP and Si), oxygen and pH were determined for this purpose. The salt concentrations measured range between 0.4 and 361.3 g l-1. The samples have been divided into four classes of salinity (in g l-1): Cl, S < 5; C2, 5 40. Within these classes, the pattern of ionic dominance recorded is remarkably constant and similar to that found in most coastal lagoons (Cl- > So42- > Alk., for the anions, and Na+ > Mg2+ > Ca2+ > K+, for the cations), although other models occur especially in the first class. The dominance of Na+ and Cl-, as well as the molar ratios Mg2+/Ca2+ and Cl- / SO42- ,clearly increase from class Cl to class C4. The hyperhaline waters include different subtypes of the major brine type"c",, of EUGSTER & HARDIE (1978), the Na+ - (Mg2+) - Cl- - (SO42-) being the most frequent. Nutrient concentrations fall within a wide range (N.NO3 from 0.1 to 1100 mg-at 1-1; PRT from 0.01 to 23.56 mg-at l-1 and Si from 1.0 to 502.0 mg-at l-1). The oxygen values are very variable too, ranging between 0 and 14.4 ml l-1. Four different patterns of nutrient distribution have been distinguished based on the mean concentrations of N.NO3-, and TRP (mean values in mg-at l-1): A, N.NO3- < 10, TRP > l ; B, N.NO3- > 100, TRP < 1; C, 10 < N.NO3- < 100, TRP < 1; C, D, N.NO3- < 10, TRP < 1. As a rule, lagoons of low salinity (C1 and C2 classes) display the nutrient pattern C, and lagoons of high salinity (C3 and C4) show the nutrient pattern D. Model A only appears in waters of very low salinity, whereas model B does not seem to be related to salinity.

Changes in the isoflavone profile and in the chemical composition of tempeh during processing and refrigeration

The objective of this work was to analyze changes in the isoflavone profile, determined by high performance liquid chromatography, at different processing stages and after refrigeration of tempeh. For tempeh production, clean soybean grains from cultivars BR 36 (low isoflavone content) and IAS 5 (high) were dehulled, and the separated cotyledons were hydrated and then cooked in boiling water for 30 min. Spores of the fungus Rhizopus microsporus var. oligosporus were inoculated in the cooked and cooled cotyledons, and incubated at 32ºC for 6, 12, 18, and 24 hours in perforated polypropylene bags, for fermentation. The resulting tempeh was stored at 4ºC for 6, 12, 18, and 24 hours. After 24-hour fermentation, isoflavone glucosides were 50% reduced, and the aglycone forms in the tempeh from both cultivars was increased. The malonyl forms reduced 83% after cooking. Less than 24 hours of refrigeration did not affect the isoflavone profile of tempeh from either cultivar, which is a good indicator of its quality. The tempeh maintains the high and low isoflavone content of the cultivars, which indicates that cultivar differences in this trait should be considered when processing tempeh.

Adaptability and stability of white oat cultivars in relation to chemical composition of the caryopsis

The objective of this work was to characterize the chemical properties of white oat (Avena sativa) caryopsis and to determine the adaptability and stability of cultivars recommended for cultivation in the state of Rio Grande do Sul, Brazil. The trials were carried out in the 2007, 2008 and 2009 crop seasons, in three municipalities: Augusto Pestana, Capão do Leão, and Passo Fundo. Fifteen cultivars were evaluated in a randomized block design, with four replicates. The contents of protein, lipid, and nitrogen-free extract were evaluated in the caryopsis. Cultivar performances for the measured characters varied according to location and year of cultivation. The cultivar URS Guapa showed high content of nitrogen-free extract and low contents of protein and lipid in the caryopsis. 'FAPA Louise' showed high content of lipid, whereas 'Albasul', 'UPF 15', and 'UPF 18' showed high content of protein and low content of nitrogen-free extract. There is no evidence of an ideal biotype for the evaluated characters, which could simultaneously show high average performance, adaptability to favorable and unfavorable environments, and stability.

Chemical composition and fatty acid contents in farmed freshwater prawns

The objective of this work was to evaluate the chemical composition and fatty acid contents of Amazonian and giant river prawns. After four-month farming, with the same diet for both species, palmitic and stearic acids were the main saturated fatty acids. Oleic acid was the main monounsatured fatty acid, and the eicosapentaenoic and docosahexaenoic acids were the most abundant polyunsaturated acids. Amazonian prawn has higher levels of protein and polyunsaturated fatty acids than those of the giant river prawn, which shows its potential for aquaculture.

Effects of DMPP on the growth and chemical composition of ryegrass (Lolium perenne L.) raised on calcareous soil

Se llevó a cabo un experimento de 406 días en macetas para evaluar el nuevo inhibidor de la nitrificación, 3,4-dimetilpirazol fosfato (DMPP), añadido a purines de cerdo. Se utilizaron macetas que contenían tierra franca calcárea que fueron sujetas a los siguientes tratamientos: sin purín, 73,7; 147,3 y 221 cm3 de purín por maceta, todas con o sin tratamiento de DMPP. A los 18 días las macetas fueron sembradas con Lolium perenne L. El mayor rendimiento (36,3 g maceta-1) se obtuvo para el tratamiento con la dosis superior de purín y DMPP, siendo un 7,4% superior al mismo tratamiento sin inhibidor y un 46,1% superior al tratamiento control. Las plantas tratadas con dosis alta y mediana, más el DMPP, absorbieron el 70% del total del N durante la primera fase del experimento (104 días) mientras que sin inhibidor absorbieron el 55,3 y el 62% respectivamente. Se observó una reducción significativa del 17% en el N lixiviado en los tratamientos sin cultivo al aplicar DMPP. El inhibidor aumentó significativamente la eficiencia agronómica del purín (g materia seca g-1 N aplicado).

Characterization of the chemical composition of the essential oils from Annona emarginata (Schltdl.) H. Rainer 'terra-fria' and Annona squamosa L.

The objective of this study was to characterize the chemical composition of the essential oil from the leaves of Annona emarginata (Schltdl.) H. Rainer 'terra-fria' and Annona squamosa L. The species were grown in a greenhouse for 18 months, which nutrient solution was applied weekly; the plants were then harvested and the leaves dried to extract the essential oil. The essential oil was analyzed by gas chromatography and mass spectrometry to study its chemical profiles. Eleven substances were found in the essential oil of A. emarginata, primarily (E)-caryophyllene (29.29%), (Z)-caryophyllene (16.86%), γ-muurolene (7.54%), α-pinene (13.86%), and tricyclene (10.04%). Ten substances were detected in the oil from A. squamosa, primarily (E)-caryophyllene (28.71%), (Z)-caryophyllene (14.46%), α-humulene (4.41%), camphene (18.10%), α-pinene (7.37%), β-pinene (8.71%), and longifolene (5.64%). Six substances were common to both species: (E)-caryophyllene, (Z)-caryophyllene, α-humulene, camphene, α-pinene, and β-pinene.

Chemical composition of umbu (Spondias tuberosa Arr. Cam) seeds

The umbu tree (Spondias tuberosa Arr. Cam) is an important fruit tree the economy of the semi-arid northeastern region of Brazil. With the objective of finding use for the seeds, physical and chemical characterizations of the seeds from 2 cultivars in 2 maturation stages were carried out and their fatty acid and mineral profiles determined. The results showed no differences between the seeds analyzed. The yield was about 10% and the dimensions as follows: length from 1.48 to 2.11 cm and width from 0.76 to 1.16 cm. The average lipid content was 55% of which 69% was unsaturated and the average protein content was 24%. The seeds were a good source of the following minerals: P, K, Mg, Fe and Cu. The overall results indicated that the oil or the seeds could be used for food stuffs if no toxic agents were found.

Evaluation of seasonal changes in chemical composition and antibacterial activity of Elyonurus muticus (sprengel) O. Kuntze (Gramineae)

Aerial parts of Elyonurus muticus were collected in the four seasons of the year in the Brazilian Pantanal and subjected to extractrion with cold ethanol and to hydrodistillation. Sesquiterpenoids (E)-caryophyllene, bicyclogermacrene, spathulenol and caryophyllene oxide were the main components identified in the essential oils and their concentrations varied according to the plant collection period. The essential oils and the ethanolic crude extracts were active against Bacillus cereus MIP 96016, Pseudomonas aeruginosa ATCC 27853 and Staphylococcus aureus ATCC 25923 and were not active against Escherichia coli ATCC 25922. The antibacterial activities varied according to the plant collection period.

Chemical composition and antimicrobial activity of the essential oil from Aeolanthus suaveolens Mart. ex Spreng

The essential oils from leaves (sample A) and flowers (sample B) of Aeolanthus suaveolens Mart. ex Spreng were obtained by hydrodistillation and analyzed by GC, GC-MS, and chiral phase gas chromatography (CPGC). Six compounds have been identified from the essential oils, representing ca 94.3 and 93% of the oils corresponding to samples A and B, respectively. The major constituents of samples A and B essential oils were respectively, linalool (34.2%/34.9%), (-)-massoialactone (25.9%/17.0%) and (E)-beta-farnesene (25.4%/29.1%). The enantiomeric distribution of the monoterpene linalool was established by analysis on heptakis- (6-O-methyl-2,3-di-O-pentyl)-beta-cyclodextrin capillary column. The antimicrobial activity of the essential oil from leaves and isolated compounds was also evaluated.

Chemical composition and antimicrobial activity of the essential oil of Hyptis pectinata (l.) Poit.

Essential oil was extracted from leaves of Hyptis pectinata using hydrodistillation, and its composition determined using GC-FID and GC-MS. Chemical analysis showed that there was a predominance of sesquiterpenes, of which β-caryophyllene (18.34%), caryophyllene oxide (18.00%) and calamusenone (24.68%) were measured for the first time in the genus Hyptis. Twenty-one compounds were identified, and calamusenone was isolated using preparative thin layer chromatography with a silica gel plate (60 PF254). The minimal inhibitory concentration (MIC) and minimal microbicidal concentration (MMC) were determined for various pathogenic microorganisms. H. pectinata oil was most effective against Gram (+) bacteria and yeasts.

Chemical composition and analgesic activity of the leaves and branches of Marlierea tomentosa Camb.

This paper describes the isolation of five phytoconstituents from Marlierea tomentosa. The triterpenes α-amyrin (1) and β-amyrin (2), and the flavonoids quercitrin (3) and isoquercetin (4), were isolated from the leaves. The branches afforded the triterpene arjunolic acid (5). The antinociceptive activity of crude extract, fractions and compound 5 were tested using the writhing and formalin tests in mice. The crude extract, some fractions, particularly dichloromethane and butanol (leaves), ethyl acetate (branches) and arjunolic acid (5) (81.2% inhibition) were more active against the writhing test than the two reference drugs, acetylsalicylic acid and indomethacin.

Chemical composition and antibacterial activities from the essential oils of myrtaceae species planted in Brazil

The essential oils of seven Myrtaceae species were investigated for its chemical composition and antibacterial activity. The volatile oils were characterized by a high content of monoterpenoids of which 1,8-cineole (88.0, 65.0 and 77.0% for Melaleuca hypericifolia, Callistemon viminalis and Callistemon citrinus respectively), terpinen-4-ol (47.0 and 49.8% for Melaleuca thymifolia and Callistemon polandii respectively) and α-pinene (54.5% for Kunzea ericoides) were the major components. The oil from M. linariifolia was characterized by a high concentration of methyleugenol (87.2%). The oil from Melaleuca thymifolia was the most active, exhibiting high antimicrobial activity against all tested bacteria.

Chemical composition of volatile oils from leaves of Nectandra megapotamica Spreng. (Lauraceae)

The volatile oils from Nectandra megapotamica Spreng. leaves, collected in February and August of 2007 and at 7:00 and 12:00 h (samples A - D), were extracted by hydrodistillation and the chemical composition was analyzed by GC-FID and GC/MS. A total of nineteen compounds were identified with predominance of oxygenated sesquiterpenes, among them, α-bisabolol, was the main constituent (62.3-69.4 %). After chromatographic separation procedures, this compound was purified from crude oil and its structure was confirmed by analysis of NMR data. This paper describes for the first time the composition of the leaves volatile oil from N. megapotamica.

Chemical composition and antibacterial activity of essential oils from verbenaceae species: alternative sources of (E)-caryophyllene and germacrene-D

Volatile oils from the leaves of Verbenaceae species Aloysia virgata, Lantana camara, Lantana trifolia, Lantana montevidensis, Lippia brasiliensis and Lippia sericea were investigated for its chemical composition and antibacterial activity. The volatile oils were characterized by a high content of sesquiterpenes of which (E)-caryophyllene (10-35%), germacrene-D (5-46%) and bicyclogermacrene (7-17%) were the major components for all studied species. For the flowers, a higher concentration of monoterpenes was observed for the species L. camara, L. trifolia and L. brasiliensis. These compounds probably act as attractive to specific pollinators. The volatile oils from A. virgata was the most active, exhibiting moderate antimicrobial activity against the bacteria Staphylococcus aureus, Bacillus cereus and Escherichia coli.