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91.
One‐year‐old rooted cuttings of Vitis vinifera L. cv. “Pinot blanc”; grafted on “Kober 5BB”; hybrid rootstock were grown in pots containing a calcareous soil. Before potting, the roots were treated by a suspension of the siderophore producing bacteria Pseudomonas fluorescens, other Pseudomonas spp., and some unidentified microorganisms. The tested bacteria were endophytic microorganisms from maize and they were chosen according to their ability to produce fluorescent pigments. The shoot growth was checked every ten days, and leaf blades, sampled about 80 days after bud burst, were analyzed for chlorophyll and mineral element concentration. Chlorosis rating was checked by visual screening in order to control the effect of the treatments on the chlorosis. At the end of the growing cycle dry matter and iron (Fe) partitioning were analyzed. The most significant findings of the trial were: a) the tested microorganisms did not improve significantly lime‐tolerance of the tested plants; b) the microorganisms were able to modify phosphorus (P), potassium (K), and Fe mineral nutrition of the vines. 相似文献
92.
Calzuola I Marsili V Gianfranceschi GL 《Journal of agricultural and food chemistry》2004,52(16):5201-5206
Aqueous and ethanolic extracts from wheat (Triticum aestivum) sprout powder were analyzed to determine its reduction and antioxidant activities. Mean and standard deviation of five independent samples were reported. The results showed that the micromoles of potassium ferricyanide reduced by aqueous and ethanolic extracts corresponding to 1 g of sprout powder (80.6 +/- 11.2 and 9.7 +/- 1.8, respectively) were higher than that reduced by 1 mg of other reducing compounds: ascorbic acid, rutin, quercetin, and reduced gluthatione (4.8 +/- 0.7, 3.8 +/- 1.2, 4.8 +/- 1.7, and 1.6 +/- 0.4, respectively). In addition, the oxygen superoxide scavenging activity performed by sprout extracts (from 1 g of powder) is comparable to that shown by 10 mg of antioxidant pure compounds (rutin and quercetin). Biochemical analysis of the sprout extracts shows that the antioxidant activity is mainly due to reducing glycoside and polyphenolic compounds. 相似文献
93.
Fanali C Dugo L Cacciola F Beccaria M Grasso S Dachà M Dugo P Mondello L 《Journal of agricultural and food chemistry》2011,59(24):13043-13049
A chemical characterization of the major components, namely, triacylglycerols (TAGs), polyphenols, and tocopherols in a Sacha inchi oil derived from cold pressing of the seed, is hereby reported. To tackle such a task, high-performance liquid chromatography in combination with photodiode array (PDA), fluorescence (RF), and mass spectrometry (MS) detection was employed. The latter was interfaced with atmospheric pressure chemical ionization and with electrospray ionization for the analysis of TAGs and polyphenols, respectively, whereas RF detection was tested for the determination of tocopherol content. Furthermore, fatty acid methyl esters (FAMEs) were evaluated by gas chromatography-flame ionization detector. A 93% amount of total fatty acids was represented by unsaturated FAMEs with the greatest percentage represented by linoleic (L) and linolenic (Ln) accounting for approximately 50 and 36%, respectively. The main TAGs (>10%) were represented by LLnL, LnLnLn, and LnLLn; the latter was present in the oil sample at the highest percentage (22.2%). Among tocopherols, γ-tocopherol was detected to be the most abundant component (over 50%). The polyphenolic composition was also investigated, and a total of 15 compounds were positively identified, through the complementary analytical information coming from PDA and MS data. To the best of our knowledge, this is the first report providing a thorough chemical characterization of a Plukenetia volubilis L. oil. 相似文献
94.
Romano Dallai Vittoria Cavallo Luigi Federico Falso Pietro Paolo Fanciulli 《Pedobiologia》2000,44(3-4)
The fine structure of the male reproductive system of Allacma fusca (L.) is described. The system consists of testes, deferent ducts, seminal vesicles, ejaculatory duct and accessory glands. The nature of each part is established. Secretions from the seminal vesicles are stored in the lumen of these organs, then flow into the ejaculatory duct and are used to produce spermatophores. The epithelium of this tract has secretory activity and osmoregulatory function. Secretions and spermatozoa are stored into two distinct parts of the ejaculatory duct, divided by a transverse cuticular septum. 相似文献
95.
The ability of four commercial preparations of Oenococcus oeni lactic acid bacteria (EQ 54, Lalvin OSU, Uvaferm Alpha, and Lalvin 31) to hydrolyze wine aroma precursors was evaluated by measuring the concentration of free and bound aroma compounds at the end of malolactic fermentation carried out in model wines containing a mixture of glycosides extracted from Muscat wine. At pH 3.4 there was a decrease in glycosylated compounds matched by a concomitant increase in free forms in all starter cultures tested. When malolactic fermentation was carried out at pH 3.2, a significant decrease in the ability to hydrolyze aroma precursors was observed for two of the cultures tested (Uvaferm Alpha and Lalvin 31). Large differences in the extent of hydrolysis and in the specificity of this activity toward specific aroma precursors were observed and appeared to be related to the chemical structure of the aglycon as well as to individual characteristics of each starter culture. The amounts of glycosylated aroma compounds released during malolactic fermentation suggest that O. oeni can alter the sensory characteristics of wine through the hydrolysis of aroma precursors. 相似文献
96.
Francesco Pini Cristina Grossi Sabrina Nereo Luigi Michaud Angelina Lo Giudice Vivia Bruni Franco Baldi Renato Fani 《European Journal of Soil Biology》2007,43(5-6):368
A set of 21 Antarctic marine bacteria isolated from the Ross Sea and able to utilise diesel fuel as the sole carbon and energy source was characterised. Isolates were analysed by amplified 16S rDNA restriction analysis using the enzyme AluI, resulting in two different groups corresponding to different bacterial species. These species were assigned to the genera Rhodococcus and Alcaligenes, on the basis of 16S rDNA sequencing. This low degree of inter-specific biodiversity was parallel to a low intra-specific biodiversity, as shown by Random Amplified Polymorphic DNA analysis. Then, a 550-bp DNA fragment coding for the inner region of alkane mono-oxygenase was PCR-amplified from the genome of each strain. The phylogenetic analysis of the sequence of the putative AlkB protein coded for by the amplified DNA fragment revealed that these alkB genes were very likely inherited by horizontal gene transfer. Lastly, the analysis of the biodegradation ability of four strains revealed two different strategies of hydrocarbon uptake, mediated either by bio-surfactants and peculiar of Rhodococcus isolates, or by membrane modifications and shown by Alcaligenes isolates. In order to understand the interrelationships between hydrocarbon-degrading isolates, the dynamics of two strains, belonging to Rhodococcus and Alcaligenes, grown together in a co-culture was also followed over a seventeen days period. 相似文献
97.
Andreakis N Giordano I Pentangelo A Fogliano V Graziani G Monti LM Rao R 《Journal of agricultural and food chemistry》2004,52(11):3366-3371
Twenty-five landraces of the cherry-like tomato named Corbarino, a typical niche product grown in the Sarno valley of the Campania region, have been characterized. The landraces used have been compared to eight cultivars widely spread in the same area of cultivation. The genetic diversity within and between landraces was evaluated through the comparison of DNA fingerprints obtained with (GATA)(4) probe hybridized to TaqI digested genomic DNA. Twenty-two of the Corbarino landraces were homogeneous and were unequivocally characterized by their DNA fingerprints. The others are probably "population varieties" in that within each of them polymorphic DNA fragments were identified. According to the characterization of fruit shapes, four groups were identified. One landrace from each group, harvested at the same ripening degree, was further characterized for yield, fruit quality components, antioxidant activities, and carotenoid contents and compared to Faino F(1) and Tomito F(1) hybrids. The Corbarino landraces were all characterized by high yield, a high level of carbohydrates, and high levels of soluble and total solids. Interestingly, the biotype named ISCI 05 was the most suitable for canning. Landraces ISCI 07 and ISCI 05 gave the highest value of antioxidant activities and carotenoid content. These data, together with previously published results, suggested that ISCI 05 should be proposed for the institution of a Label of Origin. 相似文献
98.
Angioni A Dedola F Garau VL Schirra M Caboni P 《Journal of agricultural and food chemistry》2011,59(12):6806-6812
The behavior in field and the transfer from grapes to wine during winemaking of iprovalicarb, indoxacarb, and boscalid was studied. The residue levels found in grapes were far below the MRLs set for grapes in EU, accounting at harvest time 0.81, 0.43, and 4.23 mg/kg for iprovalicarb, indoxacarb, and boscalid, respectively. The residue levels in the samples treated with boscalid may have residual problems (due to an accumulation effect) if repeated field treatments will be performed. Winemaking experiments showed a complete transfer of all pesticide from grapes to the must, while in wine the residues were low or negligible due to the adsorbing effect of lees and pomace. The clarification experiments showed a good removal of pesticide residues from the wine media, for all pesticides. The GC-ITMS method showed good performance with adequate recoveries ranging from 75 to 115%, and good method limits of quantitation (LOQs) and of determination (LODs) far below MRLs. 相似文献
99.
Servillo L Giovane A Balestrieri ML Bata-Csere A Cautela D Castaldo D 《Journal of agricultural and food chemistry》2011,59(17):9410-9416
Numerous compounds, many of them osmolytes, were quantified in natural juices and in frozen concentrate juices from fruits of plants of the Citrus genus. L-proline, N-methyl-L-proline (hygric acid), N,N-dimethyl-L-proline (stachydrine), 4-hydroxy-L-prolinebetaine (betonicine), 4-hydroxy-L-proline, γ-aminobutyric acid (Gaba), 3-carboxypropyltrimethylammonium (GabaBet), N-methylnicotinic acid (trigonelline), and choline in the fruit juices of yellow orange, blood orange, lemon, mandarin, bitter orange (Citrus aurantium), chinotto (Citrus myrtifolia), and grapefruit were analyzed by sensitive HPLC-ESI-tandem mass spectrometry procedure. It was found that the most represented osmolytes in the juices, that is, L-proline, stachydrine, and betonicine, can be quantified with minimal sample preparation and short analysis time (about 1 min) also by flow injection analysis (FIA) ESI-MS/MS with the same results as obtained by HPLC ESI-MS/MS. In all of the juices, discrete amounts of choline and trigonelline were present. Conversely, GabaBet was always below detection limits. Notably, N-methyl-L-proline and 4-hydroxy-L-prolinebetaine, which were discovered for the first time in the juice of bergamot (Citrus bergamia Risso et Poit), are also present in all of the citrus juices examined. 相似文献
100.
Maroli M Pennisi MG Di Muccio T Khoury C Gradoni L Gramiccia M 《Veterinary parasitology》2007,145(3-4):357-360
Despite the recent reports of feline leishmaniosis from Southern Europe, cats are still regarded as unusual Leishmania hosts. A cat found chronically infected with Leishmania was submitted to xenodiagnosis. After being sedated, the animal was exposed to the bite of 100 laboratory-reared Phlebotomus perniciosus in a fine net cage for 90 min. Four out of 19 blood-fed sandflies (21%) showed motile promastigotes at the dissection. Parasites cultured from cat's lymph node and an infected fly were identical at PCR-RFLP genotyping and identified as Leishmania infantum MON-1, the main zymodeme responsible for human and canine leishmaniosis in Southern Europe. This is the first evidence of transmissibility of feline parasites to a proven vector, suggesting that cats may represent an additional domestic reservoir for L. infantum. 相似文献