Postharvest harpin or Bacillus thuringiensis treatments suppress citrus black spot in `Valencia` oranges

Citrus black spot (CBS) caused by Guignardia citricarpa represents an important threat to citriculture in Brazil. Limited information is available regarding potential biological control agents and new alternative compounds that may provide protection of orange fruits against the disease. In this study, the effects of commercial products based on Bacillus thuringiensis var. kurstaki (Bt) bacterium, Bt pure isolates and Harpin protein (Messenger (R)) on the postharvest control of CBS, were evaluated in `Valencia` sweet orange fruits harvested for three consecutive years in a citrus grove. The fruits were sprayed with the following products: DiPel (R) WP (Bt, subspecies, kurstaki strain HD-1,16,000 International Units mg(-1), 32 g active ingredient kg(-1)) (1, 20 and 50 mg ml(-1)), Dimy Pel (R) WP (Bt, subspecies, kurstaki, strain HD-1, 17,600 IU mg(-1), 26 g active ingredient l(-1)) (2, 20 and 50 mg ml(-1)), Messenger (R) (3% harpin protein) (1 and 2 mg ml(-1)) and fungicide Tecto (R) Flowable SC (thiabendazole, 485 gl(-1)) (0.8g active ingredient l(-1)), besides the Bt isolates, Bt- HD-567, Bt- DiPel and Bt- Dimy (9 x 10(8) CFU ml(-1)). Ten days after treatment, the number of newly developed CBS lesions and pycnidia produced were evaluated using fifty fruits per treatment. The Dimy Pel (R) and Messenger (R) reduced the number of new developed CBS lesions on fruits in up to 67% and 62%, respectively. All applied treatments drastically decreased the number of pycnidia produced in the CBS lesions on orange fruits with 85% to 96% reductions compared to the untreated control. Volatile compounds produced by the isolates Bt- HD-567, Bt- Dimy and Bt- DiPel, reduced the number of lesions on treated fruits by 70%, 65% and 71% compared to the control, respectively. In addition, the survival of Bt isolates on orange fruit surfaces were evaluated by recovering and quantifying the number of CFU every seven days for up to 28 days. The declines in survival rates on orange fruit surfaces were drastic for the three strains of Bt in the first week. The CFU numbers of all applied isolates declined by 4 to 5 orders of magnitude after storage at room temperature for 28 days. In vitro assays revealed that the Bt isolates significantly reduced the mycelial growth of the pathogen, ranging from 32% to 51%, compared to the control, whereas no inhibitory effect was observed in the presence of Messenger (R). (C) 2010 Elsevier Ltd. All rights reserved.

Lysine biosynthesis and nitrogen metabolism in quinoa (Chenopodium quinoa): Study of enzymes and nitrogen-containing compounds

Aspartate kinase (AK, EC 2.7.2.4), homoserine dehydrogenase (HSDH, EC 1.1.1.3) and dihydrodipicolinate synthase (DHDPS, EC 4.2.1.52) were isolated and partially purified from immature Chenopodium quinoa Willd seeds. Enzyme activities were studied in the presence of the aspartate-derived amino acids lysine, threonine and methionine and also the lysine analogue S-2-aminoethyl-L-cysteine (AEC), at 1 mM and 5 mM. The results confirmed the existence of, at least, two AK isoenzymes, one inhibited by lysine and the other inhibited by threonine, the latter being predominant in quinoa seeds. HSDH activity was also shown to be partially inhibited by threonine, whereas some of the activity was resistant to the inhibitory effect, indicating the presence of two isoenzymes, one resistant and another sensitive to threonine inhibition. Only one DHDPS isoenzyme highly sensitive to lysine inhibition was detected. The results suggest that the high concentration of lysine observed in quinoa seeds is possibly due to a combined effect of increased lysine, synthesis and accumulation in the soluble form and/or as protein lysine. Nitrogen assimilation was also investigated and based on nitrate content, nitrate reductase activity, amino acid distribution and ureide content, the leaves were identified as the predominant site of nitrate reduction in this plant species. The amino acid profile analysis in leaves and roots also indicated an important role of soluble glutamine as a nitrogen transporting compound. (c) 2007 Elsevier Masson SAS. All rights reserved.

Sweet Basil (Ocimum basilicum) Extracts Obtained by Supercritical Fluid Extraction (SFE): Global Yields, Chemical Composition, Antioxidant Activity, and Estimation of the Cost of Manufacturing

In this work, supercritical technology was used to obtain extracts from Ocimum basilicum (sweet basil) with CO(2) and the cosolvent H(2)O at 1, 10, and 20% (w/w). The raw material was obtained from hydroponic cultivation. The extract`s global yield isotherms, chemical compositions, antioxidant activity, and cost of manufacturing were determined. The extraction assays were done for pressures of 10 to 30 MPa at 303 to 323 K. The identification of the compounds present in the extracts was made by GC-MS and ESI-MS. The antioxidant activity of extracts was determined using the coupled reaction of beta-carotene and linolenic acid. At 1% of cosolvent, the largest global yield was obtained at 10 MPa and 303 K (2%, dry basis-d.b.); at 10% of cosolvent the largest global yield was obtained at 10 and 15 MPa (11%, d.b.), and at 20% of cosolvent the largest global yield was detected at 30 MPa and 303 K (24%, d.b.). The main components identified in the extracts were eugenol, germacrene-D, epi-alpha-cadinol, malic acid, tartaric acid, ramnose, caffeic acid, quinic acid, kaempferol, caffeoylquinic acid, and kaempferol 3-O-glucoside. Sweet basil extracts exhibited high antioxidant activity compared to beta-carotene. Three types of SFE extracts from sweet basil were produced, for which the estimated cost of manufacturing (class 5 type) varied from US$ 47.96 to US$ 1,049.58 per kilogram of dry extract.

Plant availability of phosphorus in four superphosphate fertilizers varying in water-insoluble phosphate compounds

There is concern that the use of lower quality phosphate rock can result in elevated amounts of Fe-Al-P water-insoluble compounds in fertilizers and, consequently, low agronomic effectiveness. Therefore, studies were conducted to evaluate the effect of some of these compounds on plant growth. Four commercial superphosphates varying in chemical composition (two single and two triple superphosphates) were selected for the study. Fertilizer impurities were collected as water-insoluble residues by washing each P source with deionized water. A modal analysis, based primarily on elemental chemical analysis and x-ray diffractometry, was used to estimate the chemical composition of each P source. Water-soluble monocalcium phosphate (MCP) and the water-leached fertilizer residues were prepared to give a range of fertilizers in terms of water-soluble phosphorus (WSP) (0-100% of the available P as MCP). The water-leached fractions, MCP, and the mixtures of MCP with water-leached fractions were applied to supply 40 mg available P kg(1) to a thermic Rhodic Kanhapludult with pH values of 5.2 +/- 0.05 (unlimed) and 6.4 +/- 0.08 (limed). Wheat (Triticum aestivum L.) grown in a greenhouse for 101 d served as the test crop. The requirement for WSP was source and pH dependent. At a soil pH of 5.2, the fertilizers required 73 to 95% WSP to reach the maximum dry-matter yield, while they required 60 to 86% WSP at pH 6.4. To reach 90% of the maximum yield, all superphosphate fertilizers required <50% WSP. These results show that it is not always necessary to have high water solubility as required by legislation in many countries.

Phenolic composition of South American red wines classified according to their antioxidant activity, retail price and sensory quality

In this study, 73 South American red wines (Vitis vinifera) from 5 varietals were classified based on sensory quality, retail price and antioxidant activity and characterised in relation to their phenolic composition. ORAC and DPPH assays were assessed to determine the antioxidant activity, and sensory analysis was conducted by seven professional tasters using the Wine Spirits Education Trust`s structured scales. The use of multivariate statistical techniques allowed the identification of wines with the best combination of sensory characteristics, price and antioxidant activity. The most favourable varieties were Malbec, Cabernet Sauvignon, and Syrah produced in Chile and Argentina. Conversely, Pinot Noir wines displayed the lowest sensory characteristics and antioxidant activity. These results suggest that the volatile compounds may be the main substances responsible for differentiating red wines on the basis of sensory evaluation. (C) 2011 Elsevier Ltd. All rights reserved.

Phenolic compounds and antioxidant activity of seed and skin extracts of red grape (Vitis vinifera and Vitis labrusca) pomace from Brazilian winemaking

The phenolic compounds content and antioxidant activity of seed and skin of pomace from the vinification of grape varieties widely produced in Brazil were investigated with a view to their exploitation as a potential source of natural antioxidants. There was a greater concentration of phenolic compounds in the seeds (2128 to 16,518 mg of catechin equivalents (CE)/100 g) than in the skins (660 to 1839 mg CE/100 g). The highest antioxidant activity values determined as DPPH radical-scavenging ability and ferric reducing-antioxidant power (FRAP) were found for the seeds of the Pinot Noir variety (16,925 mu mol Trolox equivalents (TE)/100 g and 21,492 mu mol Fe(2+)/100 g, respectively) and in the skin extracts of the Isabel variety (3640 mu mol TE/100 g and 4362 mu mol Fe(2+)/100 g, respectively). The skin of Cabernet Sauvignon and Primitivo varieties had the highest contents of anthocyanins (935 and 832 mg/100 g, respectively). The grape seed extracts were rich in oligomeric and polymeric flavanols. The data suggested that grape seed and skin extracts may be exploited as antioxidant agents. (C) 2011 Elsevier Ltd. All rights reserved.

Assessing the association between phenolic compounds and the antioxidant activity of Brazilian red wines using chemometrics

The objective of this study was to evaluate the association among chemical parameters, the commercial value, and the antioxidant activity of Brazilian red wines using chemometric techniques. Twenty-nine samples from five different varieties were assessed. Samples were separated into three groups using hierarchical cluster analysis: cluster 1 presented the highest antioxidant activity towards DPPH (68.51% of inhibition) and ORAC (30,918.64 mu mol Trolox Equivalents/L), followed by cluster 3 (DPPH = 59.36% of inhibition: ORAC = 25,255.02 mu mol Trolox Equivalents/L) and then cluster 2 (DPPH = 46.67% of inhibition; ORAC = 19,395.74 gmol Trolox Equivalents/L). Although the correlation between the commercial value and the antioxidant activity on DPPH and ORAC was not statistically significant (P = 0.13 and P = 0.06, respectively), cluster 1 grouped the samples with higher commercial values. Cluster analysis applied to the variables suggested that non-anthocyanin flavonoids were the main phenolic class exerting antioxidant activity on Brazilian red wines. (C) 2010 Elsevier Ltd. All rights reserved.

Bioactive compounds and antioxidant capacities of 18 non-traditional tropical fruits from Brazil

The bioactive compounds and antioxidant capacities of polyphenolic extracts of 18 fresh and dry native non-traditional fruits from Brazil were determined using ABTS, DDPH, FRAP and beta-carotene bleaching methods. The study provides an adaptation of these methods, along with an evaluation of the compounds related to antioxidant potential. The results show promising perspectives for the exploitation of non-traditional tropical fruit species with considerable levels of nutrients and antioxidant capacity. Although evaluation methods and results reported have not yet been sufficiently standardised, making comparisons difficult, our data add valuable information to current knowledge of the nutritional properties of tropical fruits, such as the considerable antioxidant capacity found for acerola - Malpighia emarginata and camu-camu - Myrciaria dubia (ABTS, DPPH and FRAP) and for puca-preto - Mouriri pusa (all methods). (C) 2010 Elsevier Ltd. All rights reserved.

Phenolic compounds in raw and cooked rice (Oryza sativa L.) and their inhibitory effect on the activity of angiotensin I-converting enzyme

Whole rice has been widely studied due to the abundance of bioactive compounds in its pericarp. Some of the beneficial effects of these compounds on human health have been attributed to their antioxidant and other biological activities, such as enzyme inhibition. In this work, we evaluated the contents of total, soluble and insoluble phenolic compounds of 6 red and 10 non-pigmented genotypes of whole rice as well as their inhibitory effect on the activity of angiotensin I-converting enzyme (ACE). The effects of cooking on phenolics and their inhibitory activities were also investigated. Red genotypes showed high content of phenolics, mainly soluble compounds, at an average of 409.7 mg ferulic acid eq./100 g, whereas overall lower average levels (99.4 mg ferulic acid eq./100 g) at an approximate soluble/insoluble compound ratio of 1:1 were observed in non-pigmented rice. Pigmented rice displayed a greater inhibitory effect on ACE than non-pigmented rice. In fact, a significant correlation between the content of soluble phenolics and ACE inhibition was observed (r = 0.8985, p < 0.05). In addition to significantly reducing the levels of total phenolics and ACE inhibition, cooking altered the soluble/insoluble compound ratio, especially among red rice genotypes. (C) 2011 Elsevier Ltd. All rights reserved.

EFFECT OF THERMAL TREATMENT ON PHENOLIC COMPOUNDS AND FUNCTIONALITY LINKED TO TYPE 2 DIABETES AND HYPERTENSION MANAGEMENT OF PERUVIAN AND BRAZILIAN BEAN CULTIVARS (PHASEOLUS VULGARIS L.) USING IN VITRO METHODS

The effect of thermal treatment on phenolic compounds and type 2 diabetes functionality linked to alpha-glucosidase and alpha-amylase inhibition and hypertension relevant angiotensin I-converting enzyme (ACE) inhibition were investigated in selected bean (Phaseolus vulgaris L,) cultivars from Peru and Brazil using in vitro models. Thermal processing by autoclaving decreased the total phenolic content in all cultivars, whereas the 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity-linked antioxidant activity increased among Peruvian cultivars, alpha-Amylase and alpha-glucosidase inhibitory activities were reduced significantly after heat treatment (73-94% and 8-52%, respectively), whereas ACE inhibitory activity was enhanced (9-15%). Specific phenolic acids such as chlorogenic and caffeic acid increased moderately following thermal treatment (2-16% and 5-35%, respectively). No correlation was found between phenolic contents and functionality associated to antidiabetes and antihypertension potential, indicating that non phenolic compounds may be involved. Thermally processed bean cultivars are interesting sources of phenolic acids linked to high antioxidant activity and show potential for hypertension prevention.

Comparative study of phenolic compounds in different Brazilian rice (Oryza sativa L.) genotypes

This study was conducted to evaluate the natural variability of total, extractable and non-extractable phenolics in pigmented and non-pigmented rice genotypes (Oryza sativa L.) and to estimate whether the contents and distribution of these compounds are typical for genotypes from indica and japonica subspecies. Twenty-one samples of commercial as well as new genotypes of brown rice, including seven pigmented genotypes were obtained from two Agronomic Institutes in South Brazil. Free and conjugated phenolics were extracted with ethanol, while bound phenolics were released by alkaline hydrolysis. Total phenolics were estimated in both fractions by the Folin-Ciocalteau method. Genotypes from Japonica and indica non-pigmented subspecies were not statistically distinguishable from each other, but differences in phenolic contents were associated with pericarp color. Despite individual differences, total phenolics were four times higher in pigmented than in non-pigmented genotypes (4246 and 1073 mg ferulic acid equiv. kg(-1), respectively). These high amounts were mostly due to the presence of extractable (free and conjugated) phenolics, which comprised up to 81% of total phenolics for pigmented genotypes. Non-extractable (bound) phenolics comprised 40% of total phenolics of non-pigmented rice genotypes while pigmented genotypes presented greater absolute amounts, but their contribution on total phenolics was small. (C) 2008 Elsevier Inc. All rights reserved.

Effect of Different Cooking Conditions on Phenolic Compounds and Antioxidant Capacity of Some Selected Brazilian Bean (Phaseolus vulgaris L.) Cultivars

The effects of different cooking conditions such as soaking, atmospheric (100 degrees C) or pressure boiling (121 degrees C), and draining of cooking water following thermal treatment on phenolic compounds and the DPPH radical scavenging capacity from two selected Brazilian bean cultivars (black and yellow-brown seed coat color) were investigated using a factorial design (2(3)). Factors that significantly reduced the total phenolic contents and antioxidant capacity in both cultivars were the soaking and draining stage. Independent of cooking temperature, total phenolics and antioxidant capacities were enhanced in treatments without soaking and where cooking water was not discarded, and this was likely linked to an increase of specific phenolic compounds detected by high performance liquid chromatography such as flavonols and free phenolic acids in both cultivars. Cooking of beans either at 100 or 121 degrees C, without a soaking stage and keeping the cooking water, would be recommendable for retaining antioxidant phenolic compounds.

Determination of volatiles produced during radiation processing in Laurus cinnamomum

In order to protect food from pathogenic microorganisms as well as increase its shelf-life, while keeping sensorial properties (e.g., odor and taste), which are important properties required by spice buyers, it is necessary to analyze volatile formation from irradiation of medicinal and food herbs. Possible changes in the odor of these herbs are evaluated by characterizing different radiation doses and effects on sensorial properties, in order to allow better application of the irradiation technology. The aim of the present study was to analyze volatile formation on cinnamon (Laurus cinnamomum) samples after gamma irradiation. These samples were irradiated into plastic packages using a (60)Co facility. Radiation doses applied were 0, 5, 10, 15, 20 and 25 kGy. For the analysis of the samples, solid-phase microextraction (SPME) was applied, while for the analysis of volatile compounds, CG/MS. Spice irradiation showed the highest decrease in volatile compounds. For L. cinnamomum, the irradiation decreased volatile compounds by nearly 56% and 89.5%, respectively, comparing to volatile from a sample which had not been previously irradiated. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.

Chemical characterization, bioactive compounds, and antioxidant capacity of jussara (Euterpe edulis) fruit from the Atlantic Forest in southern Brazil

Samples of fruit from the jussara palm plant (Euterpe edulis), collected in different regions of the state of Santa Catarina. Brazil, were analyzed for chemical composition. phenolic acids. anthocyanins, flavonoids and fatty acids profile. Results indicated that the jussara fruit has a high lipid content (18.45-44.08%), oleic acid (44.17-55.61%) and linoleic acid (18.19-25.36%) are the fatty acids found in the highest proportion, and other components were proteins (5.13-8.21%). ash (1.55-3.32%) and moisture (34.95-42.47%). Significant differences were found in the total phenolic, total monomeric anthocyanins and other flavonoids for the samples from the five cultivation regions. The fruit from region E harvested in summer, with high temperatures and medium altitudes, had the highest contents of total phenolics (2610.86 +/- 3.89 mg 100 g(-1) GAE) and monomeric anthocyanins (1080.54 +/- 2.33 mg 100g(-1) cy-3-glu). The phenolic compound included ferulic, gallic, hydroxybenzoic and p-coumaric acids, as well as catechin, epicatechin and quercetin. The results show promising perspectives for the exploitation of this tropical fruit with a chemical composition comprising considerable phenolic acids and flavonoids compounds and showing activity antioxidant. (C) 2010 Published by Elsevier Ltd.

Functionality of bioactive compounds in Brazilian strawberry (Fragaria x ananassa Duch.) cultivars: Evaluation of hyperglycemia and hypertension potential using in vitro models

Fruits of seven fully ripened strawberry cultivars grown in Brazil (Dover, Camp Dover, Camarosa, Sweet Charlie, Toyonoka, Oso Grande, and Piedade) were evaluated for total phenolics, antioxidant activity based on DPPH radical scavenging assay, and functionality such as inhibition of alpha-amylase, alpha-glucosidase, and angiotensin I-converting enzyme (ACE) relevant for potentially managing hyperglycemia and hypertension. The total phenolics content ranged from 966 to 1571 mu g of gallic acid/g of fruit fresh weight for Toyonoka and Dover, respectively. No correlation was found between total phenolics and antioxidant activity. The major phenolic compounds in aqueous extracts of strawberries were ellagic acid, quercetin, and chlorogenic acid. Strawberries had high alpha-glucosidase inhibitory activity. However, alpha-amylase inhibitory activity was very low in all cultivars. This suggested that strawberries could be considered as a potential dietary source with anti-hyperglycemic potential. The evaluated cultivars had no significant ACE inhibitory activity, reflecting low anti-hypertensive potential.