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Fungal species in the Nectriaceae, such as Fusarium spp. (Hypocreales: Nectriaceae), are etiologic agents of hyalohyphomycosis capable of producing violaceous or yellowish pigments under certain conditions, while Curvularia spp. (Pleosporales: Pleosporaceae) are agents of phaeohyphomycosis and typically produce melanin in their cell walls. In nectriaceous and pleosporaceous fungi, these pigments are mainly constituted by polyketides (e.g., azaphilones, naphthoquinones, and hydroxyanthraquinones). Considering the importance of pigments synthesized by these genera, this work focused on the selective extraction of pigments produced by eight Fusarium solani species complex and one Curvularia verruculosa isolate recovered from dermatomycosis specimens, their separation, purification, and posterior chemical analysis. The pigments were characterized through spectral and acid-base analysis, and their maximum production time was determined. Moreover, spectral identification of isolates was carried out to approach the taxonomic specificity of pigment production. Herein we describe the isolation and characterization of three acidic pigments, yellowish and pinkish azaphilones (i.e., coaherin A and sclerotiorin), and a purplish xanthone, reported for the first time in the Nectriaceae and Pleosporaceae, which appear to be synthesized in a species-independent manner, in the case of fusaria.

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The variations of the elemental concentrations in sparkling white wine and respective cork stoppers throughout 18 months of storage time were determined with the PIXE (Particle-Induced X-ray Emission) technique. Three portions of the cork stoppers were analyzed: the top part (external layer), the inner part (bulk layer) and the bottom layer (which was in contact with the sparkling wine). Elements such as Na, Mg, Si, P, S, Cl, K, Ca, Mn, Fe, Zn and Rb were determined for both cork stoppers and sparkling wine samples. Similar concentrations of Si, P, S, Cl and Ca were found in the external and bottom layers of the corks. Distinct behaviors of the changes in the elemental concentrations as a function of the time were observed for cork stoppers and sparkling wines. The concentrations of Mg, S, K, Ca, Cu, Sr and Ba increased in the bottom layer of the cork as a function of storage time. On the other hand, concentrations of Al, Si, Cl, Ti, Zn and Br proved to be invariant, while the concentrations of P and Fe showed a slight decrease. Concerning the sparkling wine, an increasing trend of elemental concentrations was observed for most elements throughout the storage time. A diffusion mechanism of elements in the cork and the role of the secondary fermentation in the bottle are discussed.

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Resumen En la presente investigación se prepararon sólidos porosos tipo carbón activado (CA) a partir de la activación química del cuesco de palma africana procedente de los cultivos de la región de la Guajira, Colombia, con soluciones de Fe(NO3)3 y Cu(NO3)2 con cambio en la concentración a dos diferentes temperaturas: 973 y 1073 K. Los sólidos adsorbentes preparados se caracterizaron para determinar sus propiedades fisicoquímicas y capacidades de adsorción de CO2. Los CA obtenidos presentan micro mesoporosidad con áreas superficiales entre 5 y 1300 m2g-1. Los valores con respecto al contenido de carbono fijo se encuentran entre 47,1 y 78,4%; los resultados evidencian que el proceso de activación tiene efectos sobre los parámetros texturales, composición elemental y proximal de los sólidos obtenidos. También se realizó la caracterización morfológica de la superficie de los materiales con SEM evidenciando la formación de mayor rugosidad en las muestras activadas a 1073 K, específicamente, los carbones activados con el nitrato cúprico; además, mediante EDX se cuantificó la presencia de algunos elementos. Los valores obtenidos de la adsorción de CO2 a bajas presiones se encuentran entre 80 y 250 mg•g-1, evidenciándose una mayor afinidad hacia los sólidos adsorbentes (MCu3 y MFe5).

Abstract In the present investigation, porous solids type activated carbon (CA) were prepared from the chemical activation of the African palm shells from the crops of the Guajira region, Colombia, with solutions of Fe(NO3)3 and Cu(NO3)2 with change in concentration at two different temperatures: 973 and 1073 K. The prepared adsorbent solids were characterized to determine their physicochemical properties and CO2 adsorption capacities. The CAs obtained present micro-mesoporosity with surface areas between 5 and 1300 m2g-1. The values with respect to the fixed carbon content are between 47.1% and 78.4%; the results show that the activation process has effects on the textural parameters, elemental and proximal composition of the solids obtained. The morphological characterization of the surface of the materials was also carried out with SEM, evidencing the formation of greater roughness in the samples activated at 1073 K, specifically, the activated carbons with cupric nitrate; furthermore, the presence of some elements was quantified by EDX. The values obtained from the adsorption of CO2 at low pressures are between 80 and 250 mg•g-1, showing a greater affinity towards adsorbent solids (MCu3 and MFe5).

Resumo Na presente investigação, sólidos porosos do tipo carvão ativado (CA) foram preparados a partir da ativação química do Cuesco de Palma Africana de lavouras da região de Guajira-Colômbia com soluções de Fe(NO3)3 e Cu(NO3)2 com alteração em concentração em duas temperaturas diferentes 973 e 1073 K. Os materiais preparados foram caracterizados para avaliar suas propriedades físico-químicas e capacidades de adsorção de CO2. Os (CAs) obtidos apresentam micro-mesoporosidade com áreas superficiais entre 5 e 1300 m g-1. Os valores com relação ao teor de carbono fixo estão entre 47,1 - 78,4%, os resultados mostram que o processo de ativação tem efeitos nos parâmetros texturais, composição elementar e proximal dos sólidos obtidos. A caracterização morfológica da superfície dos materiais também foi realizada com MEV, evidenciando a formação de maior rugosidade nas amostras ativadas a 1073 K, especificamente os carbonos ativados com nitrato cúprico, e a presença de alguns elementos foi quantificada por EDX. Os valores obtidos na adsorção de CO2 em baixas pressões estão entre 80-250 mg•g-1, mostrando uma maior afinidade para sólidos adsorventes (MCu3 e MFe5).

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Herbal infusions are amongst the world's most popular and widely enjoyed beverages, due to both large variety and convenience. However, natural contaminants, such as mycotoxins and trace elements can accumulate in aromatic herbs, which may have serious food safety and public health implications. In this study, the presence of mycotoxins, as well as the content of trace elements was evaluated in herbs and herbal infusions commercialized in Brazil. For the determination of fourteen mycotoxins, including the emerging mycotoxins enniatins (EN), beauvericin (BEA), and sterigmatocystin (STE), a liquid-chromatography tandem mass spectrometry (LC-MS/MS) method was validated. Overall, 42 out of 58 herb samples (72%) were contaminated, being BEA the most usual mycotoxin, present in 43% of the samples, followed by STE and HT-2 toxin, present in 37% and 24% of the samples, respectively. In herbal infusions, the occurrence of mycotoxins was 88% lesser than those verified in raw products. Despite these low levels, the hazard quotient (HQ) calculated revealed a potential health concern for HT-2 in infusions. The margin of exposure values for aflatoxins (AF), and ochratoxin A (OTA) from six herbal infusions were below 10,000, indicating also potential health risks. The twenty-one trace elements comprising toxic elements such as arsenic (As), cadmium (Cd), and lead (Pb) were determined in herb raw materials by inductively coupled plasma-mass spectrometry (ICP-MS). The levels of trace elements in herbs were very varied, with aluminum (Al) presenting the highest amount. The levels of legislated elements (As, Cd, Pb) analyzed in herbs were lower than 3.03 µg g-1 (Pb), thus not exceeding the legal limits defined for herbal medicinal by both European and Brazilian pharmacopeia.

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Abstract It was evaluated the effect of operational conditions in the production of Chlorella sp. after its selection from genus Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. and Dunaliella salina. Microalgae were inoculated in drinking water with addition of NPK fertilizer (N 24%, P 24%, K 18%), at a concentration of 0.5 g/L, agitation of 150 rpm, temperature 25 °C, light intensity of 1680 lumens at a color temperature of 6400K, without pH control for 8 days. The cellular concentrations obtained were 3.72x107 (Chlorella sp.), 1.36x107 (Scenedesmus sp.), 3.55x107 (Tetraselmis sp.), 5.74x107 (Nannochloris sp.) and 3.45x106 (Dunaliella salina), where the microalgae Chlorella sp., shows invasive capacity in drinking water cultivations. Applying the 2n-p fractional factorial design concept for the elemental composition of the microalgae and the cellular morphology, it was obtained 44.33% of C, 7.09% of H, 8.53% of N and 0.84% ​​of S for the Chlorella sp.

Resumo Foi avaliado o efeito das condições operacionais na produção de Chlorella sp. após a seleção do gênero Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. e Dunaliella salina. Microalgas foram inoculadas em água potável com adição de fertilizante NPK (N 24%, P 24% e K 18%), na concentração de 0,5 g/L, agitação de 150 rpm, temperatura de 25 °C, intensidade luminosa de 1.680 lúmens para uma temperatura de cor de 6.400 K, sem controle de pH por 8 dias. As concentrações celulares obtidas foram de 3,72 x 107 (Chlorella sp.), 1,36 x 107 (Scenedesmus sp.), 3,55 x 107 (Tetraselmis sp.), 5,74 x 107 (Nannochloris sp.) e 3,45 x 106 (Dunaliella salina), em que a microalga Chlorella sp. mostrou capacidade invasiva em cultivos de água potável. Aplicando o conceito de projeto fatorial fracionado 2n-p para a composição elementar da microalga e a morfologia celular, foram obtidos 44,33% de C, 7,09% de H, 8,53% de N e 0,84% de S para a Chlorella sp.

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It was evaluated the effect of operational conditions in the production of Chlorella sp. after its selection from genus Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. and Dunaliella salina. Microalgae were inoculated in drinking water with addition of NPK fertilizer (N 24%, P 24%, K 18%), at a concentration of 0.5 g/L, agitation of 150 rpm, temperature 25 °C, light intensity of 1680 lumens at a color temperature of 6400K, without pH control for 8 days. The cellular concentrations obtained were 3.72x107 (Chlorella sp.), 1.36x107 (Scenedesmus sp.), 3.55x107 (Tetraselmis sp.), 5.74x107 (Nannochloris sp.) and 3.45x106 (Dunaliella salina), where the microalgae Chlorella sp., shows invasive capacity in drinking water cultivations. Applying the 2n-p fractional factorial design concept for the elemental composition of the microalgae and the cellular morphology, it was obtained 44.33% of C, 7.09% of H, 8.53% of N and 0.84% of S for the Chlorella sp.(AU)

Foi avaliado o efeito das condições operacionais na produção de Chlorella sp. após a seleção do gênero Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. e Dunaliella salina. Microalgas foram inoculadas em água potável com adição de fertilizante NPK (N 24%, P 24% e K 18%), na concentração de 0,5 g/L, agitação de 150 rpm, temperatura de 25 °C, intensidade luminosa de 1.680 lúmens para uma temperatura de cor de 6.400 K, sem controle de pH por 8 dias. As concentrações celulares obtidas foram de 3,72 x 107 (Chlorella sp.), 1,36 x 107 (Scenedesmus sp.), 3,55 x 107 (Tetraselmis sp.), 5,74 x 107 (Nannochloris sp.) e 3,45 x 106 (Dunaliella salina), em que a microalga Chlorella sp. mostrou capacidade invasiva em cultivos de água potável. Aplicando o conceito de projeto fatorial fracionado 2n-p para a composição elementar da microalga e a morfologia celular, foram obtidos 44,33% de C, 7,09% de H, 8,53% de N e 0,84% de S para a Chlorella sp.(AU)

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Jaboticaba, Plinia cauliflora (Mart.) Kausel, is a Brazilian berry traditionally used in folk medicine as treatment for some health conditions. Phenolic compounds such as flavonoids and anthocyanins have previously been detected in the fruit. This current study aimed to evaluate the toxicological effects of jaboticaba peel extract (JPE) on Artemia salina, L929, and MDA-MB-231 cell lines. Besides, JPE antioxidant, acetylcholinesterase, and antifungal activities, and elemental analysis CHNS were also tested. JPE had moderate toxicity (LD50 = 360.92 µg mL-1) on A. salina, non-toxic effect on L929 cell line, and decreased the viability of cancer cell line MDA at 1,000 µg mL-1 and 500 µg mL-1 concentrations. The antioxidant activity toward 2,2-diphenyl-1-picrylhydrazyl (DPPH) performed IC50 = 37.45 ± 0.17 µg mL-1, whereas 45.7% of acetylcholinesterase activity was inhibited. By its elemental composition, JPE is an alternative food supplement and dermocosmetic component. Antifungal potential toward Candida strains was not observed.

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We report a complete set of strategies for characterization and an accurate determination of gold in metallic nanoparticles. For this, gold nanorods (AuNR) were synthesized by using the surfactant hexadecyltrimethylammonium bromide (CTAB) as the stabilizer and shape-directing agent. The surfactant CTAB forms a bilayer structure around the nanoparticles and became a challenge for the development of the microwave-assisted decomposition of the AuNR colloid. The bilayer structure of CTAB prevents the Au3+ release for the acidic media during the decomposition procedure. To overcome this limitation, a combination of low sample volume consumption (only 200 µL), an acidic mixture of reverse aqua regia (1:3 v/v, HCl:HNO3), and sulfuric acid, and a microwave program was used. The gold quantification by ICP-MS and checked through the ICP OES, demonstrated that the seed-mediated growth method used for the AuNR synthesis has a high yield, presenting ca. 100% of gold content (ca. 100 mg L-1 of gold concentration) in the post-synthesis colloid (AuNR-total) as well as in the colloid after a washing step (AuNR-res). The microwave-assisted decomposition procedure also demonstrated to be efficient in the acidic decomposition of the gold-silver core-shell nanoparticle (Au@AgNR), which presents a high content of polyvinylpyrrolidone (PVP) (Mw ~55000 g mol-1) acting as a stabilizer, in addition to the matrix with CTAB. The results demonstrated an accurate recovery of ca. 100% of gold content for the Au@AgNR regarding the gold nanorod before the growth of the silver shell (AuNR_Core). The proposed microwave-assisted decomposition platform demonstrated to be an efficient, reliable, and robust characterization tool for the gold quantification in metallic nanoparticles, presenting no interference of the complex matrix with high organic content.

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Insect epidermal cells secrete a cuticle that serves as an exoskeleton providing mechanical rigidity to each individual, but also insulation, camouflage or communication within their environment. Cuticle deposition and hardening (sclerotization) and pigment synthesis are parallel processes requiring tyrosinase activity, which depends on an unidentified copper-dependent enzyme component in Drosophila melanogaster. We determined the metallomes of fly strains selected for lighter or darker cuticles in a laboratory evolution experiment, asking whether any specific element changed in abundance in concert with pigment deposition. The results showed a correlation between total iron content and strength of pigmentation, which was further corroborated by ferritin iron quantification. To ask if the observed increase in iron body content along with increased pigment deposition could be generalizable, we crossed yellow and ebony alleles causing light and dark pigmentation, respectively, into similar genetic backgrounds and measured their metallomes. Iron remained unaffected in the various mutants providing no support for a causative link between pigmentation and iron content. In contrast, the combined analysis of both experiments suggested instead a correlation between pigment deposition and total copper body content, possibly due to increased demand for epidermal tyrosinase activity.

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Brazil stands out as one of the largest world powers in the agribusiness sector, and with the increase of production capacity, an enormous amount of waste is generated that cause serious environmental problems. Acerola is evidenced as one of the fruits of growing and important commercialization, contributing significantly to regional development through the export of concentrated powder product. Thus, in order to minimize the environmental impacts generated by the local fruit processing industry, the proximate analysis of its residue after drying in a convective oven at temperatures of 50, 75 and 100 °C was carried out in this work, aiming at the reuse of this residue for thermochemical processes. Moisture, ash, volatile matter (VM), and fixed carbon (FC) content were analyzed, as well as characterizations, such as infrared spectroscopy (FTIR), elemental analysis (CHNO), calorific value (HHV) and thermogravimetry (TG/DTG). The results showed a significant difference in the moisture contents, VM, FC and elemental carbon for the dry residue at 50 °C compared to the temperatures of 75 and 100 °C, while for the ash content there was no significant difference between the temperatures. The dry acerola residue at the three temperatures studied presented adequate properties for thermochemical application, with lignocellulosic compounds that can be converted by thermochemical route, good levels of calorific power, low moisture and ash content, associated with high amount of volatile matter.

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The multi-isotope calibration (MICal) is a fast and accurate calibration strategy for multi-elemental determination that uses only two solutions, (1) 50% (v v-1) sample plus 50% (v v-1) analytical blank solution, and (2) 50% (v v-1) sample plus 50% (v v-1) standard solution (containing the analytes). The calibration curves were built as a function of the intensity signals of solution 1 (y-axis) versus solution 2 (x-axis), employing the various isotopes of each monitored mass/charge. The concentration of the analytes was calculated from the slope and the concentrations of the standards added to solution 2. The validation of the method was evaluated using standard reference materials of bovine liver and bovine muscle. The recoveries varied from 87 to 113% for MICal, which were similar to the conventional standard additions calibration procedure (83 to 120%).

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Abstract It was evaluated the effect of operational conditions in the production of Chlorella sp. after its selection from genus Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. and Dunaliella salina. Microalgae were inoculated in drinking water with addition of NPK fertilizer (N 24%, P 24%, K 18%), at a concentration of 0.5 g/L, agitation of 150 rpm, temperature 25 °C, light intensity of 1680 lumens at a color temperature of 6400K, without pH control for 8 days. The cellular concentrations obtained were 3.72x107 (Chlorella sp.), 1.36x107 (Scenedesmus sp.), 3.55x107 (Tetraselmis sp.), 5.74x107 (Nannochloris sp.) and 3.45x106 (Dunaliella salina), where the microalgae Chlorella sp., shows invasive capacity in drinking water cultivations. Applying the 2n-p fractional factorial design concept for the elemental composition of the microalgae and the cellular morphology, it was obtained 44.33% of C, 7.09% of H, 8.53% of N and 0.84% of S for the Chlorella sp.

Resumo Foi avaliado o efeito das condições operacionais na produção de Chlorella sp. após a seleção do gênero Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. e Dunaliella salina. Microalgas foram inoculadas em água potável com adição de fertilizante NPK (N 24%, P 24% e K 18%), na concentração de 0,5 g/L, agitação de 150 rpm, temperatura de 25 °C, intensidade luminosa de 1.680 lúmens para uma temperatura de cor de 6.400 K, sem controle de pH por 8 dias. As concentrações celulares obtidas foram de 3,72 x 107 (Chlorella sp.), 1,36 x 107 (Scenedesmus sp.), 3,55 x 107 (Tetraselmis sp.), 5,74 x 107 (Nannochloris sp.) e 3,45 x 106 (Dunaliella salina), em que a microalga Chlorella sp. mostrou capacidade invasiva em cultivos de água potável. Aplicando o conceito de projeto fatorial fracionado 2n-p para a composição elementar da microalga e a morfologia celular, foram obtidos 44,33% de C, 7,09% de H, 8,53% de N e 0,84% de S para a Chlorella sp.

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The water-soluble melanins (SM) of Randia echinocarpa fruit possess interesting biological activities and have been scarcely characterized. In this study, SM were obtained at boiling (SMBT) and room (SMRT) temperatures and characterized by UV-Vis, IR, thermogravimetric analysis, and GC-MS of the hydrolysis products of the SM; besides, the solid-state 13 C NMR, elemental analysis, and acute and sub-acute toxicity of the SMBT were determined. SMBT and SMRT contain organic acids and carbohydrates and their spectroscopic signals and thermograms were similar, but the SMBT yield was higher. The SMBT were characterized by their elemental composition (C 48.260 ± 0.011%, N 3.693 ± 0.009% and H 6.093 ± 0.076%) consistent with the presence of aromatic rings and eumelanins, degradation temperature at 300°C, 13 C NMR signals supporting melanin-bonding with carbohydrates and organic acids, and innocuity in Balb/C mice (acute assay, LD50  > 5 g/kg b.w.; sub-acute assay, no lethality at 500 mg/kg b.w. for 30 days). PRACTICAL APPLICATIONS: The consumption of melanins has been associated with health benefits because of their biological activities (e.g., antioxidant, immunostimulatory, UV- and radiation-protective). Randia echinocarpa is employed in Mexican traditional medicine against chronic degenerative diseases (e.g., cancer and diabetes) and ailments of organs (e.g., kidney and lung) and systems (e.g., circulatory and gastrointestinal). The R. echinocarpa fruit contains water-soluble melanins (SM) that inhibit carbohydrate-digestive enzymes and show high antioxidant activity; thus, SM could be useful for the prevention and treatment of diabetes. This study showed that the SM structure contains melanin-bonding organic acids and carbohydrates, which could be associated with the SM solubility and higher yield, and that SMBT were innocuous in the acute and sub-acute assays in mice. Thus, the R. echinocarpa SMBT could be used as safe potential ingredients to develop functional products.

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Sangiovese is the most widespread Italian red cultivar and constitutes the basis of internationally known wines such as Chianti and Brunello di Montalcino. Outside of Europe, Argentina is the largest producer, followed by the United States. This study sought to define and compare 2016 vintage Sangiovese wine composition from various production regions in California and Italy. Forty-six commercial Sangiovese wines from California and Italy were analyzed for volatile profile, color, phenolic, and elemental content. This study demonstrates that it is possible to determine regional differences among wines based on these chemical profiles. However, some Californian and Italian wine had similar chemical compositions. In order to compare Californian and Italian wines, Californian wine reference models were developed using the chemical parameters from Sangiovese wines, performing a Soft Independent Modeling of Class Analogy (SIMCA). To our knowledge, this is the first time that an extensive regionality study has been attempted for Sangiovese wines.

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This study approaches the determination of nine elements from Brazilian carbonated soft drinks of several flavors and manufactures using inductively coupled plasma optical emission spectrometry (ICP OES). The concentrations of the elements varied as follows: (in µg L-1: Cu: 4.00-78.0; Fe: 74.0-506; Mn: 20.0-66.0; Zn: 104-584) and (in mg L-1: Ca: 4.81-16.2; K: 6.73-260; Na: 26.0-175; S: 1.43-5.41; P: 0.186-219). Principal component analysis has shown some tendencies to form two groups according to the drink flavor (orange and cola), but only cola presented a clear and complete separation. Using Kohonen maps, it was observed a tendency to form three flavor groups: (i) cola, (ii) orange and lemon, and (iii) guarana. However, this last tool proved to be more accurate in the groups' formation.

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Plants allocate nutrients to specific leaf cell types, with commelinoid monocots preferentially allocating phosphorus (P) to the mesophyll and calcium (Ca) to the epidermis, whereas the opposite is thought to occur in eudicots. However, Proteaceae from severely P-impoverished habitats present the same P-allocation pattern as monocots. This raises the question of whether preferential P allocation to mesophyll cells is a phylogenetically conserved trait, exclusive to commelinoid monocots and a few Proteaceae, or a trait that has evolved multiple times to allow plants to cope with very low soil P availability. We analysed the P-allocation patterns of 16 species from 10 genera, eight families and six orders within three major clades of eudicots across different P-impoverished environments in Australia and Brazil, using elemental X-ray mapping to quantitatively determine leaf cell-specific nutrient concentrations. Many of the analysed species showed P-allocation patterns that differed substantially from that expected for eudicots. Instead, P-allocation patterns were strongly associated with the P availability in the natural habitat of the species, suggesting a convergent evolution of P-allocation patterns at the cellular level, with P limitation as selective pressure and without a consistent P-allocation pattern within eudicots. Here, we show that most eudicots from severely P-impoverished environments preferentially allocated P to their mesophyll. We surmise that this preferential P allocation to photosynthetically active cells might contribute to the very high photosynthetic P-use efficiency of species adapted to P-impoverished habitats.

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Plants allocate nutrients to specific leaf cell types; eudicots are thought to predominantly allocate phosphorus (P) to epidermal/bundle sheath cells. However, three Proteaceae species have been shown to preferentially allocate P to mesophyll cells instead. These Proteaceae species are highly adapted to P-impoverished habitats, with exceptionally high photosynthetic P-use efficiencies (PPUE). We hypothesized that preferential allocation of P to photosynthetic mesophyll cells is an important trait in species adapted to extremely P-impoverished habitats, contributing to their high PPUE. We used elemental X-ray mapping to determine leaf cell-specific nutrient concentrations for 12 Proteaceae species, from habitats of strongly contrasting soil P concentrations, in Australia, Brazil, and Chile. We found that only species from extremely P-impoverished habitats preferentially allocated P to photosynthetic mesophyll cells, suggesting it has evolved as an adaptation to their extremely P-impoverished habitat and that it is not a family-wide trait. Our results highlight the possible role of soil P in driving the evolution of ecologically relevant nutrient allocation patterns and that these patterns cannot be generalized across families. Furthermore, preferential allocation of P to photosynthetic cells may provide new and exciting strategies to improve PPUE in crop species.

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The feasibility of the application of chemometric techniques associated with multi-element analysis for the classification of grape seeds according to their provenance vineyard soil was investigated. Grape seed samples from different localities of Mendoza province (Argentina) were evaluated. Inductively coupled plasma mass spectrometry (ICP-MS) was used for the determination of twenty-nine elements (Ag, As, Ce, Co, Cs, Cu, Eu, Fe, Ga, Gd, La, Lu, Mn, Mo, Nb, Nd, Ni, Pr, Rb, Sm, Te, Ti, Tl, Tm, U, V, Y, Zn and Zr). Once the analytical data were collected, supervised pattern recognition techniques such as linear discriminant analysis (LDA), partial least square discriminant analysis (PLS-DA), k-nearest neighbors (k-NN), support vector machine (SVM) and Random Forest (RF) were applied to construct classification/discrimination rules. The results indicated that nonlinear methods, RF and SVM, perform best with up to 98% and 93% accuracy rate, respectively, and therefore are excellent tools for classification of grapes.

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The optimization of bilayer coverage on particles is important for a variety of biomedical applications, such as drug, vaccine, and genetic material delivery. This work aims at optimizing the deposition of cationic bilayers on silica over a range of experimental conditions for the intervening medium and two different assemblies for the cationic lipid, namely, lipid films or pre-formed lipid bilayer fragments. The lipid adsorption on silica in situ over a range of added lipid concentrations was determined from elemental analysis of carbon, hydrogen, and nitrogen and related to the colloidal stability, sizing, zeta potential, and polydispersity of the silica/lipid nanoparticles. Superior bilayer deposition took place from lipid films, whereas adsorption from pre-formed bilayer fragments yielded limiting adsorption below the levels expected for bilayer adsorption.

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Abstract It was evaluated the effect of operational conditions in the production of Chlorella sp. after its selection from genus Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. and Dunaliella salina. Microalgae were inoculated in drinking water with addition of NPK fertilizer (N 24%, P 24%, K 18%), at a concentration of 0.5 g/L, agitation of 150 rpm, temperature 25 °C, light intensity of 1680 lumens at a color temperature of 6400K, without pH control for 8 days. The cellular concentrations obtained were 3.72x107 (Chlorella sp.), 1.36x107 (Scenedesmus sp.), 3.55x107 (Tetraselmis sp.), 5.74x107 (Nannochloris sp.) and 3.45x106 (Dunaliella salina), where the microalgae Chlorella sp., shows invasive capacity in drinking water cultivations. Applying the 2n-p fractional factorial design concept for the elemental composition of the microalgae and the cellular morphology, it was obtained 44.33% of C, 7.09% of H, 8.53% of N and 0.84% of S for the Chlorella sp.

Resumo Foi avaliado o efeito das condições operacionais na produção de Chlorella sp. após a seleção do gênero Chlorella sp., Scenedesmus sp., Nannochloris sp., Tetraselmis sp. e Dunaliella salina. Microalgas foram inoculadas em água potável com adição de fertilizante NPK (N 24%, P 24% e K 18%), na concentração de 0,5 g/L, agitação de 150 rpm, temperatura de 25 °C, intensidade luminosa de 1.680 lúmens para uma temperatura de cor de 6.400 K, sem controle de pH por 8 dias. As concentrações celulares obtidas foram de 3,72 x 107 (Chlorella sp.), 1,36 x 107 (Scenedesmus sp.), 3,55 x 107 (Tetraselmis sp.), 5,74 x 107 (Nannochloris sp.) e 3,45 x 106 (Dunaliella salina), em que a microalga Chlorella sp. mostrou capacidade invasiva em cultivos de água potável. Aplicando o conceito de projeto fatorial fracionado 2n-p para a composição elementar da microalga e a morfologia celular, foram obtidos 44,33% de C, 7,09% de H, 8,53% de N e 0,84% de S para a Chlorella sp.