Caracterização química da amêndoa de coquinho-azedo (Butia capitata var capitata)

A palmeira Butia capitata var capitata produz o coquinho-azedo, fruto de odor agradável e penetrante, cuja polpa é aproveitada para a produção de um suco saboroso na região norte de Minas Gerais. As sementes apresentam uma amêndoa cuja exploração ainda é bastante limitada. O objetivo deste trabalho foi determinar a composição da amêndoa do coquinho-azedo, visando a avaliar suas possibilidades de uso. Na amêndoa, a composição química (umidade, proteínas, lipídios, cinzas e fibras) foi determinada por métodos gravimétricos. Os teores dos principais minerais foram avaliados por espectrofotometria de emissão atômica com fonte de plasma indutivo, e a composição dos ácidos graxos presentes na gordura da semente foi determinada por cromatografia a gás. A amêndoa do coquinho-azedo apresentou 9,9 % de umidade e 57,8 % de lipídios totais, 25,8 % de fibra detergente neutro, 17,6 % de fibra detergente ácido e 1,6 % de cinzas em base seca. A gordura extraída da amêndoa de coquinho-azedo apresentou elevados teores de ácido láurico (42,1 %), que foi seguido pelo ácido oléico (16,9 %). Predominaram os ácidos graxos saturados (78,9 %), principalmente os de cadeia média (C6-C12).

Caracterização da polpa do coquinho-azedo (Butia capitata var capitata)

O objetivo deste trabalho foi determinar a composição química, o teor de vitamina C, o valor pró-vitamina A e o teor de compostos fenólicos totais na polpa do coquinho-azedo (Butia capitata var capitata). Umidade, lipídeos, cinzas e fibras foram determinados por métodos gravimétricos; os minerais foram determinados por espectrometria de emissão atômica com fonte de plasma indutivo; o valor pró-vitamina A foi calculado através do teor de carotenóides; a vitamina C foi determinada por titulação com diclorofenolindofenol; os compostos fenólicos foram determinados pelo método de Folin-Ciocalteou, empregando ácido gálico e ácido tânico como padrões, e pelo método da vanilina, empregando catequina como padrão. A polpa, se comparada com outras frutas normalmente consumidas, apresentou elevado teor de óleo (2,5%), de fibra dietética (7,0%), de pró-vitamina A (146, 2RAE 100g-1), de vitamina C (53mg 100g-1), de compostos fenólicos (210mg de catequina, equivalente 100g-1; 116mg de ácido tânico, equivalente 100g-1) e de potássio (516mg 100g-1). O coquinho-azedo apresentou elevado potencial para enriquecer a alimentação da população local, especialmente como fonte de fibras, pró-vitamina A, vitamina C e potássio, a exemplo do que já vem sendo feito na merenda escolar no norte de Minas Gerais. Estes resultados demonstram o elevado valor de produtos oferecidos pelos pequenos agricultores, respaldando a importância cultural da espécie e valorizando a manutenção da variabilidade no cerrado.

Sour orange bud regeneration and in vitro plant development related to culture medium composition and explant type

In order to evaluate the formation of adventitious buds and in vitro regeneration of sour orange plants (Citrus aurantium L.) two organogenesis-inducing experiments were conducted. In the first experiment, the induction and in vitro regeneration of adventitious buds were tested on epicotyl and internodal segments under the influence of BAP or KIN associated with NAA. The second experiment evaluated the in vitro regeneration of sour orange plants related to different explant types (epicotyls segments, internodal segments of in vitro germinated plantlets and internodal segments of greenhouse cultivated plants). Data collected on both experiments included the percentage of responsive explants (explants that formed buds), and the number of buds per explant. The addition of BAP showed the best organogenic response. In vitro germinated epicotyl segments and internodal segments are recommended as explants for sour orange in vitro organogenesis. Rooting of regenerated shoots was achieved without the need of auxin in the medium.

Controle de tortricídeos em macieira com duas formulações de Bacillus thuringiensis var. Kustaki em Fraiburgo-SC

Grapholita molesta e Bonagota cranaodes são duas importantes pragas de pomares de macieira controlada por inseticidas. O objetivo deste estudo foi testar duas formulações de Bacillus thuringiensis var. kurstaki (Btk) para o controle desses tortricídeos. Parcelas de macieira 'Fuji' foram pulverizadas com Dipel PM e Dipel SC, nas concentrações de 100 ml por100 L de calda. A eficiência do Btk foi comparada com os inseticidas tebufenozide (Mimic 240 SC - 90 ml por 100 L) e clorpyrifos (Lorsban 480 BR - 150 ml por 100 L). Duas vezes por semana, eram avaliadas as capturas de pragas em armadilha do tipo Delta. As avaliações de danos nos frutos foram realizadas antes e na colheita, sendo classificados os frutos em função do agrupamento em cachopa e a sua localização na planta. Os tratamentos com Btk tiveram mais danos do que os químicos. Houve uma tendência de maiores danos na parte interna, próximo ao tronco das macieiras e o agrupamento dos frutos não influenciou na presença de danos. Ambas as formulações de Dipel foram eficientes quando comparados com Mimic e Lorsban.

Residual effect of growth regulators in etiolation and regeneration of in vitro pineapple plants

This work aimed to evaluate the influence of naphthaleneacetic acid (NAA) and gibberellic acid (GA3) plant regulators in in vitro etiolation and subsequent regeneration of the PE x SC-60 pineapple hybrid. Nodal segments of in vitro plants with approximately 5-7 cm height were incubated in basic MS culture medium supplemented with 0.0; 0.5 and 1.0 mg L-1 of naphthaleneacetic acid (NAA) in combination with gibberellic acid (GA3) in concentrations of 0.0; 0.5 and 1.0 mg L-1, and maintained at 27 ºC under dark condition. Evaluations were carried out at 90 and 180 days after incubation period. The best results for length of etiolated stems were obtained with 1.0 mg L-1 of NAA. In the experiment followed by the regeneration, stems with 3 cm from the etiolation treatment, were cultivated in proliferation medium and the number of regenerated plants per treatment was evaluated at 60 days of cultivation. The treatment that promoted the best etiolation of plants also promoted the worst regeneration rates, demonstrating the residual effect of the auxin used in the previous step in the regeneration of plants of the pineapple hybrid evaluated.

Diversity and genetic structure in natural populations of Hancornia speciosa var. speciosa Gomes in northeastern Brazil

Hancornia speciosa Gomes is a fruit tree native from Brazil that belongs to Apocinaceae family, and is popularly known as Mangabeira. Its fruits are widely consumed raw or processed as fruit jam, juices and ice creams, which have made it a target of intense exploitation. The extractive activities and intense human activity on the environment of natural occurrence of H. speciosa has caused genetic erosion in the species and little is known about the ecology or genetic structure of natural populations. The objective of this research was the evaluation of the genetic diversity and genetic structure of H. speciosa var. speciosa. The genetic variability was assessed using 11 allozyme loci with a sample of 164 individuals distributed in six natural populations located in the States of Pernambuco and Alagoas, Northeastern Brazil. The results showed a high level of genetic diversity within the species (e= 0.36) seeing that the most of the genetic variability of H. speciosa var. speciosa is within its natural populations with low difference among populations ( or = 0.081). The inbreeding values within ( = -0.555) and among populations ( =-0.428) were low showing lacking of endogamy and a surplus of heterozygotes. The estimated gene flow ( m ) was high, ranging from 2.20 to 13.18, indicating to be enough to prevent the effects of genetic drift and genetic differentiation among populations. The multivariate analyses indicated that there is a relationship between genetic and geographical distances, which was confirmed by a spatial pattern analysis using Mantel test (r = 0.3598; p = 0.0920) with 1000 random permutations. The high genetic diversity index in these populations indicates potential for in situ genetic conservation.

The role of gadoxetic acid as a paramagnetic contrast medium in the characterization and detection of focal liver lesions: a review

Recent studies have demonstrated that the use of paramagnetic hepatobiliary contrast agents in the acquisition of magnetic resonance images remarkably improves the detection and differentiation of focal liver lesions, as compared with extracellular contrast agents. Paramagnetic hepatobiliary contrast agents initially show the perfusion of the lesions, as do extracellular agents, but delayed contrast-enhanced images can demonstrate contrast uptake by functional hepatocytes, providing further information for a better characterization of the lesions. Additionally, this intrinsic characteristic increases the accuracy in the detection of hepatocellular carcinomas and metastases, particularly the small-sized ones. Recently, a hepatobiliary contrast agent called gadolinium ethoxybenzyl dimeglumine, that is simply known as gadoxetic acid, was approved by the National Health Surveillance Agency for use in humans. The authors present a literature review and a practical approach of magnetic resonance imaging utilizing gadoxetic acid as contrast agent, based on patients' images acquired during their initial experiment.

Composition and antifungal activity of essential oils from Piper aduncum, Piper arboreum and Piper tuberculatum

The composition of essential oils from leaves, stems and fruits of Piper aduncum, P. arboreum and P. tuberculatum was examined by means of GC-MS and antifungal assay. There was a predominance of monoterpenes in P. aduncum and P. tuberculatum and of sesquiterpenes in P. arboreum. P. aduncum showed the richest essential oil composition, including linalool. The essential oils from fruits of P. aduncum and P. tuberculatum showed the highest antifungal activity with the MIC of 10 µg as determined against Cladosporium cladosporioides and C. sphaerospermum, respectively. This is the first report of the composition of essential oils from P. tuberculatum.

Antifungal derivatives from Piper mollicomum and P. lhotzkyanum (Piperaceae)

Bioguided fractionation of the extracts from leaves of Piper mollicomum and Piper lhotzkyanum against the fungi Cladosporium cladosporioides and C. sphaerospermum afforded seven bioactive compounds, four being chromenes: methyl 2,2-dimethyl-2H-chromene-6-carboxylate, methyl 8-hydroxy-2,2-dimethyl-2H-chromene-6-carboxylate, 2-methyl-2-[4'-methyl-3'-pentenyl]-2H-1-benzopyran-6-carboxylic acid, 2,2-dimethyl-2H-chromene-6-carboxylic acid, one a dihydrochalcone: 2',6'-dihydroxy-4'-methoxydihydrochalcone, and two flavanones: 7-methoxy-5,4'-dihydroxy-flavanone and 7,4'-dimethoxy-5-hydroxy-flavanone. The structures of the bioactive isolated derivatives were elucidated by interpretation of their NMR data [¹H and 13C (BBD, DEPT 135º)], and mass spectral data as well as by comparison with data described in the literature.

Determinação de aflatoxina B1 em pimenta (Piper nigrum L.) e orégano (Origanum vulgare L.) por cromatografia em camada delgada e densitometria

An analytical study based on extraction with methanol-water, immunoaffinity cleanup and separation, identification and quantification of aflatoxin B1 by thin-layer chromatography,in ground black and white pepper and oregano was carried out. Validation of the applied methodology was done through accuracy and precision studies. Recoveries of aflatoxin B1 and relative standard deviations, from spice samples spiked at levels from 4.86 to 97.70 µg/kg, were, respectively, higher than 72% and lower than 20%. Application to spice samples available in Minas Gerais state, purchased at popular markets, showed no contamination with aflatoxin B1.

Composição e atividade antibacteriana dos óleos essenciais de Senecio crassiflorus var. crassiflorus

The essential oils of leaves, aerial and underground stems of Senecio crassiflorus var. crassiflorus were extracted by hydrodistillation and their analyses were performed by GC/MS. Qualitative and quantitative differences have been found between the analyzed parts. The main compounds of the essentials oils of the leaves were found to be oxygenated sesquiterpenes, while the oils from the aerial and underground stems showed sesquiterpene hydrocarbons as major constituents. Furthermore, the essential oils were tested against Staphylocccus aureus, Escherichia coli, Pseudomonas aeruginosa and Bacillus cereus. The essential oil of the leaves was shown to be the most active.

Flavonas, lignanas e terpeno de Piper umbellata (Piperaceae)

The phytochemical investigation of Piper umbellata leaves yielded nine compounds including one terpenoid glucoside, five flavones (vitexin 2"-O-β-glucopyranoside, apigenin 8-C-β-D-glucopyranoside,orientin 8-C-β-D-glucopyranoside,5-hydroxy-7,3',4'-trimethoxy-flavone and velutin), two lignans (sesamin e dihydrocubebin) and 4-nerolidylcathecol. Excepting 4-nerolidylcathecol, all compounds have not been described from this species yet.

Reaction mixtures formed by nitrite and selected sulfa-drugs showed mutagenicity in acidic medium

Nitrite, which is present in preserved meat and can be produced in the oral cavity by reduction of nitrate taken from vegetables, could react in stomach with nitrosatable drugs, giving genotoxic-carcinogenic N-nitroso compounds (NOC). The mutagenicity of reaction mixtures formed by sodium nitrite and selected sulfa-drugs (sulfathiazole, HST; phtalylsulfathiazole, PhST; complex Co(II)-sulfathiazole, Co(II)-ST) in acidic medium was evaluated using the Salmonella typhimurium reverse mutation assay (Ames test), with TA98 and TA 100 strains. The reactions were carried out at room temperature, with a mole ratio [nitrite]/[sulfa-drug] > 1. The three reaction mixtures showed mutagenic effects in the considered range.

Caldensinic acid, a benzoic acid derivative and others compounds from Piper carniconnectivum

A benzoic acid derivative - caldensinic acid; E-phytyl hexadecanoate; β-sitosterol and stigmasterol mixture and phaeophytin a were isolated from the aerial parts of Piper carniconnectivum. The structures of these compounds were established unambiguously by IR, MS, 1D and 2D NMR analysis.

Constituintes químicos das folhas de Senna spectabilis (DC) Irwin & Barneby var. excelsa (Schrad.) Irwin & Barneby

From leaves of Senna spectabilis var. excelsa were isolated caffeine, the triterpenes lupeol, α-amyrin, β-amyrin, cycloeucalenol, friedelin and ursolic, oleanolic and betulinic acids, besides the steroids sitosterol and stigmasterol and their respective glucosides. The structures of these compounds were established by spectroscopic analysis including two-dimensional NMR methods and comparison with published spectral data. This paper deals with the first report of these compounds in S. spectabilis var. excelsa.