Carbohydrates Concentration in leaves of potato plants affected by nitrogen fertilization rates

ABSTRACT At poor conditions of nitrogen (N) in the soil, potato plants may accumulate starch in leaves and be indicative of N nutritional stress. The objective of this work was to determine the effects of N rates (0, 50, 100, 200 and 300 kg ha-1 of N) on the concentrations of carbohydrates (total soluble sugars-TSS, reducing sugars-RS, non-reducing sugars-NRS and starch) in the fourth leaf (FL) of two potato cultivars (Asterix and Atlantic) and their critical levels (CL) associated to the N fertilization rate necessary to obtain the maximum physical (MPE) and economic (MEE) efficiency of tubers. A randomized block design with four replications was used in both experiments. On day 21 after plant emergence, four FL were collected from four plants. Potatoes plants fertilized with low rates of N accumulated less TSS in leaves than those properly fertilized. The opposite occurred with content of starch. The cultivars showed similar responses to five doses of N in relation to contents of starch and TSS. However, the response to the increase in doses of N for RS, NRS and Starch/NRS is cultivar-specific. The correlations between contents of RS, NRS and Starch/NRS with the starch and TSS were dependent on the potato cultivar.

Metabolic Post-feeding Changes in Fat Body and Hemolymph of Dipetalogaster maximus (Hemiptera:Reduviidae)

Lipids and glycogen in fat body as well as the modifications in the wet weight of this organ were evaluated in an unfed insect, Dipetalogaster maximus, on day 5 after adult ecdysis (time 0) and during a 30-day period after ingestion of blood meal. Total lipids, high density lipophorin (HDLp), carbohydrates, total proteins and uric acid were determined in the hemolymph during the same period. Fat body wet weight was maximum on day 10 post-feeding and represented on day 30 only 42% of the maximum weight. Lipids stored in the fat body increased up to day 15 reaching 24% of the total weight of tissue. Glycogen was maximum on day 20, representing approximately 3% of the fat body weight. HDLp represented at all times between 17-24% of the total proteins, whose levels ranged between 35 and 47 mg/ml. Uric acid showed at 20, 25 and 30 days similar levels and significantly higher than the ones shown at days 10 and 15. Hemolymphatic lipids fluctuated during starvation between 3-4.4 mg/ml and carbohydrates showed a maximum on day 15 after a blood meal, decreasing up to 0.26 mg/ml on day 25. The above results suggest that during physiological events such as starvation, the availability of nutrients is affected, involving principally the fat body reserves

Nutritional potential of green banana flour obtained by drying in spouted bed

This study evaluated the chemical composition of peeled and unpeeled green banana Cavendish (AAA) flour obtained by drying in spouted bed, aiming at adding nutritional value to food products. The bananas were sliced and crushed to obtain a paste and fed to the spouted bed dryer (12 cm height and T = 80 ºC) in order to obtain flour. The flours obtained were subjected to analysis of moisture, protein, ash, carbohydrates, total starch, resistant starch, fiber. The green banana flours, mainly unpeeled, are good sources of fiber and resistant starch with an average of 21.91g/100g and 68.02g/100g respectively. The protein content was found in an average of 4.76g/100g, being classified as a low biological value protein with lysine as the first limiting amino acid. The results showed that unpeeled green banana flour obtained by spouted bed drying can be a valuable tool to add nutritional value to products in order to increase their non-digestible fraction.

Physiological response of vicia faba to prohexadione-calcium under saline conditions

Changes in the activities of oxidative enzymes (indole acetic acid oxidase, peroxidase and catalase), endogenous hormones (gibberellic acid (GA3), indole acetic acid (IAA), abscisic acid (ABA) and cytokinins (AsZeatin), photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids), total carbohydrates, total soluble sugars, amino acid proline and vegetative growth parameters were used as indicators to explain the physiological role of the growth retardant prohexadione-calcium on Vicia faba seedlings 40 days after sowing under salinity stress for 30 days. The obtained results show that soaking faba bean seeds prior to sowing at different concentrations of prohexadione-calcium (0, 10, 20 and 30 ppm) significantly increased the activities of indole acetic acid oxidase (IAA-oxidase) and peroxidase enzymes, but decreased the catalase enzyme activity as compared with their respective control. Application of prohexadione-Ca caused markedly decreases in the endogenous contents of gibberellins and indole acetic acid (IAA) but increased the levels of natural growth inhibitor abscisic acid (ABA) and cytokinins in the shoots of faba bean seedlings. All the prohexadione-Ca concentrations increased the contents of amino acid proline, photosynthetic pigments (chlorophyll a, chlorophyll b and carotenoids), total carbohydrates and total soluble sugars in faba bean seedlings grown under salt stress. Application of prohexadione-Ca decreased significantly seedling height and shoot fresh weight but significantly increased shoot dry weight.

Postharvest respiratory activity and changes in some chemical constituents during maturation of yellow mombin (Spondias mombin) fruit

Mature fruit from the yellow mombin (Spondias mombin) was monitored for its respiration activity. Mature green fruit from the yellow mombin was stored in closed glass chambers and the concentration of oxygen and carbon dioxide at the end of a six hour respiration period was determined. At the same interval of time, the lid of the chamber was opened for air renewal. The increase in carbon dioxide and decrease in oxygen concentration demonstrated that the fruit was climacteric. The maximum liberation of CO2 54.2 mL Kg-1 h-1 and maximum absorption of O2 49.0 mL Kg-1 h-1 occurred 186 hours after the harvest which, obviously, represented the optimum fruit quality after the senescence process started. The respiratory quotient of fruit at a climacteric maximum was 1.11 representing the oxidation of carbohydrates. Total soluble solids increased from 9.1 °Brix (initial) to 13.7 °Brix (climacteric maximum) during maturation, while the total number of acids in the fruit decreased during maturation i.e. from 1.55% initially to 1.40% at pre-climacteric, 1.0% at climacteric maximum and 0.8% in the post-climacteric stage. A similar behaviour was observed in the case of ascorbic acid. There was a continuous decrease in chlorophyll and a continuous increase in the carotenoid content of fruit during maturation.

Antioxidant capacity and chemical composition in seeds rich in omega-3: chia, flax, and perilla

The chemical composition and antioxidant capacity of five seeds, chia, golden flax, brown flax, white perilla, and brown perilla, were determined. The chemical properties analyzed included moisture, ash, crude protein, carbohydrates, total lipids, fatty acids, and antioxidant capacity (ABTS•+, DPPH•, and FRAP). The results showed the highest amounts of protein and total lipids in brown and white perilla. Perilla and chia showed higher amounts of alpha-linolenic fatty acid than those of flaxseed varieties, ranging between 531.44 mg g-1 of lipids in brown perilla, 539.07 mg g-1 of lipids in white perilla, and 544.85 mg g-1 of lipis in chia seed. The antioxidant capacity of the seeds, evaluated with ABTS•+, DPPH• , and FRAP methods, showed that brown perilla had greater antioxidant capacity when compared with white perilla, flax, and chia seeds.

Flight metabolism in Panstrongylus megistus (Hemiptera: Reduviidae): the role of carbohydrates and lipids

The metabolism of lipids and carbohydrates related to flight activity in Panstrongylus megistus was investigated. Insects were subjected to different times of flight under laboratory conditions and changes in total lipids, lipophorin density and carbohydrates were followed in the hemolymph. Lipids and glycogen were also assayed in fat body and flight muscle. In resting insects, hemolymph lipids averaged 3.4 mg/ml and significantly increased after 45 min of flight (8.8 mg/ml, P < 0.001). High-density lipophorin was the sole lipoprotein observed in resting animals. A second fraction with lower density corresponding to low-density lipophorin appeared in insects subjected to flight. Particles from both fractions showed significant differences in diacylglycerol content and size. In resting insects, carbohydrate levels averaged 0.52 mg/ml. They sharply declined more than twofold after 15 min of flight, being undetectable in hemolymph of insects flown for 45 min. Lipid and glycogen from fat body and flight muscle decreased significantly after 45 min of flight. Taken together, the results indicate that P. megistus uses carbohydrates during the initiation of the flight after which, switching fuel for flight from carbohydrates to lipids.

Foliar carbohydrates content and invertase activity in vines at São Francisco River Valley - Brazil

The irrigated agriculture at the São Francisco River Valley, Northeast Brazil, shows an increasing production of grapes for winery. Among the wines produced there the one obtained from Vitis vinifera L., cultivar Syrah, stands out due to its adaptation to the climatic conditions of the region. However, little is known about carbohydrates metabolism of vines cultivated in this region. The objective of this work was to evaluate sugar and starch contents and the invertase activity in vines leaves during two consecutive growing seasons. The experiment was carried out at Embrapa Semi-Árido and at Santa Maria Winery, respectively located in Petrolina and Lagoa Grande, Pernambuco-Brazil. Leaves were collected weekly from January to December of 2003 and assessed for reducing sugars, total soluble sugars and starch contents, as well as for acid (AI) and neutral invertases (NI). The results showed that reducing sugars, total soluble sugars and starch contents increased during fruit maturation and are influenced by temperature, radiation and insolation variations. The second growing season showed higher reducing sugars and total soluble sugars content and lower starch content in the leaves than the first one. AI activity was higher than NI activity and these also varied according to weather conditions. During berries ripening, leaves showed higher sugar content and invertase activity, suggesting a higher sugar metabolism and transport during this phase.

An in vitro analysis of the total phenolic content, antioxidant power, physical, physicochemical, and chemical composition of Terminalia Catappa Linn fruits

This study assessed the antioxidant, total phenolic, and physicochemical properties of in vitro Terminalia Catappa Linn (locally called castanhola) using the DPPH assay. The castanhola fruits had an average weight of 19.60 ± 0.00 g, combining shell, pulp, and seed weight, and a soluble solids content of 8 °Brix. The chemical composition was determined with predominance of carbohydrates (76,88 ± 0,58%).The titration method was used to determine Vitamin C content using 2,6-dichlorophenolindophenol (DCFI), known as reactive Tillmans resulting in no significant levels. Aqueous extracts of castanhola pulp showed a higher concentration of phenolics, 244.33 ± 18.86 GAE.g-1 of fruit, and alcoholic extracts, 142.84 ± 2.09 GAE.g-1 of fruit. EC50 values of the aqueous extract showed a greater ability to scavenge free radicals than the alcoholic extracts. The fruit had a significant content of phenolic compounds and high antioxidant capacity.

Reabilitação vocal pós-laringectomia total: resultados em longo prazo com prótese fonatória Blom-Singer® de longa permanência

Avaliar o uso em longo prazo de próteses fonatórias (PF) para reabilitação fonatória de pacientes submetidos à laringectomia total (LT). Foram estudados a influência do tempo de realização da punção tráqueo-esofágica (PTE), o uso de radioterapia pós-operatória (RTXpos-op), idade e seguimento do paciente, sobre a taxa de sucesso de uso da PF. FORMA DE ESTUDO: Clínico prospectivo. MATERIAL E MÉTODOS: Setenta e um pacientes submetidos à LT e reabilitados com PF de longa permanência. Todos foram avaliados por otorrinolaringologista e fonoaudióloga, quanto aos aspectos funcionais vocais, durante o seguimento. Os dados relativos a tempo de colocação da PF, tempo de utilização da PF, uso de RTXpos-op, idade do paciente, tempo de seguimento e tempo de duração de cada PF foram anotados. RESULTADOS: Houve 87% de pacientes com PTE primária e 13% com secundária. O tempo de seguimento variou de 12 a 87 meses, com média de 38 meses para a PTE primária e 51 meses para a secundária. Houve 59% de pacientes submetidos a RTXpos-op. A taxa de sucesso geral foi de 94%. Na PTE primária foi de 97% e na secundária 78% (p=0,07) e, após dois anos, foi de 96% na PTE primária e 75% na secundária (p=0,07). Utilização de RTXpos-op e idade do paciente não influenciaram no sucesso de utilização de PF, independentemente do tempo de seguimento. CONCLUSÕES: Houve tendência de maior sucesso na reabilitação vocal de pacientes submetidos à LT com a PTE primária. O uso de RTXpos-op e idade não influenciou nesta taxa de sucesso.

Recorrência na área do traqueostoma após laringectomia total

O desenvolvimento da recorrência na área do traqueostoma em pacientes laringectomizados é uma das evoluções mais sérias do carcinoma epidermóide de laringe. Os fatores mais comumente associados a esta patologia são a extensão infraglótica do tumor laríngeo e a traqueostomia prévia à laringectomia. OBJETIVO: Identificar achados de exame clínico de pacientes laringectomizados relacionados com a possível gênese desta recorrência. FORMA DE ESTUDO: Estudo descritivo retrospectivo. CASUÍSTICA E MÉTODOS: Foram analisados 47 pacientes laringectomizados em nosso hospital devido ao carcinoma epidermóide de laringe entre 1995 e 2004 e avaliado o número de recorrências, bem como os fatores de risco relacionados. RESULTADOS: A recorrência na área do traqueostoma desenvolveu-se em cinco (10,6%) destes pacientes. Não houve correlação estatística entre a invasão infraglótica do tumor ou traqueostomia prévia com a recorrência na área do traqueostoma. CONCLUSÃO: A recorrência na área do traqueostoma continua sendo uma das evoluções fatais do câncer laríngeo, não sendo possível neste estudo identificar fatores relacionados com esta recorrência. Novos estudos com casuísticas maiores e longos períodos de seguimento são necessários no futuro para melhor compreensão desta patologia.

Reabilitação fonatória do laringectomizado total: utilização de toxina botulínica na voz tráqueo-esofágica com prótese fonatória

Na punção tráqueo-esofágica(PTE) é realizada miotomia do músculo constritor da faringe, mas sua necessidade é entre 9% a 79% dos pacientes. Sua realização pode aumentar as taxas de fístula salivar no pós-operatório. A aplicação da TB é ambulatorial. OBJETIVO: Análise da eficácia da aplicação de toxina botulínica (TB), na reabilitação do laringectomizado total com voz tráqueo-esofágica(VTE) com espasmo(E) do segmento faringo-esofágico (SFE) sem miotomia. MATERIAL E MÉTODOS: Análise de oito pacientes submetidos à laringectomia total (LT), reabilitados com VTE com prótese fonatória (PF), esforço para emissão de voz devido à E do SFE. Todos submetidos a tratamento dessa alteração motora com injeção de 100 unidades de TB no SFE. A avaliação constituiu-se de análise perceptiva de voz, videofluoroscopia (VF) do SFE, análise acústica de voz e manometria computadorizada (MC) do SFE, todos antes e após aplicação de TB. DESENHO DE ESTUDO: Estudo prospectivo. RESULTADOS: Houve diminuição na pressão à MC do SFE, após a injeção de TB. Análise acústica demonstrou melhora na qualidade de harmônicos após o tratamento. Houve emissão de voz sem esforço e melhora do E após o uso da TB. CONCLUSÃO: Todos os pacientes com E do SFE apresentaram melhora vocal após aplicação da TB neste SFE.

Comparison of different methods for the determination of total organic carbon and humic substances in Brazilian soils

ABSTRACTAiming to compare three different methods for the determination of organic carbon (OC) in the soil and fractions of humic substances, seventeen Brazilian soil samples of different classes and textures were evaluated. Amounts of OC in the soil samples and the humic fractions were measured by the dichromate-oxidation method, with and without external heating in a digestion block at 130 °C for 30 min; by the loss-on-ignition method at 450 °C during 5 h and at 600 °C during 6 h; and by the dry combustion method. Dry combustion was used as reference in order to measure the efficiency of the other methods. Soil OC measured by the dichromate-oxidation method with external heating had the highest efficiency and the best results comparing to the reference method. When external heating was not used, the mean recovery efficiency dropped to 71%. The amount of OC was overestimated by the loss-on-ignition methods. Regression equations obtained between total OC contents of the reference method and those of the other methods showed relatively good adjustment, but all intercepts were different from zero (p < 0.01), which suggests that more accuracy can be obtained using not one single correction factor, but considering also the intercept. The Walkley-Black method underestimated the OC contents of the humic fractions, which was associated with the partial oxidation of the humin fraction. Better results were obtained when external heating was used. For the organic matter fractions, the OC in the humic and fulvic acid fractions can be determined without external heating if the reference method is not available, but the humin fraction requires the external heating.