Marco Antonio Teixeira Zullo

OIL CONTENT OF GREEN BEANS FROM SOME COFFEE SPECIES

The oil content was determined in seeds of several continental African species of the coffee germplasm bank of Instituto Agronomico de Campinas, State of Sao Paulo, Brazil. Oil was extracted from seeds with hexane in Soxhlet apparatus. Due to the economic importance, C. arabica and C. canephora have been the best studied species concerning oil content and composition, and the results obtained are in agreement with the reported in the literature. On the other hand, only one report in the literature describes the results of oil analyses in other few species of the African continent, although it does not allow comparison with our results. The oil content of most of the species varied from 9 to 15%, therefore, similar to the range observed for C. arabica and C. canephora. The exception was C. salvatrix, with 29% of oil in the seeds.

Fontes de resistência a Scrobipalpula absoluta (Meyrick, 1917) em tomateiro

Eighty-five wild and cultivated tomato accessions, being 71 Lycopersicon esculentum, 10 L. pimpinellifolium and 4 L. peruvianum, were evaluated in greenhouse, under artificial infestation, for resistance to Scrobipalpula absoluta (Meyr.) (Lepidoptera: Gelechiidae). NAV 29 and NAV 115 (L. peruvianum) showed the least foliar damage while NAV 98 (L. pimpinellifolium) was less attacked in the buds than cultivated tomatoes (L. esculentum). Then, a comparative trial was carried out among the Rio Grande and Pacesetter tomato cultivars, NAV 98 and NAV 29/115 (mixed offsprings of NAV 29 and NAV 115, because of self-incompatibility). The highest level of resistance to the pest was presented by NAV 29/115.

The SMP-buffer method for the determination of lime requirement of soils of the State of São Paulo

The SMP-buffer method for the determination of lime requirement was studied with 23 soil samples of the State of Sao Paulo. The method was calibrated against lime requirements to increase pH values to 5.5, 6.0 and 6.5 based on CaCO3 neutralization curves of the soils. A modification of the ratio of SMP-buffer to soil, which gives lower lime requirements per unit of pH depression is suggested for the use of soils that have rather low buffer capacities. The method proved to be satisfactory to predict amounts of lime needed to increase soil pH to values of 6.5, 6.0 and 5.5. Neutralization of aluminum, using a factor 1.5, increases the pH of the soils to values around 5.5.

Semisystematic nomenclature of brassinosteroids

The assignment of the trivial name to new isolated or detected brassinosteroid is based on the trivial names of seven different brassinosteroids, with names assigned according to the plant source from which they were first isolated. To avoid some observed mistakes in assigning trivial names to these compounds and the impractical constant usage of their systematic names, we propose a semisystematic nomenclature of brassinosteroids, in which (22R,23R)-2α,3α,22,23-tetrahydroxy-5α-campestane, the trivial name of which is 6-deoxocastasterone, is considered the functional parent compound and is named brassinostane or brassinane. A set of rules for naming the remaining natural brassinosteroids is presented.

Some notes on the terminology of brassinosteroids

In this paper the definitions of brassinolide, brassinolide activity andbrassins are reviewed, and definitions for the terms brassin, naturalbrassinosteroids and brassinosteroid analogues, based on biosynthetic reasoningand structure similarity are proposed.

Characterisation and properties of the inclusion complex of 24-epibrassinolide with β-cyclodextrin

This paper reports the first study of an inclusion complex of abrassinosteroid with β-cyclodextrin. The formation of inclusion complexesbetween 24-epibrassinolide and β-cyclodextrin was confirmed by theirphysicochemical properties and the compounds were analysed by differentialscanning calorimetry, powder X-ray diffraction, nuclear magnetic resonancespectrometry and scanning electron microscopy. Theoretical calculations usingthe MM+ HyperChem force field showed a preference for inclusion of thesidechain of the epibrassinolide molecule into the β-cyclodextrin cavity toform a 1:1 inclusion complex, although complexes involving inclusion ofthe steroidal nucleus also possess a favourable interaction energy. Rice laminainclination assay, employing IAC-103 and IAC-104 cultivars, showed an improvedactivity for the epibrassinolide-cyclodextrin complex compared to theepibrassinolide itself. The results suggest that brassinosteroid complexationwith cyclodextrins may enhance the biological activity of these plant growthregulators.

Ocorrência de glicoalcalóides e esverdeamento em tubérculos de batata recém-colhidos e armazenados

Thirty-six cultivars of potatoes were studied with respect to the total glycoalkaloids (TGA) content and greening capacity of the tuber. The determinations were made in the superficial portion of both newly harvested and tubers stored in the presence or absence of light during 25 days. The TGA content ranged betwen 3-24mg/100g of fresh weight. Both the storage conditions and the cultivars influenced the TGA content and greening capacity. There was a negative correlation between TGA content and the 440nm absorbance of a chloroform extract for newly harvested tubers. This correlation, however, was positive for the stored tubers. The present data suggest that both the TGA content and the greening capacity of the tubers were influenced by genetic characteristics of each cultivar.

Cytotoxicity of the phytosterol diosgenin and its derivatives in rat cultured hepatocytes and V79 fibroblasts

In this work, the cytotoxic effects of some spirostane derivatives were examined in cultured hepatocytes and V79 fibroblasts using different viability assays. The derivatives were obtained by modifying the A and B rings of diosgenin. Diosgenin and its derivatives were more toxic in V79 fibroblasts (IC50 40-300 µM) than in hepatocytes (IC50 280-1000 µM). Inhibition of cytochrome P450IIIA in cultured hepatocytes by incubation with 1 mM cimetidine did not alter the toxicity of these compounds in these cells. These observations suggest that other pathways of detoxification may be involved in hepatocytes. In conclusion, the compounds studied merit investigation for their potential pharmacological and industrial applicability.

Brassinosteróides em café

The effect of 24-epibrassinolide and 24-epicastasterone was tested in two years old Coffea arabica L cultivar Catuai Amarelo at its first yielding, in two experiments. Yield, percentage of beans with empty locus, percentage of peabeans and other parameters related to the size of the seeds were evaluated. Fruit setting was evaluated in one experiment only. It was concluded that the brassinosteroids did not affect the yield or the parameters related to the size of the seeds.

Sapogeninas esteroídicas em sisal

The hecogenin and tigogenin contents were determined in dried leaves of sisal (Agave sisalana) and of the hybrids of A. amaniensis x A. angustifolia, obtained in the Experimental Station of the Instituto Agronomico, Campinas, State of Sao Paulo, Brazil. The hybrids showed higher sapogenin contents (220-480mg/100g) than sisal (140 ± 28mg/100g), as well as higher tigogenin content (148-217mg/100g). The hybrid 003B was the only one that showed significantly higher hecogenin content (99 ± 16mg/100g) than sisal (26 ± 3mg/100g).