Marine-derived fungi: diversity of enzymes and biotechnological applications

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Metabolic activity of the sticker's lymphosarcoma

1. 1. Some parameters (glycolysis, respiration, levels of glycolytic enzymes) of the lymphoid cells from the Sticker's lymphosarcoma were established in order to better define the biochemical behavior of the venereal tumor of the dog. 2. 2. For comparative purposes lymphocytes from peripheral blood of normal tumor-bearing dogs were also studied. 3. 3. Lactic acid produced by the tumor cells during aerobic glycolysis is liberated in the reaction medium. 4. 4. Oxygen uptake is enhanced in the presence of succinate, but not with pyruvate, α-ketoglutarate, or malate as substrates. 5. 5. Higher levels of some of the enzymes from the glycolytic pathways as well as differences on the physicochemical and kinetic properties of the glycolytic regulatory enzymes are found in Sticker's tumor cells, when compared with the lymphocytes from peripheral blood of normal and tumor-bearing dogs. 6. 6. A fructose-bisphosphate positively modulated pyruvatekinase is found in the tumor cells. © 1987.

Antioxidant activity of apple extract protects against rat tongue carcinogenesis induced by 4-nitroquinoline 1-oxide

Several studies have shown that apple (Malus sp.) has many components able to exert chemopreventive activity. The aim of this study was to evaluate the chemopreventive potential of apple extract following medium-term oral carcinogenesis assay induced by 4-nitroquinoline 1-oxide (4NQO) by means of histopathological analysis and gene expression of antioxidant enzymes, such as CuZnSOD, MnSOD and catalase. A total of 30 male Wistar rats were distributed into five groups, as follows (n = 6 per group): Group 1 - negative control group (non-treated group); Group 2 - received 4NQO during 8 weeks in drinking water and treated with apple extract by gavage between the 1st and 4th weeks daily (initiation phase); Group 3 - received 4NQO for 8 weeks in drinking water and treated with apple extract by gavage between the 5th and 8th weeks daily (promotion phase); Group 4 - received apple extract by gavage for eight consecutive weeks only; and Group 5 - received 4NQO for 8 weeks in drinking water daily. Histopathological analysis revealed that apple extract protect oral lesions induced by 4NQO at initiation or promotion phase. Higher gene expression of CuZnSOD and MnSOD enzymes were noticed in groups treated with apple extract as well. Taken together, our results demonstrate that the apple extract is able to modulate medium-term oral carcinogenesis assay as a result of antioxidant activity.

Ulcer healing and mechanism(s) of action involved in the gastroprotective activity of fractions obtained from Syngonanthus arthrotrichus and Syngonanthus bisulcatus

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Peroxidase and polyphenol oxidase activity on the yield of grafted and ungrafted cucumber plants

The first experiment was carried out under green house and involved nine treatments: ‘Tsuyoi’ cucumber, ‘Shelper’ squash and ‘Green-stripped cushaw squash’ ungrafted plants and ‘Tsuyoi’ cucumber plants grafted onto ‘Shelper’ squash and ‘Green-stripped cushaw squash (lower, mid and upper region of the recommended and non-recommended rootstock, respectively). After grafting, plant tissue samples were collected 1, 4, 7, 10 and 13 days after grafting for analysis of peroxidase (EC 1.11.1.7) and polyphenol oxidase (EC 1.10.3.1) activity. In the second experiment, yield and number of marketable fruits were evaluated. The differences in peroxidase activity at the rootstock region and in polyphenol activity at the region between the scion and the rootstock seem to be determining factors for a successful grafting process, increasing the yield and the number of marketable fruits.

Control of bacterial spot of tomato and activation of enzymes related to resistance by chemicals under field conditions

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)