Indole ring oxidation by activated leukocytes prevents the production of hypochlorous acid

Hypochlorous acid (HOCl) released by activated leukocytes has been implicated in the tissue damage that characterizes chronic inflammatory diseases. In this investigation, 14 indole derivatives, including metabolites such as melatonin, tryptophan and indole-3-acetic acid, were screened for their ability to inhibit the generation of this endogenous oxidant by stimulated leukocytes. The release of HOCl was measured by the production of taurine-chloramine when the leukocytes (2 x 10(6) cells/mL) were incubated at 37ºC in 10 mM phosphate-buffered saline, pH 7.4, for 30 min with 5 mM taurine and stimulated with 100 nM phorbol-12-myristate acetate. Irrespective of the group substituted in the indole ring, all the compounds tested including indole, 2-methylindole, 3-methylindole, 2,3-dimethylindole, 2,5-dimethylindole, 2-phenylindole, 5-methoxyindole, 6-methoxyindole, 5-methoxy-2-methylindole, melatonin, tryptophan, indole-3-acetic acid, 5-methoxy-2-methyl-3-indole-acetic acid, and indomethacin (10 µM) inhibited the chlorinating activity of myeloperoxidase (MPO) in the 23-72% range. The compounds 3-methylindole and indole-3-acetic acid were chosen as representative of indole derivatives in a dose-response study using purified MPO. The IC50 obtained were 0.10 ± 0.03 and 5.0 ± 1.0 µM (N = 13), respectively. These compounds did not affect the peroxidation activity of MPO or the production of superoxide anion by stimulated leukocytes. By following the spectral change of MPO during the enzyme turnover, the inhibition of HOCl production can be explained on the basis of the accumulation of the redox form compound-II (MPO-II), which is an inactive chlorinating species. These results show that indole derivatives are effective and selective inhibitors of MPO-chlorinating activity.

Anticoccidial effects of acetic acid on performance and pathogenic parameters in broiler chickens challenged with Eimeria tenella

The objective of the present study was to evaluate the anticoccidial effect of the different concentrations of the acetic acid in the broiler chickens in comparison with the amprolium anticoccidial. A total of 198 chicks were placed 11 per pen with three pens per treatment. The different concentrations (1%, 2% and 3%) of acetic acid and amproilum (at the dose rate of 125ppm) were given to the experimental groups in drinking water from 10-19th days of age. One group was kept as infected non medicated control and one as non infected non medicated control. All the groups were inoculated orally with 75,000 sporulated oocysts at the 12th day of age except non infected non medicated control. Anticoccidial effect was evaluated on the basis of performance (weight gain, feed conversion ratio) and pathogenic (oocyst score, lesion score and mortality %age) parameters. Among acetic acid medicated groups, the maximum anticoccidial effect was seen in the group medicated with 3% acetic acid followed by 2% and 1% acetic acid medicated groups. Amprolium and 3% acetic acid were almost equivalent in suppressing the negative performance and pathogenic effects associated with coccidiosis (Eimeria tenella) challenge. In summary, acetic acid has the potential to be used as alternative to chemotherapeutic drugs for Eimeria tenella control. Concentration-dependent anticoccidial effect of acetic acid suggests that further studies should be carried out to determine the possible maximum safe levels of acetic acid with least toxic effects to be used as anticoccidial.

The influence of light spectra, UV-A, and growth regulators on the in vitro seed germination of Senecio cineraria DC.

This study was carried out to investigate the effects of light spectra, additional UV-A, and different growth regulators on the in vitro germination of Senecio cineraria DC. Seeds were surface-sterilized and inoculated in MS medium to evaluate the following light spectra: white, white plus UV-A, blue, green, red or darkness. The maximum germinability was obtained using MS0 medium under white light (30%) and MS + 0.3 mg L-1 GA3 in the absence of light (30.5%). S. cineraria seeds were indifferent to light. Blue and green lights inhibited germination. Different concentrations of gibberellic acid (GA3) (0.1; 0.4; 0.6; 0.8; 1.0 and 2.0 mg L-1) and indole-3-acetic acid IAA (0.1; 0.3 and 1.0 mg L-1) were evaluated under white light and darkness. No concentration of GA3 enhanced seed germination percentage under white light. However, when the seeds were maintained in darkness, GA3 improved germination responses in all tested concentrations, except at 1.0 mg L-1. Under white light, these concentrations also increased the germination time and reduced germination rate. Germination rate, under light or darkness, was lower using IAA compared with GA3.

Diversity and capacity to promote maize growth of bacteria isolated from the Amazon region

ABSTRACT Maize plants can establish beneficial associations with plant growth-promoting bacteria. However, few studies have been conducted on the characterization and inoculation of these bacteria in the Amazon region. This study aimed to characterize endophytic bacteria isolated from maize in the Amazon region and to assess their capacity to promote plant growth. Fifty-five bacterial isolates were obtained from maize grown in two types of ecosystems, i.e., a cerrado (savanna) and a forest area. The isolates were characterized by the presence of the nifH gene, their ability to synthesize indole-3-acetic acid (IAA) and solubilize calcium phosphate (CaHPO4), and 16S rRNA partial gene sequencing. Twenty-four bacteria contained the nifH gene, of which seven were isolated from maize plants cultivated in a cerrado area and seventeen from a forest area. Fourteen samples showed the capacity to synthesize IAA and only four solubilized calcium phosphate. The following genera were found among these isolates: Pseudomonas; Acinetobacter; Enterobacter; Pantoea; Burkholderia and Bacillus. In addition, eight isolates with plant growth-promoting capacity were selected for a glasshouse experiment involving the inoculation of two maize genotypes (a hybrid and a variety) grown in pots containing soil. Inoculation promoted the development of the maize plants but no significant interaction between maize cultivar and bacterial inoculation was found. A high diversity of endophytic bacteria is present in the Amazon region and these bacteria have potential to promote the development of maize plants.

Leaf and root volatiles produced by tissue cultures of Alpinia zerumbet (pers.) Burtt & Smith under the influence of different plant growth regulators

Volatiles produced by plantlets of Alpinia zerumbet were obtained by means of simultaneous distillation-extraction (SDE). The effects of indole-3-acetic acid, kinetin, thidiazuron and 6-benzylaminopurine on leaf and root volatile composition obtained by tissue cultures were investigated. A higher content of b-pinene and a lower content of sabinene were observed in leaf volatile of plantlets cultured in control, IAA and IAA+ TDZ media, as compared with those of donor plants. In vitro conditions were favorable to increase caryophyllene content. Volatile compounds from the root were characterized mainly by camphene, fenchyl-acetate and bornyl acetate; which constitute about 60% of total volatile.

MICROPROPAGATION AND ACCLIMATIZATION OF Aegiphila verticillata Vell.: AN ENDANGERED WOODY SPECIES

The objective of this work was to establish an efficient protocol for in vitro multiplication and rooting, as well as ex vitroacclimatization of Aegiphila verticillata, a woody species found in Brazilian rocky fields. Aseptic cultures were established by seeds and two multiplication analyses were performed. In the first, we employed 6-benzylaminopurine (BAP – 0, 2.5, 5 and 7.5 μM) + α-naphthalene acetic acid (NAA – 0, 0.2, 0.4 and 0.6 μM) and, in the second, were studied adenine sulfate, kinetin and thidiazuron (0, 5, 7.5, 10 and 12.5 μM). After 90 days, we assessed the quantitative and qualitative shoot propagation. There were more than 90% seed germination and low contamination (2%). In multiplication phase, the culture medium that promoted the best quantitative and qualitative culture development was supplemented with 7.5 μM BAP + 0.4 μM NAA. In the rooting assay, were used NAA, indole-3-acetic acid (IAA) and indole-3-butyric acid (IBA) (0, 0.1, 0.2, 0.3 or 0.4 μM). After 90 days, the root number and rooting quality were evaluated. In this analysis, differences were not found between the control and the other treatments. Rooted plantlets were acclimatized in styrofoam trays for 30 days, after which they were transferred to pots in the greenhouse. Only 3% of the plants subjected to initial acclimatization died and 70% of the plants transferred to the field conditions survived and showed normal development. The results founded in this work are the first involving in vitro propagation and ex vitroacclimatization of Aegiphila verticillata and provide a continuous supply of this medicinal native species, endangered due anthropogenic activities.

Sinningia allagophylla(Gesneriaceae): in vitro cultivation of a native plant of the Brazilian cerrado

We used axillary buds as initial explants for hormone interaction studies required for in vitro cultivation of S. allagophylla. Callus production was achieved on gelled Murashige & Skoog medium (MS) supplemented with indole-3-acetic acid (IAA= 0.1 and 0.5 mg.l­1 alone or combined with 6 benzylaminopurine) (BA= 0.01 and 0.1 mg.l-1). A hormone balance between IAA and BA that would encourage shoot bud development was not found. Nodal segments from axenic cultures grown in the presence of cytokinin (0.1 mg.1­1 of BA) without any auxin on MS medium with half-strength macronutrients were used as a standard explant source for subsequent experiments on optimum mineral culture media composition for S. allagophylla in vitro cultivation. We found that explants kept in vitro on gelled Gamborg et al. (B5) mineral composition culture medium showed better shoot and specially root growth than on MS medium. Comparisons of the ammonium and nitrate ratios of MS and B5 media indicate that B5 medium has a substantial reduced ammonium ion when compared to MS medium, as well as a lower total nitrogen level. The growth response pattern obtained in vitro may be evidence of the adaptation of this species to soils of poor mineral composition as found in the Brazilian cerrado, as well as an indication that nitrogen levels play a key role for S. allagophylla growth.

Effect of acetic acid on rice seeds coated with rice husk ash

Flooded rice cultivation promotes anaerobic conditions, favoring the formation of short chain organic acids such as acetic acid, which may be toxic to the crop. The objective of this study was to evaluate the effect of acetic acid on rice seeds coated with rice husk ash. The experiment was arranged in a 2 x 5 x 5 factorial randomized design, with two cultivars (IRGA 424 and BRS Querência), five doses of coating material (0, 2, 3,4 e 5 g kg-1 seed) and five concentrations of acetic acid (0, 3, 6, 9 and 12 mM), with 4 replications, totaling 50 treatments. The variables first count of germination, germination, shoot and root length, dry weight of shoots and roots were recorded. The results showed that coating rice seeds with rice husk ash up to 5 g kg-1 seed does not influence the performance of rice seeds of cultivars IRGA 424 and BRS Querência when exposed to concentrations of 12 mM acetic acid. The presence of acetic acid in the substrates used for seed germination reduced the vigor and viability of seeds of cultivars IRGA 424 and BRS Querência, as well as seedling development, affecting mainly the roots of BRS Querência.

Rice straw incorporated just before soil flooding increases acetic acid formation and decreases available nitrogen

Incorporation of rice straw into the soil just before flooding for water-seeded rice can immobilize mineral nitrogen (N) and lead to the production of acetic acid harmful to the rice seedlings, which negatively affects grain yield. This study aimed to evaluate the formation of organic acids and variation in pH and to quantify the mineral N concentration in the soil as a function of different times of incorporation of rice straw or of ashes from burning the straw before flooding. The experiment was carried out in a greenhouse using an Inceptisol (Typic Haplaquept) soil. The treatments were as follows: control (no straw or ash); incorporation of ashes from previous straw burning; rice straw incorporated to drained soil 60 days before flooding; straw incorporated 30 days before flooding; straw incorporated 15 days before flooding and straw incorporated on the day of flooding. Experimental units were plastic buckets with 6.0 kg of soil. The buckets remained flooded throughout the trial period without rice plants. Soil samples were collected every seven days, beginning one day before flooding until the 13th week of flooding for determination of mineral N- ammonium (NH4+) and nitrate (NO3-). Soil solution pH and concentration of organic acids (acetic, propionic and butyric) were determined. All NO3- there was before flooding was lost in approximately two weeks of flooding, in all treatments. There was sigmoidal behavior for NH4+ formation in all treatments, i.e., ammonium ion concentration began to rise shortly after soil flooding, slightly decreased and then went up again. On the 91st day of flooding, the NH4+ concentrations in soil was 56 mg kg-1 in the control treatment, 72 mg kg-1 for the 60-day treatment, 73 mg kg-1 for the 30-day treatment and 53 mg kg-1 for the ash incorporation treatment. These ammonium concentrations correspond to 84, 108, 110 and 80 kg ha-1 of N-NH4+, respectively. When the straw was incorporated on the day of flooding or 15 days before, the concentration of N-NH4+ in the soil was 28 and 54 mg kg-1, equivalent to an accumulation of 42 and 81 kg ha-1 of N-NH4+, respectively. There was formation of acetic acid in which toxic concentrations were reached (7.2 mmol L-1) on the 15th day of flooding only for the treatment with straw incorporated on the day of flooding. The pH of the soil solution of all the treatments increased after flooding and this increase was faster in the treatments with incorporation of straw, followed by the ash treatment and then the control. After 60 days of flooding, however, the pH values were around 6.5 for all treatments, except for the control, which reached a pH of 6.3. Rice straw should be incorporated into the soil at least 30 days before flooding; otherwise, it may immobilize part of the mineral N and produce acetic acid in concentrations toxic to rice seedlings.

Acetic acid as an intervention strategy to decontaminate beef carcasses in mexican commercial slaughterhouse

Beef can be contaminated during the slaughter process, thus other methods, besides the traditional water washing, must be adopted to preserve meat safety. The objective of this study was to evaluate the effect of 2% acetic acid interventions on the reduction of indicator bacteria on beef carcasses at a commercial slaughterhouse in Mexico. Reduction was measured by the count of mesophilic aerobic bacteria (TPC), total coliform (TC), and fecal coliform (FC) (log CFU/ cm²). Among the different interventions tested, treatments combining acetic acid solution sprayed following carcass water washing had greater microbial reduction level. Acetic acid solution sprayed at low pressure and longer time (10-30 psi/ 60 s) reached higher TPC, TC, and FC reductions than that obtained under high pressure/ shorter time (1,700 psi/ 15 s; P<0.05). Exposure time significantly affected microbial reduction on carcasses. Acetic acid solution sprayed after carcass washing can be successfully used to control sources of indicator bacteria on beef carcasses under commercial conditions.

GROWTH, YIELD AND POSTHARVEST QUALITY OF WAX APPLE AS AFFECTED BY NAPHTHALENE ACETIC ACID APPLICATION

Results of this study represent the first report of the effect of Naphthalene Acetic Acid (NAA) on the pre and post harvest quality of wax apple fruit. The wax apple trees were spray treated with 0, 5, 10 and 20 mg L-1 NAA under field conditions during 2008 to 2011. The experiments were carried out in Completely Randomized Design (CRD) with six replications. Leaf chlorophyll content, chlorophyll fluorescence, photosynthetic yield, net photosynthetic rate, drymatter content of leaves and total soluble solids and K+content of wax apple fruits were significantly increased after treatments with 10 mg L-1. Polygalacturonase activity significantly decreased with NAA treatments. The application of 5 mg L-1 NAA increased 27% more bud and reduced 42% less fruit drop compared to the control. In addition, higher protein and phosphate synthase activity of leaves, fruit set, fruit growth, larger fruit size and yield were recorded in NAA treated plants. In storage, treated fruits exhibited higher TSS and firmness and less weight loss, browning, titratable acidity, respiration and ethylene production than the control. It is concluded that spraying with 5 and 10 mg L-1 NAA once a week under field conditions produced better fruit growth and yield of the wax apple and maintained better fruit quality in postharvest storage.

Influence of preoperative supplementation of omega-3 fatty acid in the healing of colonic anastomoses in malnourished rats receiving paclitaxel

OBJECTIVE: To evaluate the effect of preoperative supplementation of omega-3 fatty acids on the healing of colonic anastomoses in malnourished rats receiving paclitaxel. METHODS: we studied 160 male Wistar rats, divided in two groups: one subjected to malnutrition by pair feeding (M) for four weeks, and another that received food ad libitum (W). In the fourth week, the groups were further divided into two subgroups that received omega-3 or olive oil by gavage. The animals were submitted to colonic transection and end-to-end anastomosis. After the operation, each of the four groups was divided into two subgroups that received intraperitoneal isovolumetric solutions of saline or paclitaxel. RESULTS: mortality was 26.8% higher in the group of animals that received paclitaxel (p = 0.003). The complete rupture strength was greater in well-nourished-oil Paclitaxel group (WOP) compared with the the malnourished-oil Paclitaxel one (MOP). The collagen maturation index was higher in well-nourished-oil saline group (WOS) in relation to the malnutrition-oil-saline group (MOS), lower in malnourished-oil-saline group (MOS) in relation to malnourished-ômega3-saline one (M3S) and lower in the well-nourished-omega3-saline group (W3S) compared with the malnourished-omega3-saline (M3S). The blood vessel count was higher in the malnourished-oil-saline group (MOS) than in the malnourished-oil-paclitaxel group (MOP) and lower in the malnourished-oil-saline group (MOS) in relation to the malnourished-omega3-paclitaxel group (M3P). CONCLUSION: supplementation with omega-3 fatty acids was associated with a significant increase in the production of mature collagen in malnourished animals, with a reversal of the harmful effects caused by malnutrition associated with the use of paclitaxel on the rupture strength, and with a stimulus to neoangiogenesis in the group receiving paclitaxel.

Gene transfer of Chlorella vulgaris n-3 fatty acid desaturase optimizes the fatty acid composition of human breast cancer cells

Chlorella vulgaris has the gene of n-3 fatty acid desaturase (CvFad3), which can synthesize the precursor of n-3 polyunsaturated fatty acids (PUFAs) or convert n-6 to n-3 PUFAs. The objective of the present study was to examine whether the CvFad3 gene from C. vulgaris can be functionally and efficiently expressed in human breast cancer cells and whether its expression can exert a significant effect on cell fatty acid composition. We inserted the CvFad3 gene into the plasmid pEGFP-C3 to construct the eukaryotic expression vector pEGFP-C3-n-3 and to express the n-3 Fad gene in human breast cancer cells (MCF-7 cells). Transfection of MCF-7 cells with the recombinant vector resulted in a high expression of n-3 fatty acid desaturase. Lipid analysis indicated that the ratio of n-6/n-3 PUFAs was decreased from 6:1 in the control cells to about 1:1 in the cells expressing the n-3 fatty acid desaturase. Accordingly, the CvFad3 gene significantly decreased the ratio of n-6/n-3 PUFAs of the MCF-7 cell membrane. The expression of the CvFad3 gene can decrease cell proliferation and promote cell apoptosis. This study demonstrates that the CvFad3 gene can dramatically balance the ratio of n-6/n-3 PUFAs and may provide an effective approach to the modification of the fatty acid composition of mammalian cells, also providing a basis for potential applications of its transfer in experimental and clinical settings.

Tissue culture parameters in sweet orange cultivars

The objective of this work was to establish tissue culture parameters for gene transfer in sweet orange cultivars. Epicotyl explants with different ages were cultured with 6-benzylaminopurine (BAP), kanamycin and hygromycin. Shoots were cultured with alpha-naphthaleneacetic acid (NAA) alone or in combination with indole-3-butyric acid (IBA). The requirement of BAP for shoot development was genotype-specific. Epicotyl explants from 35-day-old seedlings produced significantly more shoots per explant in 'Pêra'. Kanamycin inhibited shoot regeneration for the most cultivars. The percentage of shoots that produced roots in 'Pêra' was significantly higher in medium with NAA and IBA than with NAA alone.

VEGETATIVE RESCUE AND CUTTINGS PROPAGATION OF Araucaria angustifolia (Bertol.) Kuntze

Brazilian pine or araucaria (Araucaria angustifolia) is a coniferous tree with great economic, social and environmental importance in southern Brazil, being exploited for both wood production and for its edible pine nuts. However, no efficient cloning techniques are available and, therefore, the purpose of this study was to evaluate the effectiveness of vegetative rescue methods for cuttings propagation of the species. Shoots/cuttings were generated in two ways: 26 years old trees underwent coppicing and 20 years old trees had the primary branches on the upper third of crown pruned at 2, 20 and 50 cm from the main trunk. Orthotropic shoots were rooted after application of indole-3-butyric acid (IBA) at 0, 2, 4 and 6 g.L-1. Coppicing produced 47 cuttings per plant with 90% orthotropic shoots, while pruning resulted in 182 cuttings per plant with 44% orthotropic shoots. Rooting success indexes were low with no influence of IBA, although they are slightly superior to the ones available in the literature for the species, ranging from 12 to 30% for the coppice shoots and from 0 to 28% for the branches shoots. We conclude that both vegetative rescue techniques are viable and have potentially important applications. Coppicing is recommended for the propagation aiming the production of wood, while shoots derived from the side branches of the crown are more appropriate for seeds orchards formation.