Nutritional quality of lupine (Lupinus albus cv. Multolupa) as affected by lactic acid fermentation.

The effects of selected NRRL strains of Lactobacillus acidophilus, L. buchneri, L. cellobiosus and L. fermentum upon oligosaccharide, phytate and alkaloid contents, as well as on the nutritive value of lupine, were investigated. Lupine was processed to a 12% total solids suspension, inoculated with 1% (v/v) cultures and fermented until a final desired pH of 4.5. L. acidophilus B-2092 and L. buchneri B-1837 growth was related to a significant sucrose breakdown and decreases of phytates, whereas L. acidophilus B-1910 and L. fermentum B-585 reduced the content of flatulence oligosaccharides. The activity of L. acidophilus B-1910 was particularly associated with lowering of alkaloids and increase of riboflavin. Lactic acid fermentation produced slight changes in lysine and methionine contents. No significant differences in net protein ratio values and protein digestibility were found between fermented and unfermented lupine (P less than 0.05). A 1:1 ratio mixture of B-1910 and B-2092 strains of L. acidophilus lead to a final fermented lupine with nutritional advantages to those given by the individual cultures.

Liquid chromatography with amperometric detection of some sulphonamides and their N4-acetyl-metabolites in serum and urine.

Sulphonamides separated on a C18 LC column were detected at lower levels using amperometric detection at a glassy carbon electrode in comparison with UV detection at 258 nm. Whereas sulphonamides are detectable at a potential of +1.00 V, their N4-acetyl-metabolites required a potential of +1.25 V to be detected after their separation by LC. An interference commonly present in serum and urine, which co-eluted with one of the analytes, was detected at 1.25 V. This was overcome with an appropriate sample preparation in which 150 microliters of serum or 75 microliters of urine were first diluted to 1.5 ml with phosphate buffer (pH 3.0; 0.2 M). A 1.0 ml volume of this solution was then passed through an Extrelut 1 column. The analytes were eluted with dichloromethane, which was evaporated under vacuum, and redissolving the analytes in an appropriate volume of mobile phase, i.e. methanol-phosphate buffer (pH 6.7; 0.067 M) (25:75, v/v). For sulphamethoxazole (SMX) and sulfamethoxypyridazine (SMP) and their N4-acetyl-metabolites the calibration curves were linear between 1.5 x 10(-7) and 8 x 10(-6) M. The recovery ranged between 92.6 and 97.6% in serum and between 80.5 and 99.4% in urine. Detection limits were 10 times lower with amperometric detection than with UV detection. The method has been applied to the quantitation of SMX and SMP and their N4-acetyl-metabolites in serum and urine after their oral administration.

Tribromophenol and pentachlorophenol uptake from sawdust to horticultural products.

This paper presents a study of the uptake of 2,4,6-tribromophenol (TBP), pentachlorophenol (PCP), and its metabolite pentachloroanisole (PCA) from contaminated sawdust from the forest industry in horticultural products such as apples, raspberries, and fodder maize for cattle feed. The samples were obtained from Bio-Bio Province in South Chile between 2002 and 2006. The analytical parameters of the methodology applied to the different matrices are presented and discussed. The chromatographic method was applied to determine the residues in 413 horticultural product samples. Eleven per cent of fodder maize samples showed detectable or quantifiable levels of PCP, TBP or PCA, 3% of samples presented quantifiable levels, although the concentrations surpassed the maximum allowed concentrations for vegetables (>10 microg kg(-1)) in only two samples. Traces of TBP were detected in eight samples, PCA was detected in 15, and PCP in 14 samples. Based on these results, a risk analysis was performed, indicating a low probability, 0.4% for PCA, 1.6% for TBP and 1.9% for PCP, to find concentrations higher than the allowed maximum. For apples and raspberries, no residues of these compounds were detected. These results indicate that those cultivars directly exposed to sawdust, like fodder maize, could contain detectable residues in several samples. To confirm this observation, a field assay was performed on fodder maize cultivated in the presence of sawdust artificially contaminated with 30 mg of TBP and/or PCP under controlled conditions. The results showed that under the experimental conditions used in the study, TBP can be transferred from sawdust to the plant, with an uptake rate of 0.04% from the TBP applied initially with sawdust but not to the corn ear. Also, the degradation of PCP to PCA was observed in the soil.

Relevance of chromatographic efficiency in varietal authenticity verification of red wines based on their anthocyanin profiles: Interference of pyranoanthocyanins formed during wine ageing.

The determination of the grape variety of aged red wines based on the ratio of acetylated and coumaroylated anthocyanins (R(ac/coum)) can be influenced by the formation of pyranoanthocyanins. Coelution of the pyranoanthocyanin pinotin A and the 3-coumaroylglucoside of malvidin can affect the obtained data for the R(ac/coum) values, which in turn could lead to a false classification of wine variety and rejection of the wines by the food authorities. Investigations using different reversed phase high performance liquid chromatography columns demonstrate the importance of a good chromatographic resolution of these analytes.

[Indoor air pollution in southeast Santiago, Chile]. / Contaminación aérea intradomiciliaria en el área sur-oriente de Santiago.

BACKGROUND: Indoor air pollution could play an important role in the susceptibility to respiratory diseases of vulnerable individuals, such as elders and infants. AIM: To evaluate indoor air pollution in a low income population of South East Santiago. SUBJECTS AND METHODS: A domiciliary survey of contaminant sources was carried out in the bouses of a cohort of 522 children less than one year old. Using a case-control design, 121 children consulting for respiratory diseases were considered as cases and 131 healthy infants of the same age and sex were considered as controls. In the houses of both groups, active monitors for particulate matter (PM10) and passive monitors for NO2 were installed. RESULTS: Forty two percent of fathers and 30% of mothers were smokers, and in two thirds of the families there was at least one smoker. Eighty five percent used portable heaters in winter. Of these, 77% used kerosene as fuel. Only 27% had water heating appliances. The rest heated water on the kitchen store or on bonfires. Most kitchen stoves used liquid gas as fuel. Twenty four hour PM10 was 109 +/- 3.2 micrograms/m3. Mean indoor and outdoor NO2 in 24 h was 108 +/- 76.3 and 84 +/- 53.6 micrograms/m3 respectively. Indoor NO2 levels were related to the use of heating devices and smoking. No differences in PM10 and NO2 levels were observed between cases and controls. CONCLUSIONS: There is a clear relationship between indoor pollution and contaminating sources. Indoor NO2 levels are higher than outdoors.

Source apportionment of urban particulate aliphatic and polynuclear aromatic hydrocarbons (PAHs) using multivariate methods.

Samples of organic aerosol were collected in Santiago de Chile. An activated-charcoal diffusion denuder was used to strip out organic vapors prior to particle collection. Both polynuclear aromatic hydrocarbons (PAHs) and aliphatic hydrocarbons were determined using gas chromatography/mass spectrometry (GC/MS). Organic particle sources were resolved using both concentration diagnostic ratios and multivariate methods such as hierarchical cluster analysis (HCA) and factor analysis (FA). Four factors were identified based on the loadings of PAHs and n-alkanes and were attributed to the following sources: (1) high-temperature combustion of fuels; (2) fugitive emissions from oil residues; (3) biogenic sources; and (4) unburned fuels. Multilinear regression (MLR) analysis was used to determine emission profiles and contributions of the sources. The reconstructed concentrations of particle phase aliphatic and polynuclear aromatic hydrocarbons were in good agreement (R2 > 0.70) with those measured in Santiago de Chile.