ABSTRACT
The hydrodistilled oil from the fruits of Bursera tomentosa, obtained in 0.2% yield, was analyzed by GC-MS. Nine components were identified, which made up 99.3% of the oil. The most abundant constituents were cis-ocimene (47.6%), n-nonane (28.2%) and germacrene-D (11.1%). The oil showed antibacterial activity against Staphylococcus aureus (ATCC 25923), Enterococcus faecalis (ATCC 29212) and Salmonella typhi (CDC 57), with MIC values of 80 microg/mL, 120 microg/mL and 100 microg/mL, respectively.
Subject(s)
Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Bursera/chemistry , Fruit/chemistry , Oils, Volatile/pharmacology , Plant Oils/pharmacology , Oils, Volatile/chemistry , Plant Oils/chemistryABSTRACT
In this study the removal of arsenic by the Water Hyacinth (Eichhornia crassipes) and Lesser Duckweed (Lemna minor) was monitored under a concentration of 0.15mgL(-1) of the element. Plant densities were 1kg/m2 for Lesser Duckweed and 4kg/m2 for Water Hyacinth on a wet basis. The arsenic was determined in foliar tissue and water samples by hydride generation atomic absorption spectroscopy. The element was monitored as a function of time during 21 days. No significant differences were found in the bioaccumulation capability of both species. The removal rate for L. minor was 140mg As/had with a removal recovery of 5%. The Water Hyacinth had a removal rate of 600mg As/had and a removal recovery of 18%, under the conditions of the assay. The removal efficiency of Water Hyacinth was higher due to the biomass production and the more favorable climatic conditions. This specie represents a reliable alternative for arsenic bioremediation in waters.
Subject(s)
Araceae/metabolism , Arsenic/isolation & purification , Eichhornia/metabolism , Water Pollutants, Chemical/isolation & purification , Water/chemistry , Araceae/growth & development , Arsenic/analysis , Biodegradation, Environmental , Eichhornia/growth & development , Plant Leaves/chemistry , Time Factors , Water Pollutants, Chemical/analysisABSTRACT
A flow injection analysis (FIA) method was developed for the determination of pyruvate in onion cultivars (Allium cepa L.) from the West-Center region of Venezuela. The reference Schwimmer and Weston (1961) (J. Agric. Food Chem. 9 (1961) 301) Batch method was modified and adapted to FIA conditions. The formation kinetic of the 2,4-dinitrophenylhydrazine (DNPH)-pyruvate complex was evaluated at room temperature and at 37 degrees C. It was demonstrated the suitability of the chromopher formation at room temperature. The optimal values for the FIA parameters were: sample injection volume 3mL, flow rate 6mLmin(-1), reactor length 1.5m, sodium hydroxide concentration 1.0molL(-1) and hydrochloric acid concentration 0.5molL(-1). The working calibration range was extended from 80mgL(-1) (Batch method) to 700mgL(-1) with the FIA set up. The sample dilution step is thus avoided, simplifying the whole analysis process. The pungency in representative samples of the cultivars Yellow granex 438, Ultra Hybrid and Red onion "Sangre de Toro" was evaluated by the flow injection analysis (FIA)-pyruvate method and the results were compared to the reference Batch pyruvate method and to the taste panel test. Non-significant differences were found at the 95% of confidence level between the FIA method and the Batch reference method. Correlation coefficient when comparing the FIA results to the taste panel test was r(2) = 0.8353. Significant differences (P < 0.05) were found in the pungency of the cultivars, the Ultra Hybrid having the highest pungency. The pungency order from minor to major was: Red onion, Texas Grano 438 and Ultra Hybrid.
