CORRELATION AMONG METALLIC IONS,PHENOLIC COMPOUNDS AND ANTIMICROBIAL ACTION IN MEDICINAL PLANTS EXTRACTS

ABSTRACT

The extracts of three different medicinal plants –Calendula officinalis L., Maytenus ilicifolia Martius ex Reissek and Cymbopogon citratus (DC) Stapf – obtained with 70% and 95% v/v ethanol had their antimicrobial activity tested against five pathogenic microorganisms. A quantitative analysis of total phenols, flavonoids and mineral species was performed on the extracts using UV‐vis spectroscopy and atomic absorption spectroscopy. Klebsiella pneumoniae showed the greatest sensibility to the extracts tested. The mineral content of the medicinal herbs varied according to the type of plant (Cu = not detected to 10.90; Zn = 0.85 to 10.04; Na = 24.94 to 153.62; Al = 90.04 to 420.39; Mg = 9.62 to 1,129.15; Ca = 7.15 to 167.27 and K = 913.85 to 9,578.94 µg/g); however, the concentration of heavy elements (Pb, Cd and Cr) was null in the extracts. The concentrations of flavonoids ranged from 13.55 to 41.54 mg/g and 92.35 to 518.28 mg/g for phenolic acids.

PRACTICAL APPLICATIONS

The use of plants with pharmacological activities has increased significantly because of their functional properties in the diet for the promotion of human health and antimicrobial effects. Moreover, medicinal herbs play an important role in public health, especially in developing countries. In Brazil, the use of plant extracts in the treatment of certain diseases is very common. This habit can be explained, at least in part, by the belief that herbs with therapeutic effects do not have toxic effects on the organism. In this paper, ethanolic extracts of three medicinal plants, widely cultivated and used by the population of Brazil and worldwide, had their levels of metals ions and total phenolic compounds determined. Antimicrobial activity of the extracts was evaluated against foodborne pathogens or food spoilage organisms or clinically isolates microorganisms.

     

PHYSICAL AND CHEMICAL CHANGES IN VACUUM PACKAGED PARMIGIANO REGGIANO CHEESE DURING STORAGE AT 25, 2 AND −25C

Parmigiano Reggiano (PR) cheese, packed in single 20g portions under vacuum, was stored at three different temperatures (25C, 2C and ?25C) to evaluate chemical and physical changes in the product during 120 days of storage. There was no increase in lipid oxidation, even though the presence of pentane in the head space showed that the PR samples were already slightly oxidized following the 18 months of ripening process. Color and water activity determinations led to the hypothesis that the lipid fraction migrated to the sample surface when stored at 25C. Other changes observed by the authors influenced the modification of the flavor and a decrease in the overall acceptance of the PR samples packed under vacuum and stored at room temperature. However, they did not seem to be related to lipid oxidation.     

Gate sizing using geometric programming

A two-step transistor sizing optimization method based on geometric programming for delay/area minimization is presented. In the first step, Elmore delay is minimized using only minimum and maximum transistor size constraints. In the second step, the minimized delay found in the previous step is used as a constraint for area minimization. In this way, our method can target simultaneously both delay and area reduction. Moreover, by relaxing the minimized delay, one may further reduce area with small delay penalty. Gate sizing may be accomplished through transistor sizing tying each transistor inside a cell to a same scale factor. This reduces the solution space, but also improves runtime as less variables are necessary. To analyze this tradeoff between execution time and solution quality a comparison between gate sizing and transistor sizing is presented. In order to qualify our approach, the ISCAS??85 benchmark circuits are mapped to a 45?nm technology using a typical standard cell library. Gate sizing and transistor sizing are performed considering delay minimization. Gate sizing is able to reduce delay in 21?%, on average, for the same area and power values of the sizing provided by standard-cells library. Then, the transistor sizing is executed and delay can be reduced in 40.4?% and power consumption in 2.9?%, on average, compared to gate sizing. However, the transistor sizing takes about 23 times longer to be computed, on average, using a number of variables twice higher than gate sizing. Gate sizing optimizing area is executed considering a delay constraint. Three delay constraints are considered, the minimum delay given by delay optimization and delay 1 and 5?% higher than minimum delay. An energy/delay gain (EDG) metric is used to quantify the most efficient tradeoff. Considering the minimum delay, area (power) is reduced in 28.2?%, on average. Relaxing delay by just 1?%, area (power) is reduced in 41.7?% and the EDG metric is 41.7. Area can be reduced in 51?%, on average, relaxing delay by 5?% and EDG metric is 10.2.     

Ciprofloxacin increases hepatic and renal lipid hydroperoxides levels in mice

Ciprofloxacin (CFX) is an effective and relatively safe antimicrobial used in a variety of human infections. However, adverse drug reactions and positive results in genotoxic tests are reported.
In order to understand the possible pathophysiological mechanisms of the toxic effects informed for CFX, lipid hydroperoxides (LOOH) -oxidative mediators of peroxidation- were quantified in liver and kidney of mice, after 15 to 360 minutes of the ciprofloxacin administration at doses of 10 mg/ Kg or 100 mg/ Kg by ip route. The peroxidation in the lipid fraction was evaluated by measuring the amount of hydroperoxides through the oxidation of 1- naphthyldiphenylphospine into its oxide and further quantification by high performance liquid chromatography.
The initial content of lipid hydroperoxides (nmol/g tissue) was 253 ± 3 in kidney and 143 ± 12 in liver. CFX induced the maximal variation to 728 ± 101 in kidney (P < 0.05) and 315 ± 31 in liver (P < 0.01), after 15 min of 100 mg/ Kg single dose. The variation in the LOOH levels was significant in kidney with both doses used and in liver after 100 mg/ Kg until 60 min after the CFX administration, and then gradually fell to natural levels.
The results demonstrated the effect of CFX on lipid oxidation, an indicator of oxidative effect. A natural protective capacity against this oxidation, more efficient in liver than in kidney, was observed.     

Microbiological and physicochemical characteristics and aminopeptidase activities during ripening of Serrano cheese

The physicochemical and microbiological characteristics and the aminopeptidase activity variation of Serrano cheese during winter and summer were investigated. Samples from different producers varied significantly, showing nonstandardized procedures for the manufacturing and ripening of this product. There were no significant changes in aminopeptidase activity during maturation and most of the enzyme activity found in the water extracts of cheese would have their origin in lactobacillus and enterococci, suggesting autolysis of these micro-organisms. Results show an increase in free amino acids during maturation, with higher amounts in the summer product.