Drug susceptibility of Spanish Mycobacterium tuberculosis complex isolates from animals.

Mycobacterium bovis and Mycobacterium caprae are zoonotic bacteria that cause tuberculosis with several clinical manifestations. We have evaluated the susceptibility to anti-tuberculosis drugs of a panel of Spanish isolates of animal origin. The analysis of the sequence of the main genes involved in resistance was performed in 41 M. bovis and five M. caprae. The katG, inhA, rpsL, embB and gyrA genes had single nucleotide polymorphisms, not previously described in other organisms of the complex. Thirty-two M. bovis and three M. caprae isolates were tested for susceptibility to isoniazid (INH), rifampin, streptomycin, ethambutol, and ofloxacin using the standard proportion method. The results revealed that the isolates were sensitive to the five drugs. However, interference caused by sodium pyruvate in the INH test was detected: 94.3% grew at 0.2 microg INH/ml and 68.6% grew at 1 microg INH/ml. In the medium without pyruvate, 34.3% of the isolates did not grow whereas growth of the others was poor and slow. Nine M. bovis isolates were also tested by ESP Culture System II test and were sensitive to INH. The susceptibility of M. bovis to INH cannot be reliably determined using the standard proportion method due to the M. bovis growth requirements and the interference of pyruvate with INH.

Microwave-assisted enhancement of milkweed (Calotropis procera L.) leaves as an eco-friendly source of natural colorants for textile.

Application of natural colorants to textile fabrics has gained worldwide public acceptance due to the hazardous nature of synthetic dyes. Present study investigated the microwave's mediated extraction of natural colorants from leaves of milkweed (Calotropis procera L.) as well as their application to cotton fabrics assisted with biochemical mordants. Dye extraction from C. procera leaves was carried out in various mediums (alkali and aqueous), and the extracted dye as well as cotton fabrics was irradiated with microwaves for 2, 4, 6, 8, or 10 min. Effect of various temperature regimes and sodium chloride (NaCl) concentrations was also evaluated on the color strength of dyed cotton fabrics. The results revealed that extraction of natural colorants was enhanced when microwave radiations were applied for 4 min by using alkali as an extraction medium as compared to aqueous one. Optimum dyeing of cotton fabrics was achieved by using NaCl at a temperature of 55 °C. Among the chemical mordants, iron was effective for better color strength when used as pre- and post-mordant. Among the studied bio-mordants, extract of Acacia nilotica bark significantly improved the color strength and fastness properties as pre-mordant and Curcuma longa tuber as post-mordant. It was concluded that extract of C. procera leaves was a potential source of natural colorants and a high level of dye was obtained upon irradiation of alkali-solubilized extract for 4 min. Application of NaCl at concentration of 3 g/100 mL and temperature treatment of 55 °C significantly improved the color strength of dyed cotton fabrics.

Cellular proton dynamics in Elodea canadensis leaves induced by cadmium.

Our earlier investigations showed that Elodea canadensis shoots, grown in the presence of cadmium (Cd), caused basification of the surrounding medium. The present study was aimed to examine the proton dynamics of the apoplastic, cytosolic and vacuolar regions of E. canadensis leaves upon Cd exposure and to establish possible linkage between cellular pH changes and the medium basification. The changes in cytosolic calcium [Ca(2+)]cyt was also investigated as the [Ca(2+)]cyt and [pH]cyt homeostasis are closely linked. The cellular H(+) and Ca(2+) concentrations were monitored by fluorescence microscopy and ion-specific fluorescent dyes. Cadmium concentration of leaf-cell walls was measured after plant cultivation at different fixed levels of starting pH. The protoplasts from E. canadensis leaves were isolated by use of a newly developed enzymatic method. Upon Cd addition, both cytosolic and vacuolar pH of leaf protoplasts increased with a concomitant rise in the cytosolic Ca(2+) concentration. Time course studies revealed that changes in [Ca(2+)]cyt and [pH]cyt followed similar dynamics. Cadmium (0.5 µM) exposure decreased the apoplastic pH by 0.85 units. The maximum cell wall bound Cd-contents were obtained in plants grown at low starting pH. It is concluded that Cd treatment causes apoplastic acidosis in E. canadensis leaves associated with enhanced Cd binding to the cell walls and, consequently, reduced Cd influx into the cytosol.