One gram of sample was homogenized in 3 mL metaphosphoric
acid at 3 % v/v for 3 min, the mixture was filtered and 1 mL supernatant was diluted to 10 mL with metaphosphoric
acid at 3 % v/v.
Approximately 5 mL of the strained rumen fluid was taken for microbial population study while another 10 mL of the fluid was mixed with 2 mL 25% metaphosphoric
acid (w:v) for volatile fatty acid analysis.
In addition, 400 [micro]L of the supernatant from the other microcentrifuge tube was mixed with 400 [micro]L of a metaphosphoric
acid solution (Sigma Aldrich, St Louis, MO, USA) for deproteination.
A 10 ml of ruminal fluid was acidified with 1 ml H2SO4 (50%) for ruminal NH3-N analysis and 10 ml of ruminal fluid was mixed with 2 ml of 25% (wt/vol) metaphosphoric
acid for volatile fatty acid (VFA) analysis.
A comparison of metaphosphoric
and oxalic acids as extractant solutions for the determination of vitamin C in selected vegetables.
One hundred-microliter aliquots of washed RBCs were added to 300 mL ice-cold 5% metaphosphoric
At the end of each incubation period 5 ml of culture medium were obtained and centrifuged at 18000 G for 10 min; 2.0 ml of the supernatant was mixed 4:1 with 25% metaphosphoric
acid, the vials were shaken in a Vortex and re-centrifuged at 35000 G for two minutes, the concentration of VFA was measured using a Claurus 500 gas chromatograph, using the technique and conditions described by Ley de Coss et al (16).
Briefly, 20 mL of metaphosphoric
acid at 4.5% (w/v) was added to 500 mg of the sample and the mixture was stirred with magnetic shaking (P-Selecta, Asincro, Spain) for 15 min under dark conditions.
5 mL of 5% (w/v) metaphosphoric
acid in 20% (v/v) methanol was added into the samples, and the mixtures were sonicated in an ultrasonic bath at room temperature for 10 min.
Renal tissue homogenate was processed by the addition of four volumes of ice-cold 5% metaphosphoric
acid and centrifuged at 4000 rpm for 10 min at 4[degrees]C.
Twenty grams of sample was blended in 30 mL of 3% metaphosphoric
acid solution and homogenized (AM-8, Nihonseike Kaisha, Tokyo, Japan).
Hydrochloric acid, metaphosphoric
acid, formic acid, acetic acid, methanol, acetonitrile, sodium metabisulphite, potassium chloride, sodium acetate, acid potassium dichromate, ethyl acetate, and potassium dihydrogen phosphate were purchased from Merck (Madrid, Spain).