Uv vis spectrophotometer 2401pc

MHM3 isolate was grown in liquid medium containing (g/L) sucrose 50; peptone 4 and yeast extract 2; and dissolved in 750 ml seawater at pH 7 (Jing et al., 2013). The fermentation cultures were then incubated at 37°C with shaking at 100 rpm for 3 days. The fermented broth was collected and centrifuged at 4,000 rpm at 4°C for 30 min to remove bacteria cells. Trichloroacetic acid TCA 5% was added and left over night at 4°C and centrifuged at 5,000 rpm to remove protein. The pH of the clear solution was adjusted to 7.0 with NaOH solution (Liu et al., 2011). Four volumes of cold absolute ethanol was added to the supernatant and the precipitate was collected by centrifuged. The precipitate obtained was re-dissolved in deionized water followed by dialysis against deionized water for 48 h. The dialyzed solution was subjected to fractional precipitated by 1, 2, 3, and 4 volumes of cold absolute ethanol. The yield major fraction obtained by two volumes of absolute ethanol was lyophilized and coded MHMEPS. The UV absorption spectrum was recorded using a UV-Vis Spectrophotometer 2401PC (Shimadzu, Japan) between 200 and 800 nm, in order to examine the existence of proteins and nucleic acids (Wang and Luo, 2007). The yield of MHMEPS was determined by Dubois method.