Jk. Uyemoto et al., AN IMPROVED PURIFICATION PROCEDURE FOR GRAPEVINE LEAFROLL ASSOCIATED VIRUSES, American journal of enology and viticulture, 48(4), 1997, pp. 521-524
Higher yields of purified grapevine leafroll associated viruses (GLRaV
) types 1 and 2 were consistently realized when an acidic extraction b
uffer [0.5 M potassium phosphate, pH 6.4; 4% polyvinyl polypyrrolidone
(PVPP), without bentonite] was used. In contrast, yield of purified v
iruses was problematical using 0.5 M Tris-HCl buffer, pH 8.2, PVPP, ei
ther with or without bentonite. Relative virus yields were determined
by ELISA. The consistency in virus yields was probably due to increase
d activity of the polyphenol absorbent, PVPP, when it was suspended in
a slightly acidic solution. For GLRaV-3, yields of purified virus wer
e somewhat comparable irrespective of extraction buffer or bentonite.