Density of HIV-1 is not altered by aqueous P. vulgaris extract. HIV NL4-3 virions were untreated or treated with 0.5% Triton X-100, 132 μg/mL of aqueous extracts of Ames 27664 or 126 μg/mL of Ames 27748 for 1 hour at 37°C. Virus was applied to the top of a 20-60% sucrose gradient and ultracentrifuged. Fractions were collected, separated on SDS PAGE and transferred to nitrocellulose. The blot was probed with an antibody against HIV-1 p24.