Does the juice of the passiflora vine contain sulfur?

This might sound like a strange question, but I think my Lacandon guide used it to make rubber. He mixed the juice of some vine with dark green, leaves that look like those of a passiflora with the latex of the Castilla elastica. Does this sound right? I'm not a passiflora expert; I know that the Mayas use the juice from the morning glory to make rubber, but passiflora? I don't have a photo of the vine, only a video.

For lack of reponses, I take it that no one knows anything about this. I'm closing the thread, to reduce the clutter.