I would use a comma here because that is the way I say it in speaking and because the comma helps me read it correctly by helping me to identify the numeric expression as part of the subject. Without the comma, I (temporarily) imagine the numeric expression to be somehow part of the prepositional phrase, read quickly, as in:
In all variants 0.1% or more in water content, ...
In all variants (that are) 0.1% water in content, ...
In all variants (that) 0.1% water suspensions of these strains allow, ...
In all variants (that) 0.1% water suspensions of these strains were used in, ...
By the time I reach the period (full stop), this misreading no longer applies, but I would prefer not to be misled in the first place.
