Hebei Huari Pharmaceuticals Co., Ltd.
Mainly produces and distributes the bulk penicillin G procaine and its relevant products.
http://www.huari-pharm.com/

Penicillium chrysogenum
Article by Tom Volk on this useful fungus, the source of penicillin, and its discovery by Alexander Fleming.
http://botit.botany.wisc.edu/toms_fungi/nov2003.html

Fersinsa Gb
Dutch-Mexican company producer of penicillin and its semi-synthetics derivates: ampicillin, amoxicillin and dicloxacillin. Company and product information.
http://www.fersinsa.com

Alembic Ltd.
ISO 9002 and 14002 certified company that specializes in penicillin bulk and macrolides antibiotics (so called erythromycins and derivatives). Site features company news and information to several human and animal healthcare products.
http://alembic-india.com/