“Have you ever seen a Geami roll?” asks Gillian Reynolds, as she pulls out a box of what looks like ripped paper. Reynolds owns 2-year-old Jamnation, a jam company in San Francisco’s Bayview neighborhood. The Geami roll is biodegradable packing material that she uses instead of bubble wrap to protect her jars during shipping. It’s one of several eco-friendly touches that reflects a commitment to sustainability — and distinguishes her company from similar ones. In…