Please make sure that the Bill of Lading should be ONE, otherwise you will pay much there in UK customs house.
But here in China, it is difficult to issue one B/L with several supplier because each supplier should make customs clearance seperately.
My advice is that you ask the big supplier(the volume is the biggest) to collect all products from other supplier and then ask this supplier to handle delivery to the loading port and the forwarder issue ONE B/L.
Otherwise you will pay a very little money to the shipping forwarder and ask them to issue just ONE B/L