Organic Suitable for Vegetarians Rich in Vitamin C Spirulina is well known for being a rich source of nutrients and providing the highest plant based source of protein known to man.Bioglan Superfoods Organic Spirulina Capsules are rich in Vitamin C which contributes to the protection of cells from oxidative stress and the normal function of the immune system. Vitamin C also contributes to the reduction of tiredness and fatigue.