Grapefruit contains quinine-like substances, which in turn are effective in treating malaria. To make the most of it, heat up 1 grapefruit and eat its pulp. Indulge in fresh grapefruit and orange juice daily. Make it even more powerful by adding fresh ginger to the mix and turmeric powder. This grapefruit juice is not only a great barrier against viruses but an immune system booster against any disease. Have plenty of grapefruits and fresh grapefruit juice on a daily basis.
From Google search on natural sources of quinine.
Thanks, I’ll look into it.