I suppose that is 'Basella alba' (in a FAO book about Africa, they used 'Ceylon Spinach' https://books.google.fr/books?id=6jrlyOPfr24C&pg=PA104&dq=Basella+alba&hl=fr&sa=X&ved=0ahUKEwiqrZD_loLgAhVp2OAKHW9IBREQ6AEIUTAG#v=onepage&q=Basella%20alba&f=false
Dear colleague, you can find a complete nutritional analysis of Basella alba in Tindall, H. D., Vegetable in the tropics, MacMillan - various editions, no doubt you can easily find one online.