Comparative Effects of Garcinia kola and Coffee Diets on Learning and Memory in Mice

Background: Garcinia kola (bitter kola) is one of the most common masticatories in Nigeria having social and ethnomedicinal applications. G. kola seeds are believed to contain caffeine, one of the major constituent of coffee which is also believed to improve memory.
Aim: This study was set to ascertain the caffeine content of G. kola and compare the effects of G. kola and coffee diets on learning and memory in mice.
Methodology: Thirty male CD1 mice were randomly assigned into three groups, viz; control, Garcinia koladiet (30%w/w) and coffee diet (2%w/w) groups. Chemical content and LD50 of the Garcinia kola and coffee were determined using standard methods. Daily food intake, water intake and body weight changes were also measured for 31 days before testing for learning and memory. The Morris water maze was used to assess learning and memory.
Results: The major constituents of Garcinia kola were alkaloids (high quantities), saponins, tannins, flavonoids, glycosides, sterols and phenols found in moderate quantities. The coffee contained high quantity caffeine (4.7%) whereas alkaloids, saponins, tannins, flavonoids, and phenols were present in slight quantities. Coffee diet decreased food intake, water intake body weight change in the mice when compared to G. kola and control diet groups (p<0.05). On the other hand, coffee diet fed mice showed better learning and memory when compared to G. kola diet-fed and control mice. Garcinia kola diet did not affect learning and memory.
Conclusion: Coffee diet decreased food and water intake and body weight, but improved learning and memory in mice when compared to Garcinia kola.