References:
Nakata A, Yamashita SI, Suzuki N, Liang TF, Kuniyoshi T, Yang JW & Takara T. 2018. Effect of an Apocynum Venetum leaf extract (Venetron) on sleep quality and psychological stress improvement. Jpn Pharmacol Ther.46(1): 117-125.
Yamatsu A, Yamashita Y, Maru I, Yang JW, Tatsuzaki J & Kim M. 2015. The improvement of sleep by oral intake of GABA and Apocynum Venetum leaf extract. Journal of Nutritional Science and Vitaminology. 61: 182-187.
Chiu S, Gericke N, Woodbury MF, Badmaev V, Raheb H, Terpstra K, Antongiorgi J, Bureau Y, Cernovsky Z, Hou JR, Sanchez V, Williams M, Copen J, Husni M & Goble Liz. 2014. Proof-of-concept randomized controlled study of cognition effects of the proprietary extract Sceletium tortuosum (Zembrin) targeting phosphodiesterase-4 in cognitively healthy subjects: Implications for Alzheimer's dementia. Evidence-Based Complementary and Alternative Medicine. Article ID 682014.
Dimpfel W, Gericke N, Suliman S & Dipah GNC. 2016. Psychophysiological effects of Zembrin® using quantitative EEG source density in combination with eye-tracking in 60 healthy subjects. A double-blind, randomized, placebo controlled, 3-armed study with parallel design. Neuroscience and Medicine. 7: 114-132.
Terburg D, Syal S, Rosenberger LA, Heany S, Phillips N, Gericke N, Stein DJ & Honk JV. 2013. Acute effect of Sceletium tortuosum (Zembrin), a dual 5-HT reuptake and PDE4 inhibitor, in the human amygdala and its connection to the hypothalamus. Neuropsychopharmacology. 1-9.
Alsmadi AM, Tawalbeh LI, Gammoh OS, Shawagfeh MQ, Zalloum W, Ashour A & Attarian H. 2017. The effect of Ginkgo biloba and psycho-education on stress, anxiety and fatigue among refugees. Proceedings of Singapore Healthcare. 27(1): 26-32.
Kennedy DO. 2016. B vitamins and the brain: Mechanisms, dose and efficacy – A review. Nutrients. 8(68).
Mikkelsen K, Hallam K, Stojanovska L & Apostolopoulos V. 2018. Yeast based spreads improve anxiety and stress. Journal of Functional Foods. 40: 471-476.