Honey, pollen, and propolis ("bee glue" resin from trees) appear to be MAO inhibitors in the test tube.
Especially propolis. The active ingredient in it appears to be APIGENIN, which is available as a supplement. It protects against a-syn aggregation, ROS, increases BDNF, is an MAO inhibitor, and increases dopamine uptake.
But like Xanthumol (which may work by increasing activity of GM1 like nilotinib that affect Bcr/Acl inhibitor) it also stops excess glutamate which is key in many neurodegeneration like that caused by hypoxia.
Luteolin and apigenin are the main active ingredients in Chamomile (tea) and artichoke which can be bought as extracts. Their molecular weights are less than 400 (270) so they might cross blood brain barrier, although luteolin was found to not be bioavailable in one study, although its metabolites might be the active ingredients. 200 mg for either is the dose needed to copy the work in mice, but that is a bit high.
Apigenin is about 0.005% in orange juice, which is a decent amount. Hesperidin is 10x higher. Naringin in grapefruit juice is also 10x higher. 400 g grapefruit juice contains 0.2 g naringin.
Parsley and celery have the highest amounts, about 2% in fresh wet parsley, but maybe only 1% seems to reach blood stream. So 10 grams of parsley should give 200 mg Apigenin.
luteolin and apigenin "enhancing monoamine uptake" "monoamine transporter activators"
apigenin is an inhibitor of liver enzyme CYP2C9 so the list in the link below needs to be consulted if you're taking medication. It will amplify the effect of any drugs listed in the "substrate" column by not letting them be broken down. Most notably NSAIDs.
"In conclusion, apigenin and luteolin protected the dopaminergic neurons probably by reducing oxidative damage, neuroinflammation and microglial activation along with enhanced neurotrophic potential. The above results propose both these flavonoids as promising molecules in the therapeutics of PD. "
apigenin promotes neurogenesis
Bee products are MAO inhibitors, propolis is stronger.
Apigenin is main active ingredient in propolis, targets the preferred MAO-B (less chees effect) strongest
"has been used as a sedative and tranquilizer in Brazilian folk medicine and as a natural anxiolytic agent. Flavonoids from Passiflora edulis and P. alata have been shown to improve behavioral performance in rats . The phytochemicals that contribute most to the effects of Passiflora are flavonoids such as apigenin-8-C-β-digitoxopyranoside, apigenin-8-C-β-boivinopyranoside (Figure 6), and luteolin-8-C-β-boivinopyranoside . Apigenin and its derivatives are known to have anticarcinogenic, antioxidant, and anti-inflammatory properties . Subchronic treatment with apigenin in APP/PS1 mice model downregulates BACE, β-CTF, and β-amyloid deposition and restores BDNF expression leading to increased memory and synaptic plasticity by ERK1/2/CREB-mediated prevention of AD . Recently, we studied apigenin and found that it also plays a vital role in neurodegenerative disease. It exerts its anti-inflammatory effect on LPS-activated microglia and inhibits NO and PGE2 production by scavenging free radicals. Moreover, apigenin suppresses ERK1/2, p38 MAPK, and JNK and modulates NGF-induced neurite outgrowth in PC12 cells . Additionally, apigenin has an apparent permeability coefficient in the BBB, and thus it serves as an effective phytochemical for the treatment of neurodegenerative diseases "