**10.** *Picrorhiza kurroa* **Royle ex Benth**

*Picrorhiza kurroa*, an ayurvedic herb, has been shown to potentiate photochemotherapy in vitiligo [74]. Apocynin **(30)** from *P. kurroa* has shown to be neuroprotective *in vivo* [75]. It also shows protective effect in a mouse model of chemically induced colitis [76]. It (4-hydroxy-3-methoxy-acetophenone, **30**) mediates long-lasting memory recovery, helps in hippocampal neuroprotection, and reduces glial cell activation after transient global cerebral ischemia in rats [77]. Interestingly, the concentration of picrosides I **(31)** and II **(32)** and apocynin **30** (iridoid rich fraction) in plasma (*C*max) was found to be 244.9, 104.6, and 502 ng/ml with half-life (*t*1/2) 14, 8, and 6 h, respectively [78]. *P. kurroa* also prevents memory deficits by inhibiting NLRP3 Inflammasome Activation and BACE1 Expression in 5xFAD Mice [79]. Acylated iridoid glycosides with hyaluronidase inhibitory activity from the rhizomes of *P. kurroa* Royle ex Benth have recently been isolated [80]. Therapeutic potentials of plant iridoids in Alzheimer's and Parkinson's diseases have separately been reviewed recently [81].
