Biosynthesis of bakuchiol from cinnamic and p-coumaric acids

Specific incorporation of l-[U-¹⁴C]phenylalanine, [U-¹⁴C]cinnamic acid and p[2-¹⁴C]coumaric acid into bakuchiol has been observed in Psoralea corylifolia. Our findings show that the aromatic moiety along with two carbon atoms of the side chain are biosynthetically derived via phenylpropane pathway and not by the alternate pathway proposed earlier.     

Bakuchiol inhibits lung cancer by modulating tumor microenvironment and the expression of PD-L1

Immune checkpoint therapy is an emerging frontier in cancer therapy. With the aim to develop an efficient herb derived compound to facilitate immune checkpoint therapy, here we investigate if a herb-derived compound, Bakuchiol (BAK), can be used to treat lung cancer and elucidate if BAK could serve as a PD-L1 regulator. To this end, a murine lung cancer model was established by subcutaneously inoculating murine Lewis lung carcinoma (LLC) cells. BAK of 5 to 40 mg/kg was used for treatment in vivo for 15 days. On Day 15, the population of CD4+ and CD8+ T cells, Treg cells. BAK could effectively inhibit tumor growth by starting treatment either on Day 0 or 6 after tumor inoculation at doses of 5−40 mg/kg. BAK treatment increased the population of cytotoxic immune cells (i.e., CD8+ T cells, and M1 macrophages), meanwhile decreasing pro-tumor immune cells (i.e., CD3+ T cells, Treg cells, and M2 macrophages). Anti-inflammatory cytokines, including IL1β, IL2, IFNγ, TNF-α, IL4 and IL10 were upregulated by BAK. PD-L1 expression in the tumor was also lowered by BAK. AKT and STAT3 signaling were inhibited by BAK. BAK is an efficient agent in reducing LLC tumor growth. These data support the potential of BAK as a new drug for treating lung cancer by serving as a PD-L1 inhibitor that suppresses the activation of AKT and STAT3.     

Biosynthesis of bakuchiol,a meroterpene from Psoralea corylifolia

Biosynthesis of bakuchiol was examined using phenylalanine and mevalonic acid as substrates. It has been demonstrated that bakuchiol is derived from one phenylpropane (with the loss of one carbon atom) and two isoprenoid (C₅) units.     

Isobavachalcone and bavachinin from Psoraleae Fructus modulate Aβ42 aggregation process through different mechanisms in vitro

Spontaneous aggregation of Aβ is a key factor in the development of Alzheimer’s disease. In searching for Aβ aggregation inhibitors from traditional Chinese herbal medicines, we identified two active compounds from Psoraleae Fructus, namely isobavachalcone and bavachinin. We further demonstrated that the two compounds modulate Aβ42 aggregation process through different mechanisms. Isobavachalcone significantly inhibits both oligomerization and fibrillization of Aβ42, whereas bavachinin inhibits fibrillization and leads to off-pathway aggregation. Both of the compounds attenuated Aβ42-induced toxicity in a SH-SY5Y cell model. These findings may provide valuable information for new drug development and Alzheimer’s therapy in the future.     

Enrichment of bakuchiol in supercritical carbon dioxide extracts of chiba seed (Psoralea corylifolia L.) using molecular distillation-Response surface methodology

Chiba seed (Psoralea corylifolia L.) oil, which contains bioactive components such as bakuchiol, psoralen, and isosporalen, is recognized for its high medicinal value and is widely used in Chinese and Indian Ayurvedic medicinal systems. Several earlier studies have proved the antibacterial and antioxidant properties of the key components in the seed oil. In view of the importance of the bioactive components in the global market, this study was carried out to separate the key components by supercritical carbon dioxide extraction and further enrichment by the molecular distillation technique. The effects of the process variables such as pressure (400∼2,000 μm), temperature (140∼200°C), and wiper speed (120∼200 rpm) were studied based on response surface methodology. The predicted model was maximized for the bakuchiol content in the distillate. And a predicted maximum of 72% bakuchiol content was confirmed by the experiment under the optimized process conditions.     

Inhibitory Effects of Bakuchiol,Bavachin, and Isobavachalcone Isolated from Piper longum on Melanin Production in B16 Mouse Melanoma Cells

An EtOH extract of fruits of Piper longum was found to exhibit a potent inhibitory effect against α-melanocyte-stimulating hormone (α-MSH)-induced melanin production in B16 mouse melanoma cells. Bioassay-directed fractionation led to the isolation of prenylated phenolic compounds bakuchiol, bavachin, and isobavachalcone. These compounds and the crude extract of the fruits of P. longum may have suppressive effects against pigmentation by melanin in the skin.