Chemical, pharmacological properties and biosynthesis of opioid mitragynine in Mitragyna speciosa (kratom)

In vivo analgesic, anti-inflammatory activities, and phytochemical profile of Thai herbal Kratom recipe, a traditional Thai herbal medicine for muscle pain relief

ETHNOPHARMACOLOGICAL RELEVANCE

Thai herbal Kratom (THK), a traditional Thai remedy for muscle pain, is composed of six important medicinal plants and has been traditionally used as a compressed ball for muscle pain management. This study aimed to evaluate its phytochemical composition and biological properties, including antioxidant, anti-inflammatory, and analgesic actions.

MATERIALS AND METHODS

The phytochemical profile was investigated, and antioxidant activity was assessed using DPPH and ABTS scavenging assays. In vivo anti-inflammatory properties were examined using carrageenan-induced rat paw edema and ethyl phenylpropiolate (EPP)-induced ear edema, while anti-nociceptive activity was explored by the hot plate test and acetic acid-induced writhing test.

RESULTS

The ethanolic extract of THK was found to contain several potent phytochemicals, including 4-hydroxycoumarin, curcumin, mitragynine, aloin A, and limonin. HPLC analysis revealed a high concentration of mitragynine in the extract, with a value of 10.76 ± 0.50 mg/L. The extract demonstrated an antioxidant activity in DPPH and ABTS scavenging assays, with IC50 value of 275.15 ± 1.78 and 256.49 ± 6.66 μg/mL, respectively. Oral administration of THK at dose of 125-500 mg/kg exhibited promising anti-inflammatory activity in a dose-dependent manner by reducing carrageenan-induced rat paw edema. Topical application of THK (1-2 mg/ear) was shown to highly inhibit ear swelling at 120 min after EEP-induced inflammation, with values of 83%, which was more potent activity than indomethacin treatment at 30, 60, and 120 min. Furthermore, THK at 125 mg/kg significantly reduced pain response in both the hot plate and acetic acid-induced writhing tests.

CONCLUSION

This study found that the ethanolic extract of THK possesses significant anti-inflammatory and analgesic activities in vivo, supporting its traditional use for muscle pain management.

Post-genomic illumination of paclitaxel biosynthesis

Paclitaxel rapidly became one of the most effective anticancer drugs. However, the production of paclitaxel is hindered by substantial challenges, particularly considering the significant quantities of drug required and the inherently low concentration of paclitaxel and its intermediates in plants. Paclitaxel is currently produced in a so-called semi-synthesis in which baccatin III is extracted from Taxus species and chemically converted to paclitaxel. Despite the fact that many of the intermediates of paclitaxel biosynthesis are yet to be experimentally determined, a set of recent papers-facilitated by the sequencing and assembly of three Taxus genomes-has uncovered the minimal gene sets for both baccatin III and paclitaxel biosynthesis. Here we summarize the key milestones towards our understanding of paclitaxel biosynthesis and highlight recent advancements made possible by genome-level analysis of potential key genes involved. We argue that these studies will ultimately pave the way towards the elucidation of the entire paclitaxel biosynthetic pathway and facilitate the industrial production of paclitaxel via synthetic biology approaches. However, several major challenges lie ahead before we can fully tap into the amazing curative potential that taxanes provide.