Local Wisdom and Diversity of Medicinal Plants in Cha Miang Forest in Mae Kampong Village, Chiang Mai, Thailand, and Their Potential for Use as Osteoprotective Products

“People-Forest-Miang” communities are villages located in the cultivated area of Camellia sinensis var. assamica, or Cha Miang, in northern Thailand. Cha Miang forests are a form of agriculture relying on forest-rich bioresources. This study focuses on a survey of the diversity of medicinal plants used by “People-Forest-Miang” communities in Mae Kampong Village, Chiang Mai, Thailand. The results demonstrated that 73 species of medicinal plants were used to prevent and treat various ailments. The highest number of species (30.14%) was used for musculoskeletal system disorders, followed by digestive system disorders (21.92%) and unspecified medicinal disorders (15.07%). The alkaline phosphatase (ALP) is the most widely recognized biochemical marker for osteoblast activity. The ALP activity of ethanol and deionized water extracts of the nine selected medicinal plants used for musculoskeletal system disorders were examined in the MG63 cell line. The results showed that the numerous water extracts, including MKP1, MKP2, MKP5, MKP6, MKP7, MKP8, and MKP9, and the ethanolic extracts—namely, MKP2, MKP3, MKP7, and MKP9—significantly increased ALP activity in the MG-63 cell line. The findings indicate that some medicinal plants may be further studied for active chemicals and developed as natural active pharmaceutical ingredients for osteoprotective products.