Qualitative Phytochemical Screening of Medicinal Plants Used by Partido Albularyo in Camarines Sur, Philippines

Ethnobotanical use value can guide the selection of medicinal plants for laboratory phytochemical documentation. This study characterized the qualitative phytochemical profiles of 33 medicinal plants selected from an ethnobotanical dataset in Camarines Sur, Philippines. Plant materials were extracted by 72-h cold maceration in ethanol (1:10, w/v), and extracts were screened for alkaloids, flavonoids, glycosides, phenolics, phytosterols, phlobatannins, steroids, terpenoids, and saponins using established pharmacognostic reactions. Reaction intensities were recorded as absent, trace, moderate, or abundant. Prevalence was summarized with 95% Wilson confidence intervals; phytochemical richness and an ordinal screening index were calculated; Cochran’s Q and Friedman tests characterized overall variation across assay classes; and Spearman correlation related published use value to screening metrics. Alkaloids, flavonoids, phenolics, and saponins were detected in all 33 taxa. Phytosterols occurred in 93.9%, phlobatannins in 84.8%, steroids in 48.5%, terpenoids in 27.3%, and glycosides in 18.2%. Overall distributional tests were significant (Cochran Q = 151.59, df = 8, p < 0.001; Friedman χ²(8) = 184.02, p < 0.001; Kendall W = 0.70). Mean phytochemical richness was 6.73 ± 0.98 classes per taxon, and the mean screening index was 12.52 ± 2.71. Coleus amboinicus reacted positively for all nine classes and, together with Moringa oleifera, attained the highest screening index (18/27). Published use value was positively associated with richness (Spearman ρ = 0.54, p = 0.0010) and the screening index (ρ = 0.61, p < 0.001). The findings provide a structured qualitative chemical-class profile of ethnobotanically important medicinal plants used in Partido District.