Narrative synthesis of the medicinal plants in Luzon, Philippines based on online publications from 1996 to 2020

• Main Authors: Constantino, Koleen Faye Umali, Salazar, Mark Joseph Condeno
• Format: text
• Language: English
• Published: Animo Repository 2022
• Subjects: Medicinal plants > Philippines > Luzon; Electronic publications; Biology; Plants
• Online Access: https://animorepository.dlsu.edu.ph/etdb_bio/13; https://animorepository.dlsu.edu.ph/cgi/viewcontent.cgi?article=1016&context=etdb_bio
• Institution: De La Salle University

In the Philippines, there is currently an aggressive interest in pursuing studies on medicinal plants in an attempt to discover novel cost-effective and safe cure for human diseases. The main objective of this paper is to come up with a narrative synthesis on the medicinal plants found in Luzon covering a 25-year period (1996-2020). A total of 138 articles published online was used in this study. Data gathered from each article were encoded in a spreadsheet under 5 categories: Journal information, plant demographics, methodology, secondary metabolites, and plant bioactivity. Results showed that of the 138 published papers, 9 were ethnobotanical and 129 were experimental studies. A total of 672 plant species were documented, 464 plants species were from ethnobotanical data and 208 plant species were from experimental data. Most published articles were authored by researchers from NCR, Bicol region, and Central Luzon. Most number of plant species reported were from the CAR. The highest number of medicinal plants reported belong to the family Asteraceae. All experimental publications (n=129) included methods on extract preparation, phytochemical screening, pure compounds identification, and biological activity screening. The plant extracts were mostly prepared from the leaves. The most abundant secondary metabolites obtained were terpenoids, sterols, and flavonoids. The most number of biological activities were exhibited by families Fabaceae and Myrtaceae. Biological activities mostly reported are antimicrobial, anti-cancer, anti-inflammatory, and anti-diabetes. These biological activities were attributed to the presence of secondary metabolites such as alkaloids, terpenoids, sterols, and flavonoids. One hundred twelve plant species were tested for potential cytotoxic activity while 23 were assayed for their genotoxicity. Six secondary metabolites (sterols, flavonoids, tannins, terpenoids, glycosides, and alkaloids) commonly found in medicinal plants exhibited antimicrobial, anti-inflammatory, anti-diabetes, anti-cancer, and heart disease treatment properties. It is recommended that the future narrative synthesis should include published experimental works that are not available online as well as unpublished works from different academic institutions.