Psidium cattleyanum Sabine as a Source of Bioactive Compounds for Skin Disorders

<i>Psidium cattleyanum</i> Sabine (strawberry guava, araçá) is an ethnomedicinal plant with reputed health benefits; however, its potential for treating skin disorders remains underexplored. This study aimed to characterize the phytochemical profile of <i>P. cattleyanum</i> leaves from Cabo Verde and evaluate their bioactivity relevant to skin health. Phytochemical analysis was performed using high-performance liquid chromatography-mass spectrometry (LC-MS) and spectrophotometric assays. Key biological activities were assessed in vitro, including antioxidant capacity (free radical scavenging assays), anti-aging enzyme inhibition (collagenase, elastase, and tyrosinase), and antibacterial activity against skin pathogens (agar diffusion, minimum inhibitory concentration, and combination studies with standard antibiotics). Cytotoxicity was evaluated using Vero cells (MTT assay). Additionally, a topical cream containing the leaf extract was formulated and subjected to physicochemical stability and sensory testing. LC-MS revealed a rich polyphenolic composition in the leaf extract, including abundant phenolic acids (gallic and ellagic acid derivatives) and flavonoid glycosides. The extract exhibited a high total phenolic content and strong antioxidant activity in DPPH/ABTS assays. It showed potent inhibition of collagenase, elastase, and tyrosinase, indicating an anti-aging effect against wrinkle formation and hyperpigmentation. The extract also demonstrated broad antimicrobial efficacy against skin-associated bacteria, such as <i>Staphylococcus aureus</i> and <i>Cutibacterium acnes</i>, with no antagonism and partial synergism observed when combined with certain antibiotics. The <i>P. cattleyanum</i> extract was successfully incorporated into a cream formulation that remained physically and chemically stable (no phase separation, consistent droplet size, and pH) over 90 days, with good homogeneity and acceptable sensory characteristics (neutral odor, smooth texture, and good spreadability). <i>P. cattleyanum</i> leaves from Cabo Verde are a rich source of bioactive compounds with multifunctional dermatological benefits. This study demonstrates that the <i>P. cattleyanum</i> leaf extract exhibits significant antioxidant, antimicrobial, and anti-aging activities in vitro, supporting its potential use as a natural ingredient for skin care.