<![CDATA[ABSTRAKPendahuluan: Kandidiasis oral akibat Candida albicans merupakan masalah umum di bidang kedokteran gigi. Kulit buah naga merah (Hylocereus polyrhizus) diketahui mengandung senyawa bioaktif seperti flavonoid dan fenolik yang berpotensi sebagai antijamur. Penelitian ini bertujuan untuk mengetahui efektivitas ekstrak kulit buah naga merah terhadap Candida albicans ATCC 10231 secara in vitro. Metode: Studi eksperimental ini menggunakan metode difusi sumur (well diffusion). Ekstrak diuji dalam dua volume (20 µL dan 100 µL) dan lima konsentrasi (50%, 25%, 12,5%, 6,25%, 3,125%). Nystatin 100.000 IU/mL digunakan sebagai kontrol positif, dan DMSO 2,5% sebagai kontrol negatif. Identifikasi mikroorganisme dilakukan melalui CHROMagar dan pewarnaan hematoksilin eosin. Hasil: Tidak menunjukan zona hambat pada seluruh perlakuan ekstrak. Sebaliknya, Nystatin menunjukkan zona hambat rerata di atas 17 mm, sementara DMSO tidak menunjukkan efek hambatan. Identifikasi morfologi mengkonfirmasi mikroorganisme uji sebagai Candida albicans. Simpulan: Ekstrak kulit buah naga merah tidak menunjukkan aktivitas antijamur terhadap Candida albicans dalam metode difusi sumur (well diffusion). Penelitian lanjutan diperlukan dengan pendekatan dan metode yang berbeda.KATA KUNCI: Candida albicans, buah naga merah, antijamur, flavonoid, difusi sumur.Antifungal effectiveness of red dragon fruit peel extract (Hylocereus polyrhizus) against candida albicans ATCC 10231: study experimentalABSTRACTIntroduction: Oral candidiasis caused by Candida albicans is a common issue in dental medicine. Red dragon fruit peel (Hylocereus polyrhizus) is known to contain bioactive compounds such as flavonoids and phenolics, which have potential antifungal properties. This study aimed to evaluate the antifungal effectiveness of red dragon fruit peel extract against Candida albicans ATCC 10231 in vitro. Methods: This experimental study employed the well diffusion method. The extract was tested in two volumes (20 µL and 100 µL) and five concentrations (50%, 25%, 12,5%, 6,25%, 3,125%). Nystatin 100,000 IU/mL was used as a positive control, and 2.5% DMSO as a negative control. Microorganism identification was conducted using CHROMagar and hematoxylin-eosin staining. Results: No inhibition zones were observed in any of the extract treatments.. In contrast, Nystatin showed consistent inhibition zones with an average diameter above 17 mm, while DMSO showed no inhibitory effect. Morphological identification confirmed the test microorganism as Candida albicans. Conclusions: Red dragon fruit peel extract did not exhibit antifungal activity against Candida albicans in the well diffusion method. Further research is needed using different approaches and methodologies.KEY WORDS: Candida albicans, red dragon fruit, antifungal, flavonoid, well diffusion]]>
