Antibacterial activity test of nipah leaf extract (Nypa fruticans Wurmb) in inhibiting the growth of Lactobacillus acidophilus ATCC 4356 on the surface of hot-polymerized acrylic resin: Study experimental

Ferdina, Resa
Azzahra, Nadya Alifia
Hadi, Azmil
Sari, Widya Puspita

Padjadjaran Journal of Dental Researchers and Students
Vol 10, No 3 (2026): Oktober 2026

ABSTRACTIntroduction: Heat-polymerized acrylic resin is the most commonly used material for denture bases. Its porous and rough surface characteristics may facilitate the adhesion of microorganisms such as Lactobacillus acidophilus, thereby increasing the risk of denture stomatitis. Chemical denture cleansers such as sodium hypochlorite are effective disinfectants; however, they may damage the surface of acrylic resin. Therefore, a safer natural alternative is needed, such as nipah leaf extract (Nypa fruticans Wurmb.), which has antibacterial potential. This study aimed to evaluate the antibacterial activity of nipah leaf extract in inhibiting the growth of Lactobacillus acidophilus ATCC 4356 on the surface of heat-polymerized acrylic resin. Methods: This study was a laboratory experimental study using a post-test only control group design. A total of 25 heat-polymerized acrylic resin specimens were prepared. The sample size was calculated using Federer's formula (t−1)(r−1)≥15, resulting in five replications for each group. The specimens were divided into groups treated with 10%, 15%, and 20% nipah leaf extract, along with positive and negative control groups. Bacterial growth was measured using the UV–Vis spectrophotometric method. Data were analyzed using the Shapiro–Wilk test, Levene's test, One-Way ANOVA, and Tukey's HSD post hoc test. Results: The results showed a significant difference in Lactobacillus acidophilus growth among the treatment groups (p<0.05). Nipah leaf (Nypa fruticans Wurmb.) extract at a concentration of 20% showed the greatest inhibitory effect on bacterial growth compared with the other concentrations. Conclusion: Nipah leaf extract (Nypa fruticans Wurmb.) showed antibacterial activity against Lactobacillus acidophilus ATCC 4356 on the surface of heat-polymerized acrylic resin and may have potential as a natural alternative for denture cleaning.KEYWORDS: Antibacterial activity, nipah leaf (Nypa fruticans Wurmb) extract, Lactobacillus acidophilus, heat-polymerized acrylic resinUji aktivitas antibakteri ekstrak daun nipah dalam menghambat pertumbuhan Lactobacillus acidophilus ATCC 4356 pada permukaan resin akrilik polimerisasi panas: Studi eksperimentalABSTRAKPendahuluan: Resin akrilik polimerisasi panas merupakan bahan yang paling sering digunakan sebagai basis gigi tiruan. Sifat porositas dan kekasaran permukaannya dapat mempermudah perlekatan mikroorganisme, salah satunya Lactobacillus acidophilus, sehingga meningkatkan risiko terjadinya denture stomatitis. Pembersih gigi tiruan berbahan kimia seperti sodium hipoklorit efektif sebagai desinfektan, tetapi berpotensi merusak permukaan resin akrilik. Berdasarkan kondisi tersebut, diperlukan alternatif bahan pembersih alami yang lebih aman, salah satunya ekstrak daun nipah (Nypa fruticans Wurmb.) yang diketahui memiliki aktivitas antibakteri. Penelitian ini bertujuan untuk menganalisis aktivitas antibakteri ekstrak Nypa fruticans Wurmb. dalam menghambat pertumbuhan Lactobacillus acidophilus ATCC 4356 pada permukaan resin akrilik polimerisasi panas. Metode: Jenis penelitian ini adalah eksperimental laboratoris dengan rancangan post-test only control group design. Jumlah sampel penelitian sebanyak 25 plat resin akrilik polimerisasi panas yang ditentukan berdasarkan rumus Federer (t-1)(r-1)≥15, sehingga diperoleh lima kali pengulangan pada masing-masing kelompok perlakuan. Sampel dibagi ke dalam kelompok ekstrak Nypa fruticans Wurmb. konsentrasi 10%, 15%, dan 20%, kelompok kontrol positif, serta kontrol negatif. Pertumbuhan bakteri diukur menggunakan metode spektrofotometri UV-Vis. Data dianalisis menggunakan uji Shapiro-Wilk, uji Levene, uji One Way ANOVA, dan uji lanjut Tukey HSD. Hasil: Hasil penelitian menunjukkan adanya perbedaan yang bermakna pada pertumbuhan Lactobacillus acidophilus antar kelompok perlakuan (p < 0,05). Ekstrak Nypa fruticans Wurmb. pada konsentrasi 20% menunjukkan daya hambat paling tinggi terhadap pertumbuhan bakteri dibandingkan konsentrasi lainnya. Simpulan: Ekstrak Nypa fruticans Wurmb memiliki aktivitas antibakteri dalam menghambat pertumbuhan Lactobacillus acidophilus ATCC 4356 pada permukaan resin akrilik polimerisasi panas dan berpotensi digunakan sebagai alternatif bahan pembersih gigi tiruan alami.KATA KUNCI: aktivitas antibakteri, ekstrak Nypa fruticans Wurmb, Lactobacillus acidophilus, resin akrilik polimerisasi panas.