Efek antibakteri ekstrak kelopak bunga rosella terhadap jumlah koloni Streptococcus sp.Antibacterial effect of the rosella flower extract towards the Streptococcus sp. colonies - Lisna Unita; Esterlina Singarimbun (Jurnal Kedokteran Gigi Universitas Padjadjaran, 2018)
Pendahuluan: Tanaman herbal rosella (Hibiscus sabdariffa L.) mempunyai manfaat dalam bidang kesehatan, terutama pada bagian kelopak bunganya (sepal) yang merupakan bagian komersial. Tanaman ini memiliki aktivitas antibakterial dalam menghambat pertumbuhan bakteri gram positif dan bakteri gram negatif. Ekstrak kelopak bunga rosella (Hibiscus sabdariffa L.) mempunyai aktivitas antibakteri terhadap bakteri gram positif yaitu pada bakteri Streptococcus sp. Tujuan penelitian ini adalah untuk mengetahui jumlah koloni Streptococcus sp. dari beberapa konsentrasi ekstrak etanol kelopak bunga rosella (Hibiscus sabdariffa L.). Metode: Eksperimental laboratorium dengan rancangan Post Test Only Control Group Design dan terdiri atas 5 kelompok perlakuan yaitu kelompok ekstrak kelopak bunga rosella (konsentrasi 40%, 20%, 10%, dan 5%) serta kelompok kontrol negatif (DMSO). Masing-masing perlakuan dilakukan 5 kali pengulangan. Penghitungan jumlah koloni Streptococcus sp. menggunakan metode TPC (Total Plate Count) pada media Mueller Hinton Agar (MHA). Data dianalisis menggunakan Uji Kruskal Wallis (p<0,05) dilanjutkan dengan LSD. Hasil: Berdasarkan uji LSD, terdapat perbedaan jumlah koloni Streptococcus sp. dari setiap kelompok perlakuan. Ekstrak kelopak bunga rosella (Hibiscus sabdariffa L.) pada konsentrasi 40%, 20%, dan 10% memiliki rata-rata jumlah koloni yang sama 0 ± 0. Konsentrasi 5% rata-ratanya 60,60 ± 33,299, pada kelompok kontrol (DMSO) 1013,80 ± 430,667 dan terdapat perbedaan yang signifikan (p<0,05)  antara jumlah koloni Streptococcus sp. dari konsentrasi 40%, 20%, 10% dan 5% dengan DMSO; dimana nilai p = 0,0001. Simpulan: Konsentrasi 5% menunjukkan nilai Kadar Hambat Minimum (KHM) sedangkan pada konsentrasi 10% menunjukkan nilai Kadar Bunuh Minimum (KBM) dari ekstrak kelopak bunga rosella terhadap Streptococcus sp.Kata kunci: Koloni, rosella, Streptococcus sp. ABSTRACTIntroduction: Roselle herbs plant (Hibiscus sabdariffa L.) can be used in the medical field, especially the petals, which has become the commercial parts. This plant has antibacterial activity in inhibiting the growth of both gram-positive and gram-negative bacteria. The ethanolic extract of roselle (Hibiscus sabdariffa L.) petals has antibacterial activity towards gram-positive bacteria such as Streptococcus sp. The purpose of this study was to determine the amount of Streptococcus sp. colonies in different concentrations of roselle (Hibiscus sabdariffa L.) petal extract. Methods: This study was an experimental laboratory with post test only control group design consisted of 5 treatment groups, which was roselle petal extract group (concentration of 40%, 20%, 10%, and 5% respectively) and negative control group (DMSO). Each treatment was performed with 5 times repetition. The amount of Streptococcus sp. colonies was count using the TPC (Total Plate Count) method on Mueller Hinton Agar (MHA) media. Data obtained were analysed using the Kruskal Wallis test (p < 0.05) followed by LSD test. Result: Based on the LSD test result showed that there was a difference in the amount of Streptococcus sp. colonies in each treatment group. The extract of roselle (Hibiscus sabdariffa L.) petals at 40%, 20%, and 10% concentrations had the same average amount of colonies, which was 0 ± 0. The average number of colonies in 5% concentration was 60.60 ± 33.299, and in the control group (DMSO) was 1013.80 ± 430,667; and there was a significant difference (p <.0.05) between the amount of Streptococcus sp. colonies from 40%, 20%, 10% and 5% concentrations with DMSO; where the p-value = .0.001. Conclusion: Roselle petals extract with 5% concentration showed the  Minimum Inhibitory Concentration (MIC) value while at 10% concentration showed the Minimum Killing Concentration (MKC) value towards Streptococcus sp.Keywords: Colonies, roselle, Streptococcus sp.