Ultraviolet (UV) Activation Effect on Antibacterial Agents of Red Betel (Piper Crocatum) Extract to Streptococcus mutans

Ultraviolet (UV) radiation has caused negative effect on biological environment. As non-moving living things, plants have their own response to reduce the negative effect by increasing flavonoid accumulation, such as red betel (Piper crocatum), which help the plant's protection from bacteria. In Indonesia, red betel has been used as a herb treatment, especially in oral treatment. This study aims to optimise the antibacterial effect of red betel extract on oral bacteria, Streptococcus mutans, by irradiating UV. Kirby-Bauer method of disk diffusion test was used on this study by showing the bacteria's diameter of inhibition zone. The samples distribution was devided into two groups, group (L-R+), control group, only used red betel extract without UV irradiation and group (L+R+) treatment combination of UV irradiation and red betel extract. The results showed that group L+R+ had better antibacterial effect on Streptococcus mutans, proven by the bigger inhibition zone, than group L-R+. UV irradiation for 12 hours showed the best result on each treatment with diameter of inhibition zone (15.00 ± 0.05) mm for 10 watt and (15.96 ± 0.05) mm for 15 watt. So, it is proven that UV irradiation can increase the antibacterial effect of red betel extract. © 2020 Published under licence by IOP Publishing Ltd

Rancang bangun medan listrik berpulsa dengan elektroda keping sejajar sebagai alat deaktifator bakteri: Studi kasus pada susu kemasan

INDONESIA: Susu salah satu makan pokok yang mudah terkontaminasi dengan bermacam-macam bakteri. Medan listrik berpulsa yang diaplikasikan pada elektroda keping sejajar dapat dimanfaatkan untuk mengurangi pertumbuhan bakteri. Penelitian ini bertujuan untuk mengetahui pengaruh frekuensi dan lama paparan terhadap proses pertumbuhan bakteri yang diterapkan pada bakteri Listeria monocytogeneses dan bakteri Salmonella typhimurium. Proses pembuatan alat dengan menggunakan IC 555 sebagai osilator dihubungkan ke trafo step up dan trafo high voltage. IC 555 digunakan sebagai timer dan dihubungkan dengan interuptor untuk memvariasikan nilai frekuensi. Alat mempunyai nilai tegangan keluaran 18 kV dan medan listrik 3,6 kV/cm. Pengambilan data dengan variasi frekuensi (15, 25, 50, dan 100 Hz) dan variasi waktu pemaparan (5, 10, 15, 20, dan 25 menit) dilakukan pada masing-masing bakteri. Hasil uji penelitian ini menunjukkan variasi frekuensi dan lama waktu paparan mempengaruhi pertumbuhan bakteri pada susu kemasan. Penghambatan pertumbuhan bakteri Listeria monocytogenes yang paling optimal pada frekuensi (100 Hz) dengan jumlah koloni (0,780 x 108 CFU/ml) dan waktu paparan (25 menit) dengan jumlah bakteri (0,409 x 108 CFU/ml). Pada bakteri Salmonella typhimurium yang paling optimal pada frekuensi (100 Hz) dengan jumlah bakteri (0,722 x 108 CFU/ml) dan waktu paparan (30 menit) dengan jumlah bakteri (0,8872 x 108 CFU/ml). Hal ini disebabkan membran seluler bakteri rusak, sehingga menyebabkan keluarnya materi intraseluler. Kerusakan membran seluler disebabkan oleh elektroporasi yang dapat meningkatkan potensial membran. Semakin tinggi frekuensi, maka meningkatkan tegangan transmembran semakin tinggi. ENGLISH: Milk is one of the staple foods which is easily contaminated by a variety of bacteria. Reduction of bacterial growth can use pulsed electric field is applied to the electrode chip parallel. This research aims to determine the effect of frequency and time exposure on bacterial growth (Listeria monocytogenes and Salmonella typhymurium bacteria). The instrument was set up using IC 555 as ocillator connected to step up transformer and high voltage transformer. IC 555 was used as timer and connected to interrupter oscillator to vary the frequency value. It was obtained voltage value (18 kV) and the output pulsed electric field (3,6 kV/cm) of each bacteries. The retrival data were made in frequency variation (15, 25, 50 and 100 Hz) and time exposure variation (5, 10, 15, 20 and 25 minutes) of bacteries. It was obtained variation of the frequency and the time exposure had effect on colonnies of bacteria growth. The most optimal frequency to decrease Listeria monocytogenes bacteria growth were 100 Hz, with the number bacteria (0,780 x 108 CFU/ml) and the exposure time was 25 minutes, with number bacteria (0,409 x 108 CFU/ml). The most optimal frequency to decrease Salmonella typhymurium bacteria growth were 100 Hz, with the number bacteria (0,722 x 108 CFU/ml) and the time exposure was 30 minutes with the number bacteria (0,887 x 108 CFU/ml). Due to a bacterial cell membranes induced by Electroporation, it increased the membrane potential. In conclusion the higher frequency, the higher transmembrane of voltage

Effectiveness of Photodynamic Inactivation with Exogenous Photosensitizer Curcuma longa Extract Activated by Laser Diode 403 nm on Staphylococcus Aureus

Photodynamic Inactivation (PDI) is a modality of antimicrobial therapy. Oxygen peroxidation in cell membranes has caused antimicrobial effects by inhibiting cell metabolism. The effectiveness of PDI depends on light sources, photosensitizer agents (Ps) and oxygen. This study is to investigate the antimicrobial effect of PDI using Curcuma longa (CL) extract as a photosensitizer (Ps) agent activated by 403 nm laser diode on Staphylococcus aureus (S. aureus). CL extract was prepared by maceration of turmeric rhizome using 96% ethanol with concentration 0.15% (Ps1) and 0.3% (Ps2), respectively. The samples were divided into three groups; control (C1), treatments with Ps1 (C2) and Ps2 (C2’), treatment with laser irradiations (T1), PDI treatment with Ps1 (T2) and Ps2 (T3). The bacterial growth has been monitored by ELISA reader and measured by Colony Counter. The percentage of bacterial reduction was analyzed by one-way ANOVA test. PDI treatment with CL extract is more effective to reduce S. aureus compared without exogenous CL extract. The highest reduction was given at high level irradiation with an energy density of 15.83 J/cm2 where treatment with Ps1 and Ps2 gave 79.18% and 85.48% reduction, respectively. Exogenous photosensitizer addition in PDI can increased bacterial reduction to 85.48% with 0.3% CL extracts at high level irradiation. CL extracts as exogenous photosensitizer activated by laser diode provides an increase the effectiveness of PDI on S. aureu