Green Synthesis of Silver Nanoparticles using Moringa oleifera: Implementation to Photoantimicrobial of Candida albicans with LED Light

Green synthesis of silver nanoparticles using Moringa oleifera (AgNPs/MO) was carried out to produce nanoscale antifungal agents which are used as photosensitizing agents in photoantimicrobial therapy. This study focused on investigating the potential of AgNPs/MO producing some toxic radical compounds that inhibit the growth of Candida albicans biofilms. The inhibition mechanism uses the principle of photoinactivation treatment which combines a photosensitizer with an LED light source at a power of 100 mW for 60 - 300 s of exposure. Quantitative data analyzed were the number of viable cells and radical compounds, formed by malondialdehyde (MDA) level. It is investigated through staining the XTT (2,3-Bis-(2-Methoxy-4-Nitro-5-Sulfophenyl)-2H-Tetrazolium-5-Carboxanilide) and TBARS (Thiobarbituric Acid Reactive Substances). The results show that the maximum wavelength of AgNPs is 440 nm while the Moringa oleifera has 2 peaks at 425 and 635 nm. The maximum effect occurred in the group of photosensitizer AgNPs/MO combined LED with percentage inactivation about 76.80 % for blue LEDs and 76.20 % for red LEDs. The group of LED irradiation without photosensitizer obtained about 51.85 % for blue LEDs and 50.04 % for red LEDs. The MDA level group of AgNPs/MO combined LED also produced MDA levels of 1.772 nmol/mL for blue LED and 1.617 nmol/mL for red LED. Meanwhile, the application of photoantimicrobial using only LEDs produced MDA levels of only 1.353 nmol/mL for blue LEDs and 1.347 nmol/mL for red LEDs. This research has shown that the green synthesis of AgNPs/MO has a good potential to inhibit the growth of Candida albicans biofilms as a photosensitizer agent. HIGHLIGHTS Silver nanoparticles (AgNPs) combined with Moringa oleifera (MO) extract have been shown to have potential as a photosensitizer to inhibit the growth of Candida albicans Green synthesis AgNPs/MO have a characteristic spectrum at 440 nm which is close to the blue light spectrum. Green synthesis AgNPs/MO combined with LED light irradiation energy can reduce the cell viability of Candida albicans up to 76.80 % through the XTT assay staining test method and produce 1.772 nmol/mL of Malondialdehyde that reacts with ROS compounds to cause cell damage. GRAPHICAL ABSTRACT