Table 4. Antibacterial activity of mangostin bulk extracts recovered by virgin coconut oil (VCO), mixed VCO-prolylene glycol (PG) and PG compared to their corresponding nanoemulsions.
| Antibacterial activity | Extractant | MIC values (mg/mL) | |
|---|---|---|---|
| Bulk extract | Nanoemulsions* | ||
| E. coli1 | VCO | 3.13 | 1.56 |
| Mixed VCO-PG | 1.56 | 0.79 | |
| PG | 1.56 | 0.79 | |
| S. aureus2 | VCO | 1.56 | 0.79 |
| Mixed VCO-PG | 1.56 | 0.79 | |
| PG | 3.13 | 1.56 | |
Values are given as mean from triplicate determinations.
1MIC value against E. coli of ampicillin was 4 μg/mL.
2MIC value against S. aureus of ampicillin was 4 μg/mL.
*Emulsions were prepared using 10% (w/w) mixed emulsifiers (Span 20 and Tween 20; HLB = 15.1) and 10% crude mangostin extracts using a high-speed homogenizer (15,000 rpm) for 5 min and an ultrasonic homogenization (20 kHz, 750 Watts, 70% amplitude) for 10 min.