4.1.
Antibacterial
| Natural product compounds | Chemical Class | Plant source | Antibacterial activity |
Proposed Mechanism | Other biological activity | Refs. | ||
|---|---|---|---|---|---|---|---|---|
| Bacterial target | Activity (MIC) | Derivative activity (MIC) | ||||||
| Piperine (1) Piperlongumine (2) |
Amide Alkaloids | Piper species |
S. aureus
P. aeruginosa |
(1) 3.9–15.6 µg/mL (2) 3.9–31.2 µg/mL |
(1a–1e) 0.15–0.36 µM (M. tuberculosis) | – | Anti-tumor, antifungal. analgesic, and antidepressant Host targeted mechanism: Increased mTORC1 signaling leading to increased bacterial clearance by macrophages |
30
31 |
|
| ||||||||
| Biochanin A (15) | Flavonoids | Fabaceae species | P. aeruginosa | 0.97 µg/mL | – | – | Antidiabetic, anticancer | 82 |
|
| ||||||||
| Acacetin (16) | Flavonoids | Fabaceae species | P. aeruginosa | 3.90 µg/mL | – | – | MAO-A/B inhibitor | 82 |
|
| ||||||||
| Flavonoids (Isoflavonoids, flavones) Myrsininone A (17) (18) (6) |
Flavonoids (17, 18) Anthraquinone (6) |
Ficus auriculata (Lour.) (17) Ficus auriculata (Lour.) (18) Stereospermum fimbriatum (Wall. Ex G. Don) (6) |
various various MRSA |
1.25–10 µM (17) 10–20 µM 6.25 µg/mL |
- | Potentially through nonspecific action upon the bacterial cell membrane (17) Unknown (18–19) |
α-glucosidase inhibition IC50 50.5 ± 3.7 µM (17) |
84
49 |
|
| ||||||||
| Carnosic acid and derivatives Carnosic acid (29) |
Diterpenoids | Lepechinia meyenii (Walp.) |
E. faecalis, various MRSA strains |
15.6, 7.8–15.6 µg/mL | Anti-MRSA activity; (30), 31.2 µg/mL; (31) 3.9 µg/mL | Interaction with bacterial membrane phospholipids | Antioxidant and anti-adipogenic | 125 |
|
| ||||||||
| Triterpenic derivatives (34–38) |
Terpenoids | various | S. aureus | (34–38) 0.15 µM | – | Disrupts S. aureus cell membrane and inhibits NADH oxidation | – | 139 |
|
| ||||||||
| Oleanolic acid derivative (39) |
Terpenoids | various | S. aureus | 4 µg/mL (MRSA) | – | Deregulate peptidoglycan metabolism | Anti-chlamydial activity | 141 |