TABLE 1.
Plants containing antimicrobial activitya
| Common name | Scientific name | Compound | Class | Activityd | Relative toxicityb | Reference(s)c |
|---|---|---|---|---|---|---|
| Alfalfa | Medicago sativa | ? | Gram-positive organisms | 2.3 | ||
| Allspice | Pimenta dioica | Eugenol | Essential oil | General | 2.5 | |
| Aloe | Aloe barbadensis, Aloe vera | Latex | Complex mixture | Corynebacterium, Salmonella, Streptococcus, S. aureus | 2.7 | 136 |
| Apple | Malus sylvestris | Phloretin | Flavonoid derivative | General | 3.0 | 101 |
| Ashwagandha | Withania somniferum | Withafarin A | Lactone | Bacteria, fungi | 0.0 | |
| Aveloz | Euphorbia tirucalli | ? | S. aureus | 0.0 | ||
| Bael tree | Aegle marmelos | Essential oil | Terpenoid | Fungi | 179 | |
| Balsam pear | Momordica charantia | ? | General | 1.0 | ||
| Barberry | Berberis vulgaris | Berberine | Alkaloid | Bacteria, protozoa | 2.0 | 140, 163 |
| Basil | Ocimum basilicum | Essential oils | Terpenoids | Salmonella, bacteria | 2.5 | 241 |
| Bay | Laurus nobilis | Essential oils | Terpenoids | Bacteria, fungi | 0.7 | |
| Betel pepper | Piper betel | Catechols, eugenol | Essential oils | General | 1.0 | |
| Black pepper | Piper nigrum | Piperine | Alkaloid | Fungi, Lactobacillus, Micrococcus, E. coli, E. faecalis | 1.0 | 78 |
| Blueberry | Vaccinium spp. | Fructose | Monosaccharide | E. coli | 158 | |
| Brazilian pepper tree | Schinus terebinthifolius | Terebinthone | Terpenoids | General | 1.0 | |
| Buchu | Barosma setulina | Essential oil | Terpenoid | General | 2.0 | |
| Burdock | Arctium lappa | Polyacetylene, tannins, terpenoids | Bacteria, fungi, viruses | 2.3 | ||
| Buttercup | Ranunculus bulbosus | Protoanemonin | Lactone | General | 2.0 | |
| Caraway | Carum carvi | Coumarins | Bacteria, fungi, viruses | 24, 26, 83, 193 | ||
| Cascara sagrada | Rhamnus purshiana | Tannins | Polyphenols | Viruses, bacteria, fungi | 1.0 | |
| Anthraquinone | ||||||
| Cashew | Anacardium pulsatilla | Salicylic acids | Polyphenols | P. acnes | ||
| Bacteria, fungi | 91 | |||||
| Castor bean | Ricinus communis | ? | General | 0.0 | ||
| Ceylon cinnamon | Cinnamomum verum | Essential oils, others | Terpenoids, tannins | General | 2.0 | |
| Chamomile | Matricaria chamomilla | Anthemic acid | Phenolic acid | M. tuberculosis, S. typhimurium, S. aureus, helminths | 2.3 | 26, 83, 193 |
| — | Coumarins | Viruses | 24 | |||
| Chapparal | Larrea tridentata | Nordihydroguaiaretic acid | Lignan | Skin bacteria | 2.0 | |
| Chili peppers, paprika | Capsicum annuum | Capsaicin | Terpenoid | Bacteria | 2.0 | 42, 107 |
| Clove | Syzygium aromaticum | Eugenol | Terpenoid | General | 1.7 | |
| Coca | Erythroxylum coca | Cocaine | Alkaloid | Gram-negative and -positive cocci | 0.5 | |
| Cockle | Agrostemma githago | ? | General | 1.0 | ||
| Coltsfoot | Tussilago farfara | ? | General | 2.0 | ||
| Coriander, cilantro | Coriandrum sativum | ? | Bacteria, fungi | |||
| Cranberry | Vaccinium spp. | Fructose | Monosaccharide | Bacteria | 17, 158, 159 | |
| Other | ||||||
| Dandelion | Taraxacum officinale | ? | C. albicans, S. cerevisiae | 2.7 | ||
| Dill | Anethum graveolens | Essential oil | Terpenoid | Bacteria | 3.0 | |
| Echinacea | Echinaceae angustifolia | ? | General | 153 | ||
| Eucalyptus | Eucalyptus globulus | Tannin | Polyphenol | Bacteria, viruses | 1.5 | |
| — | Terpenoid | |||||
| Fava bean | Vicia faba | Fabatin | Thionin | Bacteria | ||
| Gamboge | Garcinia hanburyi | Resin | General | 0.5 | ||
| Garlic | Allium sativum | Allicin, ajoene | Sulfoxide | General | 150, 187, 188 | |
| Sulfated terpenoids | 250 | |||||
| Ginseng | Panax notoginseng | Saponins | E. coli, Sporothrix schenckii, Staphylococcus, Trichophyton | 2.7 | ||
| Glory lily | Gloriosa superba | Colchicine | Alkaloid | General | 0.0 | |
| Goldenseal | Hydrastis canadensis | Berberine, hydrastine | Alkaloids | Bacteria, Giardia duodenale, trypanosomes | 2.0 | 73 |
| Plasmodia | 163 | |||||
| Gotu kola | Centella asiatica | Asiatocoside | Terpenoid | M. leprae | 1.7 | |
| Grapefruit peel | Citrus paradisa | Terpenoid | Fungi | 209 | ||
| Green tea | Camellia sinensis | Catechin | Flavonoid | General | 2.0 | |
| Shigella | 235 | |||||
| Vibrio | 226 | |||||
| S. mutans | 166 | |||||
| Viruses | 113 | |||||
| Harmel, rue | Peganum harmala | ? | Bacteria, fungi | 1.0 | ||
| Hemp | Cannabis sativa | β-Resercyclic acid | Organic acid | Bacteria and viruses | 1.0 | |
| Henna | Lawsonia inermis | Gallic acid | Phenolic | S. aureus | 1.5 | |
| Hops | Humulus lupulus | Lupulone, humulone | Phenolic acids | General | 2.3 | |
| — | (Hemi)terpenoids | |||||
| Horseradish | Armoracia rusticana | Terpenoids | General | |||
| Hyssop | Hyssopus officinalis | — | Terpenoids | Viruses | ||
| (Japanese) herb | Rabdosia trichocarpa | Trichorabdal A | Terpene | Helicobacter pylori | 108 | |
| Lantana | Lantana camara | ? | General | 1.0 | ||
| — | Lawsonia | Lawsone | Quinone | M. tuberculosis | — | |
| Lavender-cotton | Santolina chamaecyparissus | ? | Gram-positive bacteria, Candida | 1.0 | 213 | |
| Legume (West Africa) | Millettia thonningii | Alpinumisoflavone | Flavone | Schistosoma | 175 | |
| Lemon balm | Melissa officinalis | Tannins | Polyphenols | Viruses | 245 | |
| Lemon verbena | Aloysia triphylla | Essential oil | Terpenoid | Ascaris | 1.5 | |
| ? | E. coli, M. tuberculosis, S. aureus | |||||
| Licorice | Glycyrrhiza glabra | Glabrol | Phenolic alcohol | S. aureus, M. tuberculosis | 2.0 | |
| Lucky nut, yellow | Thevetia peruviana | ? | Plasmodium | 0.0 | ||
| Mace, nutmeg | Myristica fragrans | ? | General | 1.5 | ||
| Marigold | Calendula officinalis | ? | Bacteria | 2.7 | ||
| Mesquite | Prosopis juliflora | ? | General | 1.5 | ||
| Mountain tobacco | Arnica montana | Helanins | Lactones | General | 2.0 | |
| Oak | Quercus rubra | Tannins | Polyphenols | |||
| Quercetin (available commercially) | Flavonoid | 113 | ||||
| Olive oil | Olea europaea | Hexanal | Aldehyde | General | 120 | |
| Onion | Allium cepa | Allicin | Sulfoxide | Bacteria, Candida | 239 | |
| Orange peel | Citrus sinensis | ? | Terpenoid | Fungi | 209 | |
| Oregon grape | Mahonia aquifolia | Berberine | Alkaloid | Plasmodium | 2.0 | 163 |
| Trypansomes, general | 73 | |||||
| Pao d’arco | Tabebuia | Sesquiterpenes | Terpenoids | Fungi | 1.0 | |
| Papaya | Carica papaya | Latex | Mix of terpenoids, organic acids, alkaloids | General | 3.0 | 34, 168, 191 |
| Pasque-flower | Anemone pulsatilla | Anemonins | Lactone | Bacteria | 0.5 | |
| Peppermint | Mentha piperita | Menthol | Terpenoid | General | ||
| Periwinkle | Vinca minor | Reserpine | Alkaloid | General | 1.5 | |
| Peyote | Lophophora williamsii | Mescaline | Alkaloid | General | 1.5 | |
| Poinsettia | Euphorbia pulcherrima | ? | General | 0.0 | ||
| Poppy | Papaver somniferum | Opium | Alkaloids and others | General | 0.5 | |
| Potato | Solanum tuberosum | ? | Bacteria, fungi | 2.0 | ||
| Prostrate knotweed | Polygonum aviculare | ? | General | 2.0 | ||
| Purple prairie clover | Petalostemum | Petalostemumol | Flavonol | Bacteria, fungi | 100 | |
| Quinine | Cinchona sp. | Quinine | Alkaloid | Plasmodium spp. | 2.0 | |
| Rauvolfia, chandra | Rauvolfia serpentina | Reserpine | Alkaloid | General | 1.0 | |
| Rosemary | Rosmarinus officinalis | Essential oil | Terpenoid | General | 2.3 | |
| Sainfoin | Onobrychis viciifolia | Tannins | Polyphenols | Ruminal bacteria | 105 | |
| Sassafras | Sassafras albidum | ? | Helminths | 2.0 | ||
| Savory | Satureja montana | Carvacrol | Terpenoid | General | 2.0 | 6 |
| Senna | Cassia angustifolia | Rhein | Anthraquinone | S. aureus | 2.0 | |
| Smooth hydrangea, seven barks | Hydrangea arborescens | ? | General | 2.3 | ||
| Snakeplant | Rivea corymbosa | ? | General | 1.0 | ||
| St. John’s wort | Hypericum perforatum | Hypericin, others | Anthraquinone | General | 1.7 | |
| Sweet flag, calamus | Acorus calamus | ? | Enteric bacteria | 0.7 | ||
| Tansy | Tanacetum vulgare | Essential oils | Terpenoid | Helminths, bacteria | 2.0 | |
| Tarragon | Artemisia dracunculus | Caffeic acids, tannins | Terpenoid | Viruses, helminths | 2.5 | |
| Polyphenols | 245 | |||||
| Thyme | Thymus vulgaris | Caffeic acid | Terpenoid | Viruses, bacteria, fungi | 2.5 | |
| Thymol | Phenolic alcohol | |||||
| Tannins | Polyphenols | |||||
| — | Flavones | |||||
| Tree bard | Podocarpus nagi | Totarol | Flavonol | P. acnes, other gram-positive bacteria | 123 | |
| Nagilactone | Lactone | Fungi | 121 | |||
| 122 | ||||||
| Tua-Tua | Jatropha gossyphiifolia | ? | General | 0.0 | ||
| Turmeric | Curcuma longa | Curcumin | Terpenoids | Bacteria, protozoa | 14 | |
| Turmeric oil | ||||||
| Valerian | Valeriana officinalis | Essential oil | Terpenoid | General | 2.7 | |
| Willow | Salix alba | Salicin | Phenolic glucoside | |||
| Tannins | Polyphenols | |||||
| Essential oil | Terpenoid | |||||
| Wintergreen | Gaultheria procumbens | Tannins | Polyphenols | General | 1.0 | |
| Woodruff | Galium odoratum | — | Coumarin | General | 3.0 | 26, 83, 193 |
| Viruses | 24 | |||||
| Yarrow | Achillea millefolium | ? | Viruses, helminths | 2.3 | ||
| Yellow dock | Rumex crispus | ? | E. coli, Salmonella, Staphylococcus | 1.0 |
a
Plants with activity only against HIV are listed in Table 6.
b
0, very safe; 3, very toxic. Data from reference 58.
d
“General” denotes activity against multiple types of microorganisms (e.g., bacteria, fungi, and protozoa), and “bacteria” denotes activity against gram-positive and gram-negative bacteria.