Solanum nigrescens

scientific name: 
Solanum nigrescens M. Martens & Galeotti
Botanical family: 

Botanical description

Anthers 1.7 mm or more in length; dull black or green mature fruit; calyx adhering to fruit; fruiting pedicels noticably deflexed; plants of highlands.

Herb, up to 1 m high; young stems pilose.  Leaves in pairs or solitary, of different sizes but similar appearance, entire or sinuate-dentate, ovate to ovate-lanceolate; apex acuminate, base attenuate.  Inflorescences internodal, racemose or subumbellate; corolla white or lilac, with a dark spot at the base of each lobe.  Fruit globose, 4-7 mm in diameter.



abnormal vaginal discharge:

  ripe leaf, cut at the end of or after fruition, decoction, applied locally, vaginal wash1

For abnormal vaginal discharge:

Prepare a decoction with 30 grams (10 spoonfuls) of ripe leaf in 1 liter (4 cups) of water. Boil for at least 10 minutes in a covered pot, allow to cool down and apply as sitz baths and vaginal washes11, 3 times a day1, during 15 days5.

Any medicinal preparation must be preserved cold and used within the 24 hours.

According to published and other information:

Use for abnormal vaginal discharge is classified as REC, based on the significant traditional use documented in the TRAMIL surveys, toxicity studies, scientific validation and available published scientific information.

For topical application, strict hygiene measures should be observed in order to avoid contamination or additional infection.

Should there be a notable worsening of the patient’s condition, or should the symptoms persist for more than 7 days, seek medical attention.

TRAMIL Research10

The aqueous extract (infusion) at doses of 5 g of dried leaf/kg, administered orally to mice, did not evidence signs of acute toxicity.

There are no pre-clinical toxicity data available on the use of the aerial parts for topical application.

There is no available information documenting the safety of local application to girls, or to pregnant or lactating women.

The leaf contains a saponin: cantalasaponin-32.

The phytochemical screening showed the presence of alkaloids, unsaturated polycyclic steroids, saponins, 2-deoxygenated sugars, tannins, cardenolides3.

The ethanolic extract (tincture) from the dried leaf at a (1:10) ratio (0.1 mL/disk) showed antimicrobial activity in vitro against Bacillus subtilis but not against Pseudomonas aeruginosa, Sreptococcus pyogenes,Proteus vulgaris, Salmonella typhi, Shigella flexneri4.  The same extract at a concentration of 30 µL/disk was active against Pseudomonas aeruginosa, Staphylococcus aureus and Candida albicans but inactive against Escherichia coli4.

The hydromethanolic extract (50%) from the dried plant (0.15 mL/disk) showed antimycotic activity in vitro against Candida albicans5.

The ethanolic extract (tincture) from the plant at a (1:10) ratio (1 mL/tube) showed fungicidal activity MIC = 100 to 300 mg against Microsporum canis, M.gypseum, Trichophyton mentagrophytes, T.rubrum but not against Epidermophyton floccosum6.

The hydroalcoholic maceration (45%) from the dried leaf was active in vitro against Cryptococcus neoformans, Candida albicans but not against Aspergillus fumigatus7.

The leaf decoction induced immunomodulating activity in mice, evidenced by an increase in the population of lymphocytes and serum antibody titer8.

A cream prepared with the ethanolic extract (50%) from the dried aerial parts (1:10) and topically applied 2 times/day/15 days to the vagina of 4-5 month-old female guinea pigs did not injure the epithelium, as evaluated through vaginal cytology with Papanicolau tinction every 2 days, and 15 and 30 days after treatment had finished.

Ovules prepared with the same ethanolic extract, with a base of Tween 80 and Carbowax 400, melted at 32 degrees Celsius, to which the ethanolic maceration (10% v/v) was added, kept at room temperature, or of commercial nystatin, were administered intravaginally 2 times/day/15 days to 2 groups of 50 non-pregnant women each, with Candida albicans vaginitis, confirmed by culture in Sabouraud medium.  The patients were evaluated by clinical, microscopic (Papanicolau smear) and microbiologic (culture in Sabouraud medium) 15 and 30 days after treatment had finished.  The ovule prepared with the ethanolic extract from the dried aerial parts cured (i.e. rendered a negative culture of) 45 patients (90%) while the nystatin ovule cured 47 patients (94%); there was no significant difference between the two groups5,9.

Fungicidal activity has been attributed to cantalasaponin-32.




1 GIRON L, 1988 Encuesta TRAMIL (Costa atlántica). Centro Mesoamericano de Tecnología CEMAT, Guatemala, Guatemala.

2 HE XG, MOCEK U, FLOSS HG, CACERES A, GIRON L, BUCKLEY H, COONEY G, MANNS J, WILSON BW, 1994 An antifungal compound from Solanum nigrescens. J Etnopharmacol 43(3):173-177.

3 GIRON L, 1983 Investigación de la inhibición de Candida albicans por preparaciones de plantas usadas en la medicina popular (Tesis Mag. Sc). Fac Ciencias Químicas y Farmacéuticas, Universidad de San Carlos de Guatemala USAC, Guatemala, Guatemala.

4 CACERES A, GIRON L, ALVARADO S, TORRES M, 1987 Screening of antimicrobial activity of plants popularly used in Guatemala for the treatment of dermatomucosal diseases. J Ethnopharmacol20(3):223-237.

5 GIRON LM, AGUILAR GA, CACERES A, ARROYO GL, 1988 Anticandidal activity of plants used for the treatment of vaginitis in Guatemala and clinical trial of a Solanum nigrescens preparation. J Etnopharmacol 22(3):307-313.

6 CACERES A, LOPEZ BR, GIRON MA, LOGEMANN H, 1991 Plants used in Guatemala for the treatment of dermatophytic infections. 1. Screening for antimycotic activity of 44 plant extracts. J Ethnopharmacol 31(3):263-276.

7 COONEY G., BUCKLEY H, BRICKUS T, CACERES A, 1991 Fungicidal activity of aSolanum plant extract from Guatemala, CA. Pharmacy World Congress, Washington, USA. CS 52.

8 LARA R, SANDOVAL H, JIMENEZ M, DE LA ROCA D, GUZMAN A, 1991 Determinación de la actividad inmunomoduladora de los extractos de zarzaparrilla, quilete y pericón. IV Congreso Nacional de Microbiología, Guatemala, Guatemala.

9 AGUILAR G, 1985 Tratamiento de la candidosis vaginal con extracto deSolanum nigrescens (Tesis Mag. Sc). Fac Ciencias Químicas y Farmacéuticas, Universidad de San Carlos de Guatemala USAC, Guatemala, Guatemala.

10 GIRON L, 1992 Toxicidad aguda del extracto acuoso de Solanum nigrescens. Informe TRAMIL. FARMAYA, Guatemala, Guatemala.

11 GIRON L, CACERES A, FREIRE V, ALONZO A, SALVADOR L, 1995 Folleto informativo sobre algunas plantas comúnmente utilizadas por la población Garifuna de Livingston, Guatemala, Guatemala, p45.


The information provided is for educational purposes only for the benefit of the general public and health professionals. It is not intended to take the place of either the written law or regulations. Since some parts of plants could be toxic, might induce side effects, or might have interactions with certain drugs, anyone intending to use them or their products must first consult with a physician or another qualified health care professional. TRAMIL has no responsibility whatsoever towards the user for any decision, action or omission made in relation to the information contained in this Pharmacopoeia.