Solasonine

Phytochemistry. 1994 Nov;37(4):1007-11.

Interactions between the glycoalkaloids solasonine and solamargine in relation to inhibition of fungal growth.[Pubmed: 7765652]

Inhibition of mycelium development in Phoma medicaginis and Rhizoctonia solani by solamargine and Solasonine generally increased with increasing pH. P. medicaginis was the more susceptible species and solamargine the more potent compound.
METHODS AND RESULTS:
Solasonine was inactive against R. solani over the tested pH range (5-8). Dose-response curves confirmed these differential effects. Solamargine caused 50% growth inhibition in P. medicaginis at 60 microM (at pH 7) whereas no other treatment achieved this effect at 100 microM. Combinations of 50 microM of each glycoalkaloid produced synergistic effects against both fungi, especially R. solani which was essentially unaffected by either compound, by significantly inhibited by a 1:1 mixture of the two. The magnitude of the synergism was not affected by a pH change between 6 and 7. Spore germination in Alternaria brassicicola was markedly inhibited by 100 microM solamargine but unaffected by 100 microM Solasonine or either compound at 50 microM. In P. medicaginis, neither glycoalkaloid was inhibitory up to 150 microM.
CONCLUSIONS:
In combination, the two compounds caused synergistic effects in both species, but to a much greater extent in A. brassicicola.

Food Chem . 2013 Nov 15;141(2):1181-6.

Purification, antitumor activity in vitro of steroidal glycoalkaloids from black nightshade (Solanum nigrum L.)[Pubmed: 23790901]

Abstract Six steroidal glycoalkaloids (1-6) were isolated and purified from Solanum nigrum L. (SNL) by acid extraction and alkaline precipitation, various chromatographic techniques, and their structures were elucidated by spectroscopic data. Antitumor activity, structure-activity and its molecular mechanism were investigated by methyl thiazolyl tetrazolium (MTT) method, flow cytometry, colorimetric assay and an immunocytochemical method. Experimental results showed that compounds 1 (Solasonine), 2 (β1-Solasonine), 3 (solamargine) and 6 (solanigroside P) have cytotoxicity to MGC-803 cells. Compounds with three sugar units and a-l-rhamnopyranose at C-2 or a hydroxyl group on the steroidal backbone may be potential candidates for the treatment of gastric cancer. The mechanism of action may be related to the decrease of mutation p53, the increase of the ratio of Bax to Bcl-2 and the activation of caspase-3 to induce apoptosis.

Chem Biodivers. 2013 Apr;10(4):642-8.

In vitro leishmanicidal and cytotoxic activities of the glycoalkaloids from Solanum lycocarpum (Solanaceae) fruits.[Pubmed: 23576350]

Leishmaniasis is an infection caused by a protozoan parasite of the genus Leishmania and is the second most prevalent parasitic protozoal disease after malaria in the world.
METHODS AND RESULTS:
We report the in vitro leishmanicidal activity on promastigote forms of Leishmania amazonensis and cytotoxicity, using LLCMK2 cells, of the glycoalkaloids from the fruits of Solanum lycocarpum, determined by colorimetric methods. The alkaloidic extract was obtained by acid-base extraction; solamargine and Solasonine were isolated by silica-gel chromatography, followed by reversed-phase HPLC final purification. The alkaloidic extract, solamargine, Solasonine, as well as the equimolar mixture of the glycoalkaloids solamargine and Solasonine displayed leishmanicidal activity against promastigote forms of L. amazonensis, whereas the aglycone solasodine was inactive. After 24 and 72 h of incubation, most of the samples showed lower cytotoxicities (IC50 6.5 to 124 μM) as compared to leishmanicidal activity (IC50 1.1 to 23.6 μM). The equimolar mixture solamargine/Solasonine was the most active with an IC50 value of 1.1 μM, after 72 h. Likewise, solamargine was the most active after 24 h with an IC50 value of 14.4 μM, both in comparison with the positive control amphotericin B.