Solamargine: The Main Glycoalkaloid from the Fruits of Solanum paludosum

The Genus Solanum: An Ethnopharmacological, Phytochemical and Biological Properties Review

Over the past 30 years, the genus Solanum has received considerable attention in chemical and biological studies. Solanum is the largest genus in the family Solanaceae, comprising of about 2000 species distributed in the subtropical and tropical regions of Africa, Australia, and parts of Asia, e.g., China, India and Japan. Many of them are economically significant species. Previous phytochemical investigations on Solanum species led to the identification of steroidal saponins, steroidal alkaloids, terpenes, flavonoids, lignans, sterols, phenolic comopunds, coumarins, amongst other compounds. Many species belonging to this genus present huge range of pharmacological activities such as cytotoxicity to different tumors as breast cancer (4T1 and EMT), colorectal cancer (HCT116, HT29, and SW480), and prostate cancer (DU145) cell lines. The biological activities have been attributed to a number of steroidal saponins, steroidal alkaloids and phenols. This review features 65 phytochemically studied species of Solanum between 1990 and 2018, fetched from SciFinder, Pubmed, ScienceDirect, Wikipedia and Baidu, using "Solanum" and the species' names as search terms ("all fields").

Molluscicidal activity of some BrazilianSolanumspp. (Solanaceae) againstBiomphalaria glabrata

Plants in the genus Solanum (Solanaceae) produce a great variety of steroidal saponins and glycoalkaloids that confer natural resistance against several pests. Methanolic extracts of 13 Solanum species have now been tested for molluscicidal activity against Biomphalaria glabrata. The extracts investigated were prepared from the fruit of S. asperum, S. capsicoides, S. palinacantum, S. paludosum, S. paniculatum, S. paraibanum and S. sisymbriifolium, the aerial parts of S. asperum, S. capsicoides, S. crinitum, S. diamantinense, S. megalonyx, S. palinacantum, S. paniculatum, S. sisymbriifolium and S. torvum, and the roots of S. asperum, S. asterophorum, S. palinacantum, S. paludosum, S. paniculatum and S. stipulaceum. Encouragingly, the extracts from S. asperum, S. diamantinese, S. paludosum, S. sisymbriifolium and S. stipulaceum showed significant molluscicidal activity, the median lethal concentrations recorded (20-50 microg/ml) falling well below the threshold, of 100 microg/ml, set for a potential molluscicide by the World Health Organization.

Molluscicidal activity of various solvent extracts from Solanum nigrum var. villosum L. aerial parts against Galba truncatula

Molluscicidal activity of Solanum nigrum var. villosum (morelle velue) extracts and their fractions were tested against the mollusca gastropoda Galba truncatula intermediate host of Fasciola hepatica. The results indicated that the hydro-methanol (MeOH-H₂O) immature fruit extract possess the highest molluscicidal activity (LC₅₀ = 3.96 mg/L) against Galba truncatula compared with other tested compounds. After acido-basic treatment, the methanolic extract fraction isolated from the immature fruits and the richest in alkaloids was the most toxic (LC₅₀ = 1.65 mg/L). The fractions richest in saponosides obtained from the hydromethanolic and methanolic extracts of immature fruits showed interesting molluscicidal activities (LC₅₀ = 6.15 mg/L and LC₅₀ = 7.91 mg/L, respectively). The observed molluscicide activity could be attributed to the presence of alkaloids or saponosides. So, the immature fruits of Solanum nigrum var. villosum could be substrates of choice for molluscicide activity. In addition, total alkaloids and saponosides present in this plant deserve further investigations in order to identify the active principles and demonstrate their activities on mollusks in their natural habitat. According to the World Health Organization’s guidelines on screening for plant molluscicides, use of these fractions may add to the arsenal of methods to control snail transmitting fasciolosis in tropical and Third World countries where fasciolosis is a common disease.

Bioactivities of glycoalkaloids and their aglycones from Solanum species

Potatoes, tomatoes, and aubergines are all species of the Solanum genus and contain a vast array of secondary metabolites including calystegine alkaloids, phenolic compounds, lectins, and glycoalkaloids. Glycoalkaloids have been the subject of many literature papers, occur widely in the human diet, and are known to induce toxicity. Therefore, from a food safety perspective further information is required regarding their analysis, toxicity, and bioavailability. This is especially important in crop cultivars derived from wild species to prevent glycoalkaloid-induced toxicity. A comprehensive review of the bioactivity of glycoalkaloids and their aglycones of the Solanum species, particularly focused on comparison of their bioactivities including their anticancer, anticholesterol, antimicrobial, anti-inflammatory, antinociceptive, and antipyretic effects, toxicity, and synergism of action of the principal Solanum glycoalkaloids, correlated to differences of their individual molecular structures is presented.

Molluscicidal activity of Solanum species of the Northeast of Brazil on Biomphalaria glabrata

Seven species of Solanum were screened for their molluscicidal properties against Biomphalaria glabrata, the intermediated host of Schistosoma mansoni, Solanum agrarium, S. jabrense, S. melissarum, S. megalonyx, S. paludosum, S. paraibanum and S. stipulaceum. Four extracts showed molluscicidal activity with LC(50) from 22 to 56 microg/ml.

Steroid alkaloid glycosides from Solanum robustum

Solamargine, solasonine, N-hydroxyrobustine and a new glycoalkaloid, N-hydroxysolamargine, has been isolated from the leaves of Solanum robustum, the structure of which has been elucidated as (25R)-3beta-{O-alpha-L-rhamnopyranosyl-(1-->2)-O-[alpha-L- rhamnopyranosyl- (1-->4)]-beta-D-glucopyranosyloxy}-22alphaN- spirosol-5-en-N-ol.