Ontogeny and organ-specific steroidal glycoside diversity is associated with differential expression of steroidal glycoside pathway genes in two Solanum dulcamara leaf chemotypes.

Solanaceous plants, such as Solanum dulcamara, produce steroidal glycosides (SGs). Leaf SG profiles vary among S. dulcamara individuals, leading to distinct phytochemical phenotypes ('chemotypes') and intraspecific phytochemical diversity ('chemodiversity'). However, if and how SG chemodiversity varies among organs and across ontogeny, and how this relates to SG metabolism gene expression is unknown. Among organs and across ontogeny, S. dulcamara plants with saturated (S) and unsaturated (U) SG leaf chemotypes were selected and clonally propagated. Roots, stems and leaves were harvested from vegetative and flowering plants. Extracts were analysed using untargeted LC-MS. Expression of candidate genes in SG metabolism (SdGAME9, SdGAME4, SdGAME25, SdS5αR2 and SdDPS) was analysed using RT-qPCRs. Our analyses showed that SG chemodiversity varies among organs and across ontogeny in S. dulcamara; SG richness (Dmg) was higher in flowering than vegetative plants. In vegetative plants, Dmg was higher for leaves than for roots. Lack of SdGAME25 expression in U-chemotype leaves, while readily expressed in roots and stems, suggests a pivotal role for SdGAME25 in differentiation of leaf chemotypes in vegetative and flowering plants. By acting as an ontogeny-dependent chemotypic switch, differential regulation of SdGAME25 enables adaptive allocation of SGs, thereby increasing SG chemodiversity in leaves. This indicates that differential expression and/or regulation of glycoalkaloid metabolism genes, rather than their presence or absence, explains observed chemotypic variation in SG chemodiversity among organs and across ontogeny.

Is there any association between blood glycoalkaloid levels and anencephaly in human?

AIM: In various experimental animal studies, it has been proven that solanine, a subtype of glycoalkaloids, is responsible for neural tube defects. However, there have not been any human studies yet in this area. Our aim is to investigate whether there are any connections between blood glycoalkaloid levels and anencephaly in humans. METHODS: Blood and amniotic fluid samples were taken from patients diagnosed with fetal anencephaly during pregnancy. The samples from patients with normal pregnancies were taken as well and was compared to the patients with fetal anencephaly during pregnancy. We searched the levels of three glycoalkaloids: solanine, chaconine and solamargine in the collected samples. RESULTS: Solanine, which is one of the glycoalkaloids, could not be detected in both serum and amniotic fluid in the anencephaly as well as the control groups. However, alpha-solamargine levels were observed to be significantly higher in the blood and amniotic fluid samples of the control group than in the study group (p = 0.04). Alpha-chaconine levels were also significantly higher in the control group (p < 0.001) as well. CONCLUSION: Based on our tests, we can conclude that no connections were found between blood solanine levels and anencephaly during pregnancy. Alpha-chaconine and alpha-solamargine levels were observed to be higher in blood and amniotic fluid in pregnancies without anencephaly. The relationship between glycoalkaloids and congenital anomalies needs to be further investigated in tissues other than blood.

Potato Berries as a Valuable Source of Compounds Potentially Applicable in Crop Protection and Pharmaceutical Sectors: A Review.

Potato (Solanum tuberosum) is a major agricultural crop cultivated worldwide. To meet market demand, breeding programs focus on enhancing important agricultural traits such as disease resistance and improvement of tuber palatability. However, while potato tubers get a lot of attention from research, potato berries are mostly overlooked due to their level of toxicity and lack of usefulness for the food production sector. Generally, they remain unused in the production fields after harvesting the tuber. These berries are toxic due to high levels of glycoalkaloids, which might confer some interesting bioactivities. Berries of various solanaceous species contain bioactive secondary metabolites, suggesting that potato berries might contain similarly valuable metabolites. Therefore, possible applications of potato berries, e.g., in the protection of plants against pests and pathogens, as well as the medical exploitation of their anti-inflammatory, anticarcinogenic, and antifungal properties, are plausible. The presence of valuable compounds in potato berries could also contribute to the bioeconomy by providing a novel use for otherwise discarded agricultural side streams. Here we review the potential use of these berries for the extraction of compounds that can be exploited to produce pharmaceuticals and plant protection products.

A new method for quantification of tomatine-enriched extracts.

BACKGROUND: Green tomato extracts, an agro-food industry waste, are rich in the glycoalkaloid tomatine, which presents activity against several diseases. High-performance liquid chromatography (HPLC) with ultraviolet (UV) detection is one of the most used techniques for quantification of bioactive compounds. The aim of this study was to optimize and validate a selective HPLC method with diode array detector (DAD) for the quantitative analysis of tomatine extracted from green tomatoes by subcritical water. RESULTS: Chromatographic runs were performed on a InertSustain Phenyl (250 mm × 4.6 mm, 5 µm) analytical column, at a wavelength of 205 nm. A concentration range of 50-580 µg mL-1 was used. The validation process was performed considering the linearity, precision, trueness, limit of detection (LOD) and limit of quantitation (LOQ) of the method. The selected mobile phase composed of acetonitrile and a solution of 20 mmol L-1 potassium dihydrogen phosphate (KH2PO4) pH 3, resulted in suitable retention times and a standard calibration curve with adequate linearity (R2 = 0.9999). The method trueness was evaluated by the recovery assay, obtaining a mean recovery of 105% and the precisions were 1.4% and 0.9% (percentage relative standard deviation, RSD%) for the tomatine standard and extract samples, respectively. The inter-day variability was 2.7-9.0% (RSD%) for the standards and 6.9% (RSD%) for extract. The LOD and the LOQ of the method were determined at 8.0 and 24.1 µg mL-1, respectively. CONCLUSION: The herein described method was successfully used for the quantification of tomatine in a tomato-derived extract. Furthermore, the method constitutes a simple and rapid analytical approach able to be used as a routine protocol. © 2024 Society of Chemical Industry.

ELONGATED HYPOCOTYL 5 regulates steroidal glycoalkaloid biosynthesis and fungal tolerance in tomato.

Tomato (Solanum lycopersicum L.) is rich in nutrients and has been an important target for enhancing the accumulation of various metabolites. Tomato also contains cholesterol-derived molecules, steroidal glycoalkaloids (SGAs), which contribute to pathogen defence but are toxic to humans and considered anti-nutritional compounds. Previous studies suggest the role of various transcription factors in SGA biosynthesis; however, the role of light and associated regulatory factors has not been studied in tomato. Here, we demonstrated that SGA biosynthesis is regulated by light through the ELONGATED HYPOCOTYL 5 homolog, SlHY5, by binding to light-responsive G-boxes present in the promoters of structural and regulatory genes. SlHY5 complemented Arabidopsis (Arabidopsis thaliana) and tobacco (Nicotiana tabacum) hy5 mutants at molecular, morphological, and biochemical levels. CRISPR/Cas9-based knockout tomato plants, SlHY5CR, showed down-regulation of SGA and phenylpropanoid pathway genes, leading to a significant reduction in SGA (α-tomatine and dehydrotomatine) and flavonol contents, whereas plants overexpressing SlHY5 (SlHY5OX) showed the opposite effect. Enhanced SGA and flavonol levels in SlHY5OX lines provided tolerance against Alternaria solani fungus, while SlHY5CR lines were susceptible to the pathogen. This study advances our understanding of the HY5-dependent light-regulated biosynthesis of SGAs and flavonoids and their role in biotic stress in tomatoes.

Evaluation of in vivo and in vitro efficacy of solasonine/solamargine-loaded lipid-polymer hybrid nanoparticles against bladder cancer.

Solasonine (SS) and solamargine (SM) are alkaloids known for their antioxidant and anticancer properties, which can be further enhanced by encapsulating them in nanoparticles. This led to a study on the potential therapeutic benefits of SS and SM against bladder cancer when encapsulated in lipid-polymer hybrid nanoparticles (LPHNP). The LPHNP loaded with SS/SM were prepared using the emulsion and sonication method and their physical-chemical properties characterized. The biological effects of these nanoparticles were then tested in both 2D and 3D bladder cancer cell culture models, as well as in a syngeneic orthotopic mouse model based on the MB49 cell line and ethanol epithelial injury. The LPHNP-SS/SM had an average size of 130 nm, a polydispersity index of 0.22 and a positive zeta potential, indicating the presence of chitosan coating on the nanoparticle surface. The dispersion of LPHNP-SS/SM was found to be monodispersed with a span index of 0.539, as measured by nanoparticle tracking analysis (NTA). The recrystallization index, calculated from DSC data, was higher for the LPHNP-SS/SM compared to LPHNPs alone, confirming the presence of alkaloids within the lipid matrix. The encapsulation efficiency (EE%) was also high, with 91.08 % for SS and 88.35 % for SM. Morphological analysis by AFM and Cryo-TEM revealed that the nanoparticles had a spherical shape and core-shell structure. The study showed that the LPHNP-SS/SM exhibited mucoadhesive properties by physically interacting with mucin, suggesting a potential improvement in interaction with mucous membrane. Both the free and nanoencapsulated SS/SM demonstrated dose-dependent cytotoxicity against bladder cancer cell lines after 24 and 72 h of treatment. In 3D bladder cell culture, the nanoencapsulated SS/SM showed an IC50 two-fold lower than free SS/SM. In vivo studies, the LPHNP-SS/SM displayed an antitumoral effect at high doses, leading to a significant reduction in bladder volume compared to the positive control. However, there were observed instances of systemic toxicity and liver damage, indicated by elevated levels of transaminases (TGO and TGP). Overall, these results indicate that the LPHNPs effectively encapsulated SS/SM, showing high encapsulation efficiency and stability, along with promising in vitro and in vivo antitumoral effects against bladder cancer. Further evaluation of its systemic toxicity effects is necessary to ensure its safety and efficacy for potential clinical application.

Enhancement of production of glycoalkaloids by elicitors along with characterization of gene expression of pathways in Solanum xanthocarpum.

Solanum xanthocarpum fruits are used in the treatment of cough, fever, and heart disorders. It possesses antipyretic, hypotensive, antiasthmatic, aphrodisiac and antianaphylactic properties. In the present study, 24 elicitors (both biotic and abiotic) were used to enhance the production of glycoalkaloids in cell cultures of S. xanthocarpum. Four concentrations of elicitors were added into the MS culture medium. The maximum accumulation (5.56-fold higher than control) of demissidine was induced by sodium nitroprusside at 50 mM concentration whereas the highest growth of cell biomass (4.51-fold higher than control) stimulated by systemin at 30 mM concentration. A total of 17 genes of biosynthetic pathways of glycoalkaloids were characterized from the cells of S. xanthocarpum. The greater accumulation of demissidine was confirmed with the expression analysis of 11 key biosynthetic pathway enzymes e.g., acetoacetic-CoA thiolase, 3- hydroxy 3-methyl glutaryl synthase, ß-hydroxy ß-methylglutaryl CoA reductase, mevalonate kinase, farnesyl diphosphate synthase, squalene synthase, squalene epoxidase, squalene-2,3- epoxide cyclase, cycloartenol synthase, UDP-glucose: solanidine glucosyltransferase and UDP-rhamnose: solanidine rhamno-galactosyl transferase. The maximum expression levels of UDP-rhamnose: solanidine rhamno-galactosyl transferase gene was recorded in this study.

Assessment of the Content of Glycoalkaloids in Potato Snacks Made from Colored Potatoes, Resulting from the Action of Organic Acids and Thermal Processing.

Glycoalkaloids (TGAs, total glycoalkaloids), toxic secondary metabolites, are found in potatoes (110-335 mg·kg-1 DW), mainly in the peel. Colorful, unpeeled potatoes are an innovative raw material for the production of snacks which are poorly tested in terms of their glycoalkaloid content. Third-generation snacks and French fries made from red-fleshed Mulberry Beauty (MB) and purple-fleshed Double Fun (DF) potatoes were produced with the use of 1% solutions of ascorbic, citric, lactic, malic, and tartaric acids to stabilize the structure of anthocyanins in the raw material and maintain their color in obtained products. The influence of the type of acid and thermal processes, like frying, microwaving, and baking, on the content of glycoalkaloids in ready-made products was examined. Only 0.45-1.26 mg·100 g-1 of TGA was found in pellet snacks and 1.32-1.71 mg·100 g-1 in French fries. Soaking blanched potatoes in organic acid solution reduced the α-chaconine content by 91-97% in snacks and by 57-93% in French fries in relation to the raw material to the greatest extent after the use of malic acid and the DF variety. The effect of lactic and citric acid was also beneficial, especially in the production of baked French fries from MB potatoes.

Steroidal scaffold decorations in Solanum alkaloid biosynthesis.

Steroidal glycoalkaloids (SGAs) are specialized metabolites produced by hundreds of Solanum species, including important vegetable crops such as tomato, potato, and eggplant. Although it has been known that SGAs play important roles in defense in plants and "anti-nutritional" effects (e.g., toxicity and bitterness) to humans, many of these molecules have documented anti-cancer, anti-microbial, anti-inflammatory, anti-viral, and anti-pyretic activities. Among these, α-solasonine and α-solamargine isolated from black nightshade (Solanum nigrum) are reported to have potent anti-tumor, anti-proliferative, and anti-inflammatory activities. Notably, α-solasonine and α-solamargine, along with the core steroidal aglycone solasodine, are the most widespread SGAs produced among the Solanum plants. However, it is still unknown how plants synthesize these bioactive steroidal molecules. Through comparative metabolomic-transcriptome-guided approach, biosynthetic logic, combinatorial expression in Nicotiana benthamiana, and functional recombinant enzyme assays, here we report the discovery of 12 enzymes from S. nigrum that converts the starting cholesterol precursor to solasodine aglycone, and the downstream α-solasonine, α-solamargine, and malonyl-solamargine SGA products. We further identified six enzymes from cultivated eggplant that catalyze the production of α-solasonine, α-solamargine, and malonyl-solamargine SGAs from solasodine aglycone via glycosylation and atypical malonylation decorations. Our work provides the gene tool box and platform for engineering the production of high-value, steroidal bioactive molecules in heterologous hosts using synthetic biology.

A comprehensive approach to the monitoring of steroidal glycoalkaloids in foods of plant origin.

Steroidal glycoalkaloids (GAs) are toxins produced by solanaceous plants. As there are no fully standardized methods for their extraction and determination in food, the research aimed to: (1) develop and critically compare methods based on gas (GC) and liquid (LC) chromatography, including their coupling with mass spectrometry, and (2) to develop and optimize a universal GA extraction method. Hyphenated techniques proved to be the most useful in GA analysis: LC-MS was the most sensitive one, while GC-MS offered the highest chromatographic resolution. It was proven that quantitative results obtained using different analytical techniques cannot be directly compared. New extraction method that is more efficient than the AOAC method (997.13) was then designed and optimized. It was characterized by higher absolute recovery (99% and 34%, respectively) and allowed to extract much more GAs from the same material (e.g. 21.2 ± 1.4 and 11.82 ± 0.97 mg g-1 of potato tubers, respectively).

Health Benefits of the Alkaloids from Lobeira (Solanum lycocarpum St. Hill): A Comprehensive Review.

Solanum is the largest genus within the Solanaceae family and has garnered considerable attention in chemical and biological investigations over the past 30 years. In this context, lobeira or "fruta-do-lobo" (Solanum lycocarpum St. Hill), a species predominantly found in the Brazilian Cerrado, stands out. Beyond the interesting nutritional composition of the fruits, various parts of the lobeira plant have been used in folk medicine as hypoglycemic, sedative, diuretic, antiepileptic, and antispasmodic agents. These health-beneficial effects have been correlated with various bioactive compounds found in the plant, particularly alkaloids. In this review, we summarize the alkaloid composition of the lobeira plant and its biological activities that have been reported in the scientific literature in the last decades. The compiled data showed that lobeira plants and fruits contain a wide range of alkaloids, with steroidal glycoalkaloid solamargine and solasonine being the major ones. These alkaloids, but not limited to them, contribute to different biological activities verified in alkaloid-rich extracts/fractions from the lobeira, including antioxidant, anti-inflammatory, anticancer, antigenotoxic, antidiabetic, antinociceptive, and antiparasitic effects. Despite the encouraging results, additional research, especially toxicological, pre-clinical, and clinical trials, is essential to validate these human health benefits and ensure consumers' safety and well-being.

Structural Impact of Steroidal Glycoalkaloids: Barrier Integrity, Permeability, Metabolism, and Uptake in Intestinal Cells.

SCOPE: Potato tubers represent an essential food component all over the world and an important supplier of carbohydrates, fiber, and valuable proteins. However, besides their health promoting effects, potatoes contain α-solanine and α-chaconine, which are toxic steroidal glycoalkaloids (SGAs). Other solanaceous plants like eggplants and tomatoes produce SGAs as well, different in their chemical structure. This study aims to investigate toxic effects (cholinesterase inhibition, membrane, and barrier disruption), permeability, metabolism, and structure-activity relationships of SGAs. METHODS AND RESULTS: α-solanine, α-chaconine, α-solasonine, α-solamargine, α-tomatine, and their respective aglycones solanidine, solasodine, and tomatidine are analyzed using Ellman assay, cellular impedance spectroscopy, cell extraction, and Caco-2 intestinal model. Additionally, metabolism is analyzed by HPLC-MS techniques. The study observes dependencies of barrier disrupting potential and cellular uptake on the carbohydrate moiety of SGAs, while permeability and acetylcholinesterase (AChE) inhibition are dominated by the steroid backbone. SGAs show low permeabilities across Caco-2 monolayers in subtoxic concentrations. In contrast, their respective aglycones reveal higher permeabilities, but are extensively metabolized. CONCLUSION: Besides structure-activity relationships, this study provides new information on the overall effects of steroidal alkaloids on intestinal cells and closes a gap of knowledge for the metabolic pathway from oral uptake to final excretion.

Agri-Food Waste Recycling for Healthy Remedies: Biomedical Potential of Nutraceuticals from Unripe Tomatoes (Solanum lycopersicum L.).

Unripe tomatoes represent an agri-food waste resulting from industrial by-processing products of tomatoes, yielding products with a high content of bioactive compounds with potential nutraceutical properties. The food-matrix biological properties are attributed to the high steroidal glycoalkaloid (SGA) content. Among them, α-tomatine is the main SGA reported in unripe green tomatoes. This review provides an overview of the main chemical and pharmacological features of α-tomatine and green tomato extracts. The extraction processes and methods employed in SGA identification and the quantification are discussed. Special attention was given to the methods used in α-tomatine qualitative and quantitative analyses, including the extraction procedures and the clean-up methods applied in the analysis of Solanum lycopersicum L. extracts. Finally, the health-beneficial properties and the pharmacokinetics and toxicological aspects of SGAs and α-tomatine-containing extracts are considered in depth. In particular, the relevant results of the main in vivo and in vitro studies reporting the therapeutic properties and the mechanisms of action were described in detail.

Integrated gene-free potato genome editing using transient transcription activator-like effector nucleases and regeneration-promoting gene expression by Agrobacterium infection.

Genome editing is highly useful for crop improvement. The method of expressing genome-editing enzymes using a transient expression system in Agrobacterium, called agrobacterial mutagenesis, is a shortcut used in genome-editing technology to improve elite varieties of vegetatively propagated crops, including potato. However, with this method, edited individuals cannot be selected. The transient expression of regeneration-promoting genes can result in shoot regeneration from plantlets, while the constitutive expression of most regeneration-promoting genes does not result in normally regenerated shoots. Here, we report that we could obtain genome-edited potatoes by positive selection. These regenerated shoots were obtained via a method that combined a regeneration-promoting gene with the transient expression of a genome-editing enzyme gene. Moreover, we confirmed that the genome-edited potatoes obtained using this method did not contain the sequence of the binary vector used in Agrobacterium. Our data have been submitted to the Japanese regulatory authority, the Ministry of Education, Culture, Sports, Science and Technology (MEXT), and we are in the process of conducting field tests for further research on these potatoes. Our work presents a powerful method for regarding regeneration and acquisition of genome-edited crops through transient expression of regeneration-promoting gene.

Downregulation of a cluster of genes encoding nitrate transporter 1/peptide transporter family proteins in tomato with a mutated JRE4 transcription factor.

A group of anti-nutritional specialized metabolites called steroidal glycoalkaloids (SGAs) are produced in Solanum species such as tomato, potato, and eggplant. The transcription factor JASMONATE-RESPONSIVE ETHYLENE RESPONSE FACTOR 4 (JRE4) regulates many SGA biosynthesis genes in tomato and potato. Here we report that the expression of a cluster of genes encoding nitrate transporter 1/peptide transporter family (NPF) members is downregulated in the jre4-1 loss-of-function tomato mutant, which has a low-SGA phenotype compared to the wild type. NPFs are a large family of plant membrane transporters that transport a wide range of substrates, including specialized metabolites. We found that the JRE4-regulated NPF genes are induced by the defense-related phytohormone jasmonate. Conversely, jasmonate-mediated induction of gene expression was attenuated by ethylene treatment of the leaves. The co-regulation of the NPF genes with SGA biosynthesis genes by JRE4 suggests that NPF transporters are involved in the SGA pathway.

Extracción de glicoalcaloides de papa nativa (Solanumphureja) variedad ratona morada con líquidos presurizados / Extraction of glycoalkaloids of native potato (Solanum phureja) ratona morada variety with pressurized liquids

RESUMEN La cáscara de papa es un residuo originado por su procesamiento agroindustrial, que genera un gran impacto ambiental debido a su inadecuado manejo o eliminación. No obstante, la cáscara de papa es una buena fuente de ingredientes funcionales como los glicoalcaloides (GA). Este estudio investigó la extracción de dos GA (α-solanina y α-chaconina) de cáscara de papa nativa (Solanum phureja) variedad ratona morada del departamento de Nariño-Colombia, utilizando la tecnología de extracción con líquidos presurizados (ELP), mediante un diseño experimental central compuesto, con el fin de determinar el efecto de la presión (P) y la temperatura (T), sobre el rendimiento y la composición de GA. Los extractos se analizaron por cromatografía líquida HPLC. Los resultados obtenidos permitieron establecer que la temperatura ejerció un efecto significativo (p <0,05) sobre el rendimiento, α-solanina y α-chaconina. El rendimiento óptimo fue de 5,62 % p/p. Los GA, α-solanina y α-chaconina, aumentaron su concentración al disminuir la temperatura. La extracción con líquidos presu-rizados promete ser una buena alternativa al uso de solventes orgánicos para obtener compuestos bioactivos de cáscara de papa.

SUMMARY Potato peel is a waste originated by its agro-industrial processing, generating an environmental impact due to its inadequate handling or elimination. However, potato peel is a good source of functional ingredients such as glycoalkaloids (GA). This study investigated the extraction of two GA (α-solanine and α-chaconine) from native potato rind (Solanum phureja) ratona morada variety from the department of Nariño-Colombia, using the technology of extraction with pressurized liquids (PLE), through a experimental central composite design, in order to determine the effect of pressure (P) and temperature (T), on the performance and composition of GA. The extracts were analyzed by liquid chromatography HPLC. The results obtained allowed us to establish that the temperature exerted a significant effect (p <0.05) on the yield, α-solanine and α-chaconine. For the yield an optimum value of 5.62 % w/w was reached. α-solanine and α-chaconine increased their concentration as the temperature decreased. The extraction with pressurized liquids promises to be a good alternative in the use of organic solvents to obtain bioactive compounds of potato husk.

In vitro activities of glycoalkaloids from the Solanum lycocarpum against Leishmania infantum

ABSTRACT Leishmania infantum is an etiologic agent of visceral leishmaniasis. This disease is a neglected disease that can be fatal if not treated and additionally, the few therapeutic option present several drawbacks, including difficult route of administration and toxicity, which turn the search for new therapeutic alternatives necessary. Herein, we evaluated the leishmanicidal in vitro activity of the solanum extract from Solanum lycocarpum A. St.-Hil., Solanaceae, and the isolated alkaloids solasodine, solamargine and solasonine against promastigotes and intracellular amastigotes of L. infantum. Solasodine (IC50-pro = 4.7 µg/ml; IC50-ama = 10.8 µg/ml) and solamargine (IC50-pro = 8.1 µg/ml; IC50-ama = 3.0 µg/ml) exhibited interesting leishmanicidal ativity. Solasonine was approximately four-times (Selective Index 3.7) more selective to the parasite than to the host cells. This data suggest that solasonine might be considered as a potential drug candidate for leishmaniasis treatment.

Ecofriendly Synthesis of Silver Nanoparticles Using Potato Steroidal Alkaloids and Their Activity Against Phytopathogenic Fungi

ABSTRACT In order to reduce the excessive reliance on the toxic chemical fungicides, the present study aimed to isolate the total potato glycoalkaloids (TPAs), and the two steroidal alkaloids α-chaconine and α-solanine from potatoes, Solanum tuberosum L. Their structures were characterized using physical and spectroscopic methods including (UV, IR, 1H, 13C--NMR, 2D 1H-1H COSY, HMBC and NOESY). Silver nanoparticles (AgNPs) were prepared from potato alkaloids through a green synthesis approach. Potato alkaloids and their nanoparticles inhibited mycelial growth of the phytopathogenic fungi Alternaria alternate, Rhizoctonia solani, Botrytis cinerea and Fusarium oxysporum f. sp. lycopersici with low minimal inhibitory and minimal fungicidal concentrations. R. solani was the most susceptible, while F. oxysporum was the most resistant. TPAs was the most fungitoxic (EC50's were 19.8, 22.5, 26.5 and 32.3 µg/ml against R. solani, A. alternate, B. cinerea and F. oxysporum respectively). A mixture of α-solanine and α-chaconine (1:1) showed a marked antifungal activity. AgNPs (size 39.5-80.3 diameter) from alkaloids showed improved fungitoxic activity (EC50's of TPAs nanoparticles ranged between 10.9 and 16.1 µg/ml). Alkaloids exhibited no or a slight phytotoxicity against wheat and radish. Results recommend the potential of using potato alkaloids and their nanoparticles as biorational alternatives to conventional fungicides.