Search Results (36)

The present study was conducted to evaluate the effect of biodegradable mulches and microbial biostimulants (BMs) on processing tomato (Solanum lycopersicum L.) cv. Pietra rossa. A black Mater-Bi^®-based film (MB), a black paper film (Np), a light-brown paper film (Sp), and bare soil (BS) were factorially combined with Trichoderma harzianum M10, T. afroharzianum T22, and the metabolite 6-pentyl-α-pyrone (6PP). The mulching practice influenced soil temperatures that were lower under all types of mulching from the end of May up to the first week of June, but, by contrast, they were greater than those of the BS just under MB for the entire next period. Mulching and BM application increased the marketable fruits (by 26% MB vs. BS and by 27% T22 vs. untreated control (CTRL)) and reduced rotten fruits (by 46% Np vs. BS and by 31% T22 vs. CTRL). Lycopene increased under MB and Sp (not Np) vs. BS and with 6PP and T22 (not M10) vs. CTRL, while ascorbic acid was unaffected by mulching and increased only with T22, and total phenols decreased with mulching but were unaffected by BMs. Tomato berry metabolism is treatment-dependent: 6PP consistently separated from the microbial-based treatments (M10 and T22) across all mulching types. Overall, it demonstrated a consistent and distinct impact on a subset of metabolites (i.e., phenolic acids and steroidal glycoalkaloids) across different mulching conditions compared to the microbial treatments, which exhibited a mulch-dependent accumulation. Full article

Steroidal glycoalkaloids (GAs) are key plant defense compounds, yet their effects on insect gut physiology are not fully understood. We investigated how purified α-chaconine and Solanum tuberosum leaf extract influence the gut function and growth of the mealworm Tenebrio molitor. Larvae were exposed to sublethal doses of GAs, and gut contractility, midgut digestive enzyme activity and body weight were analysed over time. Both α-chaconine and potato extract caused a rapid decrease in digestive enzyme activity 2 h after exposure, followed by a clear increase above control levels after 24 h, indicating a time-dependent compensatory response of the digestive system. Gut contractility was significantly enhanced in treated larvae, and larvae exposed to both treatments exhibited a body weight loss over 72 h. These results show that potato glycoalkaloids strongly modulate the gut physiology of T. molitor while allowing continued growth, highlighting both the plasticity of insect digestive responses and the need to consider sublethal, gut-centered effects when evaluating glycoalkaloids as candidates for bioinsecticidal agents. Full article

Light exposure can induce post-harvest potato tubers to become green due to the accumulation of chlorophyll (Chl) and the formation of glycoside alkaloids, posing a potential risk to food safety. This study evaluated exogenous indole-3-acetic acid (IAA) to inhibit greening in Solanum tuberosum cv. Tongshu 31. IAA treatment maintained a relatively high a* value and significantly reduced both Chl content and the accumulation of toxic steroidal glycoalkaloids (SGAs), such as α-solanine and α-chaconine. In addition, IAA treatment also delayed the decrease in hardness and weight loss of tubers during storage, and helped maintain a high content of starch and reduce sugar. Transcriptome analysis revealed that IAA downregulated HEMA1, CHLH, and GUN4, among other key genes in the Chll biosynthesis pathway, thereby inhibiting Chl accumulation. IAA also modulated hormone networks, increasing gibberellin (GA) and jasmonic acid (JA), decreasing abscisic acid (ABA), and activating signaling genes (StGID1, StJAR1, StPYR1, StPYL4), enhancing tuber defense. These results indicate that IAA can inhibit the synthesis of Chl by regulating gene expression. This study provides a new strategy for alleviating the greening problem of potatoes and explains the potential mechanism by which IAA inhibits Chl synthesis in potato tubers. Full article

Cherry tomato is a notable dietary source of metabolites associated with antioxidant functions. However, how ripening reshapes primary, specialized, and volatile metabolites remains incompletely resolved. Green-ripe and red-ripe fruits were comparatively analyzed using targeted HPLC assays for quality indices and vitamins, UPLC–MS/MS for non-volatile metabolites, and HS-SPME–GC–MS for volatiles. Ripening was accompanied by a pronounced accumulation of lycopene and an increase in soluble solids, reflecting a shift of sugars toward glucose and fructose while sucrose remained low. Organic acids declined overall, with citric acid remaining predominant. The free-amino-acid pool expanded, with redistribution from GABA toward glutamate and aspartate. Vitamins exhibited stage-dependent patterns; antioxidant-related vitamins (A, E, and C) were higher at the red-ripe stage, indicating a compositional enhancement relevant to nutritional quality. Non-volatile metabolomics revealed 618 differentially accumulated metabolites, with phenolic acids, flavonoids, alkaloids, amino acids, and lipids as major classes. Phenolic acids and flavonols, dominated by hydroxycinnamoyl-quinic acids and quercetin/kaempferol glycosides, accumulated at the red-ripe stage, whereas steroidal glycoalkaloids decreased, suggesting conversion away from bitter or anti-nutritional constituents. GC–MS profiling identified 788 volatiles, with esters, terpenoids, and ketones contributing more than half of the volatilome. Ripening favored fruity–floral odorants such as β-ionone and (5Z)-octa-1,5-dien-3-one, while reducing green-leaf aldehydes. These stage-specific shifts in metabolite composition jointly define the sensory and nutritional maturation of cherry tomato. The identified metabolite markers provide a foundation for evaluating fruit maturity and guiding breeding toward improved quality attributes. Full article

Potato tubers undergo greening and accumulate steroidal glycoalkaloids (SGAs) upon light exposure, posing potential food safety risks. In this study, six potato cultivars (“Favorita”, “Lucinda”, “Jizhangshu 12”, “Longshu 10”, “Qingshu 9”, and “Purple Potato”) were subjected to six light treatments (dark, UVA, blue, green, red, and white), and peel color, pigment content, SGAs, and the expression of genes related to light signaling, chlorophyll biosynthesis, and SGA biosynthesis was evaluated. Under green light, the contents of α-solanine and α-chaconine were 76.22 and 171.84 mg/kg fresh weight (FW), respectively; by contrast, their levels under blue and white light were approximately 60% higher. These effects may be mediated by the upregulation of HY5 and COP1 expression, which in turn could regulate the biosynthesis of chlorophyll-related genes (CHID, CHLI1) and SGA-related genes (HMGR, SGT1). Yellow-skinned cultivars exhibited pronounced light sensitivity (chlorophyll 18.47–18.52 mg/kg FW; SGAs up to 290.41 mg/kg FW), whereas red- and purple-skinned cultivars delayed greening through anthocyanin-mediated light attenuation. Collectively, these findings provide a framework for postharvest management and breeding, suggesting that reducing blue light while enhancing green light in spectral illumination, together with the development of anthocyanin-enriched cultivars, may serve as effective strategies to extend shelf life, mitigate food safety risks, and reduce postharvest losses. Full article

Background: Lung cancer is a prevalent malignancy globally, with non-small cell lung cancer (NSCLC) accounting for 80–85% of cases. Solalyraine A1 (SA1) is a steroidal glycoalkaloid derived from Solanum lyratum. However, the effect and mechanism of SA1 on NSCLC remain unclear. Methods: The exosomes from SA1-treated A549 cells were prepared and administered to A549 xenograft mice. Proteomics analysis of SA1-treated A549 cells and their exosomes was conducted to assess the mechanism. Bioinformatics analysis was utilized to identify differentially expressed proteins (DEPs) and key signaling pathways. Western blot analysis confirmed the expression of potential targets. Results: SA1 effectively suppressed tumor growth in A549 xenografts, demonstrating a remarkable inhibition rate of 70.48%. A total of 1154 DEPs were identified in A549 cells, primarily associated with the ribosome pathway. Additionally, 746 DEPs were identified in exosomes, mainly involved in the spliceosome pathway. Five highly regulated DEPs were selected for verification. SA1 was found to suppress MUC5B and elevate APOB expression in A549 cells, while inhibiting MFGM, ANGL4 and increasing GCN1 expression in exosomes. Conclusions: This study demonstrates that SA1 exhibits anti-NSCLC effects by regulating exosome function and related protein expression, providing novel insights for NSCLC treatment. Full article

The potato (Solanum tuberosum L.) ranks among the most consumed agricultural products globally and is nutrient-rich. Exposure of potato tubers’ epidermal and subcutaneous tissues to light results in greening and the production of neurotoxic steroidal glycoalkaloids, which significantly reduces tuber quality, increases food safety risks, and leads to rejection by consumers and the processing industry. This review conducts an in-depth analysis of three key aspects: (1) the differences in various light conditions, namely, the disparities in light sources, wavelengths, intensities, and durations; (2) the characteristics of potato cultivars resistant to greening; and (3) the molecular mechanisms of light-induced biosynthesis of chlorophyll and steroidal glycoalkaloids (SGAs). This review is expected to provide technical support for potato food safety measures and a theoretical foundation for the molecular breeding of green-resistant potato varieties. Full article

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. Full article

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. Full article

Potato is susceptible to light exposure and wounding during harvesting and transportation. However, the metabolite profile changes in these potato tubers are unclear. The potato cultivars in this study included Hezuo88 (HZ88), Shida6 (SD6), and Jianchuanhong (JCH); the effects of light exposure (L), wounding (W), and the cooking process on potato metabolites were determined. In total, 973 metabolites were identified, with differential metabolites (mainly alkaloids, flavonoids, and phenolic acids) accumulated on days 0 and 2 (0 d and 2 d) in the 0dHZ88 vs. 0dJCH (189), 0dHZ88 vs. 0dSD6 (147), 0dSD6 vs. 0dJCH (91), 0dJCH vs. 2dIJCH (151), 0dJCH vs. 2dWDJCH (250), 0dJCH vs. 2dWLJCH (255), 2dIJCH vs. 2dWDJCH (234), and 2dIJCH vs. 2dWLJCH (292) groups. The flavonoid content in the light exposure group was higher than that in the dark group. The alkaloid content in the wounded group was higher than that in the uninjured potato tuber group, but the lipid content in the wounded group was lower. Importantly, only 5.54% of the metabolites changed after potato tuber steaming. These results provide valuable information for the breeding and consumption of potato tubers. Full article

Tomato by-products represent a good source of phytochemical compounds with health properties, such as the steroidal glycoalkaloid α-tomatine (α-TM) and its aglycone tomatidine (TD). Both molecules have numerous beneficial properties, such as potential anticancer activity. Unfortunately, their therapeutic application is limited due to stability and bioavailability issues. Therefore, a valid strategy seems to be their encapsulation into Solid Lipid Nanoparticles (SLN). The nanoformulations containing α-TM (α-TM-SLN) and TD (TD-SLN) were prepared by solvent-diffusion technique and subsequently characterized in terms of technological parameters (particle size, polydispersity index, zeta potential, microscopy, and calorimetric studies). To assess the effect of α-TM and TD on the percentage of cellular viability in Olfactory Ensheathing Cells (OECs), a peculiar glial cell type of the olfactory system used as normal cells, and in SH-SY5Y, a neuroblastoma cancer cell line, an MTT test was performed. In addition, the effects of empty, α-TM-SLN, and TD-SLN were tested. Our results show that the treatment of OECs with blank-SLN, free α-TM (0.25 µg/mL), and TD (0.50 µg/mL) did not induce any significant change in the percentage of cell viability when compared with the control. In contrast, in SH-SY5Y-treated cells, a significant decrease in the percentage of cell viability when compared with the control was found. In particular, the effect appeared more evident when SH-SY5Y cells were exposed to α-TM-SLN and TD-SLN. No significant effect in blank-SLN-treated SH-SY5T cells was observed. Therefore, SLN is a promising approach for the delivery of α-TM and TD. Full article

Steroid glycoalkaloids (SGAs) are a class of cholesterol-derived metabolites commonly found in the Solanaceae plants. α-Tomatine, a well-known bitter-tasting compound, is the major SGA in tomato, accumulating extensively in all plant tissues, particularly in the leaves and immature green fruits. α-Tomatine exhibits diverse biological activities that contribute to plant defense against pathogens and herbivores, as well as conferring certain medicinal benefits for human health. This review summarizes the current knowledge on α-tomatine, including its molecular chemical structure, physical and chemical properties, biosynthetic and metabolic pathways, and transcriptional regulatory mechanisms. Moreover, potential future research directions and applications of α-tomatine are also discussed. Full article

Steroidal glycoalkaloids (SGAs) are secondary metabolites that are closely associated with the sensory and processing qualities of potato tubers. GGE biplots are a widely used tool for analyzing crop breeding analysis. This study aimed to investigate the effect of light on SGA biosynthesis by employing GGE biplots to analyze the transcriptional gene expression of seven genes involved in the SGA biosynthesis pathway. Tubers of five different potato genotypes were incubated for 6, 12, and 24 h under red light. The expression levels of the seven genes were measured using qRT-PCR for analysis. Further analysis of the data was performed using GGE biplots. Our results indicated significantly higher expression levels for Pvs1, Sgt1, and Sgt3 genes than those of the remaining tested genes. Across the three red light illumination durations, Sgt3 showed high and stable expression, although it showed less stability across the different genotypes. Interestingly, the expression patterns of the seven genes were extremely similar for the 12 h and 24 h treatments. It was found that at least 6 h of red light illumination was required for optimal gene expression in all five genotypes, particularly in the genotype Zhuangshu-3 (DXY) after 24 h of treatment. Additionally, significant expression of the seven genes was observed in the L-6 genotype after 12 and 6 h of red light illumination. These results highlight that GGE biplots are an appropriate tool for analyzing and illustrating the differential expression profiles of the seven key genes involved in SGA biosynthesis in potato tubers. This study provides valuable insights into the biosynthesis and metabolism of SGAs in potatoes. Moreover, it demonstrates the potential application of GGE biplots in crop breeding and other research fields. Full article

The accumulation of chlorophyll and antinutritional glycoalkaloids in potato tubers resulting from exposure to light has been widely recognized as a cause of unpredictable quality loss of potato tuber. While transcriptional regulation of light-induced chlorophyll and glycoalkaloids accumulation has been extensively investigated, the mechanisms of post-transcriptional regulation through miRNA remain largely unexplored. An experimental model, the tubers of Solanum chacoense, were used to identify light-responsive miRNA–target interactions (MTIs) related to tuber greening and glycoalkaloid biosynthesis by employing multi-omics approaches (miRNA-seq and degradome-seq). A total of 732 unique mature miRNAs have been identified in S. chacoense. In total, 6335 unique target transcripts were cleaved by 489 known miRNAs and 153 novel miRNAs. The results revealed that light-responsive miRNAs can be grouped into eight temporally related clusters and play important roles in various physiological processes such as plant growth, stress responses, and primary and secondary metabolism. Multi-omics analyses have revealed that the modulation of transcript abundance of MYB59, HSPs, and EBF1/EBF2 by light-responsive miRNAs is pivotal for their function in cross-tolerance responses to both abiotic and biotic stresses. Furthermore, our findings suggest that many light-responsive miRNAs are crucial regulators in various biosynthetic pathways, including tetrapyrrole biosynthesis, suberin biosynthesis, and steroid biosynthesis. These findings highlight the significant role of light-responsive miRNAs in secondary metabolic pathways, particularly in isoprenoid, terpenoid, and glycoalkaloid biosynthesis, and have implications for the precise manipulation of metabolic pathways to produce new potato varieties with improved resistance to greening and lower glycoalkaloid levels. Full article