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Unlike most plants, members of the genus Solanum produce cholesterol and use this as a precursor for steroidal glycoalkaloids. The production of the compounds begins as a branch from brassinosteroid biosynthesis, which produces cholesterol that is further modified to produce steroidal glycoalkaloids. During the cholesterol biosynthesis pathway, genetic engineering could alter the formation of cholesterol from provitamin D3 (7-dehydrocholesterol) and produce vitamin D3. Cholesterol is a precursor for many steroidal glycoalkaloids, including a-tomatine and esculeoside A. Alpha-tomatine is consumed by mammals and it can reduce cholesterol content and improve LDL:HDL ratio. When there is a high a-tomatine content, the fruit will have a bitter flavor, which together with other steroidal glycoalkaloids serving as protective and defensive compounds for tomato against insect, fungal, and bacterial pests. These compounds also affect the rhizosphere bacteria by recruiting beneficial bacteria. One of the steroidal glycoalkaloids, esculeoside A increases while fruit ripening. This review focuses on recent studies that uncovered key reactions of the production of cholesterol and steroidal glycoalkaloids in tomato connecting to human health, fruit flavor, and plant defense and the potential application for tomato crop improvement. [ABSTRACT FROM AUTHOR]

Abstract Introduction The objective of this study is to investigate the shear bonding strength of a glycoalkaloid, also a novel matrix metalloproteinase enzyme known as α-tomatine, on two different surfaces of dentin (sound & caries-affected) and its efficacy against cariogenic microorganisms using in vitro and in silico methods. Methods The effect of a-tomatine at different concentrations (0.75 / 1 / 1.5 µM) on shear bonding strength in caries-affected and sound dentin was also investigated (n = 10; each per subgroup). The analysis of shear bonding and failure tests was conducted after a 24-hour storage period. Fracture surfaces were examined under a scanning electron microscope. A stock solution 3 mM of a-tomatine was prepared for antimicrobial evaluation. Antimicrobial activities of the agents against Streptococcus mutans ATCC 25175, Lactobacillus casei ATCC 4646, and Candida albicans ATCC 10231 standard strains were investigated by microdilution method. In addition, through the method of molecular docking and dynamic analysis, the affinity of a-tomatine for certain enzymes of these microorganisms was examined. Results The pretreatment agent and dentin type significantly influenced shear bonding strength values (p

This study aims to examine the effect of a-tomatine, a new matrix metalloproteinase inhibitor for dentistry, as a surface pretreatment on the bonding strength of different types of dentine via in vitro and in silico methods. The binding efficacy of both a-tomatine and chlorhexidine to MMP-2, 8, and 9 was evaluated through molecular docking and dynamics analyses. For microtensile testing (µTBS), specimens (n = 84) were categorized into two groups based on the type of dentin: sound (SD) and eroded (ED) (n = 42). Each group was further divided into three subgroups according to the utilization of surface pretreatment agents (1.5 µM of tomatine, 2% chlorhexidine (CHX), and the control). Composite buildups were gradually created via a three-step etch-and-rinse technique. The specimens were sectioned into sticks and subsequently subjected to µTBS after aging for either 24 h (n = 7) or 6 months (n = 7). The data were subjected to analysis using two-way ANOVA with a Bonferroni correction post hoc test. The significance level was evaluated at a minimum of p < 0.05. According to molecular docking and dynamic simulation analyses, a-tomatine exhibits a higher affinity for MMP-2, -8, and -9 enzymes compared to chlorhexidine. Lower µTBS values were observed in all ED groups compared to the SD groups. Following 24-h aging, the CHX application in both the SD and ED groups achieved lower µTBS values compared to the control group (p < 0.01 and p > 0.05, respectively). The most favorable results were consistently achieved across all the subgroups subjected to a-tomatine applications (p < 0.05). a-tomatine is a more effective MMP inhibitor than chlorhexidine in terms of preserving bond strength values over time and its capacity to bind to MMP-2,8, and 9 for inhibition. [ABSTRACT FROM AUTHOR]

This study aims to examine the effect of a-tomatine, a new matrix metalloproteinase inhibitor for dentistry, as a surface pretreatment on the bonding strength of different types of dentine via in vitro and in silico methods. The binding efficacy of both a-tomatine and chlorhexidine to MMP-2, 8, and 9 was evaluated through molecular docking and dynamics analyses. For microtensile testing (µTBS), specimens (n = 84) were categorized into two groups based on the type of dentin: sound (SD) and eroded (ED) (n = 42). Each group was further divided into three subgroups according to the utilization of surface pretreatment agents (1.5 µM of tomatine, 2% chlorhexidine (CHX), and the control). Composite buildups were gradually created via a three-step etch-and-rinse technique. The specimens were sectioned into sticks and subsequently subjected to µTBS after aging for either 24 h (n = 7) or 6 months (n = 7). The data were subjected to analysis using two-way ANOVA with a Bonferroni correction post hoc test. The significance level was evaluated at a minimum of p < 0.05. According to molecular docking and dynamic simulation analyses, a-tomatine exhibits a higher affinity for MMP-2, -8, and -9 enzymes compared to chlorhexidine. Lower µTBS values were observed in all ED groups compared to the SD groups. Following 24-h aging, the CHX application in both the SD and ED groups achieved lower µTBS values compared to the control group (p < 0.01 and p > 0.05, respectively). The most favorable results were consistently achieved across all the subgroups subjected to a-tomatine applications (p < 0.05). a-tomatine is a more effective MMP inhibitor than chlorhexidine in terms of preserving bond strength values over time and its capacity to bind to MMP-2,8, and 9 for inhibition.

Abstract: The ?-tomatine is a glycoalkaloid found in immature tomatoes (Lycopersicon esculetum). Currently, ?-tomatine has shown anticancer effects due to its anti-proliferative property. Stressors are one of the factors contributing to the antiproliferative activity of ?-tomatine that can modify cellular homeostasis. Among the cell stressors are the endoplasmic reticulum stress response elements, which can be altered leading to cell death. In the course of this study, we verified the expression of genes involved in the stress response of the endoplasmic reticulum in HepG2/C3A cells. The ?-tomatine reduced the viability of HepG2/C3A cells in a dose-dependent manner. Thus, we selected 2µg/mL of ?-tomatine (62% in cell viability) to evaluate the gene expressions. After 24 hours of exposure to ?-tomatine, the level of HSPA5 transcripts was reduced. The HSPA5 chaperone reduced marker is an indicative of homeostasis unbalance with the consequent lack of cellular resistance and, probably, cell death. Our results indicate the involvement of oxidative stress mechanisms in the death of HepG2/C3A cells exposed to ?-tomatine and show the effectiveness of the system as a future candidate for the cancer therapy studies.

Tomato (Solanum lycopersicum) contains α-tomatine, a steroidal glycoalkaloid that contributes to the plant defense against pathogens and herbivores through its bitter taste and toxicity. It accumulates at high levels in all the plant tissues, especially in leaves and immature green fruits, whereas it decreases during fruit ripening through metabolic conversion to the nontoxic esculeoside A, which accumulates in the mature red fruit. This study aimed to identify the gene encoding a C-27 hydroxylase that is a key enzyme in the metabolic conversion of α-tomatine to esculeoside A. The E8 gene, encoding a 2-oxoglutalate-dependent dioxygenase, is well known as an inducible gene in response to ethylene during fruit ripening. The recombinant E8 was found to catalyze the C-27 hydroxylation of lycoperoside C to produce prosapogenin A and is designated as Sl27DOX. The ripe fruit of E8/Sl27DOX-silenced transgenic tomato plants accumulated lycoperoside C and exhibited decreased esculeoside A levels compared with the wild-type (WT) plants. Furthermore, E8/Sl27DOX deletion in tomato accessions resulted in higher lycoperoside C levels in ripe fruits than in WT plants. Thus, E8/Sl27DOX functions as a C-27 hydroxylase of lycoperoside C in the metabolic detoxification of α-tomatine during tomato fruit ripening, and the efficient detoxification by E8/27DOX may provide an advantage in the domestication of cultivated tomatoes., (© The Author(s) 2021. Published by Oxford University Press on behalf of Japanese Society of Plant Physiologists. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)