Hydropriming Applied on Fast Germinating Solanum villosum Miller Seeds: Impact on Pre-germinative Metabolism

Seed priming can circumvent poor germination rate and uniformity, frequently reported in eggplant (Solanum melongena L.) and its crop wild relatives (CWRs). However, there is still a gap of knowledge on how these treatments impact the pre-germinative metabolism in a genotype- and/or species-dependent manner. The CWR Solanum villosum Miller (hairy nightshade) investigated in this study showed a quite unique profile of fast germination. Although this accelerated germination profile would not apparently require further improvement, we wanted to test whether priming would still be able to impact the pre-germinative metabolism, eventually disclosing the predominant contribution of specific antioxidant components. Hydropriming followed by dry-back resulted in synchronized germination, as revealed by the lowest MGR (Mean Germination Rate) and U (Uncertainty) values, compared to unprimed seeds. No significant changes in ROS (reactive oxygen species) were observed throughout the treatment. Increased tocopherols levels were detected at 2 h of hydropriming whereas, overall, a low lipid peroxidation was evidenced by the malondialdehyde (MDA) assay. Hydropriming resulted in enhanced accumulation of the naturally occurring antioxidant phenolic compounds chlorogenic acid and iso-orientin, found in the dry seeds and ex novo accumulation of rutin. The dynamic changes of the pre-germinative metabolism induced by hydropriming are discussed in view of future applications that might boost the use of eggplant CWRs for breeding, upon upgrade mediated by seed technology.

Antidiabetic properties of Solanum villosum and Solanum nigrum var sarrachoides in a streptozotocin-induced diabetic mice model

Background: Diabetes mellitus (DM) poses immense challenge to the health of people worldwide. Current therapies are limited by cost and adverse effects. Solanum nigrum, a complex of many species in the family Solanaceae has been recorded to be used by many communities in the management of DM. The aim of this study was to evaluate the phytochemical, antidiabetic efficacy and safety of two species, namely; Solanum villosum and S. nigrum var sarrachoides using streptozotocin-induced diabetic mice model.Methods: Qualitative assessment for phytochemical constituents was carried out. Acute toxicity was conducted based on ‘Organisation of Economic Cooperation and Development’ 2001 guidelines. Diabetes was induced by injection of streptozotocin at a dose of 200 mg/kg body weight intraperitoneal after the mice fasted for 8 hours. Aqueous extracts were administered orally using an oral gavage at doses of 150, and 300 mg/kg body weight for each plant daily and monitored weekly for 28 days.Results: Both plants contain vital phytochemicals. Flavonoids, alkaloids, tannins, saponins, phenols, and glycosides were present in both plants. However, phytosterols and coumarins were absent in S. villosum. Additionally, both plants did not show toxicity. Both plants showed efficacy with S. nigrum var sarrachoides being more potent at both doses.Conclusions: The study validates the use of these plants by herbalists and recommends further studies on them with the aim of elucidating the active compounds that can be used as novel therapies for diabetes. Additionally, the study recommends the evaluation of other species in this complex for antidiabetic properties.