Morphology, Anatomy, and Bioactivities of Solanum lasiocarpum Dunal Fruit

Abstract

Background and Objective: Despite its traditional medicinal use, comprehensive data on the morphology, anatomy, and biological activities of Ma-eok (Solanum lasiocarpum Dunal) fruit remain limited. This study investigated the fruit’s macroscopic and microscopic characteristics, alongside the phytochemical profile and biological activities of its lyophilized juice. Methods: Morphological and anatomical features were analyzed using stereomicroscopy, light microscopy, and scanning electron microscopy (SEM). Lyophilized fruit juice was evaluated for total phenolic (TPC) and flavonoid contents (TFC), as well as antioxidant (DPPH), anti-inflammatory (egg albumin denaturation), antimicrobial (agar diffusion), and DNA-protective (comet assay) activities. Results: The globose fruit (mean diameter 38 mm, weight 31 g) transitions from green to yellowish-orange upon ripening. SEM photographs revealed the presence of dense stellate trichomes of the porrect-geminate type on ripe fruits, whereas unripe fruits exhibited both non-glandular trichomes and additional glandular trichomes. Anatomical examination revealed that the exocarp consists of a single epidermal layer underlain by a hypodermal layer of calcium oxalate crystal-bearing cells, as indicated by field emission scanning electron microscope equipped with an energy dispersive X-ray spectrometer (FE-SEM-EDS) analysis, followed by 5–6 layers of parenchyma.  The mesocarp consisted of parenchymatous tissue enclosing a thin and delicate endocarp. The locules contained a gelatinous matrix surrounding numerous kidney-shaped seeds with reticulate seed coats. Phytochemically, the lyophilized extract yielded a TPC of 68.13 ± 5.39 mg GAE/g and a TFC of 2.57 ± 0.01 mg QE/g. The fruit demonstrated strong antioxidant activity, with a value of 141.95 ± 0.02 mg TE/g, and significantly mitigated H₂O₂-induced DNA damage, as evidenced by comet assay results (P < 0.05). Antimicrobial testing demonstrated inhibitory activity against Staphylococcus aureus (12.0 ± 1.0 mm), Escherichia coli (9.7 ± 1.2 mm), and Cutibacterium acnes (9.7 ± 1.2 mm), whereas no inhibitory effect was observed against Candida albicans. Evaluation of anti-inflammatory activity was not feasible, as the high acidity of the extract induced premature protein precipitation during the assay.  Conclusion: The established pharmacognostic data and biological activities provide robust evidence supporting the potential use of Ma-eok fruit juice in value-added foods, nutraceuticals, and cosmetics.