Search Results (3)

An eco-friendly microemulsion biofungicide derived from Allamanda cathartica was developed for the control of papaya anthracnose caused by Colletotrichum gloeosporioides. The formulation was prepared by blending surfactants, carrier oil, and water and optimized using ternary phase diagrams to identify stable microemulsion systems. All selected formulations exhibited surface tension values ranging from 29 to 31 mN/m, while particle sizes ranged from 51.79 to 1801.05 nm. The optimized formulation, coded as AM8, consisted of 35% Allamanda concentrated liquid crude extract (ACLCE), 26% water, 13% alkyl polyglucoside surfactant, and 26% dimethylamide oil. Papaya fruits coated with the formulations showed significant reductions (p < 0.05) in anthracnose incidence caused by C. gloeosporioides. Control fruits treated with water showed 75% disease incidence, whereas fruits treated with benomyl showed 42% disease incidence. Disease incidence, severity, and disease index decreased with increasing formulation concentration, and fruits treated with the eight formulations at 10% concentration exhibited significantly lower disease incidence (0–17%) and disease index (0–17%), with disease severity consistently scored as zero. The Allamanda formulation demonstrated strong antifungal activity with EC₅₀ and EC₉₅ values of 1.839 and 7.067 mg/mL (w/v), respectively, at the 95% confidence level. The optimized formulation AM8 remained stable for up to one year and showed superior disease control performance compared with the conventional fungicide benomyl. In addition, the formulation maintained fruit quality by preserving firmness, peel color, and soluble solids concentration, thereby extending papaya shelf life up to 30 days without adversely affecting the natural ripening process. These findings demonstrate the potential of Allamanda-based microemulsion formulations as sustainable biofungicides for postharvest control of papaya anthracnose and provide a promising alternative to conventional synthetic fungicides. Full article

In this article, we propose to explore the chemical interaction between Pseudosphinx tetrio L. and Allamanda cathartica L. using different analytical methods, including an innovative electrochemical approach (called electrochemical ecology) and multivariate analysis, and we investigate the potential antimicrobial effects (antibacterial and antifungal activities) of this interaction in order to gain a better understanding of their specific interaction. The analytical study presents a similar chemical profile between the leaves of healthy and herbivorous A. cathartica and the excretions of the caterpillars. The similar analytical profile of the leaves of A. cathartica and the excretions of P. tetrio, and the difference with the caterpillar bodies, suggests a selective excretion of compounds by the caterpillar. The measured antimicrobial activities support the physicochemical tests. The natural products found selectively in the excretions (rather than in the body) could explain the ability of P. tetrio to feed on this toxic Apocynaceae species. Full article

In this work, we explore the current knowledge about the phytochemistry and in vitro and in vivo evaluations of the extracts and, where appropriate, the main active components characterized and isolated from the Allamanda cathartica. Of the 15 Allamanda species, most phytochemical, pharmacological, and toxicological studies have focused on A. cathartica. These plants are used for the treatment of various health disorders. Numerous phytochemical investigations of plants from the A. cathartica have shown the presence of hydrocarbons, alcohols, esters, ethers, aldehydes, ketones, fatty acids, phospholipids, volatile compounds, phenolic compounds, flavonoids, alkaloids, steroids, terpenes, lactones, and carbohydrates. Various studies have confirmed that extracts and active substances isolated from the A. cathartica have multiple pharmacological activities. The species A. cathartica has emerged as a source of traditional medicine used for human health. Further studies on the phytochemical, pharmacological, and toxicological properties and their mechanisms of action, safety, and efficacy in the species of A. cathartica is recommended. Full article