Search Results (9)

Background/Objectives: Natural products are gaining increasing importance due to the large variety of biological activities exerted by their constituents. Among these, the products deriving from Acmella oleracea (L.) R.K. Jansen can be exploited for their local anaesthetic, myorelaxant, anti-inflammatory/analgesic, and antifungal properties. In this regard, there is a need to develop novel formulations for the topical delivery of A. oleracea-derived extracts to widen their use in the pharmaceutical and cosmetic fields. Methods: Nanoformulations, i.e., nanoemulsions (NEs) and microemulsions (MEs), were investigated as a strategy to encapsulate an extract from A. oleracea at the nanoscale level in water and then incorporated into xanthan gum-based hydrogels. Results: Only NEs provided a physically stable formulation, while the precipitation of solid hydrophobic components from the extract was observed during ME preparation under all tested conditions despite the use of ethyl oleate as an oily co-solvent. The optimized NE-based hydrogel remained physically stable over six months, as confirmed by rheological measurements and polarized optical microscope observation, without a phase separation phenomenon. Therefore, NEs resulted more suitable nanodispersed systems than MEs for the encapsulation of A. oleracea extract, which contains a large amount of hydrophobic constituents that are solid at room temperature. Furthermore, the sustained spilanthol release across an artificial membrane (Franz cell apparatus) and the cytotoxic profile on HaCaT cell line support its potential topical application. Conclusions: The outcomes of this study provided valuable insights into the formulation of A. oleracea extract, broadening its fields of applicability, including topical administration. Full article

Acmella oleracea (L.) R.K. Jansen, also called jambù, is a medicinal and aromatic plant native to the Brazilian Amazon rainforest and phytochemically characterized by N-alkylamides with spilanthol as the main active compound. Jambù recently attracted the interest of many companies because of its wide range of pharmaceutical, nutraceutical, and cosmetic applications. In this context, it is desirable to identify eco-friendly cultivation methods that not only minimize the environmental footprint but also support the biosynthesis of the plant’s valuable bioactive compounds. The zero-discharge approach of aquaponics makes this growing system an eco-friendly and sustainable production strategy for crops. Thus, a greenhouse experiment was conducted on two jambù cultivars, i.e., cv ‘purple’ and cv ‘yellow’, grown in aquaponic and hydroponic systems. The objective was to compare their contents of N-alkylamides, their numbers of capitula, which are the main source of these bioactives, and their volatile profiles. The results highlighted differences between the two cultivars and among plants harvested at different periods. Interestingly, aquaponics yielded plants with a high N-alkylamide content, which was comparable to that obtained with hydroponics. Overall, this study highlighted the feasibility of adopting aquaponics to grow A. oleracea, paving the way for circular economy-based and sustainable agricultural practices. Full article

This study investigates the transformation of Acmella oleracea with the Agrobacterium rhizogenes rolC gene and evaluates its impact on phytochemical composition and biological activity. A total of 480 plant nodes were subjected to Agrobacterium−mediated transformation, leading to the regeneration of 35 putative transgenic plants. Molecular analysis confirmed the presence of the rolC transgene in 17 clones, of which four (C123, C127, C129, and C132) exhibited rolC mRNA expression. Phytochemical profiling of hydroalcoholic extracts of aerial parts (AP) and roots (R) revealed significant differences (p ≤ 0.05) between transgenic and non-transgenic plants (CTR). Compared to non−transgenic plants, transgenic AP exhibited lower total phenolic content but retained or increased flavonoid concentrations, particularly flavan−3−ols, whereas R extracts consistently showed reduced secondary metabolite levels. LC−DAD−ESI−MS analysis identified a diverse metabolite profile, with AP being notably rich in flavonoids (48.65%) and alkylamides (32.43%), including spilanthol. Functional assessments across antioxidant and anti−inflammatory assays demonstrated that R extracts exhibited stronger bioactivity compared to AP extracts, as indicated by lower IC₅₀ values (0.004–2.18 mg/mL for R vs. 0.007–7.24 mg/mL for AP). However, iron−chelating capacity was higher in AP extracts, correlating with flavonoid concentration. Hierarchical clustering confirmed that transgenic lines C123 and C127 most closely resembled the control, while C129 and C132 displayed distinct metabolic profiles. These findings highlight rolC’s role in modulating secondary metabolite synthesis, influencing both the phytochemical composition and functional properties of A. oleracea extracts. Full article

For the first time, this work reports the seasonal influence on the chemical composition and antiradical capacity of Acmella oleracea floral essential oil, produced from a perennial herb of great nutritional and pharmacological importance in the Amazon region. The species was cultivated and the plantation was monitored from May to September 2022 between the rainy and dry seasons. The essential oils were obtained by hydrodistillation, analyzed by gas chromatography coupled with a mass spectrometer, and subjected to the free radical inhibition assay using the DPPH method. The highest oil yield (1.61%) occurred in May (rainy season), and the lowest (0.68%) occurred in September (dry season). Despite the difference in the oil yield between the rainy and dry seasons, no significant correlation with weather conditions (p > 0.05) occurred. During the collection period, the class of sesquiterpene hydrocarbons was predominant (16.35–46.01%). The main constituents of A. oleracea were E-caryophyllene (13.57–25.74%), caryophyllene oxide (0.88–31.72%), 1-pentadecene (5.42–16.58%), germacrene D (0.14–15.17%), and myrcene (1.08–11.99%), and a low concentration of its main bioactive spilanthol (0.66–5.2%) was also observed. The antiradical capacity was considered low, with inhibition of 7.96 to 7.53% of free radicals and a Trolox equivalence of 68.4 to 64.7 mg·ET/g. Although there were some changes in the levels of chemical components in A. oleracea essential oils, the species can be considered an alternative source of pharmacologically active compounds such as E-caryophyllene and caryophyllene oxide, in addition to presenting amounts of other bioactive molecules. Full article

Spilanthol is a major N-alkylamide constituent of Acmella oleracea (L.) R.K. Jansen with diverse pharmacological properties. We recently showed the applicability of NADES (natural deep eutectic solvents) for the green extraction of spilanthol. However, the purification of targets from NADES poses a challenging step due to their non-volatility. A simple green method to retrieve spilanthol with minimal instrumental effort was devised, fractioning NADES (choline chloride/methylurea, choline chloride/1,2-propanediol, choline chloride/citric acid) and dry ethanolic extracts by SPE on C18 material, eluting merely with ethanolic solutions. The relative distribution of spilanthol and organic adulteration in SPE fractions were detected by HPLC-DAD, followed by scale-up, quantification and purity determination in an NMR-based approach. Isocratic elution with 52% ethanol (v/v) proved suitable in all experiments. The three purest 10 mL fractions combined yielded 12.21 mg spilanthol at 71.65% purity from NADES extract ChCl/P (choline chloride/1,2-propanediol, molar ratio 1:2, +20% m/m water). Ethanolic extract samples showed purities ranging from 77.27 to 80.27% in combined raw fractions. For all samples, purity increased by removing non-soluble substances from organic solutions. Pooled NADES extract fractions showed 89.71% in final samples, ethanolic extracts 87.25 to 91.93%. The highest purities of individual fractions per extract were 89.23 to 94.15%. This cheap and simple purification process is promising to acquire spilanthol for research purposes or as a sample preparation step before HPLC on a semi-preparative to preparative scale, as the substance is highly priced and scarcely available on the market. Organic solvents can be reused, and preliminary scale-up possibilities are shown. Full article

Motivated by the culinary and ethnopharmacological use of Acmella oleracea (L.) R.K. Jansen, this study aimed to unveil new chemical compounds from its essential oil (EO). Acmella oleracea, known for its anesthetic and spicy properties, has been used in traditional medicine and cuisine, particularly in Northern Brazil. Through a detailed GC-MS analysis, 180 constituents were identified, including 12 tentatively identified long-chain α-keto esters of various acids. Additionally, 18 new esters were synthesized for structural verification. This research expands the known chemical diversity of A. oleracea EO, providing a basis for potential pharmacological applications. The identification of new natural products, including homologs and analogs of acmellonate, underscores the EO’s rich chemical profile and its potential for novel bioproduct development. Full article

With a growing focus on green chemistry, the extraction of natural products with natural deep eutectic solvents (NADES), which are eutectic mixtures of hydrogen bond donors and acceptors, has become an ever-expanding field of research. However, the use of NADES for the extraction of spilanthol from Acmella oleracea (L.) R.K.Jansen has not yet been investigated. Therefore, in this study, 20 choline chloride-based NADES, and for comparison, ethanol, were used as green extraction agents for spilanthol from Acmella oleracea flower heads. The effects of time, water addition, and temperature on NADES extractions were investigated and analysed by HPLC-DAD quantification. Additionally, UHPLC-DAD-ESI-MSⁿ results for dichloromethane extracts, as well as the isolation of spilanthol and other main constituents as reference compounds, are reported. The best green extraction results were achieved by choline chloride (ChCl) with 1,2-propanediol (P, 1:2 molar ratio, +20% water) at 244.58 µg/mL, comparable to yields with ethanol (245.93 µg/mL). Methylurea (MeU, 1:2, +20% water) also showed promising results as a hydrogen bond donor in combination with choline chloride (208.12 µg/mL). In further experiments with NADES ChCl/P (1:2) and ChCl/MeU (1:2), extraction time had the least effect on spilanthol extraction with NADES, while yield decreased with water addition over 20% and increased with extraction temperature up to 80 °C. NADES are promising extraction agents for the extraction of spilanthol, and these findings could lead to applicable extracts for medicinal purposes, due to their non-toxic constituents. Full article

The production of biodegradable food packaging with innovative characteristics is a current challenge that contributes to sustainable development and guarantees greater consumer safety. Thus, this review reports the general characteristics of jambu, highlighting the nutritional and medicinal importance, the rich composition of bioactive compounds and, mainly, the advances in the application of the plant as a multifunctional material for food packaging. The possibility of using jambu in active and “intelligent” films was identified. The addition of bioactive compounds to films can influence the physical, biochemical and sensory properties of foods, increasing the shelf life of packaged products, in addition to adding more economic value to the plant. According to the knowledge obtained by the authors of this review, information about the potential application of bioactive compounds from jambu in the development of films for biodegradable packaging will be presented for the first time in this review. Therefore, this study will provide researchers, food scientists and academics with a more comprehensive understanding of sustainable food packaging, with a focus on active and “intelligent” properties, contributing to the development of future research. Full article

Human pathologies, environmental pollution, and resistance phenomena caused by the intensive use of chemical pesticides have shifted the attention of the agrochemical industries towards eco-friendly insecticides and acaricides. Acmella oleracea (L.) R. K. Jansen (jambù) is a plant native to South America, widely distributed and cultivated in many countries due to its numerous pharmacological properties. This review analyzes literature about the plant, its uses, and current knowledge regarding insecticidal and acaricidal activity. Acmella oleracea has proven to be a potential pesticide candidate against several key arthropod pest and vector species. This property is inherent to its essential oil and plant extract, which contain spilanthol, the main representative of N-alkylamides. As a result, there is a scientific basis for the industrial exploitation of jambù in the preparation of green insecticides. However, studies related to its toxicity towards non-target species and those aimed at formulating and developing marketable products are lacking. Full article