Hernandulcin (HE) is a non‐caloric sweetener synthesized by the Mexican medicinal plant Phyla scaberrima. Herein we present the results of HE production through cell suspensions of P. scaberrima as well as the influence of pH, temperature, biosynthetic precursors and potential elicitors to enhance HE accumulation. The incorporation of mevalonolactone (30–400 mg L−1) farnesol (30–400 mg L−1), AgNO3 (0.025–0.175 M), cellulase (5–60 mg L−1; 0.3 units/mg), chitin (20–140 mg L−1) and (+)‐epi‐α‐bisabolol (300‐210 mg L−1) to the cell suspensions, resulted in a differential accumulation of HE and biomass. Among elicitors assayed, chitin, cellulase and farnesol increased HE production from 93.2 to ∼160 mg L−1 but, (+)‐epi‐α‐bisabolol (obtained by a synthetic biology approach) increased HE accumulation up to 182.7 mg L−1. HE produced by the cell suspensions was evaluated against nine strains from six species of gastrointestinal bacteria revealing moderate antibacterial activity (MIC, 214–465 μg mL−1) against Staphylococcus aureus, Escherichia coli and Helicobacter pylori. Similarly, HE showed weak toxicity against Lactobacillus sp. and Bifidobacterium bifidum (>1 mg mL−1), suggesting a selective antimicrobial activity on some species of gut microbiota. According to our results, chitin and (+)‐epi‐α‐bisabolol were the most effective molecules to enhance HE accumulation in cell suspensions of P. scaberrima.
Zanthoxylum limoncello is a native plant from southern Mexico which is used as a timber source, condiment and as a traditional medicine. Herein, we report on the volatile content of the leaf essential oil and its biological activities. The annual essential oils (2015-2018) contained volatile organic compounds which exhibited a moderate growth inhibitory activity against H. pylori ATCC 53504 (MIC 121.4-139.7 μg mL À 1 ), 26695 (MIC 85.5 -94.9 μg mL À 1 ) and J99 (MIC 94.7 -110.4 μg mL À 1 ). These hydrodistillates contained 2-undecanone (31.6-36.8 %; MIC 185.3 -199.2 μg mL À 1 ) and 2-undecenal (25.1-35.7 %; MIC 144.8 -111.3 μg mL À 1 ) as the most abundant compounds which were partially involved in the anti-H. pylori activity. The human ornithine decarboxylase enzyme (ODC1), which shows increased activity in several cancer types, was non-competitively inhibited (V max 2.7 > 0.8 K cat s À 1 ) by the essential oil of Z. limoncello as well as by 2-undecanone and 2-undecenal in accordance to in vitro kinetic studies. In silico calculations strongly suggest that the carbonyl group of these oxygenated hydrocarbons interacts with both Asn319 and Ala39 at the subunit A of ODC1. Considering that Ala39 is located close to Asn44, a crucial amino acid of the ODC's allosteric site, the non-competitive inhibition of the enzyme by 2-undecanone and 2-undecenal is endorsed. Finally, the essential oil of Z. limoncello and its main volatiles showed a significant (p < 0.01) and prolonged repellent effect against Aedes aegypti.[a] RI 1 , RI 2 , Retention index obtained with HP-5 ms and Factor Four VF5-ms, respectively. Abundances are presented as the average of five different samples (n = 5). [b] Indicates corroboration by co-injection with authentic standards.
The present article describes the chemical composition and biological activities of the essential oils of B. glabrifolia leaves obtained in four consecutive years (2015-2018). The essential oils contained α-terpineol (17.9-29.7 %), α-terpinene (12.6-17.4 %), limonene (14.9-26.8 %) and β-pinene (2.1-16.7 %) as the most abundant volatiles. The essential oils and these volatiles showed a significant adulticide activity (p<0.01; LC <100 μg mL ) on the maize weevil (Sitophilus zeamais) with a 100 % mortality rate within a period of 5 h. Also, the essential oils showed a strong antibacterial activity on Enterococcus faecalis ATCC 29212 (MIC, 132.7-173.6 μg mL ) and Helicobacter pylori ATCC 43504 (MIC, 74.8-199.2 μg mL ). The assessment of the main volatiles revealed α-terpineol as the principal antibacterial agent (MIC, 78.6-149.7 μg mL ). Similarly, the essential oils exhibited a substantial in vitro antiproliferative activity on the human prostate cancer cell lines PC-3 (LC , 15.2-19.4 μg mL ), the human ovarian carcinoma cell lines OVCAR-3 (LC , 27.3-53.7 μg mL ) and the myelogenous leukemia cell lines K-562 (LC , 32.4-75.9 μg mL ). α-Terpineol (LC , 32.4-75.9 μg mL ) exhibited the strongest antiproliferative effect on these cancer cell lines (LC , 22.4-48.1 μg mL ).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.