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The results of this investigation confirm metabolomics as a useful tool in the detection of bioactive metabolites in plants without previous phytochemical studies. Copyright © 2017 John Wiley & Sons, Ltd.

The Yucatan Peninsula possesses a unique climate, geology, landscape, and biota that includes a distinct flora of over 2300 species; of these, close to 800 plants are used in what is known as Mayan traditional medicine, and about 170 are listed as native or endemic. Even though the flora of the Yucatan peninsula has been widely studied by naturalists and biologists, to date, phytochemical and pharmacological knowledge of most of the plants, including the medicinal plants, is limited. Presently, phytochemical studies carried out on plants from the Yucatecan flora have resulted in the identification of a wide variety of natural products that include flavonoids, terpenoids, polyketides, and phenolics with cytotoxic, antiprotozoal, antibacterial, anti-inflammatory, analgesic, antioxidant, and antifungal activities. This review describes the main findings in over 20 years (1992 to 2018) of exploring the natural product diversity of the Yucatecan flora.

This study assessed the in vitro anthelmintic (AH) activity of methanol and acetone:water leaf extracts from Annona squamosa, A. muricata and A. reticulata against Haemonchus contortus eggs. The egg hatch test was used to determine the effective concentrations required to inhibit 50% of eggs hatching (EC50). The role of polyphenols on AH activity was measured through bioassays with and without polyvinylpolypyrrolidone (PVPP). Methanolic extracts mainly caused the death of eggs at the morula stage (ovicidal activity). Meanwhile, acetone:water extracts caused egg-hatching failure of developed larvae (larvae failing eclosion (LFE) activity). The lowest EC50 values against H. contortus eggs were observed for the methanolic extracts from A. reticulata and A. muricata (274.2 and 382.9 µg/ml, respectively). From the six extracts evaluated, the methanolic extracts of A. muricata, A. reticulata and A. squamosa showed the highest ovicidal activity, resulting in 98.9%, 92.8% and 95.1% egg mortality, respectively. When the methanolic extract of A. squamosa was incubated with PVPP, its AH activity increased. Similarly, when acetone:water extracts of A. muriata and A. reticulata were incubated with PVPP, their LFE activity increased. Alkaloids were only evident in methanolic extracts, irrespective of PVPP incubation. The presence of acetogenins was not observed. In conclusion, methanolic extracts obtained from leaves of A. muricata, A. reticulata and A. squamosa showed ovicidal activity affecting the morula of H. contortus eggs, with minor LFE activity. Meanwhile, acetone:water extracts showed mostly LFE activity, with a lower proportion of ovicidal activity.

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It has been suggested that the anthelmintic (AH) activity of tannin-rich forages is related to their tannin content. However, reports on tropical fodders such as Lysiloma latisiliquum describe the same AH activity after the addition of tannin-blocking agents, suggesting that the activity either depends on the method of tannin blocking/removal or is due to other type of secondary metabolites. This study compared both the effect of the drying process of the plant material and the effect of different polyphenol removal methods on the AH activity of L. latisiliquum acetone-water extracts when tested against Haemonchus contortus. The results showed that the extraction of oven-dried (OD) leaves of L. latisiliquum yielded a CT-free extract with high AH activity. However, polyphenol-free fractions showed similar or lower AH activity levels as of those original OD extract. HPLC analysis confirmed that common polyphenolic metabolites are not responsible for the AH activity of L. latisiliquum.

Revista Brasileira de Farmacognosia xxx (2015) xxx-xxx w w w . s b f g n o s i a . o r g . b r / r e v i s t a Original Article a b s t r a c t Aphelandra scabra (Vahl) Sm., Acanthaceae, is a shrub widely used by some Mayan communities as carminative, antidote, and remedy for some infections. Bio-guided isolation of the methanol extract of leaves led us to the purification of the anti-giardial metabolites cirsimaritin and sorbifolin, along with the inactive metabolites cirsimarin, sorbifolin-6-O-␤-glucopyranoside, and squalene. Cirsimaritin displayed high activity in the anti-giardial bioassay with an IC 50 = 3.8 M, being considered as outstanding when compared to previous reported metabolites, while sorbifolin showed a low activity with an IC 50 = 75.6 M. Additionally, both compounds proved not to be cytotoxic in an in vitro bioassay against HEK-293, a normal cell line. This is the first investigation on anti-giardial properties of A. scabra and its phytochemistry as well, thus the isolated compounds are considered as new for the plant genus and for the species.

In the present study, the leaves of Manilkara zapota (L.) P. Royen (Sapotaceae), an evergreen tree recognized for its medicinal properties in Southern Mexico, were used as a model to study the effect of different drying temperatures on its metabolic profile and therefore, its antioxidant potential. For this purpose, a methanol extraction of leaves dried at room temperature (25 °C) or by heat convection (50, 75 and 100 °C) were compared in terms of drying efficiency, yield of extraction, total phenol content, 1H-NMR metabolic profile, and DPPH antioxidant activity. The drying curves enabled the fact to be uncovered that drying efficiency improves with increase of temperature, as does the level of total phenols and antioxidant activity. A metabolomics approach using principal component analysis (PCA) and orthogonal projections to latent structures discriminant analysis (OPLS-DA) of the corresponding 1H-NMR profiles allowed the impact of the drying temperature on their metabolic profile to be documented and also, caffeic acid and epicatechin as main secondary metabolites contributing to the antioxidant activity of M. zapota to be identified.