REMARKABLE ANTI-TRYPANOSOMA CRUZI ACTIVITY IN SELECTED SALVADORAN PLANT SPECIES

REMARKABLE ANTI-TRYPANOSOMA CRUZI ACTIVITY IN SELECTED SALVADORAN PLANT SPECIES

U. G. Castillo, K. Alas, M. Mejía, G. Cerén, W. D. Castro-Godoy, R. M. Guerrero, J. Menjívar, M. L. Martínez, C. E. Arias, J. Nakajima-Shimada and M. J. Núñez *

Laboratorio de InvestigaciónenProductos Naturales (LIPN), Facultad de Ciencias Naturales y Matemática, Universidad de El Salvador, San Salvador Centro 1101, El Salvador.

ABSTRACT: In Latin America, Chagas is one of the most prevalent diseases, and current chemotherapy with benznidazole and nifurtimox is ineffective in chronic phase. Therefore, the development of new drugs, especially for the chronic stage of the infection, is urgently needed. Performing an in-vitro anti-trypanosome assay, we analyzed 114 plant species from Salvadoran flora, resulting in 34 active plants against epimastigote of Trypanosoma cruzi belonging mainly to the botanical families Piperaceae, Asteraceae, Salicaceae, Annonaceae, and Acanthaceae. Thus, nine of them showed prominent activity between 91.18 to 98.94% of viability suppression at 100 µg/mL (Annona holosericea, Calea urticifolia, Eremosis leiocarpa, Peperomia pseudoalpina, Piper amalago, Piper martensianum, Casearia corymbosa, Piparea dentata and Solanum nudum), highlighting C. corymbosa, P. pseudoalpina and P. martensianum as the most promising species as sources of natural compounds useful for the treatment of Chagas disease. P. speudoalpina and P. martensianum do not have reports of their phytochemical composition or biological activities.

Keywords: Chagas, Trypanosoma cruzi, Epimastigote, El Salvador

INTRODUCTION: Chagas disease is caused by Trypanosoma cruzi protozoan and affects around 6-7 million people in Latin America causing around 50,000 deaths per year. On the other hand, 65-100 million people are living in infection risk ¹. A study on Chagas disease in El Salvador has provided important epidemiological information between the years 2018 through 2020, including a 34.4% infection rate among triatomines, vectors of Chagas disease, and a 2.3% seropositivity rate for pediatric Chagas in Sonsonate. In 2022, a maternal surveillance study showed a 6% T. cruzi positivity rate among pregnant women ². During that year, the Ministry of Public Health reported 52 acute and 894 chronic suspected Chagas cases ³.

Plant-derived natural products are essential in drug discovery and development, providing a rich source of bioactive molecules with diverse properties. In fact, a quarter of currently useful drugs are derived from medicinal plants. This is especially important in regions where trypanosomiases are prevalent ⁴. Countries like El Salvador, which have abundant medicinal plant resources, are of particular interest. Some of these plants and their compounds have demonstrated efficacy in-vitro against T. cruzi ^{5, 6}. Herein, we report the in-vitro activity of 114 plant species from 14 botanical families against T. cruzi epimastigotes. Notably, nearly 30% of the evaluated species exhibited antitrypanosomal activity.

MATERIALS AND METHODS:

Plant Selection: The species were selected based on the results of a previous investigation ⁵, in which certain families and botanical genera existing in the Salvadoran flora were promising. 114 plant species were collected in different areas of El Salvador in 2019-2022 and identified by Jenny Elizabeth Menjívar Cruz from the Museo de Historia Natural de El Salvador and Gabriel Cerén from the Escuela de Biología, Universidad de El Salvador. A voucher specimen has been deposited for each species in the Herbarium at the MHES Table 1.

Preparation of Plant Extracts: The listed plants in Table 1 were ground to a particle size of less than 2 mm (Bel-Art products, USA, model micro-mill) after drying at 40 °C for 48 to 72 hours in an air-circulating oven (BIOBASE, China, model BOV-V225F). An ultrasonic bath with magnetic stirrer (VWR, USA, model 97,043-988, operating frequency 35 kHz) was used to extract 20 grams of each sample over the course of 90 minutes at 25 °C. Each extract was concentrated under reduced pressure at 40 °C (model RE801, Yamato Scientific Co., Ltd., Japan) to create the crude MeOH extracts.

TABLE 1: ANTITRYPANOSOMAL ACTIVITY OF SALVADORAN SPECIES AGAINST EPIMASTIGOTE STAGE OF TRYPANOSOMA CRUZI

Scientific names according to The World Flora Online (July 7^th, 2024): http://www.worldfloraonline.org. Place: Coatepeque Lake, El Congo, Santa Ana (1); University of El Salvador, San Salvador (2); Cantón Zapúa, Jujutla, Ahuachapán (3); Cantón El Limo, Metapán, Santa Ana (4); Cantón Pushtán, Nahuizalco, Sonsonate (5); Guazapa Hill, Guazapa, San Salvador (6); Las Termopilas Farm, Chiltiupán, La Libertad (7); San Jorge Farm, San Julián, Sonsonate (8); PNA San Diego La Barra, Metapán, Santa Ana (9); NP Montecristo, Metapán, Santa Ana (10); Volcano NP, Santa Ana (11); EP El Manzano, Dulce Nombre de María, Chalatenango (12); Verde Lagoon, Apaneca, Ahuachapán (13); Cantón El Amatillo, Las Vueltas, Chalatenango (14); El Pacayal Volcano, Chinameca, San Miguel (15); Las Ninfas Lagoon, Apaneca, Ahuachapán (16) and Chichicastepec Hill, Apaneca, Ahuachapán (17); PNA: Protected Natural Area; NP: National Park and EP: Ecological Park. The viabilities are represented by means of three replicates ± standard deviations (SD).

Antitrypanosomal Screenig of Crude Extracts: The antitrypanosome luminescence assay was performed as described by Castillo et al. 2022 ⁵, with some modifications. In white 384-well plates (Optiplate, Perkin Elmer) 50 µL of Trypanosoma cruzi epimastigotes (strain CL-Brener) at a concentration of 9x105 suspended in GIT medium supplemented with hemin (5 mg/500 mL) and 10% inactivated fetal bovine serum were placed. These were incubated at 28°C for 24 hours after adding 0.5 µL of plant extracts at 10 and 1 mg/mL concentrations in DMSO. Each extract was evaluated in triplicate. Benznidazole and Tamoxifen (10 mM, 5 mM, 1.25 mM, 0.25 mM) were used as positive control and GIT medium without epimastigotes, GIT medium with parasites plus DMSO and GIT medium with DMSO were used as blanks. After incubation, 20 µl of Cell Titer-Glo ® 2.0 reagent (PROMEGA) was added to each well and incubated for 15 minutes at 28°C protected from light. Luminescence was measured on a Biotek Synergy HTX multimode plate reader at 28°C. The results are expressed in viability percent see Table 1.

RESULTS: The antitrypanosomal screening was carried out with the resulting 127 methanolic dried extracts from 114 plant species collected Table 1.

FIG. 1: ANTITRYPANOSOMAL ACTIVITY OF SALVADORAN ACTIVE SPECIES AGAINST EPIMASTIGOTE STAGE OF TRYPANOSOMA CRUZI

The yields from aerial part extracts ranged from 4.6-17.9%, whole plant 6.2-20.7%, stem bark 4.3-22.1%, branches 2.3-4.8%, fruits 10.4-16.9%, and roots 3.5%. The activity of antitrypanosomal screening is expressed in viability percent and summarized in Table 1. Considering previous criteria ⁵, 34 species from 14 botanic families were considered as active (less than 50% of viability percent at 100 µg/mL) Fig. 1. The botanic families Piperaceae, Asteraceae, Salicaceae, Annonaceae, and Acanthaceae, exhibited the highest number of active botanical species, Fig. 2. Among these, the aerial parts (43%), leaves (34%), and whole plant (14%) were the organs and parts of the active plants that showed activity, followed by stem bark (6%) and fruits (3%) Table 1.

FIG. 2: ACTIVE SALVADORAN BOTANICAL FAMILIES AGAINST EPIMASTIGOTES OF TRYPANOSOMA CRUZI (VIALIBILITY < 50%)

DISCUSSION: From the 34 active species identified, only 9 demonstrated remarkable activity against T. cruzi epimastigote, showing more than 90% suppression of epimastigote viability at a concentration of 100 μg/mL Fig. 1 and Table 2. Among these, Annona holosericea (Annonaceae) exhibited a viability suppression of 91.18±0.52% at 100 µg/mL, Table 2. Annonaceae family and specifically the genus Annona is known to have a broad spectrum of biological activities, including antineoplastic, antiparasitic, cytotoxic, antitumoral, antiprotozoal, antidiabetic, anti-inflammatory, hepatoprotective, and analgesic properties ^{7, 8, 9}. There are no studies specifically addressing the antitrypanosomal activity of A. holosericea. However, A. crassiflorais traditionally used in the treatment of Chagas disease ^{10, 11}. Moreover, there are some reports that A. foetida, A. crassiflora, A. muricata, A. squamosa, A. haematantha, A. purpurea, A. coriacea, and A. senegalensis are active against T. cruzi ^{12, 7, 4} and some studies suggest that antitrypanosomal activity is attributed to alkaloids, acetogenins, and terpenes ^{10, 11, 12, 7}.

TABLE 2: SALVADORAN SPECIES WITH PROMINENT ANTITRYPANOSOMAL ACTIVITY AGAINST EPIMASTIGOTE STAGE OF TRYPANOSOMA CRUZI

Scientific names according to The World Flora Online:http://www.worldfloraonline.org (July 7^th, 2024). The viability suppressions are represented by means of three replicates ± standard deviations (SD).

Among the Asteraceae family exist many subfamilies, genera, and species, herbs and shrubs being the most common; this is a representative family for trypanocidal activity ^{13, 14 15}. In which alkaloids, flavonoids, phenolic acids, coumarins, terpenoids, quinolines and diterpenoids, triterpenoid sesquiterpene lactones, and pyrethrins are associated with antiparasitic activity ¹⁵.

In our results, Calea urticifolia showed an important activity (viability suppression at 100 µg/mL: 97.83±0.65%) against epimastigotes, Table 2; this specie is commonly known in El Salvador as “Juanislama” and used to treat gastric ulcers and as a bactericide ¹⁶. Some studies of C. urticifolia have resulted in the isolation of sesquiterpene lactones (germacranolides and heliangolides), some phenols, as well as isoeugenol and phloroglucinol derivatives ^{17, 18, 19, 14}.

This is the first report of antitrypanosomal activity for C. urticifolia,and it may be attributed to the presence of sesquiterpene lactones and phenolic compounds ¹⁵. On the other hand, C. uniflora has demonstrated in-vitro activity against trypomastigote form of T. cruzi ^{20, 21, 22}.

Regarding Eremosis leiocarpa is used in El Salvador to treat asthma ²³, and was known as Vernonia leiocarpa (viability suppression at 100 µg/mL: 91.18±1.71%) Table 2, this specie does not have any reports of antitrypanosome activity, but, some sesquiterpene lactones (glaucolide F, G and H) were detected in E. leiocarpa ²⁴ that could be antitrypanosomal promising compounds. Furthermore, species of this genera, including V. auriculifera, V. brasiliana, V. guineensis, V. subuligera, V. polyanthes, V. scorpioides have been identified as a source of trypanocidal compounds ^{23, 25}.

Among the species of the Piperaceae family that showed greater antitrypanosomal activity, Peperomia pseudoalpina (viability suppression at 100 µg/mL: 98.75±0.35%), Piper amalago (viability suppression at 100 µg/mL: 96.78±1.20%), and P. martensianum (viability suppression at 100 µg/mL: 98.38±0.50%) were found, Table 2. This botanic family is used in traditional medicine to treat several ailments and protozoal disease ^{26, 27, 5}, moreover, they are known for being a source of secondary metabolites with antitrypanosomal, antileishmanial, anxiolytic, anticonvulsant and antiinflammatory activities ²⁸.

Despite its biological importance and its prominent antitrypanosomal activity found out, Peperomia pseudoalpina is underexplored. Likewise, no report so far has been found in the literature on the phytochemical and biological screening also, some species of Peperomia genera have been reported with this activity ^{5, 6}. Additionally, some bioactive compounds were reported with trypanocide activity against epimastigote and trypomastigote of T. cruzi, such as tetrahydrofuran lignans ^{29, 30, 6}.

Tetrahydrofuran lignans being the presumed responsibles for the activity in Peperomia in the same way as phenylpropanoids. P. amalago has some pharmacological properties such as anti-inflammatory, antimicrobial, cicatrizing, antioxidant, and antileishmanial ^{31, 32}. Its phytochemical roots composition is mainly integrated by sesquiterpenes, pyrrolidines, and isobutylamides ³¹. Two pyrrolidine alkaloids (N-[7-(3', 4'-methylenedioxyphenyl) - 2(E), 4(E)-heptadienoyl] pyrrolidine and N-[7-(3', 4'-methylenedioxyphenyl)-2(Z), 4(Z)-heptadienoyl] pyrrolidine) have been tested against promastigotes of Leishmania amazonensis, showing promising results ²⁷. Additionally, a derivative compound was tried against epimastigote and amastigote forms of T. cruzi ³¹. On the other hand, P. martensianum does not have reports of its phytochemical composition nor biological activities, thus, this is the first report of biological activity attributed to this specie. Its promising activity could be related to benzoic acid derivatives and flavonoids as has been demonstrated in other studies of Piper species ^{28, 26, 5}.

Casearia genus belongs to Salicaceae family and is traditionally used for gastric disorders, wound healing, and as a topical anesthetic, anti-inflammatory, antiophidic, antipyretic, and antiseptic ³³. Among its species, C. corymbosa is the second most active specie against epimastigotes of T. cruzi, suppressing the 98.88% of viability at 100 μg/mL, Table 2. From its leaves and bark have been isolated some diterpenoids such as clerodane, labdane, kaurene, kolovanetypes, γ-sitosterol, and phenolic acids ^{34, 35, 36}. Even with its interesting chemical composition, the antitrypanosomal activity of C. corymbose-like Piparea dentata (previously known as Casearia commersoniana)-has not yet been thoroughly investigated. However, another species from the same genus, Casearia sylvestris, has been reported to have antitrypanosomal activity against T. cruzi ³⁷, supporting its applicability in this type of studies.

The aerial parts extract of P. dentata was the most active in this study, suppressing the 98.94% viability of epimastigotes of T. cruzi at 100 μg/mL, Table 2. This is the first report of biological activity; nevertheless, some reports of goat toxicity of its fruits have been reported ³⁸. Therefore, it is advisable to carry out toxicity studies on this species before delving into its phytochemical and biological studies. Solanum nudum (Solanaceae) fruits (viability suppression at 100 μg/mL:91.64±4.80%, Table 2) are used in traditional medicine to treat fevers ³⁹, and several steroids, and sapogenins have been isolated ^{40, 39, 41, 42}. Some of them presented antiplasmodial or antimalarial activity, and it was determined that none were mutagenic, clastogenic,or cytotoxic ^{39, 41, 42}. Toxicity studies are recommended, as the unripe fruits of many Solanum species exhibit toxicity to humans ⁴³.

CONCLUSION: From 114 tested species, 34 were active against T. cruzi epimastigotes, and it is interesting to highlight the prominent activity of 9 species (viability suppression > 90%). Not with standing, Casearia corymbosa, Peperomia pseudoalpina, and Piper martensianum are the most promising species according to their chemical composition, biological activities, and toxicity. Therefore, these species could be promising sources for isolating new compounds with therapeutic potential against Chagas disease.

This confirms that the Salvadoran flora is a rising source of antitrypanosomal species and antikinetoplastid agents.

ACKNOWLEDGMENTS: The Ministry of Environment and Natural Resources of El Salvador supported the collection of some of the plant species.

Funding: This work was supported by a Grant for Science and Technology Research Partnership for Sustainable Development (SATREPS) from the Japan Agency for Medical Research and Development (AMED) (JP: 20jm0110016h0004 and JP: 21jm0110016h0005) and the Japan International Cooperation Agency (JICA).

CONFLICT OF INTEREST: No conflict of interest was reported by the authors.

REFERENCES:

1. Cucunubá ZM, Gutiérrez-Romero SA, Ramírez JD, Velásquez-Ortiz N, Ceccarelli S, Parra-Henao G, Henao-Martínez AF, Rabinovich J, Basáñez MG, Nouvellet P and Abad-Franch F: The epidemiology of Chagas disease in the Americas. The Lancet Regional Health–Americas 2024; 37: 100881 https://doi.org/10.1016/j.lana.2024.100881
2. Núñez MJ, Martínez ML, Castillo UG, Flores KC, Menjívar J, López-Arencibia A, Bethencourt-Estrella CJ, Jiménez IA, Piñero JE, Lorenzo-Morales J and Bazzocchi IL: Salvadoran Celastraceae species as a source of antikinetoplastid quinonemethide triterpenoids. Plants 2024; 13(3): 360. https://doi.org/10.3390/plants13030360
3. MINSAL M de S de ESD de E. Casos sospechosos de Chagas agudo y crónico [Internet]. [place unknown].https://dvs.salud.gob.sv/2022
4. Nekoei S, Khamesipour F, Habtemariam S, de Souza W, Pour PM and Hosseini SR: The anti-Trypanosoma activities of medicinal plants: A systematic review of the literature. Veterinary Medicine and Science 2022; 8: 2738–2772. https://doi.org/10.1002/vms3.912
5. Castillo UG, Komatsu A, Martínez ML, Menjívar J, Núñez MJ, Uekusa Y, Narukawa Y, Kiuchi F and Nakajima-Shimada J: Anti-trypanosomal screening of Salvadoran flora. Journal Natural Medicine 2022; 76: 259–267. https://doi.org/10.1007/s11418-021-01562-6
6. Castillo UG, Uekusa Y, Nishimura T, Kiuchi F, Martínez ML, Menjívar J, Nakajima-Shimada J, Núñez MJ and Kikuchi H: Anti-trypanosomal lignans isolated from Salvadoran Peperomia pseudopereskiifolia. Journal of Natural Products 2024; 87: 1067–1074. https://doi.org/10.1021/acs.jnatprod.4c00022
7. Amala AR and Joseph SM: Anticancer potential of Annona genus: A detailed review. Journal of the Indian Chemical Society 2021; 98(12): 100231. https://doi.org/https://doi.org/10.1016/j.jics.2021.100231
8. Moussa AY, Siddiqui SA, Elhawary EA, Guo K, Anwar S and Xu B: Phytochemical constituents, bioactivities and applications of custard apple (Annona squamosa L.): A narrative review. Food Chemistry 2024; 459: 140363. https://doi.org/https://doi.org/10.1016/j.foodchem.2024.140363
9. Al Kazman BS, Harnett M and Hanrahan JR: Traditional uses, phytochemistry and pharmacological activities of Annonacae. Molecules 2022; 27(11): 3462. https://doi.org/10.3390/molecules27113462
10. Soto-Vásquez MR, Alvarado-García PA, Osorio EH, Tallini LR and Bastida J: Antileishmanial activity of Clinanthus milagroanthus S. Leiva & Meerow (Amaryllidaceae) collected in Peru. Plants2023; 12(2): 322. https://doi.org/10.3390/plants12020322
11. Delgado-Paredes GE, Delgado-Rojas PR and Rojas-Idrogo C: Potential of the flora of Peru emphasizing in the Asteraceae family against Trypanosoma cruzi. Revista Cubana de Medicina Tropical 2024;76. http://scielo.sld.cu/scielo.php?script=sci_arttext&pid=S0375-07602024000100005&lng=es&tlng=pt
12. Rocha GN da SAO, Dutra LM, Lorenzo VP and Almeida JRG da S: Phytochemicals and biological properties of Annona coriacea Mart. (Annonaceae): A systematic review from 1971 to 2020. Chemico-Biological Interactions 2021; 336: 109390. https://doi.org/https://doi.org/10.1016/j.cbi.2021.109390
13. Shahin Nekoe, F, Khamesipour F, Habtemariam S, de SW, Mohammadi Pour P and Hossein SR: The anti-trypanosoma activities of medicinal plants: A systematic review of the literature. Veterinary Medicine and Science 2022; 8(6): 2738–2772. https://doi.org/10.1002/vms3.912
14. Gogineni V, Nael MA, León F, Núñez MJ and Cutler SJ: Computationally aided stereochemical assignment of undescribed bisabolenes from Calea urticifolia. Phytochemistry 2019; 157:145–150. https://doi.org/https://doi.org/10.1016/j.phytochem.2018.10.022
15. Kamaraj C, Ragavendran C, Kumar RCS, Ali A, Khan SU, Mashwani Z ur-R, Luna-Arias JP and Pedroza JPR: Antiparasitic potential of Asteraceae plants: A comprehensive review on therapeutic and mechanistic aspects for biocompatible drug discovery. Phytomedicine Plus 2022; 2(4): 100377. https://doi.org/10.1016/j.phyplu.2022.100377
16. Chaurasiya ND, Gogineni V, Elokely KM, León F, Núñez MJ, Klein ML, Walker LA, Cutler SJ and Tekwani BL: Isolation of acacetin from Calea urticifolia with inhibitory properties against Human Monoamine Oxidase-A and -B. Journal of Natural Products 2016; 79:2538–2544. https://doi.org/10.1021/acs.jnatprod.6b00440
17. Amaral P, Costa FV, Antunes AR, Kautz J, Citadini-Zanette V, Dévéhat FLL, Barlow J and DalBóS: The genus Calea L.: A review of isolated compounds and biological activities. Journal of Medical Plants Research 2017; 11:518–537. https://doi.org/10.5897/jmpr2017.6412
18. Mijangos-Ramos IF, Zapata-Estrella HE, Ruiz-Vargas JA, Escalante-Erosa F, Gómez-Ojeda N, García-Sosa K, Cechinel-Filho V, Meira-Quintão NL and Peña-Rodríguez LM: Bioactive dicaffeoylquinic acid derivatives from the root extract of Calea urticifolia. Revista Brasileira de Farmacognosia 2018; 28:339–343. https://doi.org/https://doi.org/10.1016/j.bjp.2018.01.010
19. Cardoso T, Souza R de J, da Silva FA and Biavatti MW: The genus Calea L.: A review on traditional uses, phytochemistry, and biological activities. Phytotherapy Research 2018; 32: 769–795. https://doi.org/10.1002/ptr.6010
20. Lima TC, Souza RJ, Moraes MH, Matos SS, Almeida FHO, Steindel M and Biavatti MW: Isolation and characterization of sesquiterpene lactones from Calea uniflora Less. and their leishmanicidal and trypanocidal activities. Química Nova 2021; 44(6): 696–699. https://doi.org/10.21577/0100-4042.20170728
21. Naik N, Kaushal RS, Upadhyay TK, Kahrizi D, Al-Najjar MA, Khan MS and Siddiqui S: Role of natural plant extracts for potential antileishmanial targets-In-depth review of the molecular mechanism. Cellular and Molecular Biology 2022; 68(10): 117–123. https://doi.org/10.14715/cmb/2022.68.10.19
22. Lima TC, Souza RJ, Morales MH, Matos SS, Almeida FHO, Steindel M and Biavatti MW: Isolation and characterization of sesquiterpene lactones from Calea uniflora less. and their leishmanicidal and trypanocidal activities. Quimica Nova 2021; 44(6): 696–699. https://doi.org/10.21577/0100-4042.20170728
23. Babu NJ, Ambika K and Rao GN: Genus Vernonia Mini Review. International Journal of Research and Review 2023; 10(11): 325–327. https://doi.org/10.52403/ijrr.20231138
24. Mishra N, Gupta E, Singh P, Soni S and Noor U: Insight on Vernonia plant for its pharmacological properties: A review. Recent Advances in Food Nutrition & Agriculture 2023; 14(2): 84–93. https://doi.org/10.2174/2212798412666230330164954
25. Moraes Neto RN, Setúbal RFB, Higino TMM, Brelaz-de-Castro MCA, Nascimento da Silva LC and Aliança ASDS: Asteraceae plants as sources of compounds against Leishmaniasis and Chagas disease. Frontiers in Pharmacology 2019; 10:477. https://doi.org/10.3389/fphar.2019.00477
26. Peixoto JF, Ramos YJ, de Lima Moreira D, Alves CR and Folcalves-Oliveira LF: Potential of Piper spp. as a source of new compounds for the leishmaniases treatment. Parasitology Research 2021; 120: 2731–2747. https://doi.org/10.1007/s00436-021-07199-4
27. Mbadiko C, Bongo G, Ngbolua KTN, Ngombe N, Kapepula P, Yandju MC, Mpiana P and Mbemba T: Uses, phytochemistry and biological activity of Piper genus: A review. Journal of Medicinal Herbs 2023; 14(1): 1–17.
28. Mesa-Vanegas AM, Naranjo-Gómez EJ, Cardona F, Atehortúa-Garcés L and Blair-Trujillo S: Quantitative standardization of pharmacologically active components from antiplasmodial plant Solanum nudum Dunal (wild and in-vitro). Boletin Latinoamericano y del Caribe de Plantas Medicinales y Aromaticas 2022; 21(1): 41–50. https://doi.org/10.37360/BLACPMA.22.21.1.02
29. Gaia AM, Yamaguchi LF, Guerrero-Perilla C and Kato MJ: Ontogenetic changes in the chemical profiles of Piper species. Plants 2021; 10(6): 1085.
30. Armijos C, Ramírez J and Vidari G: Poorly investigated Ecuadorian medicinal plants. Plants 2022; 11(12): 1590. https://doi.org/10.3390/plants11121590
31. Salleh WMNHW and Ab Ghani N: Mini review on botany, traditional uses, phytochemistry and biological activities of Piper amalago (Piperaceae). Malaysian Journal of Chemistry 2022; 24(4): 201–208.
32. dos Santos VLP, Rodrigues ICG, Berté R, Vijayasankar Raman, Messias-Reason IJ and Budel JM: Review of Piper species growing in the Brazilian State of Paraná with emphasis on the vegetative anatomy and biological activities. Botanical Review 2021; 87: 23–54. https://doi.org/10.1007/s12229-020-09239-7
33. Carvalho FA, de Moraes NV, Crotti AEM, Crevelin EJ and Dos Santos AG: Casearia essential oil: An updated review on the chemistry and pharmacological activities. Chemical Biodiversity 2023; 20:e202300492. https://doi.org/10.1002/cbdv.202300492
34. Syafni N, Faleschini MT, Garifulina A, Danton O, Gupta MP, Hering S and Hamburger M: Clerodane diterpenes from Casearia corymbosa as allosteric GABA A receptor modulators. Journal of Natural Products 2022; 85(5): 1201–1210. https://doi.org/10.1021/acs.jnatprod.1c00840
35. Martínez-Casares RM, Hernández-Vázquez L, Mandujano A, Sánchez-Pérez L, Pérez-Gutiérrez S and Pérez-Ramos J: Anti-inflammatory and cytotoxic activities of clerodane-type diterpenes. Molecules 2023; 28(12): 4744. https://doi.org/10.3390/molecules28124744
36. Syafni N, Faleschini MT, Garifulina A, Danton O, Gupta MP, Hering S and Hamburger M: Clerodane diterpenes from Casearia corymbosa as allosteric GABAA receptor modulators. Journal of Natural Products 2022; 85:1201–1210. https://doi.org/10.1021/acs.jnatprod.1c00840
37. Barbosa H, Thevenard F, Quero Reimão J, Tempone AG, Honorio KM and Lago JHG: The potential of secondary metabolites from plants as drugs or leads against Trypanosoma cruzi An update from 2012 to 2022. Current Topics in Medicinal Chemistry 2023; 23(3): 159–213. https://doi.org/10.2174/1568026623666221212111514
38. Bezerra CWC, de Medeiros RMT, Rivero BRC, Dantas AFM and Amaral, FRC: Plantas tóxicas para rumiantes e equídeos da microrregião do Cariri Cearense. Ciência Rural, Santa Maria 2012; 42: 1070-1076. https://doi.org/10.1590/S0103-84782012000600020
39. Paniagua-Zambrana NY, Bussmann RW, Echeverría J and Romero C: Solanum albidum Dunal, Solanum americanum Mill., Solanum fragile Wedd., Solanum herba-bona Reiche, Solanum mammosum L., Solanum marginatum L., Solanum nigrum L., Solanum nitidum Ruiz & Pav., Solanum nudum Dunal, Solanaceae. In: Paniagua-zambrana, N., Bussmann, R. (eds) Ethnobotany of the Andes. Ethnobotany of Mountain Regions. Springer, Cham 2020. https://doi.org/10.1007/978-3-319-77093-2_270-1
40. Mahajan VD and Shaikh HS: Solanum nigrum A potential medicinal herb. Research Journal of Science and Technology 2023; 15(1): 27–34. https://doi.org/10.52711/2349-2988.2023.00006
41. Mesa-Vanegas AM, Naranjo-Gómez EJ, Cardona F, Atehortúa-Garcés L, Blair-Trujillo S: Quantitative standardization of pharmacologically active components from Solanum nudum Dunal. Boletin Latinoamericano y Del Caribe de Plantas Medicinales y Aromaticas 2022; 21(1): 41–50.
42. Hassan AA, Khalid HE, Abdalla AH, Mukhtar MM, Osman WJ and Efferth T: Antileishmanial activities of medicinal herbs and phytochemicals in-vitro and in-vivo: An update for the years 2015 to 2021. Molecules 2022; 27(21): 7579. https://doi.org/10.3390/molecules27217579
43. Braguini WL, Pires NV and Alves BB: Phytochemical analysis, antioxidant properties, and brine shrimp lethality of unripe fruits of Solanum viarum. Journal of Young Pharmacists 2018; 10(2): 159–163. https://doi.org/10.5530/jyp.2018.10.36
    

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    Castillo UG, Alas K, Mejía M, Cerén G, Castro-Godoy WD, Guerrero RM, Menjívar J, Martínez ML, Arias CE, Nakajima-Shimada J and Núñez MJ: Remarkable anti-Trypanosoma cruzi activity in selected Salvadoran plant species. Int J Pharm Sci & Res 2025; 16(5): 1308-17. doi: 10.13040/IJPSR.0975-8232.16(5).1308-17.

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