The Use of Medicinal Plants in the Riverside Community of the Mazagão River in the Brazilian Amazon, Amapá, Brazil: Ethnobotanical and Ethnopharmacological Studies

Demographic, social, and clinical aspects associated with access to COVID-19 health care in Pará province, Brazilian Amazon

Internal social disparities in the Brazilian Amazon became more evident during the COVID-19 pandemic. The aim of this work was to examine the demographic, social and clinical factors associated with access to COVID-19 health care in Pará Province in the Brazilian Amazon. This was an observational, cross-sectional, analytical study using a quantitative method through an online survey conducted from May to August 2023. People were eligible to participate if they were current residents of Pará, 18-years-old or older, with self-reported diagnoses of COVID-19 through rapid or laboratory tests. Participants completed an electronic survey was developed using Research Electronic Data Capture (REDCap) software-The adapted questionnaire "COVID-19 Global Clinical Platform: Case Report Form for Post-COVID Condition". Questions focused on access to COVID-19 treatment, demographic characteristics, COVID-19 vaccine and clinical characteristics. Respondent-driven sampling was applied to recruit participants. Multiple logistic regression was utilized to identify the associated factors. Overall, a total of 638 participants were included. The average age was 31.1 years. Access to COVID-19 health care was 68.65% (438/638). The participants most likely to access health care were those with moderate or severe COVID-19 (p = 0.000; OR: 19.8) and females (p = 0.001; OR: 1.99). Moreover, participants who used homemade tea or herbal medicines were less likely to receive health care for COVID-19 in health services (p = 0.002; OR: 0.54). Ensuring access to healthcare is important in a pandemic scenario.

Cosmetic application of the stem-bark extract of Bertholletia excelsa H.B.K

OBJECTIVE

The Amazon has a rich biodiversity where many different plant species can be found. This diversity is an important source of bioactive substances, mainly due to the different structural components of their phytometabolites. Research for natural products is a strategy for the development of new agents in therapeutic applications, especially cosmetic applications, that have better pharmacological potential. Within this perspective, the objective of the study was to investigate the cosmetic application (anti-aging potential) of the stem-bark extract of Bertholletia excelsa H.B.K - (SBEBE), popularly known as the Brazil nut tree, here called SBEBE, a noble plant species of the Amazon that is rich in selenium.

METHODS

Enzymatic, glycation, proliferation, cell-healing, collagen quantification, toxicity and genotoxicity assays were used.

RESULTS

Among the enzymes involved in the extracellular matrix of the skin, SBEBE was able to inhibit only elastase (62.67 ± 3.75) when compared to the standard sivelestat (89.04 ± 0.53), and the extract was also able to inhibit both the oxidative and the non-oxidative pathway. When cell toxicity in fibroblasts (MRC-5) and keratinocytes (HACAT) was evaluated, SBEBE did not present toxicity in 24 h of incubation. After this period, the extract showed average cytotoxicity in 48 and 72 h, but not enough to reach the concentration of 50% of MRC-5 fibroblasts. In the trypan blue assay, the extract promoted fibroblast proliferation in 24, 48 and 72 h of incubation, which was evaluated through exponential cell growth, with emphasis mainly on the lowest concentration with results higher than the standard. When the cell healing capacity was evaluated, in 48 h of exposure to fibroblast, SBEBE was able to induce a cell carpet (cell film) in the cell monolayer scratch assay.

CONCLUSIONS

SBEBE stimulated collagen production at all concentrations tested. In the alkaline comet assay, at the lowest concentration, the extract did not induce DNA damage when compared to the reference drug doxorubicin. This study proved that SBEBE extract can be considered an ally in the treatment of skin anti-ageing as a possible biotechnological, phytocosmetic product.

Pentaclethra macroloba: A Review of the Biological, Pharmacological, Phytochemical, Cosmetic, Nutritional and Biofuel Potential of this Amazonian Plant

Pracaxi (Penthaclethra macroloba (Willd.) Kuntze) is an Amazonian plant, traditionally used by the native population to treat health disorders such as inflammation, erysipelas, wound healing, muscle pain, ear pain, diarrhea, snake and insect bites as well as for cancer treatment. Other common uses include using the oil for frying, skin and hair beautification, and as an alternative source of energy. This review is focused on highlighting its taxonomy, occurrence and botanical origins, popular uses, pharmacology and biological activities, cytotoxicity, biofuel activity and phytochemistry in order to explore future therapeutic use and other applications. Pracaxi contains triterpene saponins, sterols, tannins, oleanolic acid, unsaturated fatty acids and long-chain fatty acids, with a high behenic acid value, which may serve for incorporation into drug delivery systems as well for the development of new drugs. These components are correlated with its anti-inflammatory, antimicrobial, healing, anti-hemolytic, anti-hemorrhagic, antiophidic, and larvicidal activities against Aedes aegypti and Helicorverpa zea, which ratify the popular/traditional uses. The species is nitrogen fixing; it is easy to propagate in floodplains and the terra firma, and it can be used for the reforestation of degraded areas. Additionally, the oil extracted from the seeds can leverage the bioeconomy of the region based on sustainable exploration.

Biological Potential of Products Obtained from Palm Trees of the Genus Syagrus

Medicinal plants have been used for centuries by communities worldwide, as they have diverse biological properties and are effective against numerous diseases. The genus Syagrus stands out for its versatility and for so many activities presented by these palm trees, mainly due to its rich chemical and fatty acid compositions. The genus has antibacterial potential, has antibiofilm, antiparasitic, antioxidant, prebiotic, antiulcerogenic, anticholinesterase, and hypoglycemic activities, and can produce biodiesel, amid others. Among all species, Syagrus coronata and Syagrus romanzoffiana stand out, presenting the greatest number of activities and applications. The secondary metabolites obtained from these palm trees present high activity even in low concentrations and can be used against infections and chronic diseases. Furthermore, these plants have been used in some communities for years and have presented healing properties, especially in inflammatory processes. Therefore, the Syagrus genus proves to be promising, which shows a lot of therapeutic potential.

Pharmacognostic Evaluation of Ten Species of Medicinal Importance of Cecropia: Current Knowledge and Therapeutic Perspectives

This work covers a systematic review of literature about the genus Cecropia from 1978 to 2020, emphasizing the analysis of 10 of the most relevant species and their associated biological activities. Cecropia is a neotropical genus, which comprises about 61 native species in the American continent where it is known to be part of the traditional medicine of numerous countries. Secondary metabolites described for this genus showed an elevated structural and functional diversity, where polyphenols have been the most abundant. Based on this diversity, Cecropia phytochemicals represent an important source of potential therapeutic agents yet to be exploited. This review also highlights the effectiveness of combining chemometrics and ultra-performance liquid chromatography-tandem mass spectrometry as a novel approach to successfully single out Cecropia species phytochemicals. While the medicinal use of Cecropia species is officially recognized in National Pharmacopoeias and Formularies of several Latin American countries, it is important to recognize that these phytomedicines are complex mixtures requiring a thorough understanding of their chemical composition and their correlation with biological activities to guarantee their quality, safety, and efficacy.

Toxicity evaluation of Eleutherine plicata Herb. extracts and possible cell death mechanism

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Ethanol extract of Eleutherine plicata showed low in vitro and in vivo cytotoxic potential.

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The dichloromethane fraction was cytotoxic to HepG2 and caused DNA. However, no toxicity was observed in vivo.

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Isoeleutherin caused DNA damage by the comet method and activated caspase-8 in the in silico study.

Eleutherine plicata has been shown to be a promising medicinal plant, and its activity has been associated with naphthoquinones. The present study aimed at evaluating the cytotoxicity, genotoxicity, and oral toxicity of the ethanol extract (EEEp), dichloromethane fraction (FDMEp) of E. plicata, and isoeleutherin. For the cytotoxicity evaluation, the viability test (MTT) was used. Genotoxicity was accessed through the Comet assay (alkaline version), acute and subacute oral toxicities were also evaluated. The antioxidant capacity of the samples in the wells where the cells were treated with E. plicata was evaluated. Furthermore, the participation of caspase-8 in the possible mechanism of action of isoeleutherin, eleutherin, and eleutherol was also investigated through a docking study. FDMEp and isoeleutherin were cytotoxic, with higher rates of DNA fragmentation observed for FDMEp and isoeleutherin, and all samples displayed higher antioxidant potential than the control. In the acute oral toxicity test, EEEp, FDMEp, and isoeleutherin did not cause significant clinical changes. In the subacute toxicity assay, EEEp and FDMEp also did not cause clinical, hematological, or biochemical changes. The three compounds bound similarly to caspase-8. Despite the results of cytotoxicity, in vitro studies demonstrated that the use of EEEp appears to be safe and cell death may involve its binding to caspase-8.

Pharmacological Extracts and Molecules from Virola Species: Traditional Uses, Phytochemistry, and Biological Activity

Virola is the largest genus of Myristicaceae in America, comprising about 60 species of medium-sized trees geographically spread from Mexico to southern Brazil. The plant species of this genus have been widely used in folk medicine for the treatment of several ailments, such as rheumatic pain, bronchial asthma, tumors in the joints, intestinal worms, halitosis, ulcers, and multiple infections, due to their pharmacological activity. This review presents an updated and comprehensive summary of Virola species, particularly their ethnomedicinal uses, phytochemistry, and biological activity, to support the safe medicinal use of plant extracts and provide guidance for future research. The Virola spp.'s ethnopharmacology, including in the treatment of stomach pain and gastric ulcers, as well as antimicrobial and tryponosomicidal activities, is attributable to the presence of a myriad of phytoconstituents, such as flavonoids, tannins, phenolic acids, lignans, arylalkanones, and sitosterol. Hence, such species yield potential leads or molecular scaffolds for the development of new pharmaceutical formulations, encouraging the elucidation of not-yet-understood action mechanisms and ascertaining their safety for humans.

Nano-emulsification of Aeollanthus suaveolens Mart. Ex Spreng essential oil modifies its neuroeffects?

Oil in water nano-emulsions are drug delivery systems constituted by liquid lipophilic nano-droplets dispersed through the external aqueous phase, often reaching the kinetic stability with surfactant as stabilizers. Essential oils can be the oily phase or the source of bioactive compounds. In this study, the essential oil of Aeollanthus suaveolens-a plant used in folk medicine due to its psychopharmacological effects-was used for preparation of fine nano-emulsions by a low-energy titrating method. Monodisperse small nano-droplets (ca. 70 nm; PdI 0.200) were assembled by using blends of non-ionic surfactants, indicating modulation on surfactant system lead to altering the physical property. In a separate set of experiments, we investigated the role of this modulation on biological properties of the optimal nano-emulsion. The zebrafish embryos were more susceptible to the nano-emulsion than the bulk essential oil, showing the improved bioactivity due to nano-sizing. Therefore, adult zebrafish was treated, and paralysis was observed in the groups treated with the nano-emulsion, being this finding in accordance with hypnosis. At the same essential oil dose, another behavior was observed, suggesting that expected dose-dependent effects associated to sedative-hypnotics can be achieved by nano-sizing of psychoactive essential oils. This paper contributes to the state-of-art drug delivery systems by opening perspectives for novel sedative-hypnotics nano-emulsified essentials oils that can reach hypnotic effects at considerably lower dose, when compared with bulk materials, being useful for further completed dose-response studies.Graphical abstract.

Natural Products as Sources of Antimalarial Drugs: Ethnobotanical and Ethnopharmacological Studies

MATERIALS AND METHODS

For this study, relevant information was procured from the inhabitants via a structured questionnaire to procure the general knowledge of antimalarial medicinal plants. Results and Discussion. A total of 90 interviewees (44 men and 46 women) were involved in this survey. A total of 59 medicinal species were identified, which were dispersed in 33 families (Asteraceae (6), Apocynaceae (5), Anacardiaceae, Annonaceae, Fabaceae, Malvaceae, Meliaceae, Poaceae, and Rubiaceae (3 each), Phyllanthaceae (2)) totaling 49% of the cited species. The most cited plants are Azadirachta indica (42), Mangifera indica (38), Carica papaya (28), Cymbopogon citratus (27), Cassia fistula (15), Morinda lucida (14), Anacardium occidentale and Vernonia amygdalina (13 each), Helianthus annuus (11), Enantia chlorantha (10), and Moringa oleifera (9) A total of 105 citations were recorded for the plant parts used (leaf (46), bark (17), fruits (9), root (9), latex (11), stem (11), and inflorescence (2)) while decoction (59%), maceration (25%), infusion (9%), and exudation (7%) were the methods of preparation. Use Values (UVs) of 0.47 to 0.11 were recorded for the frequently used antimalarial plants. The Efficiency Levels (ELs) of 11 different medicinal plants stated by the respondents were Azadirachta indica, Cassia fistula and Morinda lucida (12), Chromolaena odorata (10), Mangifera indica, Enantia chlorantha and Helianthus annuus (8), Cymbopogon citratus (7), Gossypium arboretum (4), Landolphia dulcis (3), and Aloe vera (2) Cocos nucifera, Curcuma longa, Forkia biglobosa, and Musa acuminate are mentioned for the first time in the study area with little or no reported antiplasmodial activities.

CONCLUSION

The study appraised the commonly used antimalarial plants in the study areas. Therefore, commitment to scientifically explore the bioactive compounds, antimalarial potential and toxicological profile of these plants is inevitable as they could lead to novel natural products for effective malaria therapy.