Investigation of phytochemical composition and bioactivity evaluation of extracts from Myrsine umbellata Mart.

The objective of the study was to carry out phytochemical prospection through colorimetric tests to determine the groups of secondary metabolites and also to determine the total content of phenolic compounds (TPC) present in plant extracts methanol (ME), ethyl acetate (EAE), hexane (HE) and dichloromethane (DE) from the leaves of Myrsine umbellata, as well as to investigate the antimicrobial activity against twelve standard ATCC strains by the broth microdilution technique; the antioxidant potential by the DPPH method and the ABTS method and the antibiofilm potential on the biofilm biomass of standard bacteria by the crystal violet technique and tetrazolium salt reduction (MTT) assay. Phytochemical prospection detected the presence of saponins, steroids, alkaloids, anthocyanins, anthocyanidins, flavonoids, and tannins. The results of the quantitative phytochemical estimation revealed a higher content of total phenolics in DE (280.24 ± 0.037 µM GAE g ext. -1) followed by ME (159.01 ± 0.031 µM GAE g ext. -1). The ME showed the best biological activities when compared to the other extracts tested. We observed antimicrobial activity against Gram-positive Staphylococcus epidermidis strain (MIC 3.12 and MBC 6.25), antioxidant percentage of 92.58% against the DPPH radical and 420.31 µM Trolox g ext. -1 against the ABTS radical, finally showed antibiofilm action against Gram-positive strain Staphylococcus aureus, with eradication of the biomass in 92.58%. The results suggest that EM from M. umbellata represents an alternative source of plant bioactives for the development of natura products.

Proteomic and physiological signatures of altitude adaptation in a Myrsine coriacea population under common garden conditions.

Plants exhibit phenotypic plasticity in response to environmental variations, which can lead to stable genetic and physiological adaptations if exposure to specific conditions is prolonged. Myrsine coriacea demonstrates this through its ability to thrive in diverse environments. The objective of the article is to investigate potential differences in protein accumulation and physiological responses of M. coriacea by cultivating plants from seeds collected from four populations at different altitudes in a common garden experiment. Additionally, we aim to evaluate whether these differences exhibit genetic fixation. Through integrated physiological and proteomic analyses, we identified 170 differentially accumulated proteins and observed significant physiological differences among the populations. The high-altitude population (POP1) exhibited a unique proteomic profile with significant down-regulation of proteins involved in carbon fixation and energy metabolism, suggesting a potential reduction in photosynthetic efficiency. Physiological analyses showed lower leaf nitrogen content, net CO2 assimilation rate, specific leaf area, and relative growth rate in stem height for POP1, alongside higher leaf carbon isotopic composition (δ13C) and leaf carbon (C) content. These findings provide insight into the complex interplay between proteomic and physiological adaptations in M. coriacea and underscore the importance of local adaptations. SIGNIFICANCE: We investigate the adaptive responses of M. coriacea, a shrub with a broad phenotypic range, by cultivating plants from seeds collected at four different altitudes in a common garden experiment. These findings provide insight into the complex interplay between proteomic and physiological adaptations in M. coriacea and underscore the importance of local adaptations in the face of climate change. This study contributes to advancing our understanding of the influence of altitude-specific selection pressures on the molecular biology and physiology of plants in natural populations. Our findings provide valuable insights that enhance our ability to predict and comprehend how plants respond to climate change.

Determinação da atividade antitirosinase e antioxidante de Myrsine coriacea (Sw. ) R. Br. ex Roem. & Schult. (Primulaceae) / Determination of the antityrosinase and antioxidant activity of Myrsine coriacea (Sw. ) R. Br. ex Roem. & Schult. (Primulaceae)

myrsine coriacea (Sw.) R. Br. ex Roem. & Schult. (Primulaceae) conhecida popularmente como capororoquinha ou capororoca, é amplamente distribuída nas regiões sul e sudeste do Brasil. As espécies desse gênero apresentam um potencial antioxidante e anti-inflamatório, que pode ser acessado na busca de novos ativos para o tratamento de desordens pigmentares da pele. Desta forma, este trabalho teve como objetivos avaliar o potencial antitirosinase e antioxidante de extratos e frações de M. coriacea e identificar os possíveis compostos responsáveis por essas atividades. Foram realizados ensaios para avaliar o potencial antioxidante das amostras através do método do DPPH, enquanto a capacidade hipopigmentante das amostras foi avaliado pela inibição da enzima tirosinase. Como complemento, foram determinados os teores de compostos fenólicos totais e flavonoides através dos métodos colorimétricos empregando o reagente Folin-Ciocalteau e AlCl3. Adicionalmente, os extratos de M. coriacea tiveram avaliados seus potenciais citotóxicos utilizando diferentes linhagens tumorais humanas. O perfil fitoquímico de M. coriacea foi analisado por cromatografia a gás acoplada com espectrometria de massas (CG-EM) e cromatografia em camada delgada (CCD) com padrões. Nessas análises foram identificados 34 compostos, sendo o ácido palmítico e o palmitato de etila os compostos majoritários nas amostras de M. coriacea. O extrato bruto das folhas apresentou o maior teor de fenólicos totais, enquanto a fração de acetato de etila das folhas teve o maior teor de flavonoides. Contudo, o extrato bruto dos frutos apresentou a melhor atividade antioxidante de todas as amostras analisadas, apresentando também a melhor atividade antitirosinase. Dentre os compostos anotados, mandenol, ácido -linoleico e o linolenato de etila foram os compostos considerados como possíveis inibidores da tirosinase, com boa interação molecular com a enzima nas análises de ancoragem molecular in silico. Das amostras analisadas com relação a inibição de crescimento frente as células tumorais, a amostra da fração de clorofórmio das folhas foi a que apresentou potencial antitumoral frente as células de adenocarcinoma de cólon (HCT116)

myrsine coriacea (Sw.) R. Br. ex Roem. & Schult. (Primulaceae) popularly known as capororoquinha or capororoca, is widely distributed in southern and southeastern Brazil. Myrsine species have an antioxidant and anti-inflammatory potential, which can be accessed in the search for new actives for the treatment of skin pigmentation disorders. Thus, this work aimed to evaluate the antityrosinase and antioxidant potential from extracts and fractions of M. coriacea and to identify the probable compounds responsible for these activities. Assays were performed to evaluate the antioxidant potential of the samples using the DPPH method, while the hypopigmentation capacity of the samples was evaluated by the tyrosinase inhibition. As a complement, the amounts of total phenolic compounds and flavonoids were determined through colorimetric methods using the Folin-Ciocalteau reagent and AlCl3. Additionally, M. coriacea extracts had their cytotoxic potential evaluated using different human tumor cell lines. M. coriacea phytochemical profile was obtained by gas chromatography coupled with mass spectrometry (GC-MS) and thin layer chromatography (TLC) with standards. In these analyses, 34 compounds were identified, with palmitic acid and ethyl palmitate as the major compounds in M. coriacea samples. The leaf crude extract presented the highest total phenolics contents, while the leaf ethyl acetate fraction had the highest flavonoid amounts. However, the fruit crude extract showed the best antioxidant and antityrosinase activities of all analyzed samples. Among the annotated compounds, mandenol, -linoleic acid and ethyl linolenate were the compounds considered as putative tyrosinase inhibitors, presenting good molecular interaction with the enzyme active site in the in silico molecular docking analysis. The leaf chloroform fraction was the only sample that showed an antitumor potential against colon adenocarcinoma cells (HCT116)

Arbuscular mycorrhizal fungi activity in the rhizosphere of tree seedlings subjected to residual herbicides / Atividade de fungos micorrízicos arbusculares na rizosfera de mudas de árvores submetidas a herbicidas residuais

Trees occurring on the margins of agricultural areas can mitigate damage from residual herbicides. Rhizospheric microbial activity associated with trees is one of the main remedial capacity indicators. The objective of this study was to evaluate the rhizospheric microbiological activity in tree species subjected to the herbicides atrazine and sulfentrazone via the rhizosphere. The experiment was designed in four blocks and a 6 × 3 factorial scheme. The first factor consisted of six tree species from Brazil and the second of atrazine, sulfentrazone, and water solutions. Four herbicide applications were performed via irrigation. The total dry mass of the plants, mycorrhizal colonization, number of spores, basal respiration of the rhizospheric soil, and survival rate of bioindicator plants after phytoremediation were determined. Trichilia hirta had higher biomass when treated with atrazine and sulfentrazone. Herbicides decreased the microbial activity in Triplaris americana and did not affect the microbiological indicators of Myrsine gardneriana, Schizolobium parahyba, and Toona ciliata. Fewer bioindicator plants survived in soil with Triplaris americana and sulfentrazone. Microbiological indicators were influenced in different ways between species by the presence of herbicides in the rhizosphere.

As árvores que ocorrem nas margens das áreas agrícolas podem mitigar os danos dos herbicidas residuais. A atividade microbiana rizosférica associada às árvores é um dos principais indicadores de capacidade corretiva. O objetivo deste trabalho foi avaliar a atividade microbiológica rizosférica em espécies arbóreas submetidas aos herbicidas atrazina e sulfentrazone via rizosfera. O experimento foi estruturado em quatro blocos e esquema fatorial 6 × 3. O primeiro fator consistiu em seis espécies de árvores do Brasil e o segundo em soluções de atrazine, sulfentrazone e água. Quatro aplicações de herbicidas foram realizadas via irrigação. Foram determinados a massa seca total das plantas, colonização micorrízica, número de esporos, respiração basal do solo rizosférico e taxa de sobrevivência de plantas bioindicadoras após fitorremediação. Trichilia hirta apresentou maior biomassa quando tratada com atrazina e sulfentrazone. Os herbicidas diminuíram a atividade microbiana em Triplaris americana e não afetaram os indicadores microbiológicos de Myrsine gardneriana, Schizolobium parahyba e Toona ciliata. Menos plantas bioindicadoras sobreviveram no solo com Triplaris americana e sulfentrazone. Os indicadores microbiológicos foram influenciados de formas distintas entre as espécies pela presença dos herbicidas na rizosfera.

Green Synthesis and Characterization of Silver Nanoparticles Using Myrsine africana Leaf Extract for Their Antibacterial, Antioxidant and Phytotoxic Activities.

Nanotechnology is the study and control of materials at length scales between 1 and 100 nanometers (nm), where incredible phenomena enable new applications. It affects all aspects of human life and is the most active research topic in modern materials science. Among the various metallic nanoparticles used in biomedical applications, silver nanoparticles (AgNPs) are among the most important and interesting nanomaterials. The aim of this study was to synthesize AgNPs from the leaf extract of Myrsine africana to investigate their antibacterial, antioxidant, and phytotoxic activities. When the leaf extract was treated with AgNO3, the color of the reaction solution changed from light brown to dark brown, indicating the formation of AgNPs. The UV-visible spectrum showed an absorption peak at 438 nm, confirming the synthesis of AgNPs. Scanning electron microscopy (SEM) showed that the AgNPs were spherical and oval with an average size of 28.32 nm. Fourier transform infrared spectroscopy confirms the presence of bio-compound functional groups on the surface of the AgNPs. The crystalline nature of the AgNPs was confirmed by XRD pattern. These biosynthesized AgNPs showed pronounced antibacterial activity against Gram-positive and Gram-negative bacteria, with higher inhibitory activity against Escherichia coli. At 40 µg/mL AgNPs, the highest antioxidant activity was obtained, which was 57.7% and an IC50 value of 77.56 µg/mL. A significant positive effect was observed on all morphological parameters when AgNPs were applied to wheat seedlings under constant external conditions at the different concentrations. The present study provides a cost-effective and environmentally friendly method for the synthesis of AgNPs, which can be effectively used in the field of therapeutics, as antimicrobial and diagnostic agents, and as plant growth promoters.

Phytochemical prospection and evaluation of antimicrobial, antioxidant and antibiofilm activities of extracts and essential oil from leaves of Myrsine umbellata Mart. (Primulaceae).

The species Myrsine umbellata is a native plant of Brazil, whose barks are traditionally used in herbal medicine to treat liver disorders and combat leprosy. Therefore, the aim of the study was to identify the phytochemical prospection of ethanolic (EE) and acetonic (EA) extracts by colorimetric tests and by gas chromatography coupled to mass spectrometry (GC-MS) of the essential oil (EO) of M. umbellata leaves; evaluate the antimicrobial activity in front of standard ATCC strains by the broth microdilution technique; the antioxidant potential by DPPH reduction method and antibiofilm action by crystal violet assay and cell viability was determined using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) based on optical density. Phytochemical prospection of EE and EA detected the presence of free steroids, alkaloids, flavonoids (flavones, flavononoids, flavonols and xanthons) and tannins in both extracts (EE and EA) and saponins only in EE. In EO, the majority compounds identified were elixene, caryophyllene (E), spatulenol, d-Cadinene and aromadendrene. EA showed antimicrobial activity with MIC and MBC/MFC values ranging from 3.12 to 100 mg.mL-1, highlighting its efficiency on the Gram-positive strain S. epidermidis. EE showed antimicrobial potential in the range of 3.12 to 200 mg.mL-1, and the Gram-negative E. coli strain was the most susceptible. However, OE showed bacteriostatic potential against S. Typhimurium, S. Abaetetuba, P. aeruginosa, and S. epidermidis strains. The ability to sequester free radicals was evident in EA extract with antioxidant activity of 89.55% and in EE with 63.05%. The antibiofilm potential was observed in EE extract which eradicated the mature biofilm biomass of all tested bacteria with high activity (50% to 84.28%) and EO also showed antibiofilm effect on mature biofilm of UEL enteroaggregative E. coli, S. aureus and S. Enteritidis strains with biomass reduction percentage of 63.74%, 68.04% and 86.19%, respectively. These results indicate the potential of M. umbellata extracts and as a source of plant bioactivity for the development of new alternative strategies for the control of planktonic or biofilm-resistant microorganisms.

Lack of coordination between stomatal and vein traits provides functional benefits to the dioecious tropical tree Myrsine coriacea.

Climate change will affect the distribution of many tropical plant species. However, the understanding of how dioecious tropical species cope with different environmental conditions is still limited. To address this issue, we investigated how secondary trait attributes in populations of the dioecious tropical tree Myrsine coriacea change along an altitudinal gradient. Eighty individual plants (40 male and 40 female) were selected among seven natural populations. Leaf variation in morphological and stomatal traits, and carbon and nitrogen isotopic compositions were analyzed. Female plants had greater isotopic leaf carbon composition (δ13 C) and nitrogen content than male plants, increasing their carboxylation capacity. Plants of both sexes had smaller stomata, greater water-use efficiency (greater δ13 C), and greater nitrogen isotopic composition (δ15 N) at higher altitudes. They also showed lower δ15 N and had greater carbon: nitrogen ratios at lower altitudes. There was a lack of coordination between stomatal and vein traits, which was compensated for by variation in specific leaf areas. This mechanism was essential for increasing plant performance under the limiting conditions found by the species at higher altitudes.

Myrsinoic acid B from Myrsine coriacea reverses depressive-like behavior and brain oxidative stress in streptozotocin-diabetic rats.

AIMS: Major depressive disorder (MDD) affects approximately 322 million people worldwide and is a common comorbidity in patients with diabetes mellitus (DM). A possible pathophysiological mechanism correlating both diseases is the increased oxidative stress in brain regions due to hyperglycemia. Myrsine coriacea (Primulaceae) is popularly known as "capororoca" and studies have been shown that this plant exhibits several pharmacological properties attributed to myrsinoic acid A (MAA) and B (MAB). Indeed, previous results have been shown its effects on the central nervous system, leading us to explore possible psychotropic effects. MAIN METHODS: The effects of treatment with hydroalcoholic extract of the barks from Myrsine coriacea (HEBMC, 150 mg/kg, o.g.), MAA (5 mg/kg, o.g.), and MAB (3 mg/kg, o.g.) were evaluated in streptozotocin (75 mg/kg, i.p.)-induced diabetic female rats. After 28 days of treatments, rats were submitted to the forced swim test (FST) and open field test (OFT). Also, superoxide dismutase (SOD) and catalase (CAT) activities, reduced glutathione (GSH) and lipid hydroperoxides (LOOH) levels were evaluated in the hippocampus (HIP) and prefrontal cortex (PFC) of these rats. KEY FINDINGS: The treatment with MAA or MAB increased the latency of first immobility in diabetic rats, and the HEBMC administration decreased the immobility time, and increase the climbing in FST. However, only MAB treatment reduces the immobility time, increases the climbing, and swimming in FST, and increases the crossing of diabetic animals in the OFT. Besides, this behavioral improvement promoted by MAB administration was accompanied by reducing in oxidative stress in the HIP and PFC, but not reducing hyperglycemia in diabetic rats. SIGNIFICANCE: The results suggest that MAB's antioxidant effect in the HIP of diabetic animals may be essential to its antidepressant-like effect.

Phytochemistry, antioxidant and antibacterial activities of fruit extracts of Myrsine africana L.

Myrsine africana L. a commonly consumed medicinal plant grows in forest of mountains region located at North East of Pakistan. In current study, the fruit extracts were chemically characterized and their bioactivities were determined. Higher quantity of total phenols, total flavonoids and tannins were obtained from methanolic fruit extracts. The HPLC analysis provided higher level of quercetin followed by rutin and p-coumaric acid. Whereas the GC-MS quantification had given significant level of ten saturated and unsaturated fatty acids and some of them were not reported earlier. In vitro study, lower cytotoxic behavior of fruit extracts but higher antioxidant values as well as higher zone of inhibition versus S. aureus, E. coli, K. pneumonia and B. subtilis and Mycobacterium tuberculosis were observed. The organic compounds found in fruit extracts of M. africana correlated well with its used in ethno medicines.

Experimental validation and computational modeling of anti-influenza effects of quercetin-3-O-α-L-rhamnopyranoside from indigenous south African medicinal plant Rapanea melanophloeos.

BACKGROUND: Influenza A virus (IAV) is still a major health threat. The clinical manifestations of this infection are related to immune dysregulation, which causes morbidity and mortality. The usage of traditional medication with immunomodulatory properties against influenza infection has been increased recently. Our previous study showed antiviral activity of quercetin-3-O-α-L-rhamnopyranoside (Q3R) isolated from Rapanea melanophloeos (RM) (L.) Mez (family Myrsinaceae) against H1N1 (A/PR/8/34) infection. This study aimed to confirm the wider range of immunomodulatory effect of Q3R on selective pro- and anti-inflammatory cytokines against IAV in vitro, to evaluate the effect of Q3R on apoptosis pathway in combination with H1N1, also to assess the physical interaction of Q3R with virus glycoproteins and RhoA protein using computational docking. METHODS: MDCK cells were exposed to Q3R and 100CCID50/100 µl of H1N1 in combined treatments (co-, pre- and post-penetration treatments). The treatments were tested for the cytokines evaluation at RNA and protein levels by qPCR and ELISA, respectively. In another set of treatment, apoptosis was examined by detecting RhoA GTPase protein and caspase-3 activity. Molecular docking was used as a tool for evaluation of the potential anti-influenza activity of Q3R. RESULTS: The expressions of cytokines in both genome and protein levels were significantly affected by Q3R treatment. It was shown that Q3R was much more effective against influenza when it was applied in co-penetration treatment. Q3R in combination with H1N1 increased caspase-3 activity while decreasing RhoA activation. The molecular docking results showed strong binding ability of Q3R with M2 transmembrane, Neuraminidase of 2009 pandemic H1N1, N1 and H1 of PR/8/1934 and Human RhoA proteins, with docking energy of - 10.81, - 10.47, - 9.52, - 9.24 and - 8.78 Kcal/mol, respectively. CONCLUSIONS: Quercetin-3-O-α-L-rhamnopyranoside from RM was significantly effective against influenza infection by immunomodulatory properties, affecting the apoptosis pathway and binding ability to viral receptors M2 transmembrane and Neuraminidase of 2009 pandemic H1N1 and human RhoA cellular protein. Further research will focus on detecting the detailed specific mechanism of Q3R in virus-host interactions.

Protective effect of Myrsine parvifolia plant extract against the inflammatory process induced by Bothrops jararaca snake venom.

Accidents involving snakes from the genus Bothrops sp. constitute the most important cause of snake envenomation in Brazil. The Myrsine genus has been reported to be used in folk medicine against snakebites. In this work, the phytochemical profiles and ability of extracts from Myrsine parvifolia leaves to reduce the inflammatory process (edema, vascular permeability increase and leukocyte migration) induced by Bothrops jararaca venom were investigated in vivo. Chemical compounds were identified by chromatographic and spectroscopy techniques. Total polyphenol, tannin, and flavonoid contents were determined by spectrophotometric methods. Swiss male mice received an oral administration of extracts (100 mg/kg) in different protocols. Paw edema, intraperitoneal vascular permeability and pleurisy models in mice were used to evaluate the antiophidic potential of the extracts. Paw edema was induced by subplantar injection of B. jararaca venom and quantified as the increase in paw volume. Changes in vascular permeability were assessed by measuring the amount of Evans blue dye extravasation. Leukocyte migration was assessed by total and differential counts in the pleural cavity washes. Myricetin, myricetin-3-O-ß-arabinopyranoside, quercetin and kaempferol were isolated from the ethyl acetate extract and identified as the primary compounds of the dichloromethane extract. Terpenes and fatty acids were identified in the hexane and dichloromethane extracts. The pretreated group with hydroethanolic and dichloromethane extract reduced total edema (40 and 52%, respectively), vascular permeability increase (32.4 and 32.2%, respectively) and leukocyte influx into the pleural cavity (42 and 39%, respectively), while the group treated with hexane extract showed only reduced edema (37%) induced by B. jararaca venom. The hydroethanolic extract showed better results in all of the tests performed and was also administered by the protocol of post-poisoning, showing maintenance of paw edema reduction and cell migration. These data indicate a potential anti-inflammatory activity of M. parvifolia in poisoning by B. jararaca, especially to reduce local poison effects.

In Vitro Anti/Pro-oxidant Activities of R. ferruginea Extract and Its Effect on Glioma Cell Viability: Correlation with Phenolic Compound Content and Effects on Membrane Dynamics.

Rapanea ferruginea antioxidant and antitumoral properties were not explored before in literature. This study aimed to investigate these biological activities for the R. ferruginea leaf extract and correlate them with its phenolic content and influence in biological membrane dynamics. Thus, in this study, anti/pro-oxidative properties of R. ferruginea leaf extract by in vitro DPPH and TBARS assays, with respect to the free radical reducing potential and to its activity regarding membrane free radical-induced peroxidation, respectively. Furthermore, preliminary tests related to the extract effect on in vitro glioma cell viability were also performed. In parallel, the phenolic content was detected by HPLC-DAD and included syringic and trans-cinnamic acids, quercetrin, catechin, quercetin, and gallic acid. In an attempt to correlate the biological activity of R. ferruginea extract and its effect on membrane dynamics, the molecular interaction between the extract and a liposomal model with natural-sourced phospholipids was investigated. Location and changes in vibrational, rotational, and translational lipid motions, as well as in the phase state of liposomes, induced by R. ferruginea extract, were monitored by Fourier-transform infrared spectroscopy, nuclear magnetic resonance, differential scanning calorimetry, and UV-visible spectroscopy. In its free form, the extract showed promising in vitro antioxidant properties. Free-form extract (at 1000µ g/mL) exposure reduced glioma cell in vitro viability in 40%, as evidenced by MTT tests. Pro-oxidant behavior was observed when the extract was loaded into liposomes. A 70.8% cell viability reduction was achieved with 500 µg/mL of liposome-loaded extract. The compounds of R. ferruginea extract ordered liposome interface and disorder edits a polar region. Phenolic content, as well as membrane interaction and modulation may have an important role in the oxidative and antitumoral activities of the R. ferruginea leaf extract.

Isolation of Flavonoids and Flavonoid Glycosides from Myrsine africana and Their Inhibitory Activities against Mushroom Tyrosinase.

Bioassay-guided fractionation of the methanol extract of the shoots of Myrsine africana led to the isolation of the new compound myricetin 3-O-(2″,4″-di-O-acetyl)-α-l-rhamnopyranoside (9) and 11 known compounds. The known compounds quercetin 3-O-(3″,4″-di-O-acetyl)-α-l-rhamnopyranoside (8), rutin (10), quercetin 3-O-α-l-rhamnopyranoside (11), and myricetin 3-O-α-l-rhamnopyranoside (12) are reported for the first time from the methanol extract of the shoots of M. africana. Compounds 10 and 12 showed significant inhibition of tyrosinase with 50% inhibition (IC50 values) of the enzyme at 0.13 ± 0.003 and 0.12 ± 0.002 mM, respectively, which was supported by the docking fitness scores obtained through molecular docking analysis. In addition, compounds 1-12 displayed significant antioxidant activity with IC50 values ranging 1.90 to 3.90 µM.