LC–MS characterization, anti-kinetoplastide and cytotoxic activities of natural products from Eugenia jambolana Lam. and Eugenia uniflora

Influence of Major Polyphenols on the Anti-Candida Activity of Eugenia uniflora Leaves: Isolation, LC-ESI-HRMS/MS Characterization and In Vitro Evaluation

The content of chemical constituents in Eugenia uniflora leaf extracts correlates positively with biological activities. The experimental objective was to carry out the phytochemical screening and purification of the major polyphenols from the leaves of E. uniflora. In addition, the anti-Candida activity of the hydroalcoholic extract, fraction, subfractions and polyphenols purified were evaluated. After partitioning of the extract with ethyl acetate, the fractions were chromatographed on Sephadex® LH-20 gel followed by RP-flash chromatography and monitored by TLC and RP-HPLC. The samples were characterized by mass spectrometry (LC-ESI-QTOF-MS2) and subjected to the microdilution method in 96-well plates against strains of C. albicans, C. auris, and C. glabrata. Myricitrin (93.89%; w/w; m/z 463.0876), gallic acid (99.9%; w/w; m/z 169.0142), and ellagic acid (94.2%; w/w; m/z 300.9988) were recovered. The polyphenolic fraction (62.67% (w/w) myricitrin) and the ellagic fraction (67.86% (w/w) ellagic acid) showed the best antifungal performance (MIC between 62.50 and 500 μg/mL), suggesting an association between the majority constituents and the antifungal response of E. uniflora derivatives. However, there is a clear dependence on the presence of the complex chemical mixture. In conclusion, chromatographic strategies were effectively employed to recover the major polyphenols from the leaves of the species.

Applications of Essential Oils and Plant Extracts in Different Industries

Essential oils (EOs) and plant extracts are sources of beneficial chemical compounds that have potential applications in medicine, food, cosmetics, and the agriculture industry. Plant medicines were the only option for preventing and treating mankind's diseases for centuries. Therefore, plant products are fundamental sources for producing natural drugs. The extraction of the EOs is the first important step in preparing these compounds. Modern extraction methods are effective in the efficient development of these compounds. Moreover, the compounds extracted from plants have natural antimicrobial activity against many spoilage and disease-causing bacteria. Also, the use of plant compounds in cosmetics and hygiene products, in addition to their high marketability, has been helpful for many beauty problems. On the other hand, the agricultural industry has recently shifted more from conventional production systems to authenticated organic production systems, as consumers prefer products without any pesticide and herbicide residues, and certified organic products command higher prices. EOs and plant extracts can be utilized as ingredients in plant antipathogens, biopesticides, and bioherbicides for the agricultural sector. Considering the need and the importance of using EOs and plant extracts in pharmaceutical and other industries, this review paper outlines the different aspects of the applications of these compounds in various sectors.

A new N-oxide benzylisoquinoline alkaloid isolated from the leaves of atemoya (Annona cherimola × Annona squamosa)

Phytochemical investigation of the atemoya aerial parts was carried out by LC-MS-IT and cytotoxic activities were evaluated as well. These results led to the identification of a new N-oxide alkaloid (dehydroanomuricine-N-oxide) and eight other alkaloids: scoulerine, reticuline, isocorydine, norisocorydine, asimilobine, nornuciferine, anonaine, and liriodenine. The new alkaloid dehydroanomuricine-N-oxide and anomuricine were also isolated. The structures of these compounds were determined by spectroscopic and spectrometric techniques. The cytotoxic capacity of crude methanolic extract and the alkaloidal fraction were evaluated, showing moderate cytotoxicity. The isolation and identification of these alkaloids are an important contribution to the chemotaxonomy of the genus Annona and the Annonaceae family.

Antidiabetic effects of Syzygium cumini leaves: A non-hemolytic plant with potential against process of oxidation, glycation, inflammation and digestive enzymes catalysis

ETHNOPHARMACOLOGICAL RELEVANCE

Plant materials are commonly used in traditional medicine in order to treat various diseases such as Diabetes mellitus. Some plants, such as Syzygium cumini, have the capability to act controlling oxidative stress and protein glycation besides their potential to decrease hyperglycemia and hyperlipidemia by the inhibition of the catalysis of digestive enzymes. The aim of this study was to evaluate the antioxidant and antiglicant activity of S. cumini leaves fractions, their capacity to inhibit hydrolases and lipase enzymes, as well as the cytotoxicity effects against erythrocytes and comparate these results with isolate quercetin flavonoid.

MATERIAL AND METHODS

Ethnobotanical researches, carried out by academic studies at the Federal University of Uberlandia, led us to choose S. cumini as a potential plant for treatment of Diabetes mellitus. Fractions from ethanolic extract of S. cumini (hexane/Hex, dichloromethane/DCM, ethyl acetate/EtOAc, n-butanol/ButOH and water/H₂O) were used to evaluate their antioxidant (DPPH, ORAC and FRAP) and antiglycant (BSA/fructose, BSA/methylglyoxal and Arginine/Methylglyoxal) activity as well as the inhibitory potential against α-amylase, α-glucosidase and lipase. In addition, identification of the main bioactive compounds of S. cuimini leaves by HPLC-ESIMS/MS analysis was carried out.

RESULTS

Our results indicate that all fractions, for exception Hex, present noteworthy antioxidant activity, mainly in EtOAc and ButOH fractions (FRAP 1154.49 ± 67.37 and 1178.27 ± 21.26 μmol trolox eq g^-1, respectively; ORAC 1224.63 ± 58.16 and 1313.53 ± 85.23 μmol trolox eq g^-1, respectively; DPPH IC₅₀ 15.7 ± 2.4 and 23.5 ± 2.7 μg mL^-1, respectively). Regarding the antiglycant activity (BSA/fructose and Arginine/Methylglyoxal models), all fraction, for exception Hex, presented inhibition higher than 85%. All fractions were capable to inhibit 100% of α-amylase and the fractions DCM, EtOAc and ButOH inhibited α-glucosidase more than 50%. Regarding the lipase assay, DCM and Hex had the best activity (31.5 ± 14.3 and 44.3 ± 4.5 μg mL^-1, respectively). Various biomolecules known as potent antioxidants were identified in these fractions, such as quercetin, kaempferol, luteolin and (Epi)catechin.

CONCLUSION

S. cumini fractions and quercetin presented promising antioxidant and antiglycation properties as well as the ability to inhibit digestive enzymes. This study presents new biological activities not yet described for S. cumini which provide new possibilities for further studies in order to assess the antidiabetic potential of S. cumini fractions especially EtOAc and ButOH.

Composition, antioxidant capacity and cytotoxic activity of Eugenia uniflora L. chemotype-oils from the Amazon

ETHNOPHARMACOLOGICAL RELEVANCE

Oils and extracts of Eugenia uniflora have been reported as antimicrobial, antifungal, antinociceptive, antiprotozoal, antioxidant and cytotoxic.

AIM OF THE STUDY

The oils of five specimens (E1 to E5) that occur in the Brazilian Amazon were extracted, analyzed for their chemical composition, and submitted to antioxidant and cytotoxic assays.

MATERIAL AND METHODS

Oils were hydrodistilled, analyzed by GC and GC-MS, and submitted to PCA and HCA analyses. The antioxidant activity of the oils was evaluated by the DPPH radical scavenging and the β-carotene/linoleic acid assays. Antiproliferative effects of the oils and curzerene were tested against colon (HCT-116), gastric (AGP-01), and melanoma (SKMEL-19) human cancer cell lines and a normal human fibroblast cell line (MRC-5), using MTT assay.

RESULTS

Oxygenated sesquiterpenes and sesquiterpene hydrocarbons such as curzerene, selina-1,3,7(11)-trien-2-one, selina-1,3,7(11)-trien-2-one epoxide, germacrene B, caryophyllene oxide, and (E)-caryophyllene were predominant in the oils. PCA and HCA analyses classified the oils samples into four chemotypes. TEAC values of chemotype II (E3 oil, 228.3 ± 19.2 mg TE/mL) and chemotype III (E4 oil, 217.0 ± 23.3 mg TE/mL) displayed significant antioxidant activities. The oils E2 and E4 showed cytotoxic activity against all cell lines tested HCT-116 (IC₅₀ E2:16.26 μg/mL; IC₅₀ E4:9.28 μg/mL), AGP-01, (IC₅₀ E2:12.60 μg/mL; IC₅₀ E4:8.73 μg/mL), SKMEL-19 (IC₅₀ E2:12.20 μg/mL; IC₅₀ E4:15.42 μg/mL), and MRC-5 (IC₅₀ E2:10.27 μg/mL; IC₅₀ E4:14.95 μg/mL). Curzerene showed the more significant activity against melanoma cells (SKMEL-19, IC₅₀:5.17 μM), induced apoptosis at 5.0 μM and 10.0 μM compared to DMSO, exhibiting a decrease in the cell migration at 5.0 μM and 10.0 μM, after 30 h of treatment.

CONCLUSION

The curzerene chemotype oil and E. uniflora oils can be indicated as drug candidates for anticancer activity of the lung, colon, stomach, and melanoma, with a real prospect to their subsequent phytotherapeutic development.

Psidium guajava bioactive product chemical analysis and heavy metal toxicity reduction

The present study had as its objective to verify the Psidium guajava var. Pomifera L. chelating, antioxidant and cytoprotective effects against mercury and aluminum. The ethanolic extract, tannic and flavonoid fractions were subjected to LC-MS analysis. The Ferric Reducing Antioxidant Power (FRAP) and ferric ion reduction demonstrated a present antioxidant activity. The fungicidal and bactericidal activity of these metals were established. After determining the sub-allelopathic doses, germination tests using Lactuca sativa were performed. Quercetin and its derivatives were the main compounds identified in the extract and the fractions. Mercury chloride significantly reduced the bactericidal effect of the flavonoid fraction (p < 0.001). None of the fractions were cytoprotective against mercury or aluminum in the fungal model assays. Using a sub-allelopathic concentration (64 μg/mL), the ethanolic extract, flavonoid and tannic fractions were found to be cytoprotective against aluminum for radicles, however only the tannic fraction was cytoprotective for caulicles. These data suggest that natural P. guajava products are promising cytoprotective compound sources. This activity may be related to the antioxidant effect of secondary metabolites, mainly flavonoids. Our results point to a potential for environmental intervention product and technique development aimed at mitigating contamination by toxic metals such as mercury and aluminum.