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Background: Athenaea fasciculata, a Brazilian native species from the Solanaceae family, is recognized as a promising source of bioactive withanolides, particularly Aurelianolide A and B, which exhibit significant antitumoral activities. Despite its potential, research on the chemical constituents of this species remains limited. This study aimed to dereplicate extracts and partitions of A. fasciculata to streamline the discovery of bioactive withanolides. Methods: Using ultra-high-performance liquid chromatography–tandem mass spectrometry (UHPLC-MS/MS), various extracts—including n-hexane, methanol, and ethanol—were analyzed, and their mass spectrometry data were processed through the GNPS platform for the generation of molecular networking. The results indicated that crude extracts displayed comparable cytotoxicity against Jurkat cells, by treatment at 150 µg/mL, while alcoholic extracts achieved approximately 80% inhibition of K562 cells and K562-Lucena 1 at the same concentration. Notably, the dichloromethane partition exhibited the highest cytotoxicity across leukemia cell lines, particularly against Jurkat cells (IC50 = 14.34 µg/mL). A total of 22 compounds were annotated by manual inspection and different libraries, with six of them demonstrating significant cytotoxic effects. Conclusions: This research underscores the therapeutic potential of A. fasciculata and highlights the effectiveness of integrating advanced analytical methods in drug discovery, paving the way for further exploration of its bioactive compounds. [ABSTRACT FROM AUTHOR]

Traditional medicine shows several treatment protocols for COVID-19 based on natural products, revealing its potential as a possible source of anti-SARS-CoV-2 agents. Ampelozizyphus amazonicus is popularly used in the Brazilian Amazon as a fortifier and tonic, and recently, it has been reported to relieve COVID-19 symptoms. This work aimed to investigate the antiviral potential of A. amazonicus, focusing on the inhibition of spike and ACE2 receptor interaction, a key step in successful infection. Although saponins are the major compounds of this plant and often reported as its active principles, a polyphenol-rich extract was the best inhibitor of the spike and ACE2 interaction. Chemical characterization of A. amazonicus bark extracts by LC-DAD-APCI-MS/MS before and after clean-up steps for polyphenol removal showed that the latter play an essential role in maintaining this activity. The effects of the extracts on viral replication were also assessed, and all samples (aqueous and ethanol extracts) demonstrated in vitro activity, inhibiting viral titers in the supernatant of Calu-3 cells after 24 hpi. By acting both in the SARS-CoV-2 cell entry process and its replication, A. amazonicus bark extracts stand out as a multitarget agent, highlighting the species as a promising candidate in the development of anti-SARS-CoV-2 drugs. [ABSTRACT FROM AUTHOR]

The Swartzia species are commonly known as bloodwood due to the red exudate released from the stem after injury. This exudate has aroused great interest, and an integrative study is essential to describe it in detail. Thus, this work aimed to identify the red exudate's secreting-site in S. flaemingii and S. langsdorffii, and determine if it is a latex or a resin. Samples of the stem bark and the secondary xylem were prepared for histological analysis. Fresh exudates were dissolved in deuterated methanol and analyzed by 1H-NMR; other samples were resuspended in MeOH:H2O (9:1), partitioned with organic solvents and analyzed by direct infusion mass spectrometry. Total phenolic and total flavonoid contents were determined spectrophotometrically, and antioxidant capacity was determined using ferric reducing antioxidant power assay. The results showed that the exudate is a red latex produced by articulated laticifers located among the phloem cells. The latex is composed of sucrose, catechin glucosides, chlorophyll derivatives, and hederagenin-type saponins. Both samples of S. flaemingii and S. langsdorffii presented high amounts of phenolics and flavonoids, as well as a strong antioxidant capacity. The anatomical study showed that the secreting-site of the Swartzia red exudates were laticifers. This finding allows us to exclude other substances such as resin or oleoresin, generally produced by secretory cavities or ducts. Furthermore, since laticifers are rare in Fabaceae, this finding is significant, and represents an essential taxonomic feature. The showy red color is due to the large amounts of flavonoids. This latex probably has a protective role against microorganisms and photodamage. The bioactive potential of this exudate inspires further studies, which may boost the economic importance of Swartzia. [ABSTRACT FROM AUTHOR]

Siparuna glycycarpa occurs in the Amazon region, and some species of this genus are used in Brazilian folk medicine. A recent study showed the inhibitory effect of this species against influenza A(H1N1)pdm09 virus, and in order to acquire active fractions, a polar solvent system n-butanol-methanol-water (9:1:10, v/v) was selected and used for bioassay-guided fractionation of n-butanol extract by centrifugal partition chromatography (CPC). The upper phase was used as stationary phase and the lower phase as mobile (descending mode). Among the collected fractions, the ones coded SGA, SGC, SGD, and SGO showed the highest antiviral inhibition levels (above 74%) at 100 µg·mL−1 after 24 h of infection. The bioactive fractions chemical profiles were investigated by LC-HRMS/MS data in positive and negative ionization modes exploring the Global Natural Products Social Molecular Networking (GNPS) platform to build a molecular network. Benzylisoquinoline alkaloids were annotated in the fractions coded SGA, SGC, and SGD collected during elution step. Aporphine alkaloids, O-glycosylated flavonoids, and dihydrochalcones in SGO were acquired with the change of mobile phase from lower aqueous to upper organic. Benzylisoquinolinic and aporphine alkaloids as well as glycosylated flavonoids were annotated in the most bioactive fractions suggesting this group of compounds as responsible for antiviral activity. [ABSTRACT FROM AUTHOR]

Ampelozizyphus amazonicus Ducke is a medicinal plant used in the Amazon region to prepare a drink with tonic, immunomodulatory and adaptogenic properties. Due to the growing interest in dietary supplements with these properties and, to provide a new functional ingredient, barks from A. amazonicus were extracted. The extract was spray dried without drying adjuvants, resulting in a powder (SARF), which was characterized by its physico-chemical properties and proximate, mineral and saponin contents. The SARF saponins were characterized by ultra-high-performance liquid chromatography/high resolution accurate mass spectrometry (HPLC-HRMS n ) analysis. The SARF particles tended to have a spherical shape and a unimodal size distribution. The particles also had good rehydration characteristics and high saponin content (33%). The effect of SARF on antibody production was investigated, and we found that SARF increased the basal levels of anti-ovalbumin, anti-LPS and anti-dextran IgM antibodies, and the anti-dextran IgG antibodies in unimmunized mice. No increase in antibody titers was observed after SARF treatment in immunized mice. These results suggest that SARF could be an interesting new functional ingredient for food applications or pharmaceutical products. [ABSTRACT FROM AUTHOR]

In Latin American Traditional Medicine, the use of Burseraceae oleoresins for headache relief is widespread. In the quilombola (maroon) communities of the municipality of Oriximiná, Pará State, Brazil, Burseraceae oleoresins are burned as incenses to treat headache; an effect attained by inhaling the smokes. This study was designed to investigate the scientific rationale behind the use of Burseraceae pitch oleoresin smokes on headache by identifying its chemical constituents and discussing whether they could be beneficial for headache treatment. Two samples of pitch oleoresins were purchased from Amazonian public markets; one of them marketed as " breu preto " (black pitch), and the other as " breu branco " (white pitch). The smoke headspaces produced upon burning these oleoresins were collected and analysed by GC-MS. For comparative purposes, the triterpenoid fingerprints of the oleoresins' dichloromethane extracts and profiles of the essential oils were also obtained by GC-MS — and GC-FID, in the case of the essential oils. A total of 32 compounds were detected in black and white pitch oleoresin smokes. All smoke headspaces of the pitch oleoresins shared the presence of volatile terpenoids (e.g., α-terpineol) and triterpenoids (e.g., α-amyrin, β-amyrin, α-amyrone, and β-amyrone). These compounds were also present in the crude resins and could potentially be responsible for anti-inflammatory, antinociceptive and analgesic effects on headache. The pharmacological data on the terpenoids detected in the Burseraceae pitch smokes strongly support their traditional use for headache, but their actual effects upon inhalation have yet to be determined. [Display omitted] [ABSTRACT FROM AUTHOR]

Hyptis monticola Mart. ex Benth. (Lamiaceae) is an endemic species of altitude regions of Brazil. From the leaves of this plant, two 5,6-dihydro- α -pyrones, named monticolides A and B, have been reported as cytotoxic agents against different tumor cell lines. The isolation by high-speed countercurrent chromatography in combination with recycling preparative high-performance liquid chromatography of the undescribed monticolides C-F is presented. These compounds corresponded to a series of related monticolide derivatives differing from each other by the number of acyl substituents. Their characterization by mass spectrometry and nuclear magnetic resonance is also presented, in conjunction with an evidence by a simple chemical correlation for their absolute stereochemistry. The distribution of these chemical markers in extracts of flowers, leaves and branches collected in different seasons by electrospray ionization ion trap mass spectrometry in positive mode was analyzed. Multivariate data analyses indicated that seasonality affects monticolide concentrations in different organs of the aerial parts. Monticolides A-F seem to be present as the original markers of the analyzed plant. However, mono-, di- and triacetylated monticolides can undergo acid-catalyzed transesterifications and their natural yields estimated were affected during the isolation procedures. [Display omitted] • Monticolides C-F were isolated as undescribed 6-heptyl-5,6-dihydro-2 H -pyran-2-ones. • Distribution of monticolides A-F in different plant organs were analyzed by UHPLC-ESI- MS/MS. • Multivariate data analyses indicated that seasonality affects monticolide concentrations. • Monticolides A-F seems to be present as original makers of the analyzed plant material. • Mono-, di- and triacetylated montecolides can undergo acid-catalyzed transesterifications. [ABSTRACT FROM AUTHOR]

In the quilombola communities of the municipality of Oriximiná (Pará State, Brazil), Protium spp. (Burseraceae) oleoresins are distinguished in black and white pitch. White pitch oleoresins may be superior to black pitch in terms of quality, but the criteria used for their differentiation are fairly subjective. This study was designed to provide a scientific rationale for the traditional differentiation of black and white pitch oleoresins based on their non-volatile fraction. Black and white pitch oleoresin samples collected in quilombola territories in Oriximiná were analysed by GC-EI-MS and UPLC-APCI-MS. The feasibility of EI and APCI mass spectrometry-based pattern recognition methods PLS-DA and Random Forest Analysis (RFA) for black and white pitch oleoresins differentiation was demonstrated. The UPLC-APCI-MS method allowed the separation of 43 triterpenoids. Assessment of the triterpenoid fingerprints by GC-EI-MS led to the tentative identification of ursa-9(11),12-dien-3-ol as a potential marker for black pitch oleoresins. PLS-DA and RFA applied to the APCI-MS and EI-MS data gave good models for black and white pitch oleoresins classification. The most important ions for the classifications of black pitch oleoresins by APCI-MS/PLS-DA and APCI-MS/RFA likely represented triterpenoid acids. The triterpenoid pattern differs between black and white pitch oleoresins. The characteristic presence of ursa-9(11),12-dien-3-ol and triterpenoids acids in black pitch oleoresins, along with other field observations, suggest that black pitch oleoresins are actually aged white pitch oleoresins. Image 1 • A new term, "chemoethnotaxonomy", is being proposed. • Analysis of black and white pitch oleoresins by UPLC-APCI-MS and GC-EI-MS. • Construction of PLS-DA and Random Forest Analysis models for pitch classification using MS data. • Identification of ursa-9(11),12-dien-3-ol as a potential chemical marker for black pitch oleoresins. [ABSTRACT FROM AUTHOR]