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Free (epi) catechin, quercetin, (epi) gallocatechin, flavonol glycosides and condensed tannins were identified according to their molecular mass, characteristic product ions and retention times in extracts obtained from leaves and branches of Maytenus ilicifolia (Congorosa) by mass spectrometry. The in vitro anthelmintic activity against cattle gastrointestinal nematodes of Congorosa extract was determined using the Egg Hatch Inhibition Assay. Additionally, commercial quercetin, gallocatechin and epicatechin were evaluated. Although total phenolics, total tannins and condensed tannins contents were lower in branches extract than in leaves extract, the EC50 were 0.065 mg/mL and 0.890 mg/mL for branches and leaves extract, respectively. Moreover, the use of polyvinylpyrrolidone as a blocking agent of tannins, did not change significantly the EC50 for branches extract, but significantly changed for leaves extract. Quercetin and gallocatechin EC50 values were in the range 0.03–0.05 mg/mL and epicatechin showed 100% inhibition of the egg hatching process at 0.004 mg/mL. [ABSTRACT FROM AUTHOR]

An immunoadjuvant preparation (named Fraction B) was obtained from the aqueous extract of Quillaja brasiliensis leaves, and further fractionated by consecutive separations with silica flash MPLC and reverse phase HPLC. Two compounds were isolated, and their structures elucidated using a combination of NMR spectroscopy and mass spectrometry. One of these compounds is a previously undescribed triterpene saponin (Qb1), which is an isomer of QS-21, the unique adjuvant saponin employed in human vaccines. The other compound is a triterpene saponin previously isolated from Quillaja saponaria bark, known as S13. The structure of Qb1 consists of a quillaic acid residue substituted with a β-d-Galp-(1→2)-[β-d-Xylp-(1→3)]-β-d-GlcpA trisaccharide at C3, and a β-d-Xylp-(1→4)-α-l-Rhap-(1→2)-[α-l-Arap-(1→3)]-β-d-Fucp moiety at C28. The oligosaccharide at C28 was further substituted at O4 of the fucosyl residue with an acyl group capped with a β-d-Xylp residue. [ABSTRACT FROM AUTHOR]

Introduction: Quillaja brasiliensis (St. A. ‐Hil. & Tul) Mart (Quillajaceae) is a species native to South America, which is rich in saponins. Saponins are used in different industries, so there is a constant demand for this type of compound. Based on the wide range of applications for the saponins found in this species, notably as immunoadjuvants, we conducted a comprehensive study of this tree and its saponins. Objective: The purpose of this work is to complete the characterisation of the immunoadjuvant saponin fraction from Q. brasiliensis leaves and further study the saponin fraction obtained from Q. brasiliensis bark. Methodology: Saponin fractions were studied using mass spectrometry in combination with classical methods of monosaccharide and methylation analysis. We performed direct infusion and liquid chromatography/electrospray ionisation ion trap multiple‐stage mass spectrometry (DI‐ESI‐IT‐MSn and LC‐ESI‐IT‐MS2). Results: Seventy‐five saponins, 21 from leaves and 54 from bark, were tentatively identified according to their molecular mass, fragmentation pattern and chromatographic behaviour. This work represents the first investigation of saponins from the bark of Q. brasiliensis and some of them presented new structural motifs not previously reported in the genus Quillaja. Conclusion: The efficiency and selectivity of the data dependent LC‐MS2 method allowed the rapid profiling of saponins from Q. brasiliensis. The results of the monosaccharide and methylation analysis performed in saponins from Q. brasiliensis fractions and Q. saponaria Molina (Quillajaceae) fraction gives further support to the structures proposed according to the mass spectral data, validating the strategy used in the present work. Quillaja brasiliensis is a species native to South America, which presents immunoadjuvant saponins. The purpose of this work is to characterise these saponins from fractions of leaves and bark by using mass spectrometry in combination with classical methods of monosaccharide and methylation analysis. We performed direct infusion and liquid chromatography/electrospray ionisation ion trap multiple‐stage mass spectrometry. Seventy‐five saponins were tentatively identified according to their molecular mass, fragmentation information and chromatographic behaviour: 21 from leaves and 54 from bark. [ABSTRACT FROM AUTHOR]

The sesquiterpene lactones xanthanodiene, 4-epi-xanthanol, 4-epi-isoxanthanol, and 4-epi-xanthinin, as well as the xanthanolide derivative 4-oxo-bedfordia acid were isolated from the chloroform extracts of roots and flowers of Xanthium cavanillesii Schouw. The identities of these compounds were corroborated through comparison of their spectroscopic data, including IR, MS, and 1H and 13C NMR assignments, with literature reports. In addition, the structural characterization of 4-oxo-bedfordia acid was revisited and a comprehensive spectroscopic study of the compound is presented. This is to our knowledge the first phytochemical investigation of the roots of X. cavanillesii, and of flowers in the whole Xanthium genus. [ABSTRACT FROM AUTHOR]

Objective: The genus Xanthium L., of the Asteraceae Dum. family, (tribe Heliantheae) comprises 30 species of cosmopolitan distribution, many of which, as X. spinosum and X. strumarium are used as medicinal plants. This genus has been the object of numerous phytochemical investigations being sesquiterpene lactones with guaiane or secoguaiane frameworks the main secondary metabolites. Several sesquiterpene lactones have been demonstrated to have antimicrobial activity, in particular against Gram+ bacteria and in Uruguay the infusion of Xanthium cavanillesii Show (common name "Abrojo" or "Abrojo grande") which grows wild, is used as antiseptic in popular medicine. In this work we present the results of the antibacterial analysis of several extracts, fractions and pure compounds from X. cavanillesii against both sensitive and resistant strains of Staphylococcus aureus. Materials and Methods: Compounds were isolated from X. cavanillesii aerial parts by several chromatographic and spectroscopic methods antimicrobial analysis were performed according to Clinical and Laboratory Standards Institute guidelines. Results: The minimum inhibitory concentration (MIC) found were high for the sensitive 6538p strain when compared with common antibiotics. For the resistant strains, the pure compounds activity clearly outperformed the antibiotics, especially in the case of the multiresistant 700,699 strain with MICs of 31, 236 and 356 μg/mL for the Xanthium compounds, gentamicin and oxacillin respectively. [ABSTRACT FROM AUTHOR]

Development of new antimicrobial compounds against different microorganisms is becoming critically important, as infectious diseases are still one of the leading causes of death in the world. The pharmaceutical industry is searching for new lead compounds with novel chemical structures to overcome the increasing resistance to known antibiotics. Plants can be a useful source of these lead compounds. Xanthium cavanillesii Schouw, Asteraceae, grows wild in Uruguay and its infusion is used in traditional medicine as a skin antiseptic. We have previously reported studies on the antimicrobial activity of several extracts of X. cavanillesii against different microorganisms. In this work, we present the isolation and structural elucidation by spectroscopical methods of a sesquiterpene lactone with a new xanthanolide derived skeleton. [ABSTRACT FROM AUTHOR]

Quillaja saponaria Molina represents the main source of saponins for industrial applications. Q. saponaria triterpenoids have been studied for more than four decades and their relevance is due to their biological activities, especially as a vaccine adjuvant and immunostimulant, which have led to important research in the field of vaccine development. These saponins, alone or incorporated into immunostimulating complexes (ISCOMs), are able to modulate immunity by increasing antigen uptake, stimulating cytotoxic T lymphocyte production (Th1) and cytokines (Th2) in response to different antigens. Furthermore, antiviral, antifungal, antibacterial, antiparasitic, and antitumor activities are also reported as important biological properties of Quillaja triterpenoids. Recently, other saponins from Q. brasiliensis (A. St.-Hill. & Tul.) Mart. were successfully tested and showed similar chemical and biological properties to those of Q. saponaria barks. The aim of this manuscript is to summarize the current advances in phytochemical and pharmacological knowledge of saponins from Quillaja plants, including the particular chemical characteristics of these triterpenoids. The potential applications of Quillaja saponins to stimulate further drug discovery research will be provided. [ABSTRACT FROM AUTHOR]

• Jatropha peiranoi grows in arid northern area of Monte Desert Biome in Argentina. • The colour of tegument showed a great variability given by the time of harvest. • The endosperm is rich in oleosomes with a high content of linoleic acid, (75%). • Esterase and lipase activities were detected in the byproduct cake. • In vitro clonal propagation protocols employing nodal explants were developed. Jatropha peiranoi grows in the arid northern area of Monte Desert Biome in Argentina. This plant is adapted to low temperatures during the winter season. This study deeply describes the seed structure and oil characteristics as well as the clonal in vitro propagation of the plant in order to evaluate its potential as a new energetic crop. Wild seeds were harvested from Santa Maria Valley during the reproductive season. The color of its tegument showed a great variability given by the time of harvest and degree of ripening of the fruits. The endosperm was rich in oleosomes and protein bodies. The seed oil yield obtained was 33%. The lipid profile was linoleic acid (75%), oleic acid (15.6%), stearic acid (4%) and palmitic acid (5.9%). The oil was stable to the high temperatures, with a boiling point at 380 °C, without decomposition even at 400 °C. Lipolytic enzymes were detected in the seed-cake, with values of 84.5 U/g and 46.7 U/g for lipase and esterase, respectively. A protocol for in vitro clonal propagation was achieved employing nodal explants. For the shoot induction and proliferation, a concentration of BAP up to 0.2 mg/L caused an increase in the number of axillary shoots per explant. The optimum IBA concentration for the rooting was 0.2 mg/L. The plantlets were successfully acclimatized in soil. Currently, the field performance of clones with desirable traits is being evaluated. This work contributes to Jatropha species knowledge since Jatropha peiranoi is one of the adapted species to extreme environmental conditions that differs from other members of the genus. [ABSTRACT FROM AUTHOR]

Free (epi) catechin, quercetin, (epi) gallocatechin, flavonol glycosides and condensed tannins were identified according to their molecular mass, characteristic product ions and retention times in extracts obtained from leaves and branches of Maytenus ilicifolia (Congorosa) by mass spectrometry. The in vitro anthelmintic activity against cattle gastrointestinal nematodes of Congorosa extract was determined using the Egg Hatch Inhibition Assay. Additionally, commercial quercetin, gallocatechin and epicatechin were evaluated. Although total phenolics, total tannins and condensed tannins contents were lower in branches extract than in leaves extract, the EC 50 were 0.065 mg/mL and 0.890 mg/mL for branches and leaves extract, respectively. Moreover, the use of polyvinylpyrrolidone as a blocking agent of tannins, did not change significantly the EC 50 for branches extract, but significantly changed for leaves extract. Quercetin and gallocatechin EC 50 values were in the range 0.03-0.05 mg/mL and epicatechin showed 100% inhibition of the egg hatching process at 0.004 mg/mL.

The effect on color of the initial pH employed in dulce de leche (DL) production was evaluated through physicochemical and spectroscopical characterization of the melanoidins formed in the process. Melanoidins originated at pH values of 6.5, 7.0, and 7.5, and they were released by the enzymatic hydrolysis of the protein backbone and purified by gel filtration. They showed a significant degree of polydispersity, in general, with molecular weights (MWs) below 1,800 Da. DL produced at a higher pH released melanoidins with higher average MW after the enzymatic hydrolysis. They also presented darker colors (dE * ab, C * ), more closely resembling those typical of the commercial product. Analysis of the fractions isolated by gel filtration using HPLC-DAD and multinuclear NMR showed an heterogeneous and complex composition. Even though structurally related, the 1H NMR spectra of melanoidins showed a higher degree of aromaticity at higher pH values. In conclusion, the pH employed in DL production affects the amount and structure of the colored products originated by MR reactions, and thus the color of the final product., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Rodríguez, Lema, Bessio, Moyna, Olivaro, Ferreira and Panizzolo.)