Globunoids A-D, undescribed bichalconoid and biflavanoids with α-glucosidase and α-amylase inhibitory activities from Knema globularia stems

A bichalconoid, globunoid A (1) and three biflavanones, globunoids B-D (2-4), previously undescribed, were isolated from the stems of Knema globularia, along with fourteen known analogues 5-18. The chemical structures of 1-4 were elucidated by the comprehensive spectroscopic analysis including UV, IR, HRESIMS, and NMR; the absolute configurations were determined based on their NOESY data, DP4+ statistical analysis, and ECD calculation. Up to now, compounds 2 and 3 represent the first 3,3″-linked biflavanone structures. Among the isolated compounds, 2, 3, and 2,3-dihydrocalodenin B (6) potently inhibited α-glucosidase and α-amylase activities, with IC50 values in the range 1.1-7.5 μM. Furthermore, the most active compound 6 was found to be a non-competitive inhibitor against these two enzymes.

Do chromium-resistant bacterial symbionts of hyperaccumulator Callitriche cophocarpa support their host in phytobial remediation of water?

Callitriche cophocarpa Sendtn. is a macrophyte widely distributed in aquatic systems of the temperate climate zone and a known hyperaccumulator of chromium. Ten pure symbiotic bacterial isolates of C. cophocarpa were obtained and identified. Three of the isolates showed the highest resistance to Cr(VI): Microbacterium sp. (Ct1), Aeromonas sp. (Ct3) and Acinetobacter sp. (Ct6). Acinetobacter sp. (Ct6) was able to survive up to a concentration of 104 mg/L (2 mM). The isolates were also able to effectively detoxify Cr(VI) by reducing it to Cr(III). We tested whether inoculation of plants with a consortium consisting of Ct1, Ct3 and Ct6 affects: (1) the phytoextraction of chromium from leachates, (2) the physiological state of plants after Cr(VI) treatment. The solutions were landfill leachates and contained 10.7 mg/L of Cr(VI) - an amount 530 times exceeding the legal limits. We influenced the plants with Cr in two steps, each lasting for 10 days, first using mature shoots and then apical ones. The highest Cr content concomitant with the highest bioconcentration factor (BCF) were found in the inoculated plants: 1274 and 119 mg/kg dry mass (d.m.), respectively. The physiological status of the plants was assessed by biometric tests and advanced chlorophyll fluorescence analyses. The photosynthetic activity of mature shoots was influenced by Cr(VI) more negatively than that of young apical shoots. The inoculation with the bacterial consortium significantly reduced the negative effect of Cr(VI) on mature organs. In some cases the inoculated mature plants exhibited photosynthetic activity that was even higher than in the control plants. The results unequivocally show a beneficial effect of C. cophocarpa inoculation with the tested isolates resulting in a significant improvement of the phytoremediation properties of this aquatic chromium hyperaccumulator.

Phytochemical evaluation and exploration of some biological activities of aqueous and ethanolic extracts of two species of the genus Plantago L

Plantago major L. and Plantago lagopus L. are cosmopolitan species, belonging to the Plantaginaceae family, used in traditional and modern medicine. In this study, a phytochemical evaluation of different aqueous and ethanolic extracts of leaves and roots of both species from the region of Beja in Tunisia was performed. Some biological activities, including antioxidant, anticancer and antibacterial were also done. LC-MS qualitative analysis revealed that the aqueous extracts of the roots of P. lagopus were richer in polyphenols, mainly flavonoids (Luteoline 7-rutinoside, Luteoline 7-rhamnoside) and hydroxycinnamic acids including caffeic acid, than the hydro-ethanolic extracts. Additionally, we identified for the first time the presence of salicylic acid in the hot aqueous extracts of roots of P. lagopus and its absence in the roots of P. major. The antioxidant activity of the extracts was assessed using cyclic voltammetry (CV), revealing that the voltammograms of leaf and root extracts from P. lagopus exhibited a higher antioxidant capacity compared to those of P. major. Antiproliferative activity, was determined against two-colon cancer cell lines, demonstrated that only the 12 h treatments with P. lagopus leaf and root aqueous and hydro-ethanolic extracts at low concentration were able to significantly reduce the colon carcinoma coli-2 (CaCo-2) cells proliferation. The antibacterial /antibiofilm activity was performed on yeast, Gram- negative and +positive bacterial strains. We demonstrated for the first time that ethanolic extracts of leaves and roots of P. lagopus have an inhibitory activity against Escherichia coli and Klebsiella pneumonia at MIC = 2 μg/mL for leaves and 4 μg/mL for roots.

Biological activities and determination of the mode of action of Tunisian Globularia alypum and Cistus monspeliensis ethanolic extracts

This study was designed to evaluate the antioxidant and antimicrobial activity of ethanolic extracts (EEs) of Cistus monspeliensis and Globularia alypum. C. monspeliensis showed the highest values of phenolic compounds. Further, it was shown that EE of C. monspeliensis displayed the highest DPPH (IC50 = 8.3 ± 1.08 mg/mL). The chemical profiles demonstrated a total of 12 and 13 phenolic compounds for C. monspeliensis and G. alypum, respectively. EEs of both plants possessed broad-spectrum antimicrobial activity when tested against Escherichia coli and Staphylococcus aureus. Treatment of studied strains with these extracts at their MICs reduced considerably the bacterial viability. The extracts did not induce total bacterial lysis, as determined by the measurement of optical density at 620 nm. Strains treated with EEs at Minimum Inhibitory Concentrations showed significant loss of tolerance to NaCl. Our results contribute to understanding the antibacterial mechanism of ethanolic extracts of the studied medicinal plants.

Metals in Callitriche cophocarpa from small rivers with various levels of pollution in SW Poland

The anthropogenic impact of metals on aquatic environments is a risk for biota, and thus their levels must be controlled. Callitriche cophocarpa Sendtn. belongs to a genus with a potential for accumulation of elevated metal levels. Thus, it may provide consolidated evidence of contamination. Therefore, the aim of this investigation was to determine Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb and Zn in this species collected together with water and bottom sediments from rivers with various levels of pollution. Of these rivers, one less polluted and one more polluted was selected for the collection of C. cophocarpa for an experiment to compare its Cu and Zn concentration potential. Both metals were supplemented at concentrations 0.01, 0.02, 0.03, 0.05, 0.08 and 0.14 mg L-1 of Cu as CuSO4 × 5H2O and 0.4, 0.6, 0,9, 1,35, 2.03 and 3.04 mg L-1 of Zn as ZnSO4 × 7H2O, and in the binary design containing (mg·L-1) 0.01Cu + 0.4Zn, 0.02Cu + 0.6Zn, 0.03Cu + 0.9Zn, 0.05Cu + 1.4Zn, 0.08Cu + 2.03 Zn and 0.14Cu + 3.04Zn. The upper concentrations of Cr, Cu, Mn and Zn in C. cophocarpa shoots from both types of rivers as well as of Ni and Pb in shoots from more polluted rivers were higher than the values typical for toxicity thresholds with no visible harmful effects, which may indicate accumulation abilities of C. cophocarpa for these metals. Both roots and shoots of C. cophocarpa may be included in the group of macroconcentrators for bottom sediments with respect to Cd, Co, Cr, Cu, Fe, Mn, Ni and Zn and deconcentrators of Pb. Greater accumulation of most metals in roots than in shoots indicates their restricted mobility and translocation by C. cophocarpa to shoots. C. cophocarpa from the less polluted river and exposed to all experimental solutions contained significantly higher levels of Cu and Zn than that from the more polluted river exposed to identical experimental solutions. The plants collected from the more polluted river influenced by surplus of metals and living under chemical stress could probably limit further accumulation by developing a resistance mechanism. Cu and Zn contents in C. cophocarpa were higher when treated with separate metals than for binary treatment both in the more and less polluted river. Such research presenting the impact of a combination of metals could be important for understanding and explaining the interactions of these elements which may influence their bioavailability in nature as well as importance in the evaluation of the risk of environmental toxicity.

Seasonal and Circadian Evaluation of the Essential Oil of Dizygostemon riparius (Plantaginaceae), a Wild Flavoring Herb from East Maranhão, Brazil

Dizygostemon riparius (Plantaginaceae) is an aromatic herbal species known as "Melosa", endemic to the Municipality of São Benedito do Rio Preto, East Maranhão state, Brazil. It has a refreshing and pleasant aroma and is used for food flavoring and controlling domestic animal parasites. This work aimed to evaluate the seasonal and circadian influence on the composition and production of essential oils (EOs) from D. riparius. The plant aerial parts were hydrodistilled, and the oils were analyzed by GC and GC/MS. The seasonal study was conducted from August 2019 to July 2020, and the circadian study in dry (November) and rainy (May) periods, at 6 am, 12 am, and 6 pm. The results showed that the medium EOs yield was 2.8 %, and the primary constituents (>2 %) were endo-fenchyl acetate (30.5-42.1 %) and endo-fenchol (31.6-37.4 %), (E)-caryophyllene (2.8-7.6 %), α-fenchene (3.3-6.5 %), p-cymene (0.7-4.5 %), and caryophyllene oxide (1.4-2.7 %). Yield and composition of EOs did not significantly correlate with the climatic parameters, but their seasonal percentages influenced their two main components due to precipitation and solar radiation environmental factors. Quantitative variability in the EOs composition during the dry and rainy seasons was observed in the circadian period. These data may be significant for the plant's economic use.

A review on the traditional uses, phytochemistry, and pharmacology of the genus Veronicastrum (Plantaginaceae)

ETHNOPHARMACOLOGICAL RELEVANCE

Veronicastrum Heist. ex Fabr. (Plantaginaceae) is a multifunctional plant in China and other parts of the continent. It has traditionally been used in the treatment of ascites, edema, blood stasis, pain relief, chronic nephritis injury, fever, cough, headache, arthritis, dysentery, rheumatism, pleural effusion, liver damage, and other disorders. Although research has confirmed that the genus Veronicastrum contain many active compounds, no review of its traditional uses, phytochemistry or pharmacology has been conducted to date.

AIM

This review aims to systematically evaluate the traditional uses, phytochemistry, and pharmacology of the genus Veronicastrum, discuss its medicinal potential, modern scientific research, and the relationship between them, and put forward some suggestions to promote further development and utilization of Veronicastrum.

MATERIALS AND METHODS

The traditional uses, phytochemical and pharmacological data related to the genus Veronicastrum from 1955 to date was compiled by surveying the ethnomedicinal books and published papers, and searching the online databases including Google Scholar, China National Knowledge Infrastructure (CNKI), Science Direct, Web of Science and World Flora Online.

RESULTS

Species of the genus Veronicastrum are widely used in folkloric medicine and some of their uses have been confirmed in modern pharmacological activities. A total of 89 chemical constituents have been isolated from the genus Veronicastrum, including flavonoids, carbohydrates, iridoids, terpenoids, phytosterols, phenolic acids, and other constituents. Among the compounds isolated, iridoids, flavonoids, and terpenoids are responsible for the biological activities of this genus with significant pharmacological activities both in vitro and in vivo. The extracts and compounds isolated from this genus have been reported to contain a wide range of pharmacological activities such as immunosuppressive, antioxidant, anti-cancer, anti-inflammatory, gastro protective, and antimicrobial activity.

CONCLUSION

The genus Veronicastrum is not only a great herbal remedy, but also has numerous bioactive chemicals with potential for new drug discovery. In the literature, phytochemical investigations have been undertaken on five species. Detailed scientific research is still needed to fully understand this genus. Furthermore, its bioactive chemicals' structure-activity connection, in vivo activity, and mechanism of action ought to be investigated further.

Anti-obesity, anti-hyperglycaemic, anti-antipyretic and analgesic activities of Globularia alypum extracts

OBJECTIVES

The aim of this study is to evaluate the anti-obesity, anti-hyperglycaemic, analgesic and antipyretic activities of Globularia alypum (GA).

MATERIALS AND METHODS

GA methanol and water extracts (GAME, GAWE) were administered to high-fat-high-glucose diet (HFFD) rats.

RESULTS

This study showed that GAME exhibited the highest antioxidant, anti-α-amylase and anti-lipase activities, with half inhibitory concentration (IC50) values 0.067, 1.05 and 2.97 mg/ml respectively. In HFFD rats, the administration of GAME inhibited lipase activity by 36, 37 and 30% in the intestine, pancreas and serum, respectively, reduced body weight by 17.7% and modulated lipid profile. In addition, administration of GAME to HFFD-rats decreased α-amylase activity, improved glucose level and protected liver function. Furthermore, the administration of GA extracts to rats revealed antipyretic (reduction in writhing by 64%) and analgesic (decrease of temperature by 1.11 °C) activities.

CONCLUSION

This study showed that GA extracts exhibited an anti-obesity, anti-hyperglycaemia, anti-pyretic and analgesic activities.

The R2R3-MYB gene CgMYB4 is involved in the regulation of cell differentiation and fiber development in the stamens of Chelone glabra L

A Plantaginaceae flowering plant, Chelone glabra, is different from Arabidopsis thaliana and cotton (Gossypium hirsutum), as it produces fibers on the anther surface. However, the evolutionary molecular mechanism of how fiber development is controlled in the stamen is unclear. MYB genes are essential transcription factors for trichome and fiber development in plants. In this study, we isolated 29 MYB domain-containing sequences using early-stage anthers and several sets of degenerated primers conserved in the R2R3 domain of the MYB transcription factor. Among them, CgMYB4 is an R2R3-MYB gene encoding 281 amino acids. Phylogenetic analysis showed that CgMYB4 is closely related to GhMYB25L/AmMIXTA, which controls fiber initiation and development in cotton and epidermal cell differentiation in the petals of Antirrhinum. Semiquantitative RT-PCR analysis showed that CgMYB4 is strongly expressed at the stamens and carpels. Overexpression of CgMYB4 significantly enhanced root hair formation in transformed hairy roots, contrary to the root hair numbers, which were reduced in silenced CgMYB4 hairy roots. Moreover, overexpression of CgMYB4 also evidently promoted fiber development at filaments and conical cell-like epidermal cell increases at the anther wall. Our results showed that CgMYB4 is an R2R3-MYB gene and is positively involved in regulating cell division and fiber differentiation in the early stages of stamen development in C. glabra.

Characterization of Polyphenolic Compounds from Bacopa procumbens and Their Effects on Wound-Healing Process

Wounds represent a medical problem that contributes importantly to patient morbidity and to healthcare costs in several pathologies. In Hidalgo, Mexico, the Bacopa procumbens plant has been traditionally used for wound-healing care for several generations; in vitro and in vivo experiments were designed to evaluate the effects of bioactive compounds obtained from a B. procumbens aqueous fraction and to determine the key pathways involved in wound regeneration. Bioactive compounds were characterized by HPLC/QTOF-MS, and proliferation, migration, adhesion, and differentiation studies were conducted on NIH/3T3 fibroblasts. Polyphenolic compounds from Bacopa procumbens (PB) regulated proliferation and cell adhesion; enhanced migration, reducing the artificial scratch area; and modulated cell differentiation. PB compounds were included in a hydrogel for topical administration in a rat excision wound model. Histological, histochemical, and mechanical analyses showed that PB treatment accelerates wound closure in at least 48 h and reduces inflammation, increasing cell proliferation and deposition and organization of collagen at earlier times. These changes resulted in the formation of a scar with better tensile properties. Immunohistochemistry and RT-PCR molecular analyses demonstrated that treatment induces (i) overexpression of transforming growth factor beta (TGF-β) and (ii) the phosphorylation of Smad2/3 and ERK1/2, suggesting the central role of some PB compounds to enhance wound healing, modulating TGF-β activation.

α-Glucosidase Inhibitors from the Stems of Knema globularia

Six new compounds, globunones A-F (1-6), and two new flavonoids (7 and 8) together with nine known compounds (9-17) were isolated from the stems of Knema globularia. The chemical structures of 1-8 were elucidated by an analysis of their NMR and high-resolution electrospray ionization mass spectrometry data as well as by comparison with literature values. The absolute configurations were determined using time-dependent density functional theory electronic circular dichroism (TD-DFT-ECD). Globunones A-E (1-5) represent the initial combined structures of a flavan-3-ol core and a 1,4-benzoquinone core. Globunone F (6) is the first flavanone-type compound bearing a 2-(2,4-dihydroxyphenyl)-2-oxoethyl group found to date in Nature. Compounds 1-3 and 6-17 were tested for their yeast α-glucosidase inhibitory activity. All compounds tested (except for 13 and 14) showed potent inhibition toward α-glucosidase with IC₅₀ values in the range 0.4-26.6 μM. Calodenin A (15) was the most active compound with an IC₅₀ value of 0.4 μM (the positive control, acarbose, IC₅₀ 93.6 μM). A kinetic analysis of 15 revealed that it is a noncompetitive inhibitor with a K_i value of 3.4 μM.

Pioneering polyploids: the impact of whole-genome duplication on biome shifting in New Zealand Coprosma (Rubiaceae) and Veronica (Plantaginaceae)

The role of whole-genome duplication (WGD) in facilitating shifts into novel biomes remains unknown. Focusing on two diverse woody plant groups in New Zealand, Coprosma (Rubiaceae) and Veronica (Plantaginaceae), we investigate how biome occupancy varies with ploidy level, and test the hypothesis that WGD increases the rate of biome shifting. Ploidy levels and biome occupancy (forest, open and alpine) were determined for indigenous species in both clades. The distribution of low-ploidy (Coprosma: 2x, Veronica: 6x) versus high-ploidy (Coprosma: 4-10x, Veronica: 12-18x) species across biomes was tested statistically. Estimation of the phylogenetic history of biome occupancy and WGD was performed using time-calibrated phylogenies and the R package BioGeoBEARS. Trait-dependent dispersal models were implemented to determine support for an increased rate of biome shifting among high-ploidy lineages. We find support for a greater than random portion of high-ploidy species occupying multiple biomes. We also find strong support for high-ploidy lineages showing a three- to eightfold increase in the rate of biome shifts. These results suggest that WGD promotes ecological expansion into new biomes.

Preference Provides a Plethora of Problems (Don't Panic)

This review was solicited as an autobiography. The "problems" in my title have two meanings. First, they were professional difficulties caused by my decision to study oviposition preferences of butterflies that were not susceptible to traditional preference-testing designs. Until I provided video, my claim that the butterflies duplicate natural post-alighting host-assessment behavior when placed on hosts by hand was not credible, and the preference-testing technique that I had developed elicited skepticism, anger, and derision. The second meaning of "problems" is scientific. Insect preference comes with complex dimensionality that interacts with host acceptability. Part Two of this review describes how my group's work in this area has revealed unexpected axes of variation in plant-insect interactions-axes capable of frustrating attempts to derive unequivocal conclusions from apparently sensible experimental designs. The possibility that these complexities are lurking should be kept in mind as preference and performance experiments are devised.

Summer Development and Survivorship of the Weed Biocontrol Agent, Mecinus janthiniformis (Coleoptera: Curculionidae), Within Stems of Its Host, Dalmatian Toadflax (Lamiales: Plantaginaceae), in Utah

The summer phenology and survivorship of the stem-mining weevil, Mecinus janthiniformis Toševski and Caldara, a biocontrol agent of Dalmatian toadflax, Linaria dalmatica (L.) Miller, was studied in 2015-2016 as it developed within host plant stems at a low elevation, open rangeland site in northern Utah. Hatching from eggs in spring and early summer, weevils occurred as larvae within stems in June. Earliest maturing adults occurred in mid-July, and the majority of individuals had completed pupal development by early August. Survivorship within stems was high, with two-thirds or more of individuals surviving from egg hatch to adulthood as assessed in mid-September. Mortality rates within stems were highest during larval development, with parasitism accounting for the majority of deaths. At least three parasitoid species (Chalcidoidea: Pteromalidae and Eupelmidae), including both endoparasitoids and ectoparasitoids, were found attacking weevils within stems. Although most surviving weevils remained as adults within stems to overwinter, some adults were found to have chewed exit holes, and in some cases had exited from stems, beginning in July; the fate of these prematurely exiting adults is unknown. Low summer mortality rates within stems should promote weevil establishment under the hot, dry conditions of northern Utah, but parasitism and premature exiting of adults from host stems merit further investigation concerning their potential to reduce biocontrol efficacy. The results presented here for M. janthiniformis phenology within host stems will contribute to the development of standardized, summer monitoring for this biocontrol agent by stem dissection.

Selection of native plants with phytoremediation potential for highly contaminated Mediterranean soil restoration: Tools for a non-destructive and integrative approach

The aim of this study was to develop an effective and non-destructive method for the selection of native Mediterranean plants with phytoremediation potential based on their spontaneous recovery capacities. The study site consisted in a mixed contaminated soils (As, Cu, Pb, Sb, Zn) in the vicinity of a former lead smelting factory abandoned since 1925 in the Calanques National Park (Marseille, southeastern France). We developed an integrated characterization approach that takes into account topsoil metal(loid)s (MM) contamination, plant community composition and structure and mesologic parameters without using destructive methods. From a statistical selection of significant environmental descriptors, plant communities were described and interpreted as the result of spontaneous recovery under multiple stresses and local conditions (both natural and anthropogenic). We collected phytoecological and MM topsoil data using field monitoring and geographic information system (GIS) on a pollution hotspot where natural plant communities occur. The results of the multivariate analysis performed between species and descriptors indicated that a century of MM pollution pressure produced a significant correlation with plant community dynamics in terms of composition, diversity and structure, leading to the co-occurrence of different plant succession stages. Thus, these successions seemed linked to the variability of anthropogenic disturbance regimes within the study site. We recorded high topsoil contamination heterogeneity at the scale both of the plot and of the whole study area that suggested a heterogeneous MM distribution pattern dependent on the source of contaminants and site environmental variability. We identified 4 spontaneous plant communities co-occurring through a MM contamination gradient that could be used later from degraded to reference communities to define ecological restoration target combined to phytoremediation applications with respect to local conditions. Our results suggested that some of the native plant species such as Coronilla juncea and Globularia alypum might be tolerant to high mixed MM soil concentrations and they could thus be used for phytostabilization purposes in polluted Mediterranean areas in regard to their life-traits. Our non-destructive methodology led both to the selection of tolerant native plant species and communities and identification of highly polluted priority intervention areas through the study site where phytostabilization should be implemented. Furthermore, by analyzing succession dynamics linked to contamination patterns throughout the area and spontaneous recovery of native tolerant vegetation, our methodology opens up broad perspectives and research fields for ecological restoration for Mediterranean protected and contaminated areas based on ecosystem trajectories and new approaches for the integrative management of polluted soils.

Antipyretic, analgesic and anti-inflammatory effects of Kickxia ramosissima

ETHNOPHARMACOLOGICAL RELEVANCE

Branched cancerwort, Kickxia ramosissima (Wall.) Janchen (Scrophulariaceae) is traditionally used for the treatment of inflammatory disorders such as rheumatism, diabetes, jaundice and for activation of immune system. Local communities also used this plant for the treatment of spleen enlargement, as febrifuge and in dysmenorrhea. In this investigation antipyretic, analgesic and anti-inflammatory effects of K. ramosissima have been evaluated.

METHODS

Dried powder of the whole plant of K. ramosissima was extracted with methanol (KRM) and partitioned with solvents to obtain the n-hexane (KRH), chloroform (KRC), ethyl acetate (KRE), n-butanol (KRB) and the residual aqueous (KRA) fraction. KRM and the derived fractions were analyzed for the phytochemical constituents, yeast induced pyrexia, analgesic and anti-inflammatory activities by using carrageenan and Freunds' complete adjuvant-induced paw edema model in rat. On account of appreciable effects of KRM in the aforesaid models, KRM was subjected to the carrageenan induced air pouch model in rat. The exudate of air pouch was analyzed for the count of neutrophils, monocytes, lymphocytes and WBCs and for the estimation of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), nitric oxide (NO) and prostaglandin (PGE2).

RESULTS

Phytochemical investigation of KRM indicated the existence of tannins, flavonoids, alkaloids, coumarins, cardiac glycosides, saponins, terpenoids and phlobatannins. Maximum concentration of total phenolic was determined in KRB followed by KRM while reverse was true for total flavonoids contents. KRM (200mg/kg) distinctly decreased the rectal temperature in yeast induced pyrexia comparable to standard, paracetamol. Pain sensation was effectively inhibited at 200mg/kg p.o. of KRM and KRB as manifested by a decrease (P<0.001) in count of writhing induced with acetic acid and increase of latency time in hot plate. Anti-inflammatory effects of KRM were evident and edema formation induced with carrageenan and Freunds' complete adjuvant-induced paw edema in rat was significantly (P<0.001) inhibited. Count of neutrophils, monocytes, lymphocytes, and WBCs along with inflammatory mediators; IL-6, NO, TNF-α and PGE2 was significantly (P<0.001) decreased in subcutaneous air pouch exudate with KRM. HPLC analysis of KRM indicated the presence of gallic acid, caffeic acid, rutin, catechin and myricetin.

CONCLUSION

The results suggested the anti-inflammatory effects of KRM in inflammation related disorders, might be attributed by the presence of active phytoconstituents; flavonoids, saponins and terpenoids.

Bioactivites of two common polyphenolic compounds: Verbascoside and catechin

CONTEXT

Natural products can present remarkable biological and pharmacological activities. In traditional medicine, plants have been used historically in treating cancer, infections, and other inflammatory conditions.

OBJECTIVE

Verbascoside and catechin are widespread polyphenolic plant compounds that could play a role in the anti-inflammatory and health-promoting effects of plants and plant extracts.

MATERIALS AND METHODS

This study compares the potential cytotoxic effects of polyphenols verbascoside and catechin (6.25-200 µM) on human peripheral blood mononuclear cells (PBMC) for 48 h and myelomonocytic THP-1 and THP-1 Blue cells for 24 h. The effects of the compounds on immune activation markers such as indoleamine 2,3-dioxygenase (IDO) activity as well as on neopterin formation and nuclear factor-κB (NF-κB) activation were investigated. Cytotoxicity of the compounds was tested using Cell-Titer Blue assay.

RESULTS

Verbascoside exhibited significant suppressive effects in mitogen-stimulated PBMC on tryptophan breakdown (>50 µM; IC50 value: 58.6 µM) and the production of neopterin (>6.25 µM; IC50 value: 217 µM). These effects correlated with a decline in cell viability, while THP-1 Blue cells were less sensitive. NF-κB activity was slightly enhanced at lower concentrations (<50 µM verbascoside) in stimulated cells and at the highest concentration used in unstimulated cells. Catechin had no relevant effects on cell viability and on the tested inflammation markers, except NF-κB activation in THP-1 Blue cells.

DISCUSSION AND CONCLUSION

The results obtained show that verbascoside and catechin represent effective compounds which interfere with immunobiochemical pathways that are highly relevant for immunosurveillance and competing virus infections.

coli K12 growth in vitro: Possible relation to phytochemical properties

CONTEXT

The data concerning the influence of Plantaginaceae water extracts on bacterial growth are contradictory.

OBJECTIVE

This study investigates the influence of Plantago maxima Juss. ex Jacq., Plantago lanceolata L., Plantago major L., Veronica teucrium L., Veronica spicata L., and Veronica incana L. aqueous extracts on growth of Escherichia coli K12 culture and the relation to antioxidant, reducing, and iron-binding activities.

MATERIALS AND METHODS

Aqueous extracts were prepared from the dried leaves with the final concentration of 1/10, 1/15, 1/20, 1/25, 1/30, 1/35, and 1/40 (w/w). Comparative analysis of total flavonoids, iridoids, and tannins in Plantaginaceae species was performed. Iron-binding, antioxidant, and reducing activities of plant extracts were analyzed spectrophotometrically. The influence of plant extracts on E. coli K12 growth was studied in vitro by estimating the bacterial growth in the extract-containing medium.

RESULTS

Total tannin content in plant leaves positively correlated with iron-binding activity (r = 0.641), whereas total flavonoids correlated with antioxidant activity (r = 0.687). In an in vitro model, it is estimated that water extracts of studied Plantaginaceae species stimulated bacterial growth. Prebiotic activity significantly of 1/20 and 1/40 plant extracts positively correlated with antioxidant (r = 0.589; r = 0.576, respectively) and reducing activity (r = 0.721; r = 0.620, respectively) of plant aqueous extracts at 6-24 h. Negative correlation was observed between iron-binding activity and bacterial growth (r = -0.503 and r = -0.534 for 1/20 and 1/40 extracts, respectively).

CONCLUSION

Aqueous Plantaginaceae extracts possess prebiotic activity depending on the phytochemical content of plant leaves.