Phytochemical Comparison of the Water and Ethanol Leaf Extracts of the Cree medicinal plant, Sarracenia purpurea L. (Sarraceniaceae)

New Green Approaches in Nanoparticles Synthesis: An Overview

Nanotechnology is constantly expanding, with nanomaterials being more and more used in common commercial products that define our modern life. Among all types of nanomaterials, nanoparticles (NPs) occupy an important place, considering the great amount that is produced nowadays and the diversity of their applications. Conventional techniques applied to synthesize NPs have some issues that impede them from being appreciated as safe for the environment and health. The alternative to these might be the use of living organisms or biological extracts that can be involved in the green approach synthesis of NPs, a process that is free of harmful chemicals, cost-effective and a low energy consumer. Several factors, including biological reducing agent concentration, initial precursor salt concentration, agitation, reaction time, pH, temperature and light, can influence the characteristics of biologically synthesized NPs. The interdependence between these reaction parameters was not explored, being the main impediment in the implementation of the biological method on an industrial scale. Our aim is to present a brief review that focuses on the current knowledge regarding how the aforementioned factors can control the size and shape of green-synthesized NPs. We also provide an overview of the biomolecules that were found to be suitable for NP synthesis. This work is meant to be a support for researchers who intend to develop new green approaches for the synthesis of NPs.

Secondary Metabolites with Biomedical Applications from Plants of the Sarraceniaceae Family

Carnivorous plants have fascinated researchers and hobbyists for centuries because of their mode of nutrition which is unlike that of other plants. They are able to produce bioactive compounds used to attract, capture and digest prey but also as a defense mechanism against microorganisms and free radicals. The main purpose of this review is to provide an overview of the secondary metabolites with significant biological activity found in the Sarraceniaceae family. The review also underlines the necessity of future studies for the biochemical characterization of the less investigated species. Darlingtonia, Heliamphora and Sarracenia plants are rich in compounds with potential pharmaceutical and medical uses. These belong to several classes such as flavonoids, with flavonol glycosides being the most abundant, monoterpenes, triterpenes, sesquiterpenes, fatty acids, alkaloids and others. Some of them are well characterized in terms of chemical properties and biological activity and have widespread commercial applications. The review also discusses biological activity of whole extracts and commercially available products derived from Sarraceniaceae plants. In conclusion, this review underscores that Sarraceniaceae species contain numerous substances with the potential to advance health. Future perspectives should focus on the discovery of new molecules and increasing the production of known compounds using biotechnological methods.

Bioactive Pentacyclic Triterpenes from the Root Bark Extract of Myrianthus arboreus, a Species Used Traditionally to Treat Type-2 Diabetes

Four new Δ¹² ursene-type pentacyclic triterpenes containing the trans-feruloyl moiety (1-4), along with ursolic acid (5), were isolated from a Myrianthus arboreus root bark ethanol extract, after bioassay-guided subfractionation of its hexane fraction. The structures of 1-4 were established on the basis of the results of standard spectroscopic analytical methods (IR, HRESIMS, GC-MS, 1D and 2D NMR). The compounds 3β- O- trans-feruloyl-2α,19α-dihydroxyurs-12-en-28-oic acid (1), 2α-acetoxy-3β- O- trans-feruloyl-19α-hydroxyurs-12-en-28-oic acid (3), and 5 were determined to decrease the activity of hepatocellular glucose-6-phosphatase (G6Pase) and to activate glycogen synthase (GS). Their action on G6Pase activity implicated both Akt and AMPK activation. In addition, these compounds were determined to stimulate GS via the phosphorylation of glycogen synthase kinase-3. Compound 3 showed the most potent effect in modulating glucose homeostasis in liver cells. This is the first comprehensive report on novel phytochemical components of the root bark extract of M. arboreus based on the isolation of the principles responsible for its antidiabetic effects.

Root bark extracts of Myrianthus arboreus P. Beauv. (Cecropiaceae) exhibit anti-diabetic potential by modulating hepatocyte glucose homeostasis

ETHNOPHARMACOLOGICAL RELEVANCE

Myrianthus arboreus P. Beauv. is a tropical tree used in African folk medicine, including for diabetes. However, little research has yet been conducted to support this ethnopharmacological use of this plant. The present study sought to determine the antidiabetic potential of root bark extracts through cell-based bioassays of liver and muscle glucose homeostasis.

MATERIALS AND METHODS

Four extracts were obtained from crude root bark powder: 1 aqueous (AQ), 2 ethanol (EtOH), 3 alkaloid enriched (Alk) (obtained from methanol extract) and 4 dichloromethane (Dic) extracts. Moreover, extract 2 was further separated into two fractions: 2.1 ethyl acetate (EAc) and 2.2 hexane (Hex). To assess the antidiabetic activity of the plant extracts, inhibition of glucose-6-phosphatase (G6Pase), stimulation of glycogen synthase (GS) and modulation of glucose uptake were determined in cultured H4IIE and HepG2 hepatocytes as well as C2C12 myocytes, respectively. Phosphorylation of three kinases, AMP-activated protein kinase (AMPK), Akt and Glycogen Synthase Kinase-3 (GSK-3) were probed by Western blot.

RESULTS

M. arboreus extracts/fractions did not stimulate glucose uptake in C2C12 cells albeit 2.2 (Hex) fraction showed a mild positive tendency. In contrast, extract 2 and its fractions as well as extract 3 were able to decrease hepatocyte G6Pase activity. Their effect on G6Pase activity involved both Akt and AMPK phosphorylation. No significant correlation was observed between activation of Akt and inhibition of G6Pase (R² = 0.50 p < 0.14), whereas that between stimulation of AMPK and inhibition of G6Pase was statistically significant (R² = 0.75 p < 0.05). On the other hand, extract 2, its fraction 2.2 and extract 3 were able to stimulate GS through GSK-3 phosphorylation. A high correlation was observed between the ability of M. arboreus extracts and fractions to phosphorylate GSK-3 and modulate GS activity (R²=0.81 p < 0.01). Extract 2 and its fraction 2.2 together with extract 3 were the only plant products to simultaneously and potently regulate G6Pase and GS, the key players of hepatic glucose homeostasis.

CONCLUSION

Overall, these data support the traditional antidiabetic uses of the root bark of M. arboreus.

Metabolite profiling of the carnivorous pitcher plants Darlingtonia and Sarracenia

Sarraceniaceae is a New World carnivorous plant family comprising three genera: Darlingtonia, Heliamphora, and Sarracenia. The plants occur in nutrient-poor environments and have developed insectivorous capability in order to supplement their nutrient uptake. Sarracenia flava contains the alkaloid coniine, otherwise only found in Conium maculatum, in which its biosynthesis has been studied, and several Aloe species. Its ecological role and biosynthetic origin in S. flava is speculative. The aim of the current research was to investigate the occurrence of coniine in Sarracenia and Darlingtonia and to identify common constituents of both genera, unique compounds for individual variants and floral scent chemicals. In this comprehensive metabolic profiling study, we looked for compound patterns that are associated with the taxonomy of Sarracenia species. In total, 57 different Sarracenia and D. californica accessions were used for metabolite content screening by gas chromatography-mass spectrometry. The resulting high-dimensional data were studied using a data mining approach. The two genera are characterized by a large number of metabolites and huge chemical diversity between different species. By applying feature selection for clustering and by integrating new biochemical data with existing phylogenetic data, we were able to demonstrate that the chemical composition of the species can be explained by their known classification. Although transcriptome analysis did not reveal a candidate gene for coniine biosynthesis, the use of a sensitive selected ion monitoring method enabled the detection of coniine in eight Sarracenia species, showing that it is more widespread in this genus than previously believed.

The Role of Monocarboxylate Transporters and Their Chaperone CD147 in Lactate Efflux Inhibition and the Anticancer Effects of Terminalia chebula in Neuroblastoma Cell Line N2-A

AIMS

In the presence of oxygen, most of the synthesized pyruvate during glycolysis in the cancer cell of solid tumors is released away from the mitochondria to form lactate (Warburg Effect). To maintain cell homeostasis, lactate is transported across the cell membrane by monocarboxylate transporters (MCTs). The major aim of the current investigation is to identify novel compounds that inhibit lactate efflux that may lead to identifying effective targets for cancer treatment.

STUDY DESIGN

In this study, 900 ethanol plant extracts were screened for their lactate efflux inhibition using neuroblastoma (N2-A) cell line. Additionally, we investigated the mechanism of inhibition for the most potent plant extract regarding monocarboxylate transporters expression, and consequences effects on viability, growth, and apoptosis.

METHODOLOGY

The potency of lactate efflux inhibition of ethanol plant extracts was evaluated in N2-A cells by measuring extracellular lactate levels. Caspase 3- activity and acridine orange/ethidium bromide staining were performed to assess the apoptotic effect. The antiproliferative effect was measured using WST assay. Western blotting was performed to quantify protein expression of MCTs and their chaperone CD147 in treated cells lysates.

RESULTS

Terminalia chebula plant extract was the most potent lactate efflux inhibitor in N2-A cells among the 900 - tested plant extracts. The results obtained show that extract of Terminalia chebula fruits (TCE) significantly (P = 0.05) reduced the expression of the MCT1, MCT3, MCT4 and the chaperone CD147. The plant extract was more potent (IC₅₀ of 3.59 ± 0.26 μg/ml) than the MCT standard inhibitor phloretin (IC₅₀ 76.54 ± 3.19 μg/ml). The extract also showed more potency and selective cytotoxicity in cancer cells than DI-TNC1 primary cell line (IC₅₀ 7.37 ± 0.28 vs. 17.35 ± 0.19 μg/ml). Moreover, TCE Inhibited N2-A cell growth (IG₅₀ = 5.20 ± 0.30 μg/ml) and induced apoptosis at the 7.5 μg/ml concentration.

CONCLUSION

Out of the 900 plant extracts screened, Terminalia chebula ethanol extract was found to be the most potent lactate efflux inhibitor with the ability to inhibit chaperone CD147 expression and impact the function of monocarboxylate transporters. Furthermore, TCE was found to have growth inhibition and apoptotic effects. The results obtained indicate that Terminalia chebula constituent(s) may contain promising compounds that can be useful in the management of neuroblastoma cancer.