Chemical Profile of Lipophilic Fractions of Different Parts of Zizyphus lotus L. by GC-MS and Evaluation of Their Antiproliferative and Antibacterial Activities.

Zizyphus lotus L. is a perennial shrub particularly used in Algerian folk medicine, but little is known concerning the lipophilic compounds in the most frequently used parts, namely, root bark, pulp, leaves and seeds, which are associated with health benefits. In this vein, the lipophilic fractions of these morphological parts of Z. lotus from Morocco were studied by gas chromatography-mass spectrometry (GC-MS), and their antiproliferative and antimicrobial activities were evaluated. GC-MS analysis allowed the identification and quantification of 99 lipophilic compounds, including fatty acids, long-chain aliphatic alcohols, pentacyclic triterpenic compounds, sterols, monoglycerides, aromatic compounds and other minor components. Lipophilic extracts of pulp, leaves and seeds were revealed to be mainly composed of fatty acids, representing 54.3-88.6% of the total compounds detected. The leaves and seeds were particularly rich in unsaturated fatty acids, namely, (9Z,12Z)-octadeca-9,12-dienoic acid (2431 mg kg-1 of dry weight) and (9Z)-octadec-9-enoic acid (6255 mg kg-1 of dry weight). In contrast, root bark contained a high content of pentacyclic triterpenic compounds, particularly betulinic acid, accounting for 9838 mg kg-1 of dry weight. Root bark extract showed promising antiproliferative activity against a triple-negative breast cancer cell line, MDA-MB-231, with a half-maximal inhibitory concentration (IC50) = 4.23 ± 0.18 µg mL-1 of extract. Leaf extract displayed interesting antimicrobial activity against Escherichia coli, methicillin-sensitive Staphylococcus aureus and Staphylococcus epidermis, presenting minimum inhibitory concentration (MIC) values from 1024 to 2048 µg mL-1 of extract. Our results demonstrate that Zizyphus lotus L. is a source of promising bioactive components, which can be exploited as natural ingredients in pharmaceutical formulations.

Metabolic Effects of a Eucalyptus Bark Lipophilic Extract on Triple Negative Breast Cancer and Nontumor Breast Epithelial Cells.

In this work, untargeted metabolomics was used to unveil the impact of a Eucalyptus (Eucalyptus nitens) outer bark lipophilic extract on the metabolism of triple negative breast cancer (TNBC) and nontumor breast cells. Integrative analysis of culture medium, intracellular polar metabolites, and cellular lipids provided a comprehensive picture of cell metabolic adaptations, which enabled several hypotheses about the metabolic targets and pathways affected to be proposed. One of the most marked effects in MDA-MB-231 breast cancer cells, upon 48 h incubation with the E. nitens extract (15 µg/mL), was the enhancement of the NAD+/NADH ratio, likely reflecting a shift to mitochondrial respiration, which appeared to be fueled by amino acids and fatty acids resulting from hydrolysis of neutral lipids (triglycerides and cholesteryl esters). Contrastingly, in MCF-10A breast epithelial cells, the E. nitens extract appeared to intensify glycolysis and the tricarboxylic acid cycle (resulting in a decreased NAD+/NADH ratio), while having no effect on the cell lipid composition. This knowledge improves the current understanding of the biological activity of E. nitens bark extracts and is potentially useful to promote their development in the field of TNBC anticancer therapy.

Development of bioactive films based on chitosan and Cynara cardunculus leaves extracts for wound dressings.

The development of natural based, effective and protective wound dressings associated to local treatment applied on chronic wounds, represents a major challenge nowadays. In this work chitosan-based films were prepared with different concentrations of ethanolic ultrasound assisted extracts from Cynara cardunculus leaves (EtPUAE). The physico-chemical film properties revealed that extract incorporation influences the volumetric swelling capacity and mechanical properties of the films, leading to materials with a lower fluid absorption capacity and more fragile. However, no impact was detected on the thermal properties of the films, as well as on their dense structure characterized by Scanning Electronic Microscopy (SEM) analysis. Biological screening of chitosan-based films show that chitosan with a 1% (w/w) and a 5% (w/w) EtPUAE loading did not induce cytotoxicity on normal human skin fibroblasts (Bj5-ta cell line), mainly attributed to cynaropicrin (extract key active compound) present in the film below its IC50 value. Nevertheless, chitosan-based films with 5% (w/w) EtPUAE presented an interesting anti-inflammatory activity. Bj5-ta cells stimulated with liposaccharides (LPS), presented a reduction of 86% on IL-6 cytokine levels, after exposure to chitosan with 5% EtPUAE film extract. The results obtained in this study open up the possibility of successfully using chitosan films doped with EtPUAE for development of chronic wound dressings, with the advantage of using naturally-sourced materials with anti-inflammatory activity.

Antimicrobial activity of pomegranate peel extracts performed by high pressure and enzymatic assisted extraction.

This study aimed to assess the effect of high pressure (300 and 600 MPa) and enzymatic extraction (pectinase and cellulase) on the phenolic compounds profile, antioxidant capacity and antimicrobial activity of extracts from pomegranate by-products. Antimicrobial activity against eight different strains of pathogenic and contaminant bacteria and against five beneficial bacteria including Lactobacillus and Bifidobacterium strains were determined. The maximum level of total phenolic content, as well as antioxidant capacity were observed at 300 MPa, however enzymatic extraction did not improve the extraction yields. Punicalagin isomers and bis-hexahydroxydiphenoyl-glucoside isomer were the most abundant phenolic compounds found in the extracts. All pomegranate peel extracts demonstrated selective antimicrobial activity against all pathogenic bacteria without affecting beneficial ones. Pressurized extracts presented lower minimum inhibitory concentration against Bacillus cereus and Pseudomonas aeruginosa and lower minimum bactericidal concentration against B. cereus, while, enzymatic extracts presented lower minimum bactericidal concentration for Staphylococcus aureus, Methicillin-resistant Staphylococcus aureus and Listeria monocytogenes. Principal component analyses reveled that antioxidant activity and phenolic compounds content were strongly related with antimicrobial activity. Pomegranate peels extracts obtained by high pressure extraction could so be used as a source of high added-value bioactive compounds for antioxidant and antimicrobial applications.

Targeting Tumor Metabolism with Plant-Derived Natural Products: Emerging Trends in Cancer Therapy.

Recognition of neoplastic metabolic reprogramming as one of cancer's hallmarks has paved the way for developing novel metabolism-targeted therapeutic approaches. The use of plant-derived natural bioactive compounds for this endeavor is especially promising, due to their diverse structures and multiple targets. Hence, over the past decade, a growing number of studies have assessed the impact of phytochemicals on tumor cell metabolism, aiming at improving current knowledge on their mechanisms of action and, at the same time, evaluating their potential as anti-cancer metabolic modulators. In this Review, we focus on three classes of plant-derived compounds with promising anti-cancer activity-phenolic compounds, isoprenoids, and alkaloids-to describe their effects on major energetic and biosynthetic pathways of human tumor cells. Such a comprehensive and integrated account of the ability of these compounds to hit different metabolic targets is expected to contribute to the rational design and critical assessment of novel anti-cancer therapies based on natural-product-mediated metabolic reprogramming.

Haplotype analysis of the germacrene A synthase gene and association with cynaropicrin content and biological activities in Cynara cardunculus.

Cynara cardunculus: L. represents a natural source of terpenic compounds, with the predominant molecule being cynaropicrin. Cynaropicrin is gaining interest since it has been correlated to anti-hyperlipidaemia, antispasmodic and cytotoxicity activity against leukocyte cancer cells. The objective of this work was to screen a collection of C. cardunculus, from different origins, for new allelic variants in germacrene A synthase (GAS) gene involved in the cynaropicrin biosynthesis and correlate them with improved cynaropicrin content and biological activities. Using high-resolution melting, nine haplotypes were identified. The putative impact of the identified allelic variants in GAS protein was evaluated by bioinformatic tools and polymorphisms that putatively lead to protein conformational changes were described. Additionally, cynaropicrin and main pentacyclic triterpenes contents, and antithrombin, antimicrobial and antiproliferative activities were also determined in C. cardunculus leaf lipophilic-derived extracts. In this work we identified allelic variants with putative impact on GAS protein, which are significantly associated with cynaropicrin content and antiproliferative activity. The results obtained suggest that the identified polymorphisms should be explored as putative genetic markers correlated with biological properties in Cynara cardunculus.

Lipophilic Fraction of Cultivated Bifurcaria bifurcata R. Ross: Detailed Composition and In Vitro Prospection of Current Challenging Bioactive Properties.

Macroalgae have been seen as an alternative source of molecules with promising bioactivities to use in the prevention and treatment of current lifestyle diseases. In this vein, the lipophilic fraction of short-term (three weeks) cultivated Bifurcaria bifurcata was characterized in detail by gas chromatography-mass spectrometry (GC-MS). B. bifurcata dichloromethane extract was composed mainly by diterpenes (1892.78 ± 133.97 mg kg-1 dry weight (DW)), followed by fatty acids, both saturated (550.35 ± 15.67 mg kg-1 DW) and unsaturated (397.06 ± 18.44 mg kg-1 DW). Considerable amounts of sterols, namely fucosterol (317.68 ± 26.11 mg kg-1 DW) were also found. In vitro tests demonstrated that the B. bifurcata lipophilic extract show antioxidant, anti-inflammatory and antibacterial activities (against both Gram-positive and Gram-negative bacteria), using low extract concentrations (in the order of µg mL-1). Enhancement of antibiotic activity of drug families of major clinical importance was observed by the use of B. bifurcata extract. This enhancement of antibiotic activity depends on the microbial strain and on the antibiotic. This work represents the first detailed phytochemical study of the lipophilic extract of B. bifurcata and is, therefore, an important contribution for the valorization of B. bifurcata macroalgae, with promising applications in functional foods, nutraceutical, cosmetic and biomedical fields.

Antiproliferative Effects of Cynara cardunculus L. var. altilis (DC) Lipophilic Extracts.

Besides being traditionally used to relieve hepatobiliary disorders, Cynara cardunculus L. has evidenced anticancer potential on triple-negative breast cancer (TNBC). This study highlights the antiproliferative effects of lipophilic extracts from C. cardunculus L. var. altilis (DC) leaves and florets, and of their major compounds, namely cynaropicrin and taraxasteryl acetate, against MDA-MB-231 cells. Our results demonstrated that MDA-MB-231 cells were much less resistant to leaves extract (IC50 10.39 µg/mL) than to florets extract (IC50 315.22 µg/mL), during 48 h. Moreover, leaves extract and cynaropicrin (IC50 6.19 µg/mL) suppressed MDA-MB-231 cells colonies formation, via an anchorage-independent growth assay. Leaves extract and cynaropicrin were also assessed regarding their regulation on caspase-3 activity, by using a spectrophotometric assay, and expression levels of G2/mitosis checkpoint and Akt signaling pathway proteins, by Western blotting. Leaves extract increased caspase-3 activity, while cynaropicrin did not affect it. Additionally, they caused p21Waf1/Cip1 upregulation, as well as cyclin B1 and phospho(Tyr15)-CDK1 accumulation, which may be related to G2 cell cycle arrest. They also downregulated phospho(Ser473)-Akt, without changing total Akt1 level. Cynaropicrin probably contributed to leaves extract antiproliferative action. These promising insights suggest that cultivated cardoon leaves lipophilic extract and cynaropicrin may be considered toward a natural-based therapeutic approach on TNBC.

Oleanolic, Ursolic, and Betulinic Acids as Food Supplements or Pharmaceutical Agents for Type 2 Diabetes: Promise or Illusion?

Oleanolic (OA), ursolic (UA), and betulinic (BA) acids are three triterpenic acids (TAs) with potential effects for treatment of type 2 diabetes (T2DM). Mechanistic studies showed that these TAs act as hypoglycemic and antiobesity agents mainly through (i) reducing the absorption of glucose; (ii) decreasing endogenous glucose production; (iii) increasing insulin sensitivity; (iv) improving lipid homeostasis; and (v) promoting body weight regulation. Besides these promising beneficial effects, it is believed that OA, UA, and BA protect against diabetes-related comorbidities due to their antiatherogenic, anti-inflammatory, and antioxidant properties. We also highlight the protective effect of OA, UA, and BA against oxidative damage, which may be very relevant for the treatment and/or prevention of T2DM. In the present review, we provide an integrative description of the antidiabetic properties of OA, UA, and BA, evaluating the potential use of these TAs as food supplements or pharmaceutical agents to prevent and/or treat T2DM.

Role of Isoprenoid Compounds on Angiogenic Regulation: Opportunities and Challenges.

Isoprenoids represent one of the largest classes of phytochemicals. The structural diversity of these compounds, as well as their remarkable biological activities, makes them suitable candidates for the development of novel therapeutic agents. Several isoprenoids have demonstrated promising potential in the modulation of angiogenesis processes, and therefore provide an appealing alternative and/or addition to the available pharmacotherapies. These compounds could be used per se or combined with standard therapies, which can potentially reduce the undesired secondary effects. Compounds like the sesquiterpenoid artemisinin, and its derivatives, or the diterpenoid triptolide have been successfully tested in a broad range of models (in vitro and in vivo). Moreover, sesquiterpenoids seem to be a promising resource of natural angiogenic modulators, as it can be attested by the significant number of recent publications in this subject. On the other hand, other isoprenoids, such as the triterpenoid ursolic acid, are still under-explored and further studies are needed to understand their role within angiogenic process. Further insights into isoprenoids mode of action in angiogenesis will hopefully pave the way towards their successful clinical use.

Lipophilic extracts of Cynara cardunculus L. var. altilis (DC): a source of valuable bioactive terpenic compounds.

Lipophilic extracts of Cynara cardunculus L. var. altilis (DC) from the south of Portugal (Baixo Alentejo) were studied by gas chromatography-mass spectrometry. One sesquiterpene lactone, four pentacyclic triterpenes, and four sterols were reported for the first time as cultivated cardoon components, namely, deacylcynaropicrin, ß- and α-amyrin, lupenyl and ψ-taraxasteryl acetates, stigmasterol, 24-methylenecholesterol, campesterol, and Δ(5)-avenasterol. In addition, other new compounds were identified: ten fatty acids, eight long-chain aliphatic alcohols, and six aromatic compounds. Four triterpenyl fatty acid esters were also detected. Sesquiterpene lactones and pentacyclic triterpenes were the major lipophilic families, representing respectively 2-46% and 10-89% of the detected compounds. Cynaropicrin was the most abundant sesquiterpene lactone, while taraxasteryl acetate was the main pentacyclic triterpene. Fatty acids and sterols, mainly hexadecanoic acid and ß-sitosterol, were present at lower amounts (1-20% and 1-11% of the detected compounds). Long-chain aliphatic alcohols and aromatic compounds were detected at reduced abundances (1-6% of the detected compounds).