Inhibition of the CYP Enzymatic System Responsible of Heterocyclic Amines Bioactivation by an Asclepias subulata Extract.

Asclepias subulata plant extract has previously demonstrated antiproliferative activity and antimutagenicity against heterocyclic aromatic amines (HAAs) commonly found in cooked meat. The objective of this work was to evaluate the in vitro ability of an ethanolic extract from the medicinal plant Asclepias subulata extract (ASE), non-heated and heated (180 °C), to inhibit the activity of CYP1A1 and CYP1A2, which are largely responsible for HAAs bioactivation. Ethoxyresorufin and methoxyresorufin O-dealkylation assays were performed in rat liver microsomes exposed to ASE (0.002-960 µg/mL). ASE exerted an inhibitory effect in a dose-dependent manner. The half inhibitory concentration (IC50) for unheated ASE was 353.6 µg/mL and 75.9 µg/mL for heated ASE in EROD assay. An IC40 value of 288.4 ± 5.8 µg/mL was calculated for non-heated ASE in MROD assay. However, after heat treatment, the IC50 value was 232.1 ± 7.4 µg/mL. Molecular docking of corotoxigenin-3-O-glucopyranoside, one of the main components of ASE, with CYP1A1/2 structure, was performed. Results show that the interaction of corotoxigenin-3-O-glucopyranoside with CYP1A1/2s' α-helices, which are related with the active site and the heme cofactor, may explain the plant extract's inhibitory properties. Results showed that ASE inhibits CYP1A enzymatic subfamily and may potentially act as a chemopreventive agent by inhibiting bioactivation of promutagenic dietary HAAs.

Microencapsulation of Phenolic Extract from Sea Grape (Coccoloba uvifera L.) with Antimutagenic Activity.

This study aimed to microencapsulate the sea grape ethanolic extract by the spray drying process, characterizing the obtained powder, and evaluating its antimutagenicity activity. Microparticles showed a mean size of 6.28 µm and a spherical shape with a smooth surface. The powder had a low moisture content (4.02±0.92 %) and water activity (0.27±0.01), and high solubility (76±3.60 %). Moreover, hygroscopicity (14.75±2.63 g/100 g of powder) and bulk density (0.63±0.03 g/cm3 ) values suggested that this powder can be easily handled at a pilot or industrial scale. In addition, microencapsulation protected the extract against oxidation by ultraviolet light, improved its thermal stability, and its antimutagenicity activity was similar to fresh sea grape extract. In conclusion, the microencapsulation with maltodextrin by spray drying technique is an alternative to protect bioactive compounds from sea grapes against environmental conditions, maintaining their antimutagenic activity.

Antimutagenic, Antiproliferative and Antioxidant Properties of Sea Grape Leaf Extract Fractions (Coccoloba uvifera L.).

BACKGROUND: Cancer is a disease characterized by the invasion and uncontrolled growth of cells. One of the best ways to minimize the harmful effects of mutagens is through the use of natural antimutagens. In this regard, the search for new antimutagens that act in the chemoprevention could represent a promising field in this area. OBJECTIVE: In this study biological potential of 11 fractions from Coccoloba uvifera L. leaf hexane extract was evaluated by several in vitro tests. METHODS: Leaves were lyophilized and hexane extraction was performed. The extract was fractionated by column chromatography with hexane, ethyl acetate, and methanol. The antimutagenic (Ames test), antiproliferative (MTT test), and antioxidant capacity (DPPH, ABTS, and ferrous ion chelation) of the fractions were evaluated. RESULTS: Fractions 4, 6, 8, and 9 have antimutagenic activity (against sodium azide in strain TA100), fraction 11 showed antiproliferative capacity (IC50 of 24 ± 9 µg/mL in cells of HCT 116). The fractions with the highest activity were analyzed by HPLC-MS and lupeol, acacetin, and ß-sitosterol were identified. CONCLUSION: This study demonstrates, for the first time, the bioactivity of C. uvifera leaf as a new source of High Biological Value Compounds (HBVC), which can be of interest to the food and pharmaceutical industries.

Antimutagenic effect of an Asclepias subulata extract against heterocyclic aromatic amines commonly found in cooked meat and its heat stability.

The antimutagenicity of an extract from the medicinal plant Asclepias subulata (ASE) against heterocyclic aromatic amines (HAAs) commonly found in cooked meat, as well as its stability to heat treatment (HT), was evaluated. HT (180 °C/3 min) had no effect on the content in ASE of the bioactive compound corotoxigenin-3-O-glucopyranoside; conversely, calotropin significantly decreased by 72%. ASE exerted antimutagenicity against PhIP, MelQ, and MelQx in TA98 and TA100 Salmonella strains, and this activity was not affected by heat, with the exception of MelQ (p < 0.05). Since HAAs can induce colorectal cancer, the thermal stability of ASE's antiproliferative effect against colorectal cancer cells was also evaluated. HT decreased (p < 0.05) the antiproliferative activity of ASE; however, the remaining activity was still strong with an IC50 of 16.8 ± 2.03 µg/mL. Therefore, ASE can be used as a food ingredient to reduce the carcinogenic potential of thermally induced HAAs.

Phenolic and triterpenoid composition and inhibition of α-amylase of pistachio kernels (Pistacia vera L.) as affected by rootstock and irrigation treatment.

The current water scarcity forces farmers to adopt new irrigation strategies to save water without jeopardizing the fruit yield and quality. In this study, the influence of 3 regulated deficit irrigation (RDI) treatments and 3 rootstocks on the functional quality of pistachios were studied. The functional parameters studied included, polyphenols, triterpenoids, and inhibition of α-amylase. The results showed that P. terebinthus and P. atlantica rootstocks led to pistachio kernels with higher contents of polyphenols and triterpenoids (mainly betulinic acid with 111 and 102 µg g-1, respectively) than pistachios obtained using P. integerrima rootstock (81 µg g-1). On the other hand, the use of moderate RDI (T1 treatment) increased the total content of polyphenols (∼10%), quercetin-O-galloyl-hexoside (∼15%), keampferol-3-O-glucoside (∼19%), and polymeric procyanidins (∼20%), as compared to the control trees, resulting in pistachios with a better functional profile, lower economic cost and with a lesser environmental impact.

Antimicrobial activity of pomegranate peel extracts as affected by cultivar.

BACKGROUND: Some studies have reported that different parts of the pomegranate fruit, especially the peel, may act as potential antimicrobial agents and thus might be proposed as a safe natural alternative to synthetic antimicrobial agents. The high tannin content, especially punicalagin, found in pomegranate extracts, has been reported as the main compound responsible for such antimicrobial activity. Because the pomegranate peel chemical composition may vary with the type of cultivar (sweet, sour-sweet and sour), pomegranates may also differ with respect to their antimicrobial capacity. RESULTS: The extract from PTO8 pomegranate cultivar peel had the highest antimicrobial activity, as well as the highest punicalagins (α and ß) and ellagic acid concentrations. In the results obtained from both antibacterial and antifungal activity studies, the sour-sweet pomegranate cultivar PTO8 showed the best antimicrobial activity, and the highest ellagic acid concentrations. CONCLUSION: The results of the present study suggest that ellagic acid content has a significant influence on the antimicrobial activity of the pomegranate extracts investigated. The pomegranate peel of the PTO8 cultivar is a good source of antifungal and antibacterial compounds, and may represent an alternative to antimicrobial agents of synthetic origin. © 2016 Society of Chemical Industry.

Antimutagenic Compounds of White Shrimp (Litopenaeus vannamei): Isolation and Structural Elucidation.

According to the World Health Organization, cancer is the main cause of mortality worldwide; thus, the search of chemopreventive compounds to prevent the disease has become a priority. White shrimp (Litopenaeus vannamei) has been reported as a source of compounds with chemopreventive activities. In this study, shrimp lipids were extracted and then fractionated in order to isolate those compounds responsible for the antimutagenic activity. The antimutagenic activity was assessed by the inhibition of the mutagenic effect of aflatoxin B1 on TA98 and TA100 Salmonella tester strains using the Ames test. Methanolic fraction was responsible for the highest antimutagenic activity (95.6 and 95.9% for TA98 and TA100, resp.) and was further separated into fifteen different subfractions (M1-M15). Fraction M8 exerted the highest inhibition of AFB1 mutation (96.5 and 101.6% for TA98 and TA100, resp.) and, after further fractionation, four subfractions M8a, M8b, M8c, and M8d were obtained. Data from (1)H and (13)C NMR, and mass spectrometry analysis of fraction M8a (the one with the highest antimutagenic activity), suggest that the compound responsible for its antimutagenicity is an apocarotenoid.

Bioactive Lipidic Extracts from Octopus (Paraoctopus limaculatus): Antimutagenicity and Antiproliferative Studies.

Fractions from an organic extract from fresh octopus (Paraoctopus limaculatus) were studied for biological activities such as antimutagenic and antiproliferative properties using Salmonella tester strains TA98 and TA100 with metabolic activation (S9) and a cancer cell line (B-cell lymphoma), respectively. A chloroform extract obtained from octopus tentacles was sequentially fractionated using thin layer chromatography (TLC), and each fraction was tested for antimutagenic and antiproliferative activities. Organic extract reduced the number of revertants caused by aflatoxin B(1) showing a dose-response type of relationship. Sequential TLC fractionation of the active extracts produced several antimutagenic and/or antiproliferative fractions. Based on the results obtained, the isolated fractions obtained from octopus contain compounds with chemoprotective properties that reduce the mutagenicity of AFB(1) and proliferation of cancer cell lines.

In vitro antioxidant and antiproliferative activities of plants of the ethnopharmacopeia from northwest of Mexico.

BACKGROUND: The aim of this study, is to investigate the in vitro antioxidant activity, the total phenols content, the flavonoids content and the antiproliferative activity of methanolic extracts of the plants: Krameria erecta, Struthanthus palmeri, Phoradendron californicum, Senna covesii and Stegnosperma halimifolium, used by different ethnic groups from northwestern Mexico in the treatment and cure of various diseases. METHODS: The in vitro antioxidant activity was measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and Ferric Reducing/Antioxidant Power assay (FRAP), the total phenols content was measured by Folin-Ciocalteau assay, the flavonoids content by the AlCl(3) colorimetric method and the antiproliferative activity (line cells HeLa, RAW 264.7, M12A(k).C3.F6 and L929) using MTT method. RESULTS: The K. erecta extract showed the higher radical scavenging activity (67.88%), antioxidant activity by FRAP (1.41 mg Trolox Eq), the highest total phenols content (598.51 mg Galic Acid Eq/g extract), the highest flavonoids content (3.80 mg Quercetin Eq/g extract) and the greatest antiproliferative activity in a dose dependent manner against most Cell line evaluated. A positive correlation was found between the antioxidant activity and the flavonoids content. CONCLUSIONS: This study is the first report on the antioxidant and antiproliferative activities of the five species evaluated. The results demostrate that there is a positive correlation between antioxidant activity and the flavonoids content, indicating that these type of polyphenols could be the major contributors to the observed antioxidant activity in the evaluated plant extracts. Of the extracts evaluated, that of Krameria erecta showed the greatest antioxidant and antiproliferative activities, a discovery that makes this species a promising candidate for future research.