ABSTRACT
Prebiotic fructooligosaccharides (FOS) are currently obtained by enzymatic reaction with fructosyltransferases (FTFs) using sucrose as both donor and acceptor. In these reactions glucose results as the most abundant by-product, arising from each fructosyl transfer event and, together with fructose, because of the inherent hydrolytic activity of the FTFs. As FOS are mainly used as prebiotic in nutraceutical foods, the reduction or total elimination of monosaccharides is required. In this work the selective elimination of monosaccharides from a synthetic FOS mixture was achieved through the selective complexation of glucose and fructose with phenyl boronic acid (PBAc) followed by ethyl-acetate extraction. The process was applied to a complex mixture of FOS obtained in an enzymatic synthesis reaction containing 40% glucose, 15.8% fructose and 35% of FOS, elimination of the sugars was achieved through 3:1 molar reactions, resulting in a levan-type FOS product with 97% purity.
Subject(s)
Boronic Acids/metabolism , Monosaccharides/metabolism , Oligosaccharides/isolation & purification , Acetates/chemistry , Boronic Acids/chemistry , Chromatography, Thin Layer , Escherichia coli/metabolism , Fructose/chemistry , Glucose/chemistry , Glycoside Hydrolases/genetics , Glycoside Hydrolases/metabolism , Hexosyltransferases/genetics , Hexosyltransferases/metabolism , Liquid-Liquid Extraction , Monosaccharides/chemistry , Oligosaccharides/chemistry , Oligosaccharides/metabolism , Prebiotics/analysis , Recombinant Fusion Proteins/biosynthesis , Recombinant Fusion Proteins/geneticsABSTRACT
Despite prevention and treatment options, breast cancer (BC) has become one of the most important issues in the present day. Therefore, the need for more specific and efficient compounds remains paramount. We evaluated four previously isolated aryltetralin lignans: 5'-demethoxy-ß-peltatin-A-methylether (1), acetylpodophyllotoxin (2), 5'-demethoxydeoxypodophyllotoxin (3), and 7',8'-dehydroacetylpodophyllotoxin (4) for cytotoxicity, clonogenicity, and selectivity against three BC cell lines: MCF-7, MDA-MB-231, and BT-549, as well as the non-tumorigenic mammary epithelial cell line MCF-10A. Cytotoxicity was evaluated after 72 h of treatment, and clonogenicity was determined at 72 h post-treatment; experiments were performed using the sulforhodamine B staining assay. Selective-index (SI) was calculated by comparing pure compound IC50 values in MCF-10A cell line against the IC50 of the same compound in cancer cell lines. Structural similarities among lignans and controls (podophyllotoxin and etoposide) were analyzed using the Tanimoto coefficient (Tc). Lignans were cytotoxic against all tested cell lines (0.011-7.22 µM) and clonogenicity testing showed a dose-dependent cytocidality for all lignans (≥0.08 µg/mL); compounds 2 and 3 were more potent (14.1 and 7.6 respectively) than etoposide in BT-549 cell line, while compound 2 displayed selectivity (SI = 28.17) in BT-549 cell line. Tc values of lignans suggested a greater similarity with podophyllotoxin structure.
Subject(s)
Antineoplastic Agents, Phytogenic/pharmacology , Bursera/chemistry , Lignans/pharmacology , Plant Extracts/chemistry , Antineoplastic Agents, Phytogenic/chemistry , Breast Neoplasms/drug therapy , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , Dose-Response Relationship, Drug , Female , Humans , Lignans/chemistry , MCF-7 Cells , Molecular Structure , Podophyllotoxin/chemistry , Podophyllotoxin/pharmacologyABSTRACT
BACKGROUND: Cancer is one of the leading causes of death worldwide. Natural products have been regarded as important sources of potential chemotherapeutic agents. In this study, we evaluated the anti-proliferative activity of Argemone gracilenta's methanol extract and its fractions. We identified those compounds of the most active fractions that displayed anti-proliferative activity. METHODS: The anti-proliferative activity on different cancerous cell lines (M12.C3F6, RAW 264.7, HeLa) was evaluated in vitro using the MTT colorimetric method. Identification of the active compounds present in the fractions with the highest activity was achieved by nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS) analyses. RESULTS: Both argemonine and berberine alkaloids, isolated from the ethyl acetate fraction, displayed high anti-proliferative activity with IC50 values of 2.8, 2.5, 12.1, and 2.7, 2.4, 79.5 µg/mL on M12.C3F6, RAW 264.7, and HeLa cancerous cell lines, respectively. No activity was shown on the normal L-929 cell line. From the hexane fraction, a mixture of fatty acids and fatty acid esters of 16 or more carbon atoms with anti-proliferative activity was identified, showing a range of IC50 values of 16.8-24.9, 34.1-35.4, and 67.6-91.8 µg/mL on M12.C3F6, RAW 264.7, and HeLa cancerous cell lines, respectively. On the normal L-929 cell line, this mixture showed a range of IC50 values of 85.1 to 100 µg/mL. CONCLUSION: This is the first study that relates argemonine, berberine, and a mixture of fatty acids and fatty acid esters with the anti-proliferative activity displayed by Argemone gracilenta.