Isolation and structural elucidation of antiproliferative compounds of lipidic fractions from white shrimp muscle (Litopenaeus vannamei)

In vitro evaluation of cytotoxic effects of di (2-ethylhexyl) phthalate (DEHP) produced by Bacillus velezensis strain RP137 isolated from Persian Gulf

Phthalates are widely used in polymer science and have potential toxicity related to their chemical structures. However, lots of evidence indicate that phthalate derivatives are undoubtedly produced as secondary metabolites by organisms, including plants, animals, and microorganisms. In the present study, Bacillus velezensis strain RP137 was cultured under optimized conditions. Its biomass was extracted with ethyl acetate with one fraction showing cytotoxic properties. A pure compound was isolated from the active fraction using combined silica gel and LH20 size exclusion column chromatography. Structural evaluation including FT-IR, ¹H NMR, ¹³C NMR, HR-MS and CHN analysis identified the purified compound as di(2-ethylhexyl)phthalate (DEHP) with the formula C₂₄H₃₈O₄ and the molecular weight of 389.29 Da. The microorganism-derived (stereospecific) DEHP was strongly reduced the proliferation and induced cytotoxic effects on various eukaryotic cell lines in compare to the synthetic racemic mixture of the compound when assessed by MTT assay. Furthermore, crystal violet assay and morphological changes confirmed the cytotoxic effect of DEHP. Interestingly, non-malignant SV40-immortalized fibroblast cells were less affected by the purified DEHP. Further evaluation on the antibacterial activity of DEHP documented no effect toward Gram-positive (S. aureus) and Gram-negative (E. coli and P. aeruginosa) pathogens even at a high concentration of 100 μM. In conclusion, existence of DEHP as byproduct of microorganism's metabolism can seriously be considered as a warning to human health.

Bioactive natural derivatives of phthalate ester

The advantages and emergent interest in organism-derived bioactive molecules have recently renewed scientific research attention in this field. Since 1967, about 52 different derivatives of phthalate ester (PE) have been reported from different taxonomic groups. Anthropogenic derivatives of the PEs are confined to petroleum products, as a plasticizer. These derivatives exhibit a potential toxicity on the living system, particularly those having a reduced molecular weight. An organism-derived PE differs chemically from that of synthetic ones in terms of the abundance of ¹⁴C and its bond structure, leading to its varied activities in the biological system. The study of the biosynthetic pathway and the optimization of parameters for product enhancement have advocated their organism-derived nature. Various bioactivities of such organisms-derived derivatives of phthalates such as antibacterial, antifungal, an inducer of apoptosis and cell cycle arrest, antioxidant, cytotoxic, antitumor, allopathic, larvicidal, antifouling, chemotactic, antimelanogenic, antiviral, and anti-inflammatory activities have been well documented. This is the first review that focuses on the positive bioactivities of such organism-derived PEs in detail. There is enormous scope for research in this field to search for the utilization of such organism-derived phthalate derivatives will have potential bioactivity, their possible use to improve their efficacy.

Antiproliferative activity of buttermilk lipid fractions isolated using food grade and non-food grade solvents on human cancer cell lines

Buttermilk is a dairy by-product with a high content of milk fat globule membranes (MFGMs), whose protein constituents are reported to be antiproliferative. Lipids represent about half of the composition of MFGM. The aim of this study was to isolate buttermilk lipid fractions and evaluate their potential antiproliferative effect. Selective extraction with food grade or non-food grade solvents was performed. Antiproliferative effectiveness of lipid extracts and their neutral and polar fractions was evaluated on nine human cancer cell lines. Fractions obtained using food grade ethanol gave a higher yield than those obtained using non-food grade solvents, and they effectively inhibited cell viability of the cancer cell lines investigated. These fractions, rich in phospho- and sphingolipids, were strongly antiproliferative against human ovary and colon cancer cells. This observation allowed us to hypothesize further analyses aimed at promoting the use of buttermilk polar lipid fractions as functional food additives.

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.