Food Protein Sterylation: Chemical Reactions between Reactive Amino Acids and Sterol Oxidation Products under Food Processing Conditions

Sterols, especially cholesterol and phytosterols, are important components of food lipids. During food processing, such as heating, sterols, like unsaturated fatty acids, can be oxidized. Protein modification by secondary products of lipid peroxidation has recently been demonstrated in food through a process called lipation. Similarly, this study was performed to assess, for the first time, the possibility of reactions between food proteins and sterol oxidation products in conditions relevant for food processing. Therefore, reaction models consisting of oxysterol (cholesterol 5,6-epoxide) and reactive amino acids (arginine, lysine, and methionine) were incubated in various conditions of concentration (0–8 mM), time (0–120 min), and temperature (30–180 C). The identification of lysine adducts through thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC) with a diode array detector (DAD), and electrospray ionization (ESI) mass spectrometry (MS) evidenced a reaction with lysine. Moreover, the HPLC-ESI with tandem mass spectrometry (MS/MS) analyses allowed observation of the compound, whose mass to charge ratio m/z 710.5 and fragmentation patterns correspondedto the reactionproduct [M+H]+ between cholesterol-5,6-epoxide andthe "-amino-group of N-benzoylglycyl-l-lysine. Moreover, kinetic studies between N-benzoylglycyl-l-lysine as a model for protein-bound lysine and cholesterol 5,6-epoxide were performed, showing that the formation of lysine adducts strongly increases with time, temperature, and oxysterol level. This preliminary study suggests that in conditions commonly reached during food processing, sterol oxidation products could react covalently with protein-bound lysine, causing protein modifications

CHEMICAL COMPOSITION OF TEN ESSENTIAL OILS FROM CALOPHYLLUM INOPHYLLUM LINN AND THEIR TOXICITY AGAINST ARTEMIA SALINA

Essential oils from ten different parts of Calophyllum inophyllum were analyzed by Gas Chromatography-Mass Spectrometry (GC-MS) to study their chemical compositions. The yields were between 0.219 and 0.506 %. A total of 102 compounds were identified in the ten C. inophyllum essential oils, which are mostly monoterpenes, sesquiterpenes and their oxygenated derivatives. The numbers and percentages of identified compounds varied in the different parts of the plant: leaf (71, 54.94%), leaf stalk (22, 79.55%), flower (25, 51.24%), seed (25, 89.39%), seed-coat (69, 73.80%) fruit-pulp (15, 46.10%), stem wood (55, 59.40%), stem bark (9, 69.38%) root wood (51, 58.73%), and root bark (24, 74.66%). High content of cymene, terpinene, and limonene in the oils may be responsible for the vast ethno-medicinal applications of the plant. Toxicity experiments show that the oils were fairly toxic. Each part after 24 hours of exposure against Artemia salina gave the following LC50 values in μg/mL: leaf (68.8740 μg/mL), leaf-stalk (102.5692 μg/mL), flower (114.4410 μg/mL), seed (132.2324 μg/mL), seed coat (137.1206 μg/mL), fruit-pulp (135.0350 μg/mL) stem wood (126.1410 μg/mL), stem bark (149.7237 μg/mL), root wood (110.6539 μg/mL) and root bark (110.6539 μg/mL). The chemical compositions and toxicity levels of these ten Calophyllum inophyllum essential oils are reported for the first time in literature

Polyphenols, Saponins and Phytosterols in Lentils and Their Health Benefits: An Overview

The lentil (Lens culinaris L.) is one of the most important legumes (family, Fabaceae). It is a natural functional food rich in many bioactive compounds, such as polyphenols, saponins and phytosterols. Several studies have demonstrated that the consumption of lentils is potentially important in reducing the incidence of a number of chronic diseases, due to their bioactive compounds. The most common polyphenols in lentils include phenolic acids, flavan-3-ol, flavonols, anthocyanidins, proanthocyanidins or condensed tannins, and anthocyanins, which play an important role in the prevention of several degenerative diseases in humans, due to their antioxidant activity. Furthermore, lentil polyphenols are reported to have antidiabetic, cardioprotective and anticancer activities. Lentil saponins are triterpene glycosides, mainly soyasaponins I and βg. These saponins have a plasma cholesterol-lowering effect in humans and are important in reducing the risk of many chronic diseases. Moreover, high levels of phytosterols have been reported in lentils, especially in the seed coat, and β-sitosterol, campesterol, and stigmasterol are the most abundant. Beyond their hypocholesterolemic effect, phytosterols in lentils are known for their anti-inflammatory activity. In this review, the current information on the nutritional composition, bioactive compounds including polyphenols, saponins and phytosterols, and their associated health-promoting effects are discussed

Barrier properties, migration into the food simulants and antimicrobial activity of paper-based materials with functionalized surface

The study investigates four paper-based materials designed for short-time wrapping of meat products by determining morpho-structure, capillary-hydroscopic, barrier and antibacterial properties, wettability and migration into food simulants. The paper-based materials are coded as RO, SP, IT and SLO. RO and SLO samples exhibit the best barrier properties against water vapors. The low solubility and contact angles of RO, IT and SLO in A simulant (distilled water) make them suitable for aqueous food storage. The extremely high solubility of SP and SLO in simulant B (acetic acid) shows that wax and hydrophobized starch, respectively are carried by the acidic media, thus these agents are unlikely to coat the paper designed to package acidic food. SLO inhibits E. coli, Salmonella enterica, Lysteria monocytogenes, Pseudomonas aeruginosa and fluorescens. Polyethylene coated on RO and IT surface and wax impregnated on SP have a lower antimicrobial activity in comparison with hydrophobized starch coated on SLO

Franks kamgang Nzekoue, Giovanni Caprioli, Sauro Vittori, Gianni Sagratini

Among the chronic diseases related to the human diet, cardiovascular disease, which is associated to high levels of total cholesterol, is one of the most leading cause of death in the world [1]. Nowadays, the growing consumer awareness of their blood cholesterol level, has guided the food industry to respond by proponing new food products, which could satisfy consumer expectations. Therefore, during the recent years, the development of low-fat food products has considerably increased especially in the dairy sector. Another strategy has consisted to develop functional dairy products (F.D.P) containing phytosterols, which are steroid compounds occurring in plants and having a lowering effect on blood LDL-cholesterol [2]. This development of new functional food (F.F) is an interconnected process involving food industry companies, European commission regulations, marketing and scientists [3]. In this regard, researchers from the University of Camerino and a cheese producing company named SABELLI have come together to produce a new phytosterols-enriched ricotta cheese. To our knowledge, it is the first time that a ricotta cheese enriched in phytosterols is developed. The process leading to this new F.D.P has been a complex pathway with many challenges. Thus, the present report aims to show step by step all the food chemistry studies performed to realize this product. To obtain this F.F, we started by a) studying the nutritional composition of ricotta in order to assess its possible health claims; then, we have to challenge b) the development and the validation of a new low-cost and fast analytical method for phytosterols quantification using high performance liquid chromatography-diode array detector (HPLC-DAD). However, due to their lack of chromophore group and their low ionization in mass spectrometry (MS), we have to innovate by developing a new derivatization method using dansyl chloride which allowed to detect plants sterols and stanols at 254 nm in DAD and highly increased their ionization in MS. The third step consisted to c) study the composition and the stability of phytosterols ingredients during ricotta production and storage. After validation, we finally d) studied different formulations for ricotta enrichment and assessed the effect of this enrichment on the organoleptic properties and the quality of the ricotta after its production and during its shelf-life. These studies illustrate in a practical way, the crucial role of food chemistry in functional foods development and therefore, the impact of this research field in the food industry growth and the improvement of the human health

Development of new HPLC MS/MS method for the simultaneous quantification of sixteen polyphenols in pulses.

Introduction: Pulses are among the most important dietary component worldwide, demonstrating cardioprotective, hypolipidemic [1] and antioxidant activities [2]. These health benefits could be attributed to their content in polyphenols [3]. Thus, this work aims to develop a HPLC-MS/MS method to simultaneously detect and quantify 16 polyphenols in different kind of pulse. Methods: The polyphenols analyzed by HPLC-MS-MS were: shikimic acid, gallic acid, delphinidin, catechin, chlorogenic acid, epicatechin, vanillic acid, caffeic acid, siringic acid, cumaric acid, ferulic acid, 3,5 di-CQA, rutin, kaempferol, cyanidin, quercetin. Moreover, many extraction procedures such as acidic and basic hydrolysis were compared by combining different temperatures and extraction times. Results: The best extraction recoveries (range 99.7- 107.6%) were obtained in acidic conditions at pH 2 with a temperature of 20o C and an extraction time of 2h. The newly developed analytical method is fast as polyphenols elute within 10 minutes. The method implied Dynamic MRM that allowed to quantify simultaneously a number of compound assuring excellent linearity and sensitivity. Analytes are only monitored while they are eluting from the LC and valuable MS duty cycle is not wasted by monitoring them when they are not expected. This validated method was applied on thirty one pulse samples including beans, lentils, peas and chickpeas. The highest polyphenols levels were found in beans such as black beans (458.64 mg/kg) and ruviotto beans (189.02 mg/kg); also lentils displayed consistent level of polyphenols, such as black lentils (137.25 mg/kg) and quality gold lentils (132.27 mg/kg). Conclusions: A new analytical method that uses HPLC-MS/MS was developed for the analysis of sixteen polyphenols in pulses. This study highlights that certain polyphenols are characteristic in specific pulses variety and this aspect may be useful for increasing the health knowledge of legumes and for proposing new functional foods. References 1. J. Anderson, A. W. Major. British Journal of Nutrition, 88 (3), 263-271(2002). 2. C. A. Adebamowo, E. Cho, L. Sampson, M. B. Katan, D. Spiegelman, W. C. Willett, M. C. Holmes. International Journal of Cancer, 114, 628-633 (2005). 3. Lazze, M.C., Pizzala, R., Savio, M., Stivala, L.A., Prosperi, E., Bianchi, L. Mutation Research/Genetic Toxicology and Environmental Mutagenesis, 535, 103-115 (2003)

Conversion of ergosterol into vitamin D2 and other photoisomers in Agaricus bisporus mushrooms under UV-C irradiation

Agaricus bisporus mushrooms contain high levels of ergosterol (3–8 mg/g dw), which can be converted into vitamin D2 (VD2) under ultraviolet irradiation (UV). However, the photoconversion of ergosterol can also lead to the production of inactive photoisomers decreasing the production yield of VD2. This study assesses the impact of UV irradiation conditions on the conversion of ergosterol into vitamin D2. The effects of various parameters were tested including the mushroom form (powder, extract, suspension), irradiation time (0–240 min), temperature (20–40◦C), intensity (0.16–0.48 mW/cm2), and agitation during UV-C irradiation. The mushroom extract was the most suitable mushroom form for VD2 production. Beyond VD2, other photoisomers (tachysterol and lumisterol), were detected through HPLC-APCI-MS and their levels increased with deep and prolonged irradiation. The highest VD2 levels (0.95–1.03 mg/g dw) were obtained by irradiating mushroom extracts with an intensity of 0.31 mW/cm2 for 10 min. These results highlight the potential of mushrooms for VD2 production through UV-C irradiation, which is accompanied by the formation of biologically-active photo-isomers

Development of a functional whey cheese (ricotta) enriched in phytosterols: Evaluation of the suitability of whey cheese matrix and processing for phytosterols supplementation

This study aims to evaluate the suitability of whey cheese (ricotta) and whey cheese production process for phytosterols-enrichment. Therefore, the phytosterols stability of ricotta cheese was assessed during cheese processing (85 ◦C for 60 min) and storage (4 ◦C for 4 weeks). Given the novelty of the food matrix used, it was necessary to develop an innovative analytical method for sterols determination in enriched ricotta cheese. The developed HPLC-DAD method showed good linearity (R2 ≥ 0.9956) and reproducibility (0.4–7.6%), while extraction recoveries ranged between 83.7% and 84.6%. Phytosterols showed a good heat-stability in ricotta cheese matrix during cheese processing (87.0–89.7) %. Moreover, the functional cheese showed a homogeneous phytosterols distribution and maintained its potential bioactivity during its shelf-life since no significant variation of phytosterols levels was observed during storage (0.83 ± 0.03) g/100 g