Nanoencapsulation of Jania rubens seaweeds' antioxidants for food applications

Abstract

An additive for food products to extend shelf-life is provided where the additive is nanoparticles having extracted phytochemicals or anti-oxidants from Jania Rubens nano-encapsulated with chitosan-tripolyphosphate. Shelf-life was extended in contrast to the synthetic preservatives which are typically used in the food industry. The cost of the natural preservative is much less than that of the synthetic preservatives. Extension of shelf-life by a natural source is nowadays more desirable by the consumers due to the modem trends of consumption of food with no chemical preservatives.

Claims

1. An additive for food products to extend shelf-life, comprising: nanoparticles having extracted phytochemicals or anti-oxidants from Jania Rubens nano-encapsulated with chitosan-tripolyphosphate.

2. The additive as set forth in claim 1, wherein the phytochemicals or anti-oxidants are polyphenols and flavonoids.

3. A method of extending shelf-life of food products, comprising: (a) having nanoparticles having extracted phytochemicals or anti-oxidants from Jania Rubens nano-encapsulated with chitosan-tripolyphosphate; and (b) adding the nanoparticles to a food product.

4. The method as set forth in claim 1, wherein the food products are corn oil, sunflower oil, soybean oil or palm oil.

5. The method as set forth in claim 1, wherein the phytochemicals or anti-oxidants are polyphenols and flavonoids.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1 shows according to an exemplary embodiment of the invention a schematic presentation showing the cross-linking between the chitosan polymer and the Algal extract. The schematic presentation on the right shows the chitosan-tripolyphosphate (TPP) shell encapsulating the Jania Rubens algal extract. JCNP stands for Jania Rubens chitosan nanoparticles. 110=chitosan; 120=chitosan amino groups; 130=chitosan functional groups; 140=Jania Rubens algal extract; 150=Mixing step (mixing of the chitosan and algal extract solutions by agitation with a magnetic stirrer); 160=solution of chitosan and Jania Rubens algal extract; 170=sodium tripolyphosphate; 180=Homogenization (by means of a high pressure homogenizer to produce monodisperse small nanoparticles); 190=Chitosan-tripolyphosphate encapsulating the Jania Rubens algal extract.

[0010] FIGS. 2A-D show according to an exemplary embodiment of the invention extension of the shelf-life of oils expressed as primary oxidation products (peroxide value) versus time of storage in sunflower (FIG. 2A), corn (FIG. 2B), soybean (FIG. 2C) and palm oil (FIG. 2D), respectively. Orange 210oil with synthetic antioxidant, green 220oil with chitosan nanoparticles encapsulation the Jania Rubens extract, grey 230oil with raw extract, blue 240oil with pristine chitosan nanoparticles, yellow 250oil with no additives.

[0011] FIGS. 3A-D show according to an exemplary embodiment of the invention extension of the shelf life of oils expressed as secondary oxidation products (thiobarbituric acid value) versus time of storage in sunflower (FIG. 3A), corn (FIG. 3B), soybean (FIG. 3C) and palm oil (FIG. 3D), respectively. Orange 310oil with synthetic antioxidant, green 320oil with chitosan nanoparticles encapsulation the Jania Rubens extract, grey 330oil with raw extract, blue 340oil with pristine chitosan nanoparticles, yellow 350oil with no additives.

DETAILED DESCRIPTION

[0012] Jania Rubens

[0013] Jania Rubens is available throughout the different seasons in the shores by e.g. Alexandria, Egypt. Jania Rubens is rich in many vital bioactive compounds including flavonoids, diterpenes, carotenoids, vitamins, fatty acids, tannins, phytol, and many more secondary metabolites. The major classes of polyphenols have been found to be flavonoids and tannins, which are known to process an antioxidant activity. To date, a minute amount of research has been done on this specific seaweed.

[0014] Antioxidants Extracted from Jania Rubens

[0015] The antioxidant efficacy of the Jania Rubens algal extract has been shown to be high by means of two antioxidants assays, i.e., 2,2-diphenyl-1-picrylhydrazyl, ferric reducing antioxidant power. Total phenolic content and total flavonoid content assays were carried out and both assays showed that the algal extract is rich in polyphenols and flavonoids, which are potent antioxidants. Diverse phytochemicals which possess an antioxidant activity were isolated from Jania Rubens by using gas chromatography-mass spectrometry and liquid chromatography-mass spectrometry. The Jania Rubens' extract revealed abundance of fatty acids, e.g. syringic acid, benzene dicarboxylic acid, myristic acid, palmitelaidic acid, palmitic acid, heptadecanoic acid, dodecanoic acid, oleic acid, stearic acid, octanoic acid, itaconic acid, adipic acid, glycolic acid and arachidic acid, which exhibit an antioxidant activity. In addition to fatty acids, some alcohols were detected that exhibit an antioxidant activity e.g. 1,4-butanediol, diethylene glycol and glycerol. Several nitrogenous compounds were detected most of which exhibit an antioxidant effect including uracil, 1-propionylproline, pyrrolidine, 2-butyl-1-methyl, 3-pyridinol and 3-hydroxypicolinic acid. Detected sugars, which have an antioxidant effect, included galactopyranose, 2-O-glycerol-?-d-galactopyranoside and D-glucose. Other lypophilic metabolites identified with a potential antioxidant effect included phytol and neophytadiene. Table 1 below shows the algal phytochemicals detected by gas chromatography-mass spectrometry. Table 2 below shows the algal phytochemicals detected by liquid chromatography-mass spectrometry.

[0016] Examples of phytochemicals or anti-oxidants from Jania Rubens useful to be nano-encapsulated with chitosan-tripolyphosphate are, for example, polyphenols, flavonoids, phytol, neophytadiene, syringic acid, benzene dicarboxylic acid, myristic acid, palmitelaidic acid, palmitic acid, heptadecanoic acid, dodecanoic acid, oleic acid, stearic acid, octanoic acid, itaconic acid, adipic acid, glycolic acid, arachidic acid, 1,4-butanediol, diethylene glycol, glycerol, uracil, 1-propionylproline, pyrrolidine, 2-butyl-1-methyl, 3-pyridinol, 3-hydroxypicolinic acid, galactopyranose, 2-O-glycerol-?-d-galactopyranoside, or D-glucose, or any combination thereof. In one embodiment, polyphenols and flavonoids are recognized as the key phytochemicals or anti-oxidants from Jania Rubens useful to be nano-encapsulated with chitosan-tripolyphosphate. In another embodiment, at least polyphenols and flavonoids are recognized as the phytochemicals or anti-oxidants from Jania Rubens useful to be nano-encapsulated with chitosan-tripolyphosphate.

[0017] Encapsulation of Characterized Antioxidants

[0018] To further enhance the Jania Rubens' extract's efficacy, the algal extracts (i.e. antioxidants) were nanoencapsulated into chitosan-tripolyphosphate nanoparticles using an ionic gelation technique via high pressure homogenization. The optimum nanoformulation was characterized by scanning electron microscopy and transmission electron microscopy. The nanoformulation had a particle size of 161 nm, zeta potential of 31.2 my, polydispersity index of 0.211 and an entrapment efficiency of 99.7%. FIG. 1 shows a schematic presentation showing the cross-linking between the chitosan polymer and the Algal extract. The schematic presentation on the right shows the chitosan-tripolyphosphate shell encapsulating the Jania Rubens algal extract.

[0019] Shelf-Life

[0020] The nanoencapsulated Jania Rubens extracted antioxidant were added to oils to extend their shelf-life. The ability of the nanoparticle to extend the shelf-life of vegetable oils, corn, sunflower, soybean, and palm oils, was based on peroxide value and thiobarbituric acid assays. Additionally, headspace solid-phase microextraction was applied to detect the oils' volatiles as secondary markers of rancidity. The results revealed that the nanoencapsulated Jania Rubens' extract considerably reduced the rate of formation of the primary and secondary oxidation products in the oils. In other words, the nanoencapsulated Jania Rubens' extract extended the shelf life of the oils to a big extent, besides that its activity was comparable to that of a widely used synthetic antioxidant butylated hydroxytoluene.

[0021] FIGS. 2A-D show the extension of the shelf-life of oils expressed as primary oxidation products (peroxide value) versus time of storage in sunflower (FIG. 2A), corn (FIG. 2B), soybean (FIG. 2C) and palm oil (FIG. 2D), respectively. Orange 210oil with synthetic antioxidant, green 220oil with chitosan nanoparticles encapsulation the Jania Rubens extract, grey 230oil with raw extract, blue 240oil with pristine chitosan nanoparticles, yellow 250oil with no additives.

[0022] FIGS. 3A-D show the extension of the shelf life of oils expressed as secondary oxidation products (thiobarbituric acid value) versus time of storage in sunflower (FIG. 3A), corn (FIG. 3B), soybean (FIG. 3C) and palm oil (FIG. 3D), respectively. Orange 310oil with synthetic antioxidant, green 320oil with chitosan nanoparticles encapsulation the Jania Rubens extract, grey 330oil with raw extract, blue 340oil with pristine chitosan nanoparticles, yellow 350oil with no additives.

TABLE-US-00001 TABLE 1 The algal phytochemicals detected by gas chromatography-mass spectrometry Retention Molecular Peak # time (min) KI Area Compound name formula 1 7.05 1084.7 1152 Glycolic acid, 2TMS C.sub.2H.sub.4O.sub.3 2 8.61 1173.2 874 Acetic acid CH.sub.3COOH 3 9.76 1242.2 1306 4-Hydroxybutanoic acid C.sub.4H.sub.8O.sub.3 4 10.17 1268.8 1424 Octanoic acid, TMS ester C.sub.8H.sub.16O.sub.2 5 11.57 1360.2 1782 Itaconic acid, 2TMS C.sub.5H.sub.6O.sub.4 6 13.68 1512.6 897 Adipic acid, 2TMS C.sub.6H.sub.10O.sub.4 7 14.27 1557.8 692 Cinnamic acid C.sub.9H.sub.8O.sub.2 8 15.48 1654.6 714 Dodecanoic acid C.sub.12H.sub.24O.sub.2 9 8.55 1168.8 3084 1,4-Butanediol C.sub.4H.sub.10O.sub.2 10 9.91 1252.2 1084 Diethylene glycol, 2TMS C.sub.4H.sub.10O.sub.3 11 10.42 1285.6 7270 Glycerol, 3TMS C.sub.3H.sub.8O.sub.3 12 7.47 1108.2 1182 3,4,5-Trimethylheptane C.sub.10H.sub.22 13 16.02 1699.8 3232 Heptadecane C.sub.17H.sub.36 14 15.41 1648.4 961 4-Acetamido-1-phenylpyrazole C.sub.11H.sub.11N.sub.3O 15 17.72 1849.1 1591 Myristic acid, TMS C.sub.14H.sub.28O.sub.2 16 18.77 1947.7 1334 Myristic acid, TMS C.sub.14H.sub.28O.sub.2 17 19.58 2026.7 17204 Palmitelaidic acid-TMS C.sub.18H.sub.34O.sub.2 18 19.77 2045.9 21646 Palmitic Acid-TMS C.sub.16H.sub.32O.sub.2 19 20.73 2144.8 452 Heptadecanoic acid, TMS C.sub.17H.sub.34O.sub.2 20 21.43 2218.9 2416 Oleic Acid-TMS C.sub.18H.sub.34O.sub.2 21 21.49 2225.3 1744 Oleic Acid-TMS C.sub.18H.sub.34O.sub.2 22 21.64 2242.8 2637 Stearic acid-TMS C.sub.18H.sub.36O.sub.2 23 23.37 2441.9 544 Arachidic acid-TMS C.sub.20H.sub.40O.sub.2 24 10.90 1316.3 1353 Unknown nitrogenous compound 25 11.33 1344.7 4306 Unknown nitrogenous compound 26 11.41 1349.8 1069 Uracil, 2TMS C.sub.4H.sub.4N.sub.2O.sub.2 27 12.52 1425 1451 Unknown nitrogenous compound 28 12.74 1442.1 3221 1-Propionylproline, TMS C.sub.8H.sub.13NO.sub.3 derivative 29 13.55 1502.9 1156 Unknown nitrogenous compound 30 23.76 2491.6 498 Unknown nitrogenous compound 31 7.60 115.6 962 2-Butyl-1-methylpyrrolidine C.sub.9H.sub.19N 32 8.12 1144.6 3372 3-Pyridinol, TMS C.sub.5H.sub.5NO 33 8.77 1181.0 1996 3-Hydroxypicolinic acid, 2TMS C.sub.6H.sub.5NO.sub.3 34 9.82 1246.4 1157 Urea, 2TMS CH.sub.4N.sub.2O 35 12.33 1411.2 757 Phloroglucinol, O,O- C.sub.6H.sub.6O.sub.3 bis(trimethylsilyl) 36 14.56 1579.3 1004 Unknown steroid, TMS 37 21.95 2276.9 1209 Unknown sterol, TMS 38 29.22 3182.4 3529 Cholesterol, TMS C.sub.27H.sub.46O 39 19.34 2001.3 559 Galactopyranose, 5TMS C.sub.6H.sub.12O.sub.6 40 21.88 2269.2 11343 O-Glycerol-?-galactopyranoside C.sub.27H.sub.66O.sub.8 41 16.32 1726.1 566 Levoglucosan, 3TMS C.sub.6H.sub.10O.sub.5 42 18.44 1916.8 470 D-Glucose, 6 TMS C.sub.6H.sub.12O.sub.6 43 17.62 1839.6 670 Neophytadiene C.sub.20H.sub.38 44 17.90 1865.2 506 Neophytadiene C.sub.20H.sub.38 45 21.03 2176.3 6862 Phytol, TMS derivative C.sub.20H.sub.40O

TABLE-US-00002 TABLE 2 The algal phytochemicals detected by liquid chromatography-mass spectrometry Peak Rt Molecular Error No (min) [M ? H]? Metabolite MS.sup.n ions (m/z) Formula (ppm) Class 1. 0.51 200.96 Dihydroxyphenyl 183, 157, 110, C.sub.9H.sub.11O.sub.5 3.76 Phenolics glycerol 89 2. 0.51 272.96 Dihydroxycoumarin 255, 237, 228, C.sub.9H.sub.5O.sub.8S 5.78 Coumarin sulfate 214, 200, 187 3. 0.58 197.81 Syringic acid 170, 168, 153, C.sub.9H.sub.9O.sub.5 2.76 Phenolics 135 4. 10.54 187.10 Laminine 169, 160, 142, C.sub.9H.sub.19N.sub.2O.sub.2 0.57 Betaine 125 5. 11.12 165.95 Benzenedicarboxylic 133, 122 C.sub.8H.sub.5O.sub.4 3.15 Aromatic acid acid 6. 11.86 277.91 Syringic acid sulfate 197,165, 137 C.sub.9H.sub.9O.sub.8S 0.26 Phenolics 7. 13.38 242.18 Pentadecanoic acid 225, 198, 181 C.sub.15H.sub.29O.sub.2 ?1.63 Fatty acid 8. 14.89 323.22 Hydroxyeicosadienoic 305, 279, 197, C.sub.20H.sub.35O.sub.3 2.81 Fatty acid acid 183 9. 16.57 265.15 Heptadecadienoic acid 239, 221, 98 C.sub.17H.sub.29O.sub.2 1.92 Fatty acid 10. 17.04 297.15 Nonadecanoic acid 279, 253, 197, C.sub.19H.sub.37O.sub.2 0.62 Fatty acid 183 11. 17.53 311.17 Arachidic acid 293, 267, 197, C.sub.20H.sub.39O.sub.2 1.73 Fatty acid 183 12. 18.61 325.18 Arachidic acid methyl 296, 267, C.sub.21H.sub.41O.sub.2 2.04 Fatty acid ester 225, 197, 183 13. 19.25 339.20 Arachidic acid ethyl 311, 295, 239, C.sub.22H.sub.43O.sub.2 ?0.90 Fatty acid ester 183