Investigation of the Potential Use, Phytochemical and Element Contents of Acacia Plant Seeds Grown in Wild Form, Considered as Environmental Waste.

In this study, the effect of altitude on oil amounts, antioxidant activity, polyphenol content and mineral contents of Acacia seeds collected from two different locations (up to 1100 m above sea level) was investigated. Total carotenoid and flavonoid contents of Acacia seeds were detected as 0.76 (Konya) and 1.06 µg/g (Tasucu-Mersin) to 1343.60 (Konya) and 184.53 mg/100 g (Tasucu-Mersin), respectively. Total phenol contents and antioxidant activity values of Acacia seeds were identified as 255.11 (Konya) and 190.00 mgGAE/Tasucu-Mersin) to 64.18% (Konya) and 75.21% (Tasucu-Mersin), respectively. The oils extracted from Acacia seeds in Konya and Mersin province contained 62.70% and 70.39% linoleic, 23.41% and 16.03% oleic, 6.45%and 6.04% palmitic and 2.93% and 4.94% stearic acids, respectively. While 3,4-dihydroxybenzoic acid amounts of seeds are determined as 3.89 (Konya) and 4.83 mg/100 g (Tasucu-Mersin), (+)-catechin contents of Acacia seeds were identified as 3.42 (Konya) and 9.51 mg/100 g (Tasucu-Mersin). Also, rutintrihydrate and ferulic contents of Acacia seeds were found as 23.37 (Konya) and 11.87 mg/100 g (Tasucu-Mersin) to 14.74 mg/100 g (Konya) and 1.12 mg/100 g (Tasucu-Mersin), respectively. Acacia seeds collected from Konya and Mersin contained 4003.75 and 3540.89 mg/kg P, 9819.12 and 16175.69 mg/kg K, 4347.47 and 5078.81 mg/kg P, 2195.77 and 2317.90 mg/kg Mg, 1015.75 and 2665.60 mg/kg S and 187.53 and 905.52 mg/kg Na, respectively.

Influence of Drying Methods on Bioactive Properties,Fatty Acids and Phenolic Compounds of Different Parts of Ripe and Unripe Avocado Fruits.

All drying processes increased oil content, antioxidant activity, total phenolic contents, and most of the phenolic compounds in the pulp, peel and seeds of both ripe fruits with varied degrees (p < 0.05). In addition, the processes reduced the oil contents, linoleic acids, 3,4-dihydroxybenzoic acid, (+)-catechin, and naringenin of the pulp, antioxidant activity of the peels and seeds, and 3,4-dihydroxybenzoic acid, (+)-catechin of the seeds and it enhanced all other parameters in the pulp, peel, and seeds of unripe fruits (p < 0.05). Comparing the phenolic profiles of avocado pulp, peels, and seeds of ripe and unripe fruits indicated that the peel and seeds are richer than the pulp and that is superior in unripe fruits than ripe ones. In addition, drying processes particularly microwave and air drying greatly enhanced the bioactive properties of ripe and unripe avocado fruits and could thus be used to elongate the shelf-life of avocado fruit products without major impact on the overall quality.

Bioactive compounds, nutritional and sensory properties of cookies prepared with wheat and tigernut flour.

This study aimed to evaluate cookies made with wheat (0%, 80%, 60%, and 50%) and tigernut flour (0%, 20%, 40%, and 50%) from two different sources. Standard methods were applied to determine the chemical properties, phenolic component, fatty acid composition, mineral content, and sensory properties of cookies. Tigernut flour from both sources was rich in oil, and total and individual phenolics, but with low antioxidant activity compared to wheat flour. The addition of tigernut flour to wheat resulted in increase of the content of bioactive compounds, minerals, and fatty acid contents of cookies. The cookies produced by formulating wheat with tigernut had a comparable organoleptic quality scores to wheat flour cookies. The production of cookies with both wheat and tigernut flour showed that this mixture is an interesting opportunity to have a functional product rich in bioactive compounds and considered satisfactory by consumers.

Determination of Bioactive Lipid and Antioxidant Activity of Onobrychis, Pimpinella, Trifolium, and Phleum spp. Seed and Oils.

In this study, bioactive lipid components such as fatty acid composition, tocopherol and total phenolics content and antioxidant activity of few wild plant seed extracts were determined. The oil contents of seed samples changed between 3.75 g/100 g (Onobrychis viciifolia Scop) and 17.94 g/100 g (Pimpinella saxifrage L.). While oleic acid contents of seed oils change between 10.4% (Trifolium repens) and 29.5% (Onobrychis viciifolia Scop), linoleic acid contents of oil samples varied from 16.3% (Onobrychis viciifolia Scop) and 64.2% (Trifolium repens) (p < 0.05). While α-tocopherol contents of oil samples change between 2.112 (Pimpinella saxifrage L.) and 228.279 mg/100 g (Trifolium pratense), É£-tocopherol contents ranged from 0.466 (Phleum pratense) to 67.128 mg/100 g (Onobrychis viciifolia Scop). Also, α-tocotrienol contents of Onobrychis viciifolia Scop and Phleum pratense were 30.815 and 23.787 mg/100 g, respectively. Results showed some differences in total phenol contents and antioxidant activity values of extracts depending on plant species. The present study indicates that this seed oils are rich in fatty acid and tocopherol.

Influence of Thermal Processing on Oil Contents, Bioactive Properties of Melon Seed and Oils.

The oil content and the fatty acid composition of roasted and unroasted melon seed and oils were determined. The oil contents of roasted melon seeds changed between 26.4% (Type 12) and 38.7% (Type 4). In general, oil contents of roasted melon seeds were found higher than that of unroasted seeds that could be due to the evaporation of water during roasting processes which consequently lead to increased concentrations of other seed components including oils. Saturated fatty acid contents of unroasted melon seed samples change between 13.5% (Type 6) and 17.1% (Type 20). In addition, polyunsaturated fatty acids of unroasted melon seed oils ranged from 51.9% (Type 13) to 70.2% (Type 6). Palmitic acid contents of roasted seed oils varied between 7.8% (Type 5) and 15.1% (Type 17). In addition, the oleic acid contents ranged from 15.4% (Type 10) to 37.7% (Type17). Also, linoleic acid contents were found between 34.7% (Type 17) and 70.3% (Type 6). Saturated fatty acid contents of roasted melon seed oils ranged from 13.5% (Type 6) to 16.7% (Type 13). The major tocopherols in both roasted and unroasted melon seed oils were α-tocopherol, É£-tocopherol and δ-tocopherols. Melon seed oils are rich in linoleic, oleic acids and É£-tocopherol.

Effect of Frying on Physicochemical and Sensory Properties of Potato Chips Fried in Palm Oil Supplemented with Thyme and Rosemary Extracts.

Quality parameters of potato chips (flat and serrated) fried either in palm oil (PO) alone or containing natural (thyme (TPO) and rosemary (RPO) extracts) and synthetic BHT (BPO) antioxidants were evaluated during storage period. The free fatty acid and peroxide values of chips fried in PO (control) were found between 0.18 and 0.21% to 1.00 and 1.04 meqO2/kg during the first storage month, respectively. However, these values were 0.07-0.10% and 0.55-0.90 meqO2/kg for chips fried in TPO, respectively. The water contents increased when storage time increased from 1 to 7 month and their values changed between 0.49 and 1.95% (flat potato chips in BPO) and between 0.88 and 1.24% (serrated potato chips in TPO). The total trans-fat contents were 0.13% (serrated potato chips in BPO) and 0.35% (both flat and serrated potato chips in PO) at the start of storage. The total trans-fat content after 7 months were 0.13% (PO fried flat and serrated potato chips) and 0.17% (serrated potato chips fried in BPO, TPO and RPO). The acrylamide contents varied between 152 (serrated potato chips in PO) and 540 µg/kg (flat potato chips fried in RPO) at the beginning of storage. However, the acrylamide contents changed during 7th storage month and ranged from 182 (serrated potato chips in PO) to 518 µg/kg (flat potato chips in RPO). Among fatty acids, while palmitic acid are determined between 37.14 (flat chips in PO) and 41.60% (serrated chips in TPO), oleic acid varied between 30.0 (flat chips in RPO) and 33.00% (serrated chips in PO). Sensory evaluation showed that PO containing antioxidants showed better consumer preference for potato chips until the end of storage.

The influence of fermentation and bud sizes on antioxidant activity and bioactive compounds of three different size buds of Capparis ovata Desf. var. canescens plant.

The impact of fermentation and bud size on the antioxidant activity, total phenolic content (TPC), and bioactive compounds of caper buds were investigated. The results showed significant differences in the bioactive properties depending on bud sizes and fermentation process. Antioxidant activity values of fresh caper buds were ranged between 69.61% (bid size) and 72.78% (small size), whereas the values of fermented ones varied between 12.50% (big size) and 39.09% (small size). TPC of fresh caper buds were found in the range of 357.81 mg GAE/100 g (medium size) and 372.22 mg GAE/100 g (small size), while those of fermented buds were ranged from 167.53 mg GAE/100 g (medium) to 246.01 mg GAE/100 g (small). Apigenin-7-glucoside, (+)-catechin, 1,2-dihydroxybenzene, and 3,4-dihydroxybenzoic, syringic, and gallic acids were the major phenolic compounds in both fresh and fermented caper buds. Overall, this study clearly demonstrated that both fermentation process and bud size significantly affected the antioxidant activity, TPC, and phenolic compounds of caper buds.

Influence of Roasting on Oil Content, Bioactive Components of Different Walnut Kernel.

A study was carried out to evaluate oil contents, fatty acid composition and tocopherol contents of several walnut types in relation to roasting process. The major fatty acid identified was linoleic acid in both roasted and unroasted walnut oils. Linoleic acid contents of unroasted walnut oil varied from 46.44 (Type 9) and 63.59% (Type 7), while the linoleic acid contents of roasted walnut oils at 120℃/h ranged from 55.95% (Type 3) to 64.86% (Type 10). Interestingly, linolenic acid contents of both roasted and unroasted oils changed between 9.43 (Type 10) and 16.29% (Type 8) to 9.64 (Type 10) and 16.58% (Type 8), respectively and were significant (p < 0.05) different. γ-tocopherol content of unroasted walnut oils varied between 6.3 (Type 3) and 11.4 mg/100g (Type 1) and γ-tocopherol contents of roasted walnut oils ranged between 28.1 (Type 8) and 38.2 mg/100g (Type 3). The oil could be useful for industrial applications owing to good physicochemical properties. Fatty acid values for oil obtained from roasted walnut were slightly higher than those reported for unroasted walnut oils.

Influence of Sumac Extract on the Physico-chemical Properties and Oxidative Stability of Some Cold Pressed Citrus Seed Oils.

The acidity values changed between 1.03 mgKOH/100g (control) and 1.11 mgKOH/100g (0.1% extract) for orange oil, 1.06 mgKOH/100g (0.5% extract) and 1.13 mgKOH/100g (0.1% extract) and 1.25 mgKOH/100g (0.5% extract) and 1.31 mgKOH/100g (control) for mandarin oil. The peroxide values were determined between1.37 meqO2/kg (0.5% extract) and 1.43 meqO2/kg (0.1% extract) for orange oil, between 1.24 meqO2/kg (control) and 1.27 meqO2/kg (0.1% extract) for lemon and 1.60 meqO2/kg (0.5% extract) and 1.71 meqO2/kg (control) in mandarin oil samples. The viscosity values of samples changed between 0.051 Pa.S (control) and 0.065 Pa.S (0.5% extract) for orange, 0.051 Pa.S (control) and 0.067 Pa.S (0.5% extract) lemon and 0.044 Pa.S (control) and 0.057 Pa.S (0.5% extract) in mandarin oil samples. At the end of storage study (28th day), the acidity values significantly changed, and their values ranged between 2.28 mgKOH/100g (0.5% extract) and 3.64 mgKOH/100g (control) in orange, 1.67 mgKOH/100g (0.5% extract) and 2.28 mgKOH/100g (control) in lemon and 1.74 mgKOH/100g (0.5% extract) and 2.36 mgKOH/100g (control) in mandarin oil samples. While peroxide values vary between 11.68 meqO2/kg (0.5% extract) and 32.57 meqO2/kg (control) for orange, 12.55 meqO2/kg (0.5% extract) and 34.63 meqO2/kg (control) for lemon and between 17.56 meqO2/kg (0.5% extract) and 37.81 meqO2/kg (control) for mandarin oils, viscosity values after 28 day storage changed between 0.123 Pa.S (0.5% extract) and 0.675 Pa.S (control) in orange, 0.257 Pa.S (0.5% extract) and 0.697 Pa.S (control) in lemon and 0.215 Pa.S (0.5% extract) and 0.728 Pa.S (control) in mandarin oil samples.

The effect of harvest times on bioactive properties and fatty acid compositions of prickly pear (Opuntia ficus-barbarica A. Berger) fruits.

In the study, the impact of harvest time on total phenolic content, antioxidant activity, and phenolic compounds of prickly pear (Opuntia ficus-barbarica A. Berger) fruit pulp and the oil content and fatty acids profile of the seed were investigated. The highest total phenolic content was determined as 156.77 mg/100 g in July 1 harvest, while the maximum antioxidant activity and total oil content were found as 9.81% and 6.80% at the last stage of maturation (15 August), respectively. The highest oleic (28.51%), palmitic (22.61%) and stearic acid contents (9.20%) in seed oil were observed in June 15 harvest. The highest value for linoleic acid (57.50%) was detected in August 15 harvest. Prickly pear is a vital source of bioactive constituents such as phenolic and antioxidant substances in terms of being useful for human health and the optimum harvesting time to retain high quantities of most phenolic compounds is 1st July.

Effect of Varieties on Bioactive Properties and Mineral Contents of Some Sorghum, Millet and Lupin Seeds.

In this study, some physico-chemical properties, amino acids, fatty acids, sugars and mineral contents of sorghum, millet and lupin seeds. Sorghum (red, white and yellow) and millet seeds were purchased from market in Saudi Arabia (Riyadh). Lupin seeds were provided from in Turkey (Konya). Protein contents of seed samples ranged from 8.6% (yellow sorghum) to 37.7% (lutop) (p < 0.05). The extractable phenolics contents for gallic acid equivalent (GAE) of grains ranged between 1.43 mgGAE/g (white sorghum) to 8.23 mgGAE/g (red sorghum), and hydrolysable phenolics contents for GAE of grains varied between 1.48 mgGAE/g (white sorghum) to 26.10 mgGAE/g (red sorghum (p < 0.05). Total phenol contents of seeds were found between 2769 mg GAE/g (bablon) to 6087 mgGAE/g (yellow sorghum) (p < 0.05). Amino acid contents of millet changed between 0.02% (ornithine) and 2.07% (glutamic acid), while amino acid contents of yellow sorghum range from 0.02% (hydroxyproline) to 1.71% (glutamic acid), amino acid values of white sorghum changed between 0.02% (hydroxyproline) and 2.21% (glutamic acid), amino acid values of lutop seed changed between 0.02% (ornithine) and 6.77% (glutamic acid) (p < 0.05).While the oleic acid contents change between 25.27% (white sorghum) and 53.50% (Bablone), linoleic acid contents ranged from 14.60% (Bablone) to 42.67% (Millet) (p < 0.05). However, the amount of potassium in the seeds varied between 1831.34 mg/kg (while sorghum) and 11895.8 mg/kg (Lutop). Generally, protein, oleic acid, amino acid and mineral contents of lupin varieties were higher as compared to those of millet phenol, anthocyanin and sorghum seeds.

The Effect of Different Solvent Types and Extraction Methods on Oil Yields and Fatty Acid Composition of Safflower Seed.

The aim of this study was to determine the effect of different extraction solvents (petroleum benzene, hexane, diethyl ether and acetone) and extraction methods (hot and cold) on oil yield of safflower seeds and its fatty acid compositions. Oil contents of safflower seeds extracted by hot extraction system were changed between 37.40% (acetone) and 39.53% (petroleum benzene), while that of cold extraction was varied between 39.96% (petroleum benzene) and 39.40% (diethyl ether). Regarding the extraction solvents, the highest oil yield (39.53%) was obtained with petroleum benzene, while the minimum value (37.40%) was found with acetone under hot extraction condition. The main fatty acids observed in all extracted oil samples were linoleic, oleic and palmitic acids. Oleic acid contents of safflower oils extracted by hot extraction system was ranged between 41.20% (acetone) and 42.54% (hexane), its content in oils obtained by cold extraction method was varied between 40.58% (acetone) and 42.10% (hexane and diethyl ether). Linoleic content of safflower oil extracted by hot extraction system was found between 48.23% (acetone) and 49.62% (hexane), while that oil extracted by cold method range from 48.07 (hexane) to 49.09% (acetone). The fatty acid composition of safflower seeds oil showed significant (p < 0.05) differences depending on solvent type and extraction method. The results of this study provide relevant information that can be used to improve organic solvent extraction processes of vegetable oil.

The Effect of Olive Varieties on Fatty Acid Composition and Tocopherol Contents of Cold Pressed Virgin Olive Oils.

In this study, fatty acid composition and tocopherol contents of cold pressed olive oils belonged to Ayvalik, Gemlik, Domat, Çilli, Çöpasi and Söbüasi varieties were determined. The fatty acid composition of the olive oils showed differences depending on the olive variety. The major fatty acids such as oleic, linoleic and palmitic acids were found as 62.49-68.53%; 8.30-17.93%; 14.39-19.47%, respectively. The highest oleic, linoleic and palmitic acid contents were determined in the varieties of Çilli (68.53%), Söbüasi (17.93%) and Gemlik (19.47%), respectively. Palmitic, oleic and linoleic fatty acids of the local varieties such as Çilli, Çöpasi, Söbüasi were similar to those of Ayvalik and Gemlik varieties. The most abundant isomer of tocopherol in olive oils was α-tocopherol (18.22-36.02 mg/100g). The highest α- and γ- tocopherols were observed in olive oils of Söbüasi variety (36.02 mg/100g) and Gemlik variety (8.12 mg/100g), respectively. It is concluded that the olive variety is an important factor on the fatty acid composition and tocopherol content of the olive oil.

Influence of Storage and Roasting on the Quality Properties of Kernel and Oils of Raw and Roasted Peanuts.

The changes in chemical properties of the peanut varieties (NC-7 and ÇOM) in the raw and roasted forms stored at 30°C for 8 months were monitored. Acidity and peroxide values of raw and roasted NC-7 and ÇOM kernel oils increased during storage. The unsaturated fatty acids such as oleic, linoleic acids of roasted peanut oils gradually decreased during storage. While the oleic acid contents of raw NC-7 oil changed 46.14% (month 0) and 43.14% (month 8), the oleic acid contents of roasted NC-7 kernel oils varied between 42.38% (month 8) and 45.61% (month 0) during storage. In addition, while the oleic acid contents of raw ÇOM kernel oil decreased from 49.87% (month 0) to 46.09% (month 7), the oleic acid contents of roasted ÇOM kernel oil decreased from 48.88% (month 0) to 45.24% (month 8) during storage. The highest linoleic acid were found in the initial periods of storage for raw and roasted NC-7 and ÇOM oils. In addition, the α-tocopherol contents of both raw and roasted peanut kernel oils changed between 20.38 mg/100 g (0.month) and 17.58 mg/100 g (month 8) to 21.45 mg/100g (month 0) and 18.64 mg/100 g (month 8) during storage, respectively. Significant variations were observed in tocopherol contents of peanut varieties due to processing.

The effect of heat treatment on phenolic compounds and fatty acid composition of Brazilian nut and hazelnut.

Brazilian peanut oil content increased with oven heating (65.08%) and decreased with microwave heating process (61.00%). While the phenolic content of untreated Brazilian nut was the highest of 68.97 mg GAE/100 g. Hazelnut (Sivri) contained the highest antioxidant activity (86.52%, untreated). Results reflected significantly differences between the antioxidant effect and total phenol contents of Brazilian nut and hazelnut (Sivri) kernels heated in the oven and microwave. Microwave heating caused a decrease in antioxidant activity of hazelnut. Gallic acid, 3,4-dihydroxybenzoic acid and (+)- and catechin were the main phenolic compounds of raw Brazilian nut with the value of 5.33, 4.33 and 4.88 mg/100 g, respectively, while the dominant phenolics of raw hazelnut (Sivri) kernels were gallic acid (4.81 mg/100 g), 3,4-dihydroxybenzoic acid (4.61 mg/100 g), (+)-catechin (6.96 mg/100 g) and 1,2-dihydroxybenzene (4.14 mg/100 g). Both conventional and microwave heating caused minor reduction in phenolic compounds. The main fatty acids of Brazilian nut oil were linoleic (44.39-48.18%), oleic (27.74-31.74%), palmitic (13.09-13.70%) and stearic (8.20-8.91%) acids, while the dominant fatty acids of hazelnut (Sivri) oil were oleic acid (80.84%), respectively. The heating process caused noticeable change in fatty acid compositions of both nut oils.

Effect of the Harvest Time on Oil Yield, Fatty Acid, Tocopherol and Sterol Contents of Developing Almond and Walnut Kernels.

Oil content and bioactive properties of almond and walnut kernels were investigated in developing almond and walnut kernels at 10 days intervals. The oil contents of almond and walnuts after the first harvest (1.H) stage changed between 46.2% and 55.0% to 39.1% and 70.5%, respectively (p<0.05). Oleic acid contents of almond and walnut oils ranged from 71.98% (1.H) to 78.68% (5.H) and 10.51% (1.H) to 16.78% (2.H) depending on harvest (H) times, respectively (p<0.05). In addition, linolenic acid contents of walnut and almond oils were found between 62.35% and 67.78%, and 12.02% and 17.65%, respectively. The almond kernel oil after the first harvest stage contained 1.045, 1.058, 1.018, 0.995 and 0.819 mg/kg ɑ-tocopherol, respectively. γ-Tocopherol contents of walnut oil changed between 1.364 (3.H) and 2.954 mg/kg (1.H). The ß-sitosterol contents of both almond and walnut oils were found between 1956.6 (5.H) and 2557.7 (1.H), and 1192.1 (3.H) and 4426.4 mg/kg (1.H). The study exhibited the presence of high percentage of oleic and linoleic for almond and walnut, respectively, and γ-tocopherol and ß-sitosterol.

Pecan walnut (Carya illinoinensis (Wangenh.) K. Koch) oil quality and phenolic compounds as affected by microwave and conventional roasting.

In this study, the effects of conventional and microwave roasting on phenolic compounds, free acidity, peroxide value, fatty acid composition and tocopherol content of pecan walnut kernel and oil was investigated. The oil content of pecan kernels was 73.78% for microwave oven roasted at 720 W and 73.56% for conventional oven roasted at 110 °C. The highest free fatty acid content (0.50%) and the lowest peroxide value (2.48 meq O2/kg) were observed during microwave roasting at 720 W. The fatty acid profiles and tocopherol contents of pecan kernel oils did not show significant differences compared to raw samples. Roasting process in microwave oven at 720 W caused the reduction of some phenolic compounds, while the content of gallic acid exhibited a significant increase.

Effect of harvest time on physico-chemical properties and bioactive compounds of pulp and seeds of grape varieties.

In this study, physicochemical properties and bioactive compounds of three grape varieties (Cardinal, Müsküle and Razaki) harvested at the three different harvest times (on time, one and two weeks earlier) were investigated. The highest antioxidant activity, total phenolic and flavonoid contents were observed in Razaki pulp and these were 82.854%, 127.422 mg/100 g, 3.873 mg/g, respectively. The contents of bioactive compounds in grape seeds were found higher than those in pulps. Similarly, seed of Razaki had higher antioxidant activity (91.267%) and total phenolic content (477.500 mg/100 g) when compared to results of other varieties. The key phenolic compounds of all grape variety and seeds were gallic acid, 3,4-dihydroxybenzoic acid, (+)-catechin ve 1,2-dihydroxybenzene. The oil content of grape seeds ranged from 8.50% (Razaki harvested one week ago) to 19.024% (Müsküle harvested one week ago). The main fatty acids of grapeseed oils were linoleic, oleic and palmitic acids. In addition, the oil of Razaki seeds was rich in tocopherols when compared to the other varieties.

Oil content and fatty acid composition of eggs cooked in drying oven, microwave and pan.

In this study, the effect of heating on the oil yield and fatty acid composition of eggs cooked in drying oven, microwave oven, pan and boiled were determined, and compared. The highest oil content (15.22%) was observed for egg cooked in drying oven, while the lowest oil (5.195%) in egg cooked in pan. The cooking in microwave oven caused a decrease in oleic acid content (46.201%) and an increase in the amount of palmitic acid content (26.862%). In addition, the maximum oleic acid (65.837%) and minimum palmitic acid (14.015%) contents were observed in egg oil cooked in pan. Results showed that fatty acids were significantly affected by cooking method. This study confirms that the cooking processing influences the fatty acid composition of egg oils.

Identification of titanium dioxide nanoparticles in food products: induce intracellular oxidative stress mediated by TNF and CYP1A genes in human lung fibroblast cells.

Food grade TiO2 (E171) is a synthetic additive, and widely used as a coloring agent in many foods, pharmaceutical and personal care products. A few reports have highlighted that insoluble particulates (less than 200nm) of food grade TiO2 are found in many foods and confectionary products. However, information regarding the physico-chemical properties (i.e., size and shape)-based food grade TiO2 nanotoxicity related human health issues are limited. The main goal of this study is to examine the presence of nano-sized particulates and its structural characteristics of food grade- TiO2 materials and to assess the acute cellular uptake and metabolic stress induced by these particulates in human lung fibroblast (WI-38) cells. The results of transmission electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction studies indicated that about food grade TiO2 sample contains spherical shaped particulate forms in the nano-scale range, <100nm. The intracellular oxidative stress in human lung fibroblast cells (WI-38) was assessed through studies investigating the cellular uptake of the particles, changes in nuclear and cytoplasmic morphology, intracellular ROS, mitochondrial trans-membrane potential, the cell cycle and the expression of genes linked to metabolic stress markers. Altogether our data clearly indicate that primary metabolic stress indicators such as changes in the intracellular ROS, the dose-dependent loss of the mitochondrial membrane potential, alterations in cell cycle progression (G2/M>S>G0/G1) and changes in the TNF and CYP1A gene expression pattern are linked to cellular stress. Thus, food grade TiO2 as nano-scaled contaminants could not only be potential human health risk factors, suggesting that safety considerations with special respect to a few crucial factors such as size, and shape should be considered and regulated by food regulators.