الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
The world production of citrus is 122.09 million tons during 2008. Orange constitutes about 60% of the total citrus world production. In 2008, 3.23 million tons of citrus fruit was produced in Egypt contained 2.14 million tons of orange. A large portion of this production is addressed to the industrial extraction of citrus juice which leads to huge amounts of residues, including peel and segment membranes. Peels represent between 50 to 65%of total weight of the fruits and remain as the primary byproduct. If not processed further, it becomes waste produce odor, soil pollution, harborage for insects and can give rise to serious environmental pollution. Estimated waste resulting from the processing grapes 6-10% of raw materials. Grape by-products, for instance, constituted mainly by peels, contain a high amount of secondary metabolites including phenolic acids, flavanols and anthocyanin which are reported to possess antibacterial, antiviral, antioxidant, anti-inflammatory, anti-cancerogenic and prevent diseases. The obtained results are summarized as :
1 Two food plants wastes were assessed and studied for their approximate chemical analysis and results showed that pH of orange and grape peels extract were 5.25 , 4.51 respectively, while for ash and moisture were (3.5% , 66.5%), (7.88 % , 55 % ) respectively. Results also showed that grape peels consider as a good sources for potassium and Zinc,as it contained 469, 15 mg/100g dry weight respectively, which means that grape peels were more benefit in K and Zn contents than orange peels.
2 Total polyphenols and anthocyanins
Results showed that the amount of total poly phenolic was
6.6 mgGAEs.mg-1 more than the fresh peels being 4.32 mgGAEs.mg-1 , while the amount of anthocyanins was less 40 mg/L than the fresh peels being 0.118 g/g DW.
3 Antioxidant activity of polyphenols and anthocyanins from orange and grape peels .
A ) Scavenging effect on 1,1-Diphenyl-2-picrylhydrazyl (DPPH)
Results showed that the scavenging effect of orange and grape peel wastes were measured at 0.2 mg /ml concentration and gave low values 1.276 and 9.345 % respectively in comparison with the synthetic antioxidant BHT being 76.2 % at 0.2 mg /ml concentration and increased with increasing the concentration until 1mg/ml to 25.638 and 53.048 % in orange and grape peel respectively. It is extremely important to point out that strong correlation was observed between radical scavenging activity and polarity of samples. Extracts possesses the ability to reduce DPPH free radical and did so in a linear line.
B ) Reducing power
the most active sample of orange and grape peel wastes were measured being 1.025 , 0.297 at 2.5 mg/ml concentration respectively while it was higher for the synthetic antioxidant BHT being 3.491 indicating the strongest effect of orange peels at 2.5 mg /ml concentration.
4 Extraction methods for polyphenols and anthocyanins
Results showed that the amount of polyphenols compounds and anthocyanins extracted from orange and grape peels by three different methods ( Convential Extraction , Aqueous Extraction and Supercritical Fluid Extraction by CO2) . The yield of both polyphenols and anthocyanins extracted by convential extraction was higher being 27.1% and 32.52% respectively than aqueous extraction being 6.05% ,9.88%. While the yield of bioactive compounds extracted by SFE was lower (1.1% and 0.63%) than both previous methods with 96% purity but with high price cost due to the yield decrement.
5 Production of nano particles
Nano particles were achieved for both extracted polyphenols and anthocyanin with some modification by using homogenization at 15,500 rpm for 30 min and the morphology of extracted nano polyphenols compounds and nano anthocyanins were obtained by using Transmission Electrom Microscopy was 13.63 to 19.90 nm and 40 to 50nm for nano polyphenols compounds and nano anthocyanins respectively. These results indicate an approximate homogenized particles of the bioactive ingredients extracts.
6 Antioxidant activity of nano polyphenols and anthocyanins
A ) Scavenging effect on 1,1-Diphenyl-2-picrylhydrazyl (DPPH)
The scavenging effect of nano anthocyanins showed more strongest effect 55 % than nano polyphenolic compounds being 50.456 % at the concentration 40 µg /ml . Results showed that these extracts possess the ability to reduce DPPH free radical and did so in a linear line.
B ) Reducing power
The reducing power of the samples increased with increasing the concentration and the most active sample of nano polyphenols and nano anthocyanins was 1.995 , 2.805 at 40 µg /ml respectively.
7 Toxicity Test of nano compounds
Brine shrimp toxicity test showed that the nano polyphenols and anthocyanin with LC50 of 1.56 , 1.89 mg/ml were toxic while at 1.25 mg /ml both nano polyphenols and anthocyanin have no toxic symptoms mortality to the larvae shrimp.
8 Encapsulation of nano polyphenols and anthocyanin
Encapsulation processes for nano polyphenols and anthocyanin compounds were obtained by Ca-alginate of at 1.25 mg /ml concentration.
9 Application of nano anthocyanin in jelly
The T- test of strawberry jelly (A2) and jelly supplemented with nano anthocyanins (A3) indicated that there are non-Significant differences between them for color parameters were p- value> 0.05 and therefore nano anthocyanins extracted from grape peels as a natural source could be used as color agent in jelly rather than synthetic agents with more quantities and low costs in addition to health beneficial.
10 Application of nano polyphenols in Pineapple jelly.
10.1 Sensory characteristics
The jelly crystals were organoleptically tested by a semi-trained panel of five members. Pineapple jelly supplemented with nano polyphenols does not affect on the sensory characteristics because there are non-significant differences between the samples (A1, A2, A3 and A4). Therefore nano antioxidant (polyphenols) extracted from natural sources (orange peels) was cheaper and have biological benefits.
10.2 Scavenging effect (%) of Pineapple jelly supplemented with different concentration of nano polyphenols on DPPH free radical.
The scavenging effect for Pineapple jelly supplemented with different concentrations of nano polyphenols showed that the concentration of 1.25 mg/ml (A3) had highest value 78% followed by that of 0.625 mg/ml (A2) was 59.78%, then 0.3125 mg/ml (A1) was 27.54 %. Jelly Pineapple supported by nano polyphenols possesses the ability to reduce DPPH free radical and did so in a linear line.
11 Environmental Feasibility
Waste may be defined as any material or energy form that cannot be placed economically used, recovered or recycled at a given time and place. Nano sizing of food bioactive compounds from natural wastes using Top-down technique is a new technology in Egypt. The technology expenses per unit will be approximately from 400-500 L.E when the wastes could be recycled and there isn’t any product in Egyptian markets. So, the price will be probably well estimated when these products are in near future in all Egyptian markets ready for sale.