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Purpose: This study aimed to investigate the rapid restoration of indigenous hydrocarbon degraders after chemical oxidation, in order to enhance the subsequent biodegradation of crude oil in soils. Materials and methods: The Fe-SOM (2231 mg kg−1) and H2O2 were added into the oil-contaminated soil (total petroleum hydrocarbon (TPH): 16064 mg kg−1) for chemical oxidation. Then, the all and partial alkane re-biodegradation reagents were added for re-biodegradation experiments. Calculated and analyzed C-source (DOC and TPH) and N-source ( NH 4 + − N , NO 3 − − N , NO 2 − − N ) consumption and the population of hydrocarbon degraders in each period. Results and discussion: After chemical oxidation, the total biodegradation of all alkanes (re-biodegradation degree: 100%) with reagent for all alkane re-biodegradation in the late stage was higher than that in the early stage. Further study found that DOC was the main C-source and NH 4 + − N was the main N-source in the early stage, while TPH and nitrate were the main C&N-sources in the late stage of re-biodegradation. In other words, the C&N-sources changed over to TPH and nitrate in the late stage. After re-biodegradation stage, increasing biodegradation (from 644 mg kg−1 in the 1st stage to 842 mg kg−1 in the 3rd stage) was observed. Conclusions: The results showed that re-biodegradation of all alkanes could recover growth of indigenous hydrocarbon degraders and continuously increase biodegradation of all alkanes after chemical oxidation. The C&N-sources changed from DOC and NH 4 + − N to all alkanes and NO 3 − − N during re-biodegradation stage was the key factor. [ABSTRACT FROM AUTHOR]

The use of Advance Oxidation Process (AOPs) has been extensively examined in order to eradicate organic pollutants. This review assesses the efficacy of photolysis, O 3 based (O 3 /UV, O 3 /H 2 O 2 , O 3 /H 2 O 2 /UV, H 2 O 2 /UV, Fenton, Fenton-like, hetero-system) and sonochemical and electro-oxidative AOPs in this regard. The main purpose of this review and some suggestions for the advancement of AOPs is to facilitate the elimination of toxic organic pollutants. Initially proposed for the purification of drinking water in 1980, AOPs have since been employed for various wastewater treatments. AOPs technologies are essentially a process intensification through the use of hybrid methods for wastewater treatment, which generate large amounts of hydroxyl (•OH) and sulfate (SO4·−) radicals, the ultimate oxidants for the remediation of organic pollutants. This review covers the use of AOPs and ozone or UV treatment in combination to create a powerful method of wastewater treatment. This novel approach has been demonstrated to be highly effective, with the acceleration of the oxidation process through Fenton reaction and photocatalytic oxidation technologies. It is clear that Advance Oxidation Process are a helpful for the degradation of organic toxic compounds. Additionally, other processes such as •OH and SO4·− radical-based oxidation may also arise during AOPs treatment and contribute to the reduction of target organic pollutants. This review summarizes the current development of AOPs treatment of wastewater organic pollutants. • Advance oxidation process- Fenton and Fenton Type reaction. • Electrochemical advance oxidation process. • Removal of organic pollutants through advance oxidation. • Photo-Fenton types of reaction through Chloride ion. • Pesticides degradation by nano-zero valent materials. [ABSTRACT FROM AUTHOR]

Background: Chicken meat contains higher percentage of polyunsaturated fatty acids that are susceptible to oxidative deterioration ultimately leading towards lower consumer acceptability for chicken meat products. Accordingly, meat processing industries are looking for combinations of natural antioxidants to enhance the oxidative stability and consumer acceptability of meat based products. The present study aimed to investigate the influence of directly added quercetin dihydrate in combination with α-tocopherol on oxidative stability, color characteristics, total carbonyls and flavor volatile compounds in chicken meat patties. Methods: Considering the preliminary studies, 3 levels of quercetin dihdrate @ 25, 50 and 100 mg/kg meat in combination with α-tocopherol at the rate 100 and 200 mg/kg meat were added to develop chicken meat patties and were stored at refrigeration temperature for 7 days. The oxidative stability of the antioxidant treated patties was determined by measuring malonaldehydes using TBARS and total carbonyls assay. The color (Lightness, redness and yellowness) of the patties was determined by using Konica Minolta Color Meter. Moreover, the volatile compounds were measured through gas chromatography at various storage intervals. Results: The results elucidated that quercetin dehydrate inclusion at the rate of 50 mg/kg meat as well as particularly 100 mg/kg meat decreased the oxidation by reducing generation of malonaldehydes and total carbonyls in treated patties. Highest value for TBARS at initiation of storage was reported in (T0) as 1.93 ± 0.02 whereas lowest were reported in T6 and T5 as 0.37 ± 0.01 and 0.38 ± 0.03 that were increased to 3.47 ± 0.14, 0.90 ± 0.05 and 0.94 ± 0.34 at the completion of storage. Moreover, the lowest carbonyls also reported in T6 and the values at various storage intervals (1st, 3rd and 7th) were as 0.59 ± 0.025, 0.77 ± 0.015 and 1.02 ± 0.031, respectively. The antioxidants inclusion also inhibited volatile flavoring compounds particularly aldehydes like hexanal and pentanal in a dose dependent manner (p ≤ 0.05). Lowest hexanal values reported in T6 as 2488 ± 103 followed by T4 (3701 ± 111) at the start of the trial whereas highest in T0 (control) as 54,768 ± 431 that were increased to 9569 ± 607, 112,550 ± 897 and 359,826 ± 1285, correspondingly. The hexanal, as a critical indicator for the determination of volatiles in meat based products, was decreased with the addition of antioxidants and its highest values were reported in control group. Conclusions: Quercetin dihydrate addition along with alpha tocopherol is a pragmatic choice to improve oxidative storability and volatile flavor compounds in cooked meat patties. The data obtained will help meat processor to better develop antioxidant enriched formulations to augment oxidative stability and quality of processed meat products. [ABSTRACT FROM AUTHOR]

Background: Chia (Salvia hispanica L.) seeds have been described as a good source of lipids, protein, dietary fiber, polyphenolic compounds and omega-3 polyunsaturated fatty acids. The consumption of chia seed oil helps to improve biological markers related to metabolic syndrome diseases. The oil yield and fatty acids composition of chia oil is affected by several factors such as pre-treatment method and size reduction practices. Therefore, the main mandate of present investigate was to study the effect of different seed pre-treatments on yield, fatty acids composition and sensory acceptability of chia oil at different storage intervals and conditions. Methods: Raw chia seeds were characterized for proximate composition. Raw chia seeds after milling were passed through sieves to obtain different particle size fractions (coarse, seed particle size ≥ 10 mm; medium, seed particle size ≥ 5 mm; fine, seed particle size ≤ 5 mm). Heat pre-treatment of chia seeds included the water boiling (100 C°, 5 min), microwave roasting (900 W, 2450 MHz, 2.5 min), oven drying (105 ± 5 °C, 1 h) and autoclaving (121 °C, 15 lbs, 15 min) process. Extracted oil from pre-treated chia seeds were stored in Tin cans at 25 ± 2 °C and 4 ± 1 °C for 60–days and examined for physical (color, melting point, refractive index), oxidative (iodine value, peroxide value, free fatty acids), fatty acids (palmitic, stearic, oleic, linoleic, α-linolenic) composition and sensory (appearance, flavor, overall acceptability) parameters, respectively. Results: The proximal composition of chia seeds consisted of 6.16 ± 0.24 % moisture, 34.84 ± 0.62 % oil, 18.21 ± 0.45 % protein, 4.16 ± 0.37 % ash, 23.12 ± 0.29 % fiber, and 14.18 ± 0.23 % nitrogen contents. The oil yield as a result of seed pre-treatments was found in the range of 3.43 ± 0.22 % (water boiled samples) to 32.18 ± 0.34 % (autoclaved samples). The oil samples at day 0 indicated the maximum color (R and Y Lovibond scale) value for oven drying while at storage day 60 (25 ± 2 °C), the highest color value was found for autoclave pre-treatment. The slightly increasing trend of color values for all treatments was observed during the storage period. The lowest iodine value (182.83 ± 1.18 g/100 g at storage day 0 & 173.49 ± 1.21 g/100 g at storage day 60, 25 ± 2 °C) was calculated for autoclaved samples while the maximum iodine value (193.42 ± 1.14 g/100 g at storage day 0 & 190.36 ± 1.17 g/100 g at storage day 60, 25 ± 2 °C) was recorded for raw chia samples. The significant increasing trend for all treatments was observed in case of peroxide value and free fatty acids production during storage. Maximum decrease in linoleic (35 %) and α-linolenic (18 %) fatty acids was observed in autoclaved samples. The oil from pre-treated seed samples obtained decreasing scores for sensory parameters throughout the storage period at different conditions. Conclusions: As a result, chia seeds are an important source of lipids and essential fatty acids. The water boiling and high temperature processing of chia seeds provides instability to lipids during storage at room temperature. However, detailed investigation is required on the processing performance and storage stability of food products supplemented with pre-treated chia seeds and furthers their effect on biological system. [ABSTRACT FROM AUTHOR]

Whey butter is characterized with higher concentration of unsaturated fatty acids; the autoxidation of unsaturated fatty acids limits the shelf life of whey butter. We investigated the effect of almond peel extract on oxidative stabilization of whey butter at refrigeration temperature as the butter is put at refrigeration temperature in supermarkets for sale. Whey butter was added with 100 (T1), 200 (T2), 300 (T3) and 400 (T4) ppm concentrations of ethanolic almond peel extract, compared with a control, stored at refrigeration temperature (6 ± 1C). Changes in chemical characteristics were studied at the interval of 45 days. Supplementation of whey butter with almond peel extract did not show any effect on compositional attributes, rather it strongly inhibited the peroxidation of unsaturated fatty acids (P < 0.05). The iodine value of whey butter was greater than normal butter with no difference in refractive index and unsaponifiable matter. The peroxide value of 90-day stored whey butter added with 400 ppm almond peel extract and control was 0.62 and 1.59 (meqO2/kg). Supplementation of whey butter with almond peel extract markedly improved the induction period. Sensory characteristics of supplemented whey butter were not different from the normal butter (P > 0.05). Almond peel extract can be used for the long-term preservation of whey butter at refrigeration temperature. [ABSTRACT FROM AUTHOR]

Laccase is an enzyme that has potential ability of oxidation. It belongs to those enzymes, which have innate properties of reactive radical production, and its utilization in many fields has been ignored because of its unavailability in the commercial field. There are diverse sources of laccase producing organisms like bacteria, fungi and plants. Textile, pulp and paper industries discharge a huge quantity of waste in the environment, and the disposal of this waste is a big problem. To solve this problem, work has done to discover such an enzyme, which can detoxify these wastes and is not harmful to the environment. Laccases use oxygen and produce water as by product. They can degrade a range of compounds including phenolic and non-phenolic compounds. They also have ability to detoxify a range of environmental pollutants. Their property to act on a range of substrates and also to detoxify a range of pollutants have made them to be usable for several purposes in many industries including paper, pulp, textile and petrochemical industries. [ABSTRACT FROM AUTHOR]

Background: Milk fat is one of the complex fat and most sensitive biochemical compounds towards auto-oxidation. To enhance the shelf life, milk is subjected to Ultra-high Temperature (UHT) treatment followed by aseptic packaging. During the storage, several chemical and biochemical changes take place in lipid fraction of UHT milk. In current investigation, the effect of UHT treatment and storage was determined by making a comparison in fatty acid profile, triglyceride composition, organic acids and lipid oxidation of the thermally treated and stored milk with raw milk, which was not reported in earlier investigations. Methods: Raw milk samples were collected from the bulk storage facility of a dairy industry. The same milk was routed to UHT treatment and aseptically packaged samples were collected. The fatty acid profile, triglyceride composition, organic acids and lipid oxidation was determined in raw and UHT treated milk at 0, 30, 60 and 90 days. Fatty acid and triglyceride profile was determined on GC-MS while organic acids were determined by HPLC. For the measurement of induction period, professional Rancimat was used. Lipid oxidation was characterized through free fatty acids, peroxide value, anisidine value and conjugated dienes. Results: Compositional attributes of milk remain unchanged during the entire length of storage. Concentrations of short-chain fatty acids in raw and UHT milk were 10.49% and 9.62%. UHT treatment resulted in 8.3% loss of short-chain fatty acids. Up to 30 days, storage did not have any significant effect on fatty acid profile of UHT milk. Concentration of medium-chain fatty acids in raw and UHT treated milk was 54.98% and 51.87%. After 30, 60 and 90 days of storage, concentration of medium chain fatty acids was found 51.23%, 47.23% and 42.82%, respectively. Concentration of C18:1 and C18:2 in raw and UHT milk was 26.86% and 25.43%, respectively. The loss of C18:1 and C18:2 in UHT treatment was 5.32%. After 30, 60 and 90 days of storage, the concentrations of C18:1 and C18:2 were 24.6%, 21.06% and 18.66%, respectively. Storage period of 30 days was found non-significant, while noticeable variations were found in triglyceride profile of 60 and 90 days old samples of UHT milk. UHT treatment and storage period significantly affected the concentration of organic acids in milk. After UHT treatment, concentration of lactic acid, acetic acid, citric acid, pyruvic acid, formic acid, succinic acid and oxalic acid increased by 3.45, 0.66, 3.57, 0.68, 2.24, 2.16 and 1.63 mg/100 g. Effect of storage period on the production of organic acids in UHT milk was non-significant up to 30 days. After 60 days of storage period, the increase in concentration of lactic acid, acetic acid, citric acid, pyruvic acid, formic acid, succinic acid and oxalic acid was 3.79, 0.75, 4.69, 0.78, 2.83, 3.03 and 2.38 mg/100 g. After 90 days of storage period, the increase in concentration of lactic acid, acetic acid, citric acid, pyruvic acid, formic acid, succinic acid and oxalic acid was 7.3, 2.18, 9.96, 3.58, 11.37, 5.22 and 5.96%. Free fatty acids content of raw, UHT treated and 90 days old milk were 0.08%, 0.11% and 0.19%. UHT treated version of milk showed similar peroxide value. While, the storage remarkably affected the peroxide value. After 30, 60 and 90 days, peroxide value was 0.42, 0.62 and 1.18 (MeqO2/kg). Induction period of raw, UHT and stored milk was strongly correlated with peroxide value and fatty acid profile. Mean value of lipase activity in raw milk was 0.73 ± 0.06 μmoles/ml. UHT treatment significantly decreased the lipase activity. The lipase activity of milk immediately after the UHT treatment was 0.18 ± 0.02 μmoles/ml. Lipase activity of UHT milk after 30, 60 and 90 days of room temperature storage was 0.44 ± 0.03, 0.95 ± 0.07 and 1.14 ± 0.09 μmoles/ml. Color, flavor and smell score decreased through the storage of UHT milk for 90 days. Conclusion: The results of this investigation revealed that fatty acid and triglyceride profile changed after 60 and 90 days of storage. Production of organic acids led to the drop of pH and sensory characteristics in UHT milk during the long-term storage. Induction period can be successfully used for the determination of anticipatory shelf life of UHT milk. [ABSTRACT FROM AUTHOR]

Abstract: Intrinsically conducting PPy/ZnO composites were synthesized with varying amounts of zinc oxide (0–20wt.%) via a facile chemical oxidation polymerization approach. These composites were characterized for their structure, thermal stability, surface morphology and DC electrical conductivity by XRD, FT-IR, TGA, DSC, SEM and four-probe method respectively. FT-IR results show broadening and shifts of peaks towards lower wave numbers in all composites suggesting better conjugation and some chemical interactions between PPy and ZnO particles. Powder X-ray diffraction analysis demonstrated the amorphous nature of PPy and its composites as well with no indication of crystalline peaks. The percolation threshold for conductivity of PPy/ZnO composites was 15wt.% of the volume fraction of PPy. SEM and TGA data suggest that PPy/ZnO composites have high thermal stability due to better conformation, compactness and reduction of grain boundary volume with zinc oxide particle loading that in parallel enhanced their DC conductivity. [Copyright &y& Elsevier]

Ciprofloxacin (CIP) is a widespread emerging water pollutant and thus its removal from aquatic environment is vital. The use of Fe3+/H2O2 and Fe2+/H2O2 resulted in 38 and 64% removal of CIP (8.0 ppm), respectively, within 80 min reaction time (pH 5.8, [H2O2]0 = 80 ppm, and [iron]0 = 20 ppm). Low pH, high temperature, high dose of H2O2 and Fe2+, and low CIP concentration facilitated removal of CIP. The radical scavenger studies proved in situ generated OH to be involved primarily in the removal of CIP. The effect of temperature was used to estimate enthalpy and activation energies of the removal of CIP. At 800 min reaction time, the Fe2+/H2O2 resulted in 54% mineralization of CIP using 16.0 ppm [CIP]0, 320.0 ppm [H2O2]0, and 40.0 ppm [Fe2+]0. The potential degradation pathways of CIP established from the degradation of CIP by OH and products evolved was found to be initiated at C6 through the loss of fluoride ion. The acute and chronic toxicities of CIP and its degradation products were estimated with the final product found to be non-toxic. The results suggest that Fe2+/H2O2-mediated AOPs have high potential for degradation as well as toxicity elimination of CIP and its degradation products. [ABSTRACT FROM AUTHOR]