Plant phenolic extracts for the quality protection of frying oil during deep frying:Sources,effects,and mechanisms

Protection of frying oil from deterioration by adding plant phenolic extracts to guarantee the quality of fried foods becomes the primary approach to promote the sustainable development of deep frying.Therefore,sources,antioxidant effects,and mechanisms of plant phenolic extracts recently applied in the quality protection of frying oil as well as challenges for the actual use of these extracts are comprehensively reviewed in this study.Spices,herbs,berries,tea leaves,and fruit and vegetable wastes are common sources for preparing phenolic extracts showing comparative antioxidant capacity referring to the synthetic antioxidants.The general effect of using these natural antioxidants is the improvement of thermal stability to extend the shelf life of frying oil and thus the modification of edible quality of fried foods.Specifically,the increases in common quality attributes and amount of hazardous products and the oxidative reduction of unsaturated triacylglycerols without negatively influencing the sensory quality are inhibited when suitable plant extracts are applied.The incorporation of plant phenolic extracts other than synthetic counterparts in frying oil has been demonstrated as a potential method to improve the frying performance of oils.However,challenges for the scale application of plant phenolic extracts,such as the purity,thermal stability,and antioxidant timing,are still needed to be further investigated.

Fruit Yield and Quality, and Irrigation Water Use Efficiency of Summer Squash Drip-Irrigated with Different Irrigation Quantities in a Semi-Arid Agricultural Area

Fruit yield, yield components, fruit mineral content, total phenolic content, antioxidant activity and irrigation water use efifciency （IWUE） of summer squash responses to different irrigation quantities were evaluated with a ifeld study. Irrigations were done when the total evaporated water from a Class A pan was about 30 mm. Different irrigation quantities were adjusted using three different plant-pan coefifcients （Kcp, 100% （Kcp1）, 85% （Kcp2） and 70% （Kcp3））. Results indicated that lower irrigation quantities provided statistically lower yield and yield components. The highest seasonal fruit yield （80.0 t ha-1） was determined in the Kcp1 treatment, which applied the highest volume of irrigation water （452.9 mm）. The highest early fruit yield, average fruit weight and fruit diameter, length and number per plant were also determined in the Kcp1 treatment, with values of 7.25 t ha-1, 264.1 g, 5.49 cm, 19.95 cm and 10.92, respectively. Although the IWUE value was the highest in the Kcp1 treatment （176.6 kg ha-1 mm-1）, it was statistically similar to the value for Kcp3 treatment （157.1 kg ha-1 mm-1）. Total phenolic content and antioxidant activity of fruits was higher in the Kcp1 （44.27 μg gallic acid equivalents （GAE） mg-1 fresh sample） and in the Kcp2 （84.75%） treatments, respectively. Major （Na, N, P, K, Ca, Mg and S） and trace （Fe, Cu, Mn, Zn and B） mineral contents of squash fruits were the highest in the Kcp2 treatment, with the exception of P, Ca and Cu. Mineral contents and total phenolic content were signiifcantly affected by irrigation quantities, but antioxidant activity was not affected. It can be concluded that the Kcp1 treatment was the most suitable for achieving higher yield and IWUE. However, the Kcp2 treatment will be the most suitable due to the high fruit quality and relatively high yield in water shortage conditions.

Ultrasound-assisted intensified aqueous extraction of phenolics from waste Syzygium cumini leaves:Kinetic studies and evaluation of antioxidant,antidiabetic and anticancer potential

This is the first report illustrating the extraction of total phenolic compounds(TPC)using the ultrasound-assisted aqueous extraction(USAE)technique from waste Syzygium cumini leaves(WSCL).A kinetic study indicated that Peleg’s model was appropriately fitted to the experimental data when the effect of different parameters was checked on extraction with respect to time.Extraction yields of total phenolic contents(TPC)and total flavonoid contents(TFC)were 78.38 mg GAE/g,and 10.15 mg CE/g,respectively,at optimized parameters of 1:25 WSCL:water,35℃ temperature,134 W power,50%duty cycle and in 9 min of sonication time.Cumulative yields of TPC and TFC obtained by 5 sequential stirred batch extraction were 79.36 mg GAE/g and 10 mg CE/g,respectively.The cost and energy requirement of the USAE process was around 3000 times less than that of the Soxhlet technique.SEM images showed the changes in the morphology of the WSCL surface area before and after ultrasonic extraction.FTIR analysis showed the presence of O-H,N-H,C-H,C=C,and halogenated functional groups.The obtained WSCL extract showed antioxidant potential with an IC_(50) value of 15.64μg/mL.IC_(50) values of extract forα-amylase andα-glucosidase inhibitions were 8.3 and 6.64μg/mL.Antiproliferation activity against breast,cervical,and lung cancer showed the potential with GI50 values 252.8,112.5,and 97.8μg/mL,respectively.Aqueous extract of Syzygium cumini leaves can be used to treat oxidative stress,diabetes,and cancer.

In vitro antioxidant assessment and a rapid HPTLC bioautographic method for the detection of anticholinesterase inhibitory activity of Geophila repens

OBJECTIVE： Geophila repens （L.） I. M. Johnst. （Rubiaceae）, a small, creeping, perennial herb, is claimed to have memory-enhancing property. The goal of this study was to assess its antioxidant and anticholinesterase activity and conduct a rapid bioautographic enzyme assay for screening acetylcholinesterase （ACHE） and butyrylcholinesterase （BChE） inhibition of G. repens extracts. METHODS： Antioxidant activity of G. repens extracts was assessed by performing 1,1-diphenyl-2- picrylhydrazyl （DPPH）, nitric oxide （NO）, superoxide （SOD）, hydroxyl （OH） and total antioxidant capacity （TAC） assays. Anticholinesterase activity was investigated by quantifying the AChE and BChE inhibitory activities of chloroform （CGR）, ethyl acetate （EGR） and methanol （MGR） extract fractions from G. repens leaves. A rapid high-performance thin-layer chromatography （HPTLC） bioautographic method for the detection of AChE and BChE inhibition was performed. RESULTS： Among all extract fractions, EGR exhibited the highest half maximal inhibitory concentration （IC50） in DPPH, SOD, NO, OH and TAC assays, with IC50 of （38.33 ± 3.21）, （45.14 ±1.78）, （59.81± 1.32）, （39.45 ± 0.79） and （43.76 ± 0.81 ） μg/mL respectively. EGR displayed competitive, reversible inhibition of AChE and BChE activities with IC50 of （68.63±0.45） and （59.45 ±0.45）μg/mL, respectively. Total phenolic and flavonoids contents of EGR were found to be 360.42 mg gallic acid equivalents and 257.31 mg quercetin equivalents per gram of extract. Phytoconstituents of the EGR extract that were inhibitors of cholinesterase produced white spots on the yellow background of HPTLC plates in the bioautographic test. CONCLUSION： The results of this study revealed that phenols and flavonoids could be responsible for the antioxidant, anticholinesterase activities of G. repens.

Impact of simulated in vitro gastrointestinal digestion on bioactive compounds,bioactivity and cytotoxicity of melon (Cucumis melo L. inodorus) peel juice powder

The objectives of this research work were to evaluate the effect of in vitro gastrointestinal digestion (GIT) on melon peel juice (MPJ) powder from fruit processing industry by-products,considering (i) the recovery and accessibility indexes,(ii) the changes on antioxidant activity,and (iii) the prebiotic effect.Throughout exposition to GIT conditions a decrease on the total phenolic content (TPC = 65.31%) and antioxidant activity by ABTS = 39.77% and DPPH = 45.91% were observed.However,these both parameters exhibited stable accessibility,accounting with 81.89%,76.55%,and 54.07% for TPC,ABTS and DPPH,respectively.After gastrointestinal digestion,the non-absorbed fraction exhibited a positive impact on the growth of Bifidobacterium and Lactobacillus strains,possibly associated with the high content of simple sugar (glucose and fructose).This fraction also showed to be safe on Caco-2 intestinal cells.These findings suggest that MPJ might be used as a potential food functional ingredient.

Ethanolic extract of rice bran: a thermally stable preservative for edible oils and cake

The purpose of this study was to evaluate the thermal stability of the rice bran extract (RBE) and analyze the effect of RBE on the shelf-life of sunflower oil and the quality characteristics and shelf-life of baked cake. The thermal stability of RBE was evaluated by a Rancimat test using sunflower oil. Properties such as moisture content, porosity, crumb density and pore area of cakes baked with RBE and the synthetic antioxidant butylated hydroxytoluene (BHT) were compared. Sensory properties such as taste, aroma, texture, color and overall acceptability of the cake samples were compared using a sensory panel test. The shelf-life of the cakes was evaluated by microbial counts and chemical methods. Thermally treated RBE and BHT for 2 h at 180 °C retained 75% of their initial capacity in protecting sunflower oil while RBE had a significantly higher protection factor (p < 0.05). Cakes baked with RBE received higher scores for taste, color and overall acceptability compared to control or BHT-added cake. BHT-added cake and RBE-added cake exceeded the aerobic plate count (APC) and yeast and mold count (YMC) on days 11 and 13 respectively, while the control cakes without added antioxidants exceeded the APC and YMC on day 7. Both BHT- and RBE-added cakes maintained hexanal levels below 5 mg/kg over 28 days while the control cake exceeded this level on day 21. The results suggest that RBE can be used as a natural food additive to improve the quality and shelf-life of baked foods and edible oils.