Effects of Freeze-dried Mulberry on Antioxidant Activities and Fermented Characteristics of Yogurt during Refrigerated Storage

The phenolic content and antioxidant potential of malting barley are important in brewing. The objective of our study was to investigate the effects of barley genotype, growing environment, and malting conditions on the total phenolic content and antioxidant activities of malting barley grown in North America. Eight barley cultivars grown at three locations over three years were used. For the malting study, a single barley cultivar, separated into different kernel size fractions, was germinated for various periods of time and then processed by kilning or freeze-drying. Total phenolic content (TPC) and some of the antioxidant activities, including DPPH, ABTS, and superoxide anion radical scavenging activities, reducing power, and iron (II) chelating activity, were significantly impacted by the barley genotype, growth environment, and their interactions. The TPC and most antioxidant activities were also influenced by malting conditions and were generally higher in the malted barleys of the thin kernel size fraction, four-day germination, and in samples processed by kilning, when compared to the plumper kernel size fractions, one and two days of germination, and freeze-dried samples, respectively. There were interactions between malting parameters, and stepwise regression analysis was used to suggest the contribution of each parameter to the TPC and antioxidant activities.

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Effect of Drying on the Bioactive Compounds and Antioxidant Activity of Rubus lambertianus

International Journal of Food Engineering ◽

10.1515/ijfe-2016-0412 ◽

2018 ◽

Vol 14 (2) ◽

Author(s):

Jun Yu ◽

Zijian Shangguan ◽

Xingju Yang ◽

Dan Sun ◽

Baoqing Zhu ◽

...

Keyword(s):

Bioactive Compounds ◽

Freeze Drying ◽

Antioxidant Activities ◽

Drying Methods ◽

Protective Effects ◽

Red Raspberry ◽

Hot Air Drying ◽

Hot Air ◽

Freeze Dried ◽

Total Anthocyanins

AbstractDifferent drying methods, including hot air drying (HAD), freeze drying (FD), spray drying and vacuum drying (VD), were investigated to determine their influence on the chromatic coordinates, phenolics, anthocyanins and antioxidant activities of dried red raspberry (Rubus lambertianus). Pelargonidin-3-O-glucoside and catechin were found to be the main anthocyanin and non-anthocyanin phenolics, respectively, in fresh red raspberry. The most effective method for controlling browning was FD. The highest protective effects against bioactive compounds were observed in freeze-dried powders, when measuring the total anthocyanins, the scavenging of DPPH (1,1-diphenyl-2-picrylhydrazyl) and hydroxyl radicals and the inhibition effects on lard oxidation. HAD was effective for the preservation of total phenolics, while VD was useful for protecting catechin and procyanidin B1.

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Alkaline-based curcumin extraction from selected zingiberaceae for antimicrobial and antioxidant activities

Pigment & Resin Technology ◽

10.1108/prt-08-2018-0071 ◽

2019 ◽

Vol 48 (4) ◽

pp. 293-300 ◽

Cited By ~ 1

Author(s):

Rashidi Othman ◽

Mohd Akram Abdurasid ◽

Noraini Mahmad ◽

Nurrulhidayah Ahmad Fadzillah

Keyword(s):

Ethyl Acetate ◽

Extraction Method ◽

Antioxidant Activities ◽

Inhibition Zone ◽

Single Peak ◽

Diffusion Method ◽

Powdered Sample ◽

Acetate Solution ◽

Content Type ◽

Freeze Dried

Purpose The purpose of this paper is to extract, characterise and quantify curcumin from selected Zingiberaceae of “kunyit” or turmeric (Curcuma longa), “temu lawak” or Javanese turmeric (Curcuma xanthorrhiza), “temu pauh” (Curcuma mangga), “lempoyang” (Zingiber zerumbet) and “bonglai” (Zingiber cassumunar) using alkaline and chemical-based extraction method for antimicrobial and antioxidant activities. Design/methodology/approach Through the alkaline-based extraction method, all parts of rhizome samples were freeze-dried for 72 h before grounded into a fine powder and kept at −20°C. The powdered sample (0.1 g) was weighed and placed in a 50 mL tube. About 20 mL of 2 M NaOH solution was added into the tube. The solution was allowed to stand for 30 min. Then, 20 mL of ethyl acetate was added into the tube. The solution was mixed well then centrifuged at 13,500 rpm for 3 min. The upper layer was collected using a pipette. The process was repeated until the upper layer became almost colourless. The collected ethyl acetate solution was concentrated using a rotary evaporator to remove the ethyl acetate from the extracted compound. The concentrated curcumin was placed in a universal bottle, which was then dried from the remaining ethyl acetate using nitrogen drying process. The dried curcumin was then stored inside the freezer at −20ºC. The antimicrobial activities were using agar diffusion method against bacterial and fungi, while the antioxidant activity was evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging assay. Findings All the samples successfully showed a single peak (curcumin) that gained from the high-performance liquid chromatography (HPLC) chromatogram analysis (at 425 nm) using the alkaline-based extraction method and the highest curcumin content was in turmeric (12.95 ± 1.07mg/g DW). At 10.0 mg/mL curcumin concentration, the best antibacterial activity was against on methicillin-resistant staphylococcus aureus (MRSA) with 7.50 ± 0.71 mm inhibition zone, while the best antifungal activity was against on Aspergillus niger with 8.00 ± 0.41 mm inhibition zone. The DPPH antioxidant test resulted in the highest inhibition (110.41 per cent) was at 0.25 mg/mL curcumin concentration. Originality/value Through HPLC analysis, all samples successfully showed a single peak of curcumin at 425 nm. The total carotenoid determination from turmeric revealed that the samples content was substantially higher using alkaline-based extraction (18.40 ± 0.07 mg/g DW) compared to chemical-based extraction (9.42 ± 0.20 mg/g ± SD).

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Different Extraction Solvents and Sample Preparation Methods Affect the Antioxidant Activities and Total Phenol Contents of Theobroma Cacao Powder (P01-016-19)

Current Developments in Nutrition ◽

10.1093/cdn/nzz028.p01-016-19 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

Author(s):

Hyoeun Yoo ◽

Hyun-Sook Kim

Keyword(s):

Antioxidant Activities ◽

Radical Scavenging Activity ◽

Radical Scavenging ◽

Methanol Solution ◽

Total Phenol ◽

Scavenging Activity ◽

Dpph Radical ◽

Dpph Radical Scavenging Activity ◽

Freeze Dried ◽

Dpph Radical Scavenging

Abstract Objectives Cacao(Theobroma cacao) has been widely consumed since more than 4000 years ago which was regarded as sacred food. Cacao has been considered as a strong antioxidant due to its abundant phenolic and especially flavonoid contents. In this experiment, different extraction solvents and methods were used to analyze whether these factors affect the antioxidant activities and phytochemical compounds of cacao powder extracts. Methods Four different cacao extract samples were examined to identify their anti-oxidative activities; raw cacao powder extracted in 70% methanol solution(RM), raw cacao powder extracted in 80% ethanol solution(RE), freeze dried cacao powder extracted in 70% methanol solution(FM), freeze dried cacao powder extracted in 80% ethanol solution(FE). Total phenolic compound content was calculated based on gallic acid standard curve and total flavonoid content was calculated based on the standard curve of quercetin. ABTS scavenging activity was experimented with ABTS reagent diluted by PBS(pH7.4) to make the O.D. value 0.7 ± 0.02 at 734 nm before using 2.5 mM ABTS. The DPPH radical scavenging activity was assessed by 1 mM DPPH methanol solution. Results The contents of total phenol compounds were 45.4 mg GAE/g(RM), 37.3 mg GAE/g(RE), 50.6 mg GAE/g(FM), and 52.7 mg GAE/g(FE). The contents of total flavonoid compounds were 34.3 mg QE/g(RM), 29.7 mg QE/g(RE), 85.1 mg QE/g(FM), and 89.7 mg QE/g(FE). FM group showed the highest ABTS radical scavenging activity which is a marker of antioxidant activity but the other sample groups represented almost as high ABTS radical scavenging activity as FM group. RM group showed the highest DPPH radical scavenging activity which is also a marker of antioxidant activity. Conclusions The results show that different extract solvents and sample preparation methods affect DPPH radical scavenging activity, total phenol and flavonoid contents of cacao powder extracts. Therefore, appropriate methods should be applied according to the purpose of the study. Funding Sources Department of Food and Nutrition, Sookmyung Women's University, Republic of Korea.

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Investigation of the antioxidant capacity of the components of Astragalus after membrane separation

E3S Web of Conferences ◽

10.1051/e3sconf/202018504061 ◽

2020 ◽

Vol 185 ◽

pp. 04061

Author(s):

Yandong Wang ◽

Yafei Guo ◽

Yingli Wang ◽

Zemin Zhang

Keyword(s):

Free Radicals ◽

Antioxidant Capacity ◽

Membrane Separation ◽

Antioxidant Activities ◽

Dose Effect ◽

Total Flavonoids ◽

Astragaloside Iv ◽

Separation Technology ◽

Freeze Dried ◽

Hydroxyl Free Radicals

Astragalus is commonly used in health supplements, and its flavonoids and saponins are the important material basis for immune system enhancement. The study on the effective component contents and antioxidant capacities of astragalus extract after membrane separation lays the foundation of the application of membrane separation technology in health supplement development. The astragalus extract was filtered by suction and passed through membranes of 10000 Da, 2500 Da, and 600 Da to obtain retentate 1 (M1), retentate 2 (M2), retentate 3 (M3) and permeate MT. UV/vis spectrophotometer was used to compare the contents of total flavonoids and total saponins before and after each step of membrane separation. High performance liquid chromatography (HPLC) was used to analyze the contents of Verbasil Glucoside and Astragaloside IV of all membrane separation samples, and the antioxidant activities were determined. The contents of flavonoids in membrane separation samples were significantly different. In the freeze-dried powders obtained from the membrane separation, the contents of total flavonoids and Verbasil Glucoside were the lowest in MT, M1 was the highest, and M3 was the second highest. The order of contents of total saponins and Astragaloside IV of the freeze-dried powders from membrane separation was as follows: M3 > M1 > M2 > MT. Among them, the content of total saponins in the freeze-dried powder of M3 was the highest, which reached 2.67 times of that of the astragalus extract. The order of the scavenging activities of membrane separation samples for DPPH free radical was: MT > M3 > M2 > M1 > astragalus extract. The strongest scavenging activity of hydroxyl free radicals was found in M3, and the scavenging rates of hydroxyl free radicals in all samples were higher than those of VC. The total antioxidant capacity of FRAP showed a certain dose-effect relationship. At the same concentration, the FRAP values of M1 and MT were higher than other samples. Membrane separation technology can be used to separate and purify the effective components from astragalus extract. M3 has the highest contents of the total flavonoids and total saponins, and its antioxidant capacity is better than that of astragalus extract and other samples obtained by membrane separation.

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Antimicrobial and Antioxidant Activities of Deer Blood Hydrolysate on Fresh Beef during Refrigerated Storage

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.634-638.1417 ◽

2013 ◽

Vol 634-638 ◽

pp. 1417-1422

Author(s):

Shuai Wang ◽

Feng Bo Xu ◽

Li Fu Zhu ◽

Yan Ze Yu ◽

Chun Zi Na

Keyword(s):

Lipid Oxidation ◽

Ph Value ◽

Antioxidant Activities ◽

Ground Beef ◽

Thiobarbituric Acid ◽

Natural Antioxidants ◽

Inhibitory Effect ◽

Plate Count ◽

Refrigerated Storage ◽

Color Deterioration

The aim of this work was to determine the inhibitory effect of deer blood hydrolysates addition on lipid oxidation, color deterioration and microbial contamination of ground beef during during 9 days of refrigerated storage. The pH value, total plate count, thiobarbituric acid-reactive substances value (TBARS), total volatile basic nitrogen (TVB-N) and color were also determined. The results showed that the treatments added hydrolysates had significant inhibitory effects on lipid oxidation and kept the red color of ground beef in 9 days, when compared with controls (P < 0.05). Furthermore, the inhibitory effect enhanced as the adding level of the hydrolysates increased (P < 0.05). These results suggest that deer blood hydrolysates are good source of natural antioxidants.

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Nitrate removal from water by immobilized bacteria

Water Science & Technology Water Supply ◽

10.2166/ws.2017.075 ◽

2017 ◽

Vol 17 (6) ◽

pp. 1694-1702 ◽

Cited By ~ 1

Author(s):

Amos Nussinovitch ◽

Cheinat Zohar-Perez ◽

Zahi Rabinovitz ◽

Jaap van Rijn

Keyword(s):

Nitrate Removal ◽

Production Costs ◽

Agricultural Activity ◽

Refrigerated Storage ◽

Immobilized Bacteria ◽

Gel Beads ◽

Freeze Dried ◽

Porous Beads ◽

Removal Processes ◽

Physical And Chemical

Abstract Nitrate may reach surface and ground waters as a consequence of agricultural activity and discharge of domestic and industrial waste. Among the various methods used for nitrate removal, denitrification, a process in which nitrate is biologically reduced to elemental nitrogen, is relatively reliable and inexpensive as compared to other physical and chemical nitrate removal processes. Denitrification is generally conducted with biofilters in which bacteria are either immobilized to the surface of insoluble carriers or are entrapped within an immobilization matrix. We examined the use of non-toxic and biodegradable natural hydrocolloids for entrapment of denitrifying bacteria. Gel beads containing starch and alginate were used for this purpose. Three types of gel beads were examined: (1) wet gel beads; (2) porous wet gel beads; and (3) freeze-dried gel beads. With respect to nitrate removal, wet and dried gel beads showed similar removal capacities. Porous beads demonstrated an advantage over regular gel beads only during the first of the approximately 3-month incubation period. The viability of the immobilized bacteria was only slightly affected during prolonged refrigerated storage of the beads. Compared to freeze-dried beads, production costs of wet beads are significantly reduced, so it is anticipated that such carriers will eventually lead to a method that can be applied on an industrial scale.

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Extraction and Yield Optimisation of Fucose, Glucans and Associated Antioxidant Activities from Laminaria digitata by Applying Response Surface Methodology to High Intensity Ultrasound-Assisted Extraction

Marine Drugs ◽

10.3390/md16080257 ◽

2018 ◽

Vol 16 (8) ◽

pp. 257 ◽

Cited By ~ 21

Author(s):

Marco Garcia-Vaquero ◽

Gaurav Rajauria ◽

Brijesh Tiwari ◽

Torres Sweeney ◽

John O’Doherty

Keyword(s):

Response Surface Methodology ◽

Response Surface ◽

Antioxidant Activities ◽

Radical Scavenging ◽

Laminaria Digitata ◽

Ultrasound Assisted Extraction ◽

Antioxidant Power ◽

Assisted Extraction ◽

Freeze Dried ◽

Ultrasound Assisted

The objectives of this study were to employ response surface methodology (RSM) to investigate and optimize the effect of ultrasound-assisted extraction (UAE) variables, temperature, time and amplitude on the yields of polysaccharides (fucose and total glucans) and antioxidant activities (ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picryl-hydrazyl radical scavenging activity (DPPH)) from Laminaria digitata, and to explore the suitability of applying the optimum UAE conditions for L. digitata to other brown macroalgae (L. hyperborea and Ascophyllum nodosum). The RSM with three-factor, four-level Box-Behnken Design (BBD) was used to study and optimize the extraction variables. A second order polynomial model fitted well to the experimental data with R2 values of 0.79, 0.66, 0.64, 0.73 for fucose, total glucans, FRAP and DPPH, respectively. The UAE parameters studied had a significant influence on the levels of fucose, FRAP and DPPH. The optimised UAE conditions (temperature = 76 °C, time = 10 min and amplitude = 100%) achieved yields of fucose (1060.7 ± 70.6 mg/100 g dried seaweed (ds)), total glucans (968.6 ± 13.3 mg/100 g ds), FRAP (8.7 ± 0.5 µM trolox/mg freeze-dried extract (fde)) and DPPH (11.0 ± 0.2%) in L. digitata. Polysaccharide rich extracts were also attained from L. hyperborea and A. nodosum with variable results when utilizing the optimum UAE conditions for L. digitata.

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Interrelationship between secondary metabolites and antioxidant capacities of Centella asiatica using bivariate and multivariate correlation analyses

Applied Biological Chemistry ◽

10.1186/s13765-021-00656-9 ◽

2021 ◽

Vol 64 (1) ◽

Author(s):

Hyun Young Shin ◽

Hoon Kim ◽

Soontag Jung ◽

Eun-Jin Jeong ◽

Kyung-Haeng Lee ◽

...

Keyword(s):

Secondary Metabolites ◽

Antioxidant Activities ◽

Pearson Correlation ◽

Principal Component ◽

Centella Asiatica ◽

Multivariate Correlation ◽

Antioxidant Capacities ◽

Whole Plant ◽

Freeze Dried ◽

Ethanol Extracts

AbstractCentella asiatica L. Urban (CA) is a valuable medicinal herb that contains various bioactive secondary metabolites. In the present study, the harvested CA was divided into whole plant and leaf parts, and were heated-air-dried or freeze-dried. The dried CA was extracted under various extraction conditions to obtain 16 extracts, and their antioxidant activities were examined. Twelve types of secondary metabolites (five polyphenolic acids, four triterpenoids, and three flavonoids) were quantified in each extract. Finally, the intercorrelations between secondary metabolites and antioxidant activities were analyzed through statistical analyses, such as Pearson correlation coefficient, scatter plotting, and principal component analysis. The antioxidant capacities of CA might be primarily influenced by major triterpenoids such as madecassoside and asiaticoside, which showed high content in the ethanol extracts of freeze-dried leaf parts. The present study provides a valuable groundwork for the development of optimal extraction processes for C. asiatica L. as an antioxidant material.

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Effects of Enzymatic Liquefaction, Drying Techniques, and Wall Materials on the Physicochemical Properties, Bioactivities, and Morphologies of Zinc-Amaranth (Amaranthus viridis L.) Powders

International Journal of Food Science ◽

10.1155/2021/1819104 ◽

2021 ◽

Vol 2021 ◽

pp. 1-13

Author(s):

Siti Faridah Mohd Amin ◽

Roselina Karim ◽

Yus Aniza Yusof ◽

Kharidah Muhammad

Keyword(s):

Antioxidant Activities ◽

Gum Arabic ◽

Leafy Vegetables ◽

Drying Methods ◽

Cell Wall Degrading Enzymes ◽

Green Leafy Vegetables ◽

Enzymatic Liquefaction ◽

Freeze Dried ◽

Wall Materials ◽

Spray Dried

The demand for vegetable powder has been escalating considerably due to its various health benefits and higher shelf life compared to fresh green leafy vegetables. Thus, much research emphasised manufacturing vegetable powder at a lower operational cost and higher efficiency while preserving the nutritive values of the vegetables. In this study, zinc- (Zn-) amaranth puree was liquefied with three types of cell wall degrading enzymes (i.e., Viscozyme L, Pectinex Ultra SP-L, and Rapidase PAC) with varying concentrations (0–3% v/w) and incubation time (0.5–24 h) at pH 5 and 45°C before the drying process. The results showed that enzymatic liquefaction using 1% (v/w) of Viscozyme L for 3 h was the optimal procedure for the reduction of the viscosity of the puree. The liquefied puree was then microencapsulated through either spray- or freeze-drying with different wall materials, e.g., 10% of maltodextrin (MD) DE 10, resistant maltodextrin (RMD), N-octenyl succinate anhydride (OSA) starches from waxy maize, HI CAP 100 (HICAP), Capsul (CAP), and gum Arabic (GA). The results showed that all freeze-dried powders generally had higher process yield (except for that encapsulated by HICAP), higher moisture content (but similar water activities), higher retention of total Zn-chlorophyll derivatives, lower hygroscopicity with slab-like particles, larger particle size, and lower bulk density than those of spray-dried powders. In contrast, the spray-dried powders exhibited irregular spherical shapes with relatively high encapsulation efficiency and antioxidant activities. Nonetheless, encapsulation using different wall materials and drying methods had no significant effect on the powder’s cohesiveness and flowability.

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