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The use of carbon monoxide (CO) as a valuable feedstock for producing various platform chemicals through biorefinery processes has attracted considerable research interest. Acetate is an intermediate chemical synthesized from CO and CO2 through acetogenesis via the Wood–Ljungdahl pathway. Acetate can further serve as a substrate for chain elongation into a higher volatile fatty acid (VFA) when sufficient reducing power is provided. Zero-valent iron (ZVI) is used widely as a reducing agent in environmental remediation applications. This study established that the externally provided reducing power from ZVI oxidation increased the acetate production (approximately 13 times) from CO and the further synthesis of VFA. The effect of ZVI on CO/CO2 conversion was evaluated by quantifying the formation of acetate and butyrate. The carbon and electron balance provide information on the mechanism of C1 gas conversion and chain elongation. These findings highlight a useful intermediate production under the reducing power-limited bioprocesses, such as C1 gas bioconversion. [ABSTRACT FROM AUTHOR]

Effect of various ozonation durations (i.e., 15, 30, and 60 min) on selected properties of gum arabic with 0.5% concentration (db), corn starch (S) and corn starch-gum arabic dispersion (GAS) were investigated. Ozonation generally caused significant decrease in viscosity of samples (P < 0.05), providing potential ease of use in industry. Peak temperature of GAS was increased after 60 min ozonation (P < 0.05), as measured by differential scanning calorimeter. The pH values decreased after for each ozonation period (15, 30 and 60 min) (pH 5.0 to pH 2.50), due to possible hydroxyl oxidation by ozonation, which was linked to increased formation of carbonyl and carboxyl groups. It was observed that ozonation resulted in increased water solubility index whereas a decrease was observed in water adsorption index. Ozonation increased the quantity of reducing sugars (19.3%), phenolic compound concentrations (24.0%) and radical scavenging activity (48.0%) compared to control samples after 60 min ozonation. This study suggests that ozonation could be used to oxidize GAS dispersions by an environment friendly approach. [ABSTRACT FROM AUTHOR]

Oxidative stress that damages cellular components affects various organs including the brain. It is thus believed to play an active role in neurodegenerative diseases, wherein the intrinsic antioxidant enzymes metabolize toxic intermediates. For therapeutic purpose, instead of antioxidant enzymes, small organic compounds as antioxidants may be more effective. Here, reducing power and electrochemical behavior of some flavanols, flavanonols, flavones, flavonols and O–methylated flavonols have been estimated and confirmed by the calculated bond dissociation energy. Compared to other classes, flavonols exhibited increased reducing power that decreased with methylation of the oxygen atom in the B-ring. Gossypetin emerged as the most effective of these flavonols. Generally, compounds with two hydroxyl groups in two consecutive positions of the phenyl ring and an enolic group in the C-ring with more preference for the hydroxyl group in the ortho position with respect to each other in the catechol moiety showed major activity. 5 position of the A-ring showed the least effect on the activity. The present understanding therefore may be applied for identifying compounds to be used as scaffold for designing potent antioxidants. [ABSTRACT FROM AUTHOR]

Opuntia Ficus Indica (OFI) is widely cultivated in arid and semiarid areas of Tunisia and other parts of the world and reported to have sound biological activities. The current work aimed at investigating the effect of various solvent concentrations (80% acetone, 80% methanol and 80% ethanol) on extraction yield, total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity using three assays: DPPH, ABTS and FRAP and antibacterial activity of Red and yellow–orange (YO) OFI skin and pulp extracts. Results showed high content of polyphenols and flavonoids ranging from 3.046 to 86.287 µg GAE/mg DW and from 0.167 to 11.917 µg QE/mg DW respectively. Although pulp extracts had the highest extraction yield, skin extracts exhibited the highest TPC, TFC and antioxidant activity and in most cases the highest antibacterial activity. The 80% acetone extracts exhibited the lowest yield extraction but showed the highest TPC, TFC and the strongest antioxidant activity compared to the 80% methanol and 80% ethanol extracts except for Red pulp. Among all extracts, the 80% acetone YO skin extract showed the best TPC (86.287 µg GAE/mg DW), TFC (11.917 µg QE/mg DW). Moreover, it showed the highest antioxidant activity (DPPH IC50 = 0.784 mg/mL, ABTS IC50 = 0.829 mg/mL and FRAP EC50 = 1.285 mg/mL). The antibacterial activity tests showed that the 80% ethanol of YO skin extract had the most influence on the inactivation of the Gram-positive Enterococcus feacium bacteria type (zone of inhibition = 11.00 mm) compared to other extracts. In addition, the 80% acetone extracts showed better antibacterial activity compared to hydro-alcoholic extracts against other bacterial strains. [ABSTRACT FROM AUTHOR]

This study was aimed to develop the reduction process of natural indigo (Indigo/era tinctoria) by using bacterial strain (Dietzia sp. KDB1) separated from Korean traditional fermentation bath. In detail, changes in pH, oxidation reduction potential (ORP), and color intensity (K/S) of dyed ramie fabric were evaluated by using some of alkaline mediums, pH adjustments, and concentrations of KDB1 and indigo, respectively. In terms of pH control and reducing power, buffer solution of NaHCO3/NaOH was the most effective among the mediums used. In the baths with buffer solution, initial pH 10.7 exhibited faster initiation of reduction and higher K/S than other initial pH values. The bath adjusted at pH 10.0 showed higher K/S and more negative ORP, than the baths adjusted at pH 10.5 and 10.7. Better reducing power was obtained at higher indigo and KDB1 concentrations. With the combination of buffer solution, scale-up, repeat dyeing, and higher KDB1 concentration, K/S range of 9.5–16.0 was obtained at days of 4–6. Use of single bacterial strain for indigo reduction attains a simple, reliable and eco-friendly dyeing process which can be applied as an alternative to sodium dithionite reduction. [ABSTRACT FROM AUTHOR]

The aim of the present work was to find the changes in the chemical composition, chemical structure and antioxidant activity of bioactive nutrients of kiwi juices upon pasteurization and in vitro gastrointestinal digestion. Results showed that fresh kiwi juice (FKJ) contains total phenols, 162 mg GAE/mL, total flavonoids 1.44 mg QE/mL, ascorbic acid 4.5 mg/mL and fiber 60%; these contents were marginally affected by pasteurization (PKJ) to be 122, 1.02, 2.6 and 47 respectively. On the other hand, gastrointestinal digestion severely lowered total phenols, total flavonoids and ascorbic acid in digested fresh kiwi juice (DFKJ) to 49 mg GAE/mL,0.16 mg GE/mL and 2.2 mg/mL, and in digested pasteurized kiwi juice (DPKJ) to 42, 0.07 and 1.2 respectively; however fiber contents increased upon digestion as a result of decreasing other nutrients. The antioxidant and reducing power activities followed the same order of decreasing total phenols, total flavonoids and ascorbic acid contents i.e. FKJ > PKJ > DFKJ > DPKJ. The major flavonoid found was apigenin in the form of various glycosides differ in the number (1–3) and position of the sugar units. Pasteurization showed minor effects on the chemical composition of fresh juice while digestion, as a result of gastrointestinal enzymes had more effect but mainly on the number and position of the sugar units rather than affecting the flavonoid moiety which preserve the main nutritive values. [ABSTRACT FROM AUTHOR]

Biological activities of organoruthenium complexes [chloro [N,N′-[(2,6-pyridinediyl-κN) diethylidyne] bis-[benzenamine-κN]] [N-[(2-pyridinyl-κN) methylene] benzenesulfonamide-κN] ruthenium(II)] chloride (Cmplx 1), [chloro [2,2′-(2,6-pyridinediyl-κN) bis [1H-benzimidazole-κN3]][N-[(2-pyridinyl-κN) methylene] benzenesulfonamide-κN] ruthenium(II)] chloride (Cmplx 2), and [chloro[2,6-di(1H-pyrazol-3-yl-κN2) pyridine-κN] [N-[(2-pyridinyl-κN) methylene] [benzenesulfonamide-κN] ruthenium(II)] chloride (Cmplx 3) have been studies. The compounds were tested for in vitro biological activity on test models including 2,2-diphenyl-1-picryl-hydrazyl (DPPH) reducing power, superoxide anion radical-scavenging activity, and lipid peroxidation activity by ferric thiocyanate. It is established that Cmplx 2 with benzimidazole ligand displays significant xanthine oxidase inhibitory activity (IC50 = 53.80 ± 2.69 μM), DPPH free radical scavenging activity (79.49 ± 1.59), and superoxide anion radical scavenging activity (75.73 ± 2.85%). The coordination of benzenamine and benzenesulfanoamine ligands reduces lipid peroxidation as observed in the case of Cmplx 1 (87.17 ± 3.88%) and the higher reducing power of Cmplx 1 obtained at all concentrations. It was concluded from the test results that organoruthenium complexes showed much better antioxidant activity than expected. [ABSTRACT FROM AUTHOR]

Ultimate goal of this research is to develop an efficient microbial system for indigo reduction by using yeast (Saccharomyces cerevisiae). For this purpose, we investigated the effect of pH condition on natural indigo (Indigofera tinctoria) reduction by yeast. We also checked the viability of yeast at high pH condition by observing yeast cell in the indigo reduction bath with an optical microscope. The pH of indigo reduction bath was initially set from 10.2 to 12.0 with the buffer solution. The pH value dropped drastically up to 5.5–6.5 at the initial stage of reduction. After adjusting pH once within 1–2 days, we measured some parameters related to reducing power such as the color yield (K/S value) of ramie fabric dyed with the supernatant of bath, the oxidation/reduction potential (ORP), and the pH values changed. When the initial pH was set at lower than 11 (10.2, 10.7), the baths adjusted to pH 11 showed better reducing power than the baths of pH other than 11. And also, when the initial pH was set higher than 11 (11.3 and 12.0), the baths adjusted to pH 11 showed better reducing power than the baths of pH other than 11. It took 5–11 days to reach the maximum dye uptake after the initiation of reduction, and, during the corresponding time, the ORP was from -563 to -599 mV. All the initial and the adjusted pH values were not maintained but decreased continuously, and the maximum dye uptake reached at pH 9.17-9.43. The initial and the adjusted pH greatly affected the indigo reducing power, and the highest color yield was obtained with indigo reduction bath of initial pH 10.7. When the pH of the bath was adjusted to pH 11.0, the maximum reducing power was obtained most efficiently. Also, for the pH adjustment, use of sodium hydroxide showed higher reducing power than use of calcium hydroxide. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the effect of different extraction solvents and determine the optimum solvent concentration (in the range of 0–100%) for the recovery of total phenolic content, total flavonoid content and antioxidant capacity of peel, pulp and seed kernel of Mangifera odorata fruit. The total phenolic (TPC) and total flavonoid content (TFC) were determined using Folin–Ciocalteu and aluminum chloride assays, respectively. The highest level of TPC was found in 60% and 80% (v/v) acetone for pulp and seed kernel while peel showed the highest TPC at the concentration of 80% (v/v) acetone. The optimum total flavonoid content was achieved at 100% (v/v) methanol for all fruit parts. Antioxidant activity was measured using ferric reducing antioxidant power assay, and the result showed the highest activity at 60% (v/v) ethanol for all parts of M. odorata fruit. The highest scavenging activity was shown at 60% (v/v) acetone for pulp and seed kernel, respectively. Peel exhibited the highest scavenging activity at 40% acetone. It can be concluded that the recovery of phenolic compounds was dependent on the polarity of the chemical constituents in the different parts of fruit as well as the polarity of the solvent systems used. Seed kernel had the highest TPC, TFC and possessed excellent antioxidant capacity compared to peel and pulp of M. odorata. Therefore, the seed kernel can be incorporated into food products as a functional ingredient for the prevention of oxidative-stress related diseases. [ABSTRACT FROM AUTHOR]

This study was conducted to compare antioxidant contents and antioxidative activities in the leaves and petioles of six sweet potato varieties, namely Danjami, Hayanmi, Hogammi, Jinyulmi, Poongwonmi, and Yeonjami. Total amount of phenolic acids was highest in Poongwonmi and lowest in Hogammi, while vitamin C level was highest in Danjami. Of four phenolic acids quantified, 3,5-dicaffeoylquinic acid was the most abundant in all varieties. The contents of phenolic acids and vitamin C were more than ten-fold higher in the leaves compared with the petioles. In addition, the leaves had much lower EC50 values for DPPH scavenging activities and reducing power than the petioles, indicating that sweet potato leaves have a higher antioxidant capacity than the petioles. Blanching, including conventional and microwave, resulted in a considerable decrease of antioxidant content and activity in the leaves due to thermal degradation and leaching. [ABSTRACT FROM AUTHOR]

Carbon monoxide (CO) is one of the main waste gas components of the steel industry and biomass gasification process. CO has also been highlighted as a feedstock for biological conversion to platform and valueadded chemicals. Conventional CO-converting strains have drawbacks of slow growth rate and high sensitivity to oxygen as well as low conversion yield. Most CO conversion microbes harbor the Wood-Ljungdahl pathway (WLP) and CO-dehydrogenase, and the reducing equivalent is significantly limited for acetyl-CoA synthesis. In this study, electrochemically active CO converting strains were isolated and characterized using zero valent iron (ZVI) granules (Fe0) as an external electron donor. The strains isolated from ZVI augmented enrichment could also use a carbon electrode as the electron donor, and simultaneously convert CO to acetate and VFAs in a bioelectrochemical system. From enrichment and isolation with ZVI, both Clostridium sp. HN02 and Fonticella sp. HN43 were isolated and showed higher performance for acetate production from CO in BES, and electrochemical activity by cyclic voltammetry. [ABSTRACT FROM AUTHOR]

The present research evaluates the phytochemical and antioxidant activity of Moringa oleifera Lam. seed kernel grown in Bangladesh. M. oleifera seed kernel was extracted with methanol, acetone and water individually. The phytochemical content was evaluated through the determination of total phenolic, total flavonoid and total tannin contents. In vitro antioxidant capacity was determined following four complementary methods: DPPH (2,2-diphenyl-1-picrylhydrazyl, ABTS{2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid)}, and NO (nitric oxide) free radical scavenging and reducing power tests. The total phenolic contents 60.99 ± 0.153, 30.78 ± 0.101 and 90.97 ± 0.134 mg gallic acid eq./g dry extract, total flavonoids contents 10.13 ± 0.171, 13.32 ± 0.101 and 221.76 ± 0.221 mg quercetin eq./g and total tannins contents 97.10 ± 0.153, 73.91 ± 0.107 and 21.74 ± 0.086 mg gallic acid eq./g dry extract were found to be present in methanol, acetone and water extracts respectively. Among the three extracts, the water extract exhibited significant activities for scavenging DPPH, ABTS and NO free radicals with EC50 values 36.89 ± 0.154, 13.20 ± 0.049 and 217.95 ± 0.327 μg/mL respectively against the standard antioxidant compound ascorbic acid and butylated hydroxy anisole. The results of this research revealed that among the three extracts of M. oleifera seed kernel the water extract exhibited significant free radical scavenging activity. Reducing power, total phenolic and total flavonoid contents were also observed to be significant for the water extract. So in contrast of all the results of this study it can be concluded that among the three extracts (methanol, acetone and water) the water extract possessed potent antioxidant activity which support the use of M. oleifera seed kernel as natural antioxidant. [ABSTRACT FROM AUTHOR]

The genus Allium includes hundreds of plant species and is regarded as one of the most cultivated vegetables. It is an important source of novel therapeutic compounds known for their beneficial effects on human health; however, there could be differences in content, composition, type, and bioactivity of the phytochemicals found among the Allium plants. The main purpose of this study was to acquire insights on the variation in antioxidant profiles and phenolic content between Allium accessions in different species, as well as between similar species of several varieties. We collected 112 accessions from more than 20 countries, and grew them under similar agronomic conditions. The antioxidant potential was evaluated by using 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS), 1,1-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and reducing power (RP) assays. The total phenolic content (TPC) was studied using the Folin-Ciocalteu method. TPC varied from 3.43 (accession 199897) to 22.19 (accession 273483) µg gallic acid equivalent/mg dry weight (DW) of the aerial organs of Allium. The antioxidant activity of Allium samples ranged from 4.37 (accession 806595) to 57.46 (accession number 711971) µg Trolox equivalent/mg DW; 0.35 (accession 117246) to 9.53 (accession 711971) µg ascorbic acid equivalents/mg DW; 2.92 (accession 199890) to 21.20 (accession 803493) µgAAE/mg DW; and 0.80 (accession 117260) to 31.13 (accession 803527) µgAAE/mg DW using ABTS, DPPH, FRAP, and RP assays, respectively. Accessions 273483 (A. cepa), 283346 (A. cepa ‘cepa’), and 803527 (unknown species) had the highest TPC, FRAP, and RP values among those tested, while the highest ABTS and DPPH radical scavenging activities were recorded in accession 711971 (A. ramosum). Pearson’s coefficient of correlations indicated that variables (TPC, ABTS, DPPH, FRAP, and RP values) correlated significantly each other, with r-values between 0.585 and 0.894. Principal component analysis plots and hierarchical cluster analysis indicated significant variability in antioxidant activity and phenolic content among all the accessions studied, as well as within similar species. Based on our results from principal component and hierarchical cluster analysis, accession 283346 (A. cepa ‘cepa’), K139348 (A. fistulosum), and 711971 (A. ramosum) are potential sources of phenolics and natural antioxidants. The variability in total phenolic and antioxidant activity among the Allium accessions can be used by breeders, food technologists, nutritionist, and researchers for assessing breeding lines for genetic selection and for monitoring levels of these factors during food storage and processing. [ABSTRACT FROM AUTHOR]

Citrullus lanatus seed is a potential source of edible protein, hence effective extraction of protein components plays a vital role in food application. Therefore, this study aims for optimization and hydrolysis of protein using single factor and Box Behnken design (BBD). Various concentrations of the protein hydrolysates were studied for antioxidant activity using different assays. The one factor test revealed that important parameters such as alkali concentration (0.8%), temperature (40 °C), time (30 min) and solid to alkali ratio (1:30) enhance the protein concentration from C. lanatus (903.1 mg/g). The maximum degree of hydrolysis 39.30% was achieved at pH 2.4, an enzyme to substrate ratio 3% (w/w), and hydrolysis time 180 min by using BBD design. C. lanatus protein hydrolysate showed 15.71 and 61.67% of DPPH and ABTS radical scavenging activity at 5 mg/ml. It exhibited reducing power optical density 0.18 and metal chelating activity of 42.69% at the concentration of 25 mg/ml. This implied that C. lanatus could be used as a natural antioxidant agent. [ABSTRACT FROM AUTHOR]

Culture broth of Ganoderma lucidum was determined for antioxidant, antibacterial and α-amylase inhibitory activities. The culture broth contained protein as determined by Bradford method equaled to 0.2 mg/ml and total phenol content as 0.078 mg GAE/mg protein (0.557 mg GAE/g extract). It exhibited radicals scavenging activities against ABTS and DPPH radicals with a half maximal inhibitory concentration (IC) less than 1.70 ± 0.02 and 2.28 ± 0.02 µg protein/ml, respectively and reducing power equaled to 4.38 ± 0.02 µmol Trolox/µg protein as investigated by ferric ion reducing antioxidant power method. The culture broth experimented into two approached; (1) treated with pronase and (2) filtered through a membrane with 10 kDa molecular weight cut-off (MWCO). The pronase-treated culture broth exhibited insignificant lower antioxidant activities, but the retained culture broth 10 kDa MWCO resulted in significant decrease in antioxidant activities suggesting that the small proteins might play the key role in antioxidant activity. The culture broth could protect DNA damage from hydroxyl radicals (OH) generated by Fenton's reaction. This culture broth showed antibacterial activity towards pathogenic strains Staphylococcus epidermidis and Pseudomonas aeruginosa and also had an interesting α-amylase inhibitory activity. This study suggested that apart from the fruiting bodies and the mycelial of G. lucidum, its culture broth also had potential applications as a value-added ingredient in the product such as in cosmetics and in nutraceuticals. [ABSTRACT FROM AUTHOR]

The effects of heat treatment and extraction solvents (pure/aqueous acetone, ethanol, methanol) on antioxidant activity (AA) and components of clove (Syzygium aromaticum Linn) were studied. Clove was subjected to dry heat treatment (microwave and roasting) and the AA measured by free radical scavenging activity (FRSA), reducing power (RP), and phospho-molybdenum assay (TAA). Unheated samples served as controls. The antioxidant components estimated were total phenols, flavonoids and tannins. Using RP and FRSA, highest AA was observed in 80 % acetone extract of all samples (1.778-1448 and 84.5-86.0 %). TAA showed higher value in 80 % methanolic extract for all samples in the range 303.595-307.941 mmol ascorbic acid/g. Heated samples exhibited higher AA in all assays. Highest amount of phenols and flavonoids were extracted in 80 % acetone (4053-4064 mg/100 g) and 80 % methanol (11,271-11,370 mg/100 g) respectively. For tannins, maximum extraction was in 80 % acetone (control, 16441 mg/100 g), 80 % ethanol (microwave, 19,558 mg/100 g), and pure methanol (roasted, 15,823 mg/100 g). Total phenol and flavonoid contents were positively associated with AA determined using RP and FRSA. In conclusion, clove exhibited powerful AA in different extraction solvents which increased on dry heat treatments and correlated positively with antioxidant components. Hence, clove can be used as a natural antioxidant in food systems. [ABSTRACT FROM AUTHOR]

Reducing power such as NADH is an essential factor for acetone/butanol/ethanol (ABE) fermentation using Clostridium spp. The objective of this study was to increase available NADH in Clostridium beijerinckii IB4 by a microbial electrolysis cell (MEC) with an electron carrier to enhance butanol production. First of all, a MEC was performed without electron carrier to study the function of cathodic potential applying. Then, various electron carriers were tested, and neutral red (NR)-amended cultures showed an increase of butanol concentration. Optimal NR concentration (0.1 mM) was used to add in a MEC. Electricity stimulated the cell growth obviously and dramatically diminished the fermentation time from 40 to 28 h. NR and electrically reduced NR improved the final butanol concentration and inhibited the acetone generation. In the MEC with NR, the butanol concentration, yield, proportion and productivity were increased by 12.2, 17.4, 7.2 and 60.3 %, respectively. To further understand the mechanisms of NR, cathodic potential applying and electrically reduced NR, NADH and NAD levels, ATP levels and hydrogen production were determined. NR and electrically reduced NR also improved ATP levels and the ratio of NADH/NAD, whereas they decreased hydrogen production. Thus, the MEC is an efficient method for enhancing the butanol production. [ABSTRACT FROM AUTHOR]

Methylene blue undergoes reduction with an accompanying colour change reaction, from blue to colourless, enabling its use as a metric for estimating reducing power. A dye reduction-based electron-transfer activity monitoring (DREAM) assay is demonstrated as a tool to study and understand the process of microbes sourcing electrons from organic substrates and transferring them to an electron acceptor. The rate at which electrons can be transferred to the thermodynamically most feasible electron acceptor directly depends on the activity of microbes. Nature of available substrate determines the quantum of electrons available. Dissolved oxygen intercepts electrons from the microbes before they can be taken up by the dye. Sodium sulfite can be used to offset the detrimental effects of the presence of dissolved oxygen. This easy-to-perform assay has been demonstrated as a proof-of-concept having potential to be extended to other practical applications. [ABSTRACT FROM AUTHOR]

Green tea powder (GTP) was incorporated in wheat flour at different levels (1, 2 and 4 %) and its effect on quality parameters of flour and cookies were studied. Thermal analysis showed that addition of GTP did not increase the onset temperature, end temperature and enthalpy of flour significantly. However, the increase in GTP content retarded the retro gradation of the gelatinized wheat flour gel and decreased the water absorption capacity, Oil absorption capacity, water solubility index, Foam capacity and foam stability significantly. The L* and b* values of cookies decreased from 53.63 to 33.23 and 29.02 to 24.39 respectively, while as, a* value showed an increase from 3.61 to 5.23 indirect proportion to quantity added. The addition of GTP to wheat flour increased the DPPH (2,2-diphenyl-1-picrylhydrazyl) percent inhibition and reducing power of cookies. Further, it also increases the acceptability for color, aroma and taste; however it loosened its structural integrity and decreased the fracture force. [ABSTRACT FROM AUTHOR]

The free radical scavenging activity and reducing power of 16 phenolic compounds including four hydroxycinnamic acid derivatives namely ferulic acid, caffeic acid, sinapic acid and p-coumaric acid, benzoic acid and its derivatives namely protocatechuic acid, gallic acid and vanillic acid, benzene derivatives namely vanillin, vanillyl alcohol, veratryl alcohol, veratraldehyde, pyrogallol, guaiacol and two synthetic antioxidants, butylated hydroxy anisole (BHA) and propyl gallate were evaluated using 1,1-Diphenyl-2-picrylhydrazyl radical (DPPH), 2,2′-Azinobis-3- ethylbenzothiazoline-6-sulfonic acid radical (ABTS), Hydroxyl radical (OH) and Superoxide radical (O) scavenging assays and reduction potential assay. By virtue of their hydrogen donating ability, phenolic compounds with multiple hydroxyl groups such as protocatechuic acid, pyrogallol, caffeic acid, gallic acid and propyl gallate exhibited higher free radical scavenging activity especially against DPPH and O. The hydroxylated cinnamates such as ferulic acid and caffeic acid were in general better scavengers than their benzoic acid counter parts such as vanillic acid and protocatechuic acid. All the phenolic compounds tested exhibited more than 85 % scavenging due to the high reactivity of the hydroxyl radical. Phenolic compounds with multiple hydroxyl groups also exhibited high redox potential. Exploring the radical scavenging and reducing properties of antioxidants especially those which are found naturally in plant sources are of great interest due to their protective roles in biological systems. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the antioxidant properties and total phenolic compounds of a novel peanut-based kefir. HPLC was used to determine the composition of the peanut milk kefir extract. The antioxidant activity of kefir was measured by three methods: DPPH radical-scavenging activity, reducing power, and lipid peroxidation inhibition activity. As results, peanut milk kefir displayed greater antioxidant properties than the milk from which it was formed. Moreover, soluble phenolic content increased with the fermentation of peanut milk using kefir culture. Two groups of phenolics (phenolic acids and flavonoids) were found in peanut-based kefir extract. [ABSTRACT FROM AUTHOR]

Objective: To identify the free radical scavenging activity of ethanolic extract of Evolvulus alsinoides. Methods: The free radical scavenging activity was evaluated by in vitro methods like reducing power assay, total antioxidant activity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) reduction, superoxide radical scavenging activity, 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) scavenging activity, hydroxyl radical scavenging assay, and nitric oxide radical scavenging assay, which were studied by using ascorbic acid as standard. Results: The extract showed significant activities in all antioxidant assays compared with the reference antioxidant ascorbic acid. The total antioxidant activity as well as the reducing power was also found to increase in a dose-dependent manner. Conclusion: Evolvulus alsinoides may act as a chemopreventive agent, providing antioxidant properties and offering effective protection from free radicals. [ABSTRACT FROM AUTHOR]

Coumarins have been isolated from plants and reported for antioxidant properties. In the present study, we report synthesis of new coumarin derivatives as prospective therapeutic agents and investigate their antioxidant properties. [ABSTRACT FROM AUTHOR]

Basella rubra fruit juice with a total soluble solids content of 5 to 9 Brix was fermented using the wine yeast Saccharomyces cerevisiae. An 87.5 % of conversion of fermentable sugar was achieved. The TSS (Brix) reduced from 0.60 Brix to 0.17 Brix (71.67 % decrease in TSS) upon performing fermentation of fruit juice water extract with Saccharomyces cerevisiae strain 2. There was 8 folds reduction in pigment quality as evidenced from fermentation. Besides, the potential increase of phenolics, thanks to a higher content of total betalains in general and betacyanins in particular when fermentation was carried out with S. cerevisiae strain 3. The DPPH (2, 2 -diphenyl-1-picrylhydrazyl hydrate) free radical scavenging potential (IC) of fermented juice (1.9 mg.ml) was significant over control (2.4 mg.ml) extracts of B. rubra. The reducing power of fermented extracts was significantly high compared to control samples. The multiple antioxidant activity of fermented extract was also evident by significant reducing power assay when compared to its control samples. [ABSTRACT FROM AUTHOR]

Crude proteins of cultured mycelia and fruiting bodies of Ganoderma lucidum were investigated for antioxidant, antibacterial and DNA protective activities. It was found that the half maximal inhibitory concentration (IC) of the mycelia protein and fruiting bodies protein extracts against 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) radical (ABTS) were 2.47 ± 0.01 and 2.77 ± 0.11 μg protein/ml and against 2,2-diphenylpicrylhydrazyl radical (DPPH) were 2.5 ± 0.01 and 3.42 ± 0.01 μg protein/ml, respectively. The ferric reducing-antioxidant power (FRAP) values of those samples were 1.73 ± 0.01 and 2.62 ± 0.01 μmole trolox/μg protein respectively. Protein hydrolysates prepared by pronase exhibited a weaker antioxidant activity. Both crude proteins showed antibacterial activity, whereas only the mycelia protein extract could protect DNA damage by hydroxyl (OH) radicals. This protein extract was partial purified by Diethyl amino ethyl (DEAE)-Sepharose column and Sulfopropyl (SP)-Sepharose column, obtained major protein with molecular weight about 45 kilo Dalton (kDa). In conclusion, G. lucidum protein extracts have promise potential for applications as antioxidant and antibacterial agents. [ABSTRACT FROM AUTHOR]

l-lysine is made in an exceptional large quantity of currently 2,200,000 tons/year and belongs therefore to one of the leading biotechnological products. Production is done almost exclusively with mutants of Corynebacterium glutamicum. The increasing l-lysine market forces companies to improve the production process fostering also a deeper understanding of the microbial physiology of C. glutamicum. Current major challenges are the identification of ancillary mutations not intuitively related with product increase. This review gives insights on how cellular characteristics enable to push the carbon flux in metabolism towards its theoretical maximum, and this example may also serve as a guide to achieve and increase the formation of other products of interest in microbial biotechnology. [ABSTRACT FROM AUTHOR]

Edible parts of two varieties of date palm (Mazfati and Kalute varieties) ( Phoenix dactylifera) fruits (DPF) from Iran were analyzed to determine their phenolic compound and antioxidant activities (AA). Antioxidant activity evaluated using typical methods such as 2, 2-diphenyl-1-picrylhydrazyl (DPPH), reducing power and total antioxidant method. The total phenolic content (TPC) of the DPF was measured using Folin-Ciocalteau method. The samples used in this study included samples were gathered at three stages of khalaal, rutab, tamr and dried date from Bam and Jiroft date. The TPC ranged from 2.89 to 4.82, 1074 to 856.4 and 782.8 mg gallic acid equivalents (GAE/100 gdw sample) for khalal, rutab and tamr stage of Mozafati variety, respectively. This work demonstrates the potential of Iranian dates as good sources of antioxidant which can be used as functional food ingredients. The influence of sun drying process and oven drying at temperature ranged 50-80 °C on phenolic compounds and AA of date palm fruits were investigated. Result of drying process showed that TPC and AA varied with temperature and decreased by increase of drying temperature (from 667.3 to 610.5 mg galic acid in sun dried dates of Mozafati and Kaluteh respectively to 314.2 and 210.4 in dried dates (80 °C) of Mozafati and Kaluteh respectively). [ABSTRACT FROM AUTHOR]

Pomegranate seeds are byproducts of the Pomegranate juice industries that contains functional compounds such as phenols. This study was aimed to evaluate the effect of solvents on extraction from Pomegranate seed and Pomegranate defatted seed and to measure the yield extract and phenolic content and antioxidant properties. For this purpose, the seeds and defatted seeds were directly isolated from fruits and seeds by cold pressing respectively, then were crushed and extracted with different solvents, including water, Methanol, Acetone, Ethyl acetate and Hexane and finally the extracts of them were evaluted. Phenolic compounds, ferric reducing-antioxidant power and radicals scavenging property of extracts were measured. The results showed the highest extraction efficiencies were for Hexane and Acetone solvents in extraction of seed and defatted seed respectively. The highest phenolic content was obtained from Methanol seed extract. Reducing activity test proved that the Methanol extracts of Pomegranate seed and Pomegranate defatted seed had the highest reducing strength. Results of radical scavenging activity were similar to reducing activity results. The order of antioxidant capacity of Pomegranate seed and Pomegranate defatted seed were found to be Methanol > Water > Acetone > Butanol > Ethyl acetate > Hexane. It can be concluded Pomegranate seed, which possesses high levels of polyphenols, can be one of the sources of the natural antioxidants. The Methanol extract had a higher antioxidant efficiency than seed and defatted seed extracts. [ABSTRACT FROM AUTHOR]

In-vitro antioxidant activity of some food grains [ sprouted mung bean (Vigna radiata), mung bean, sprouted chana (Cicer arietinum), chana, corn (Zea mays), methi (Trigonella foenum-graecum) and rajma (Phaseolus vulgaris)] powder extracts (FGE) was estimated by DPPH free radical scavenging activity (SA) method. Total phenolics and reducing power were also estimated in these extracts. The antioxidant potential of these extracts was also estimated in a meat model system. Total phenolics in FGE ranged from 66.9 ± 3.4 to 248.6 ± 11.1 mg TAE/gdw respectively which differed significantly ( P < 0.01) among various groups. These extracts also showed remarkable DPPH radical scavenging activity (43.9 ± 1.1 % to 69.9 ± 2.9 %). The reducing power was observed maximum ( P < 0.01) in sprouted mung bean extract as compared to corn powder extract. The correlation between DPPH free radical SA v/s total phenolics was significant ( P < 0.01) with R = 0.775. correlation between DPPH free radical SA v/s reducing power and total phenolics v/s reducing power was also significant ( P < 0.01) with R value 0.907 and 0.682 respectively. FGE treated raw chicken breast meat showed better ( P < 0.01) oxidative stability than control groups. [ABSTRACT FROM AUTHOR]

Dried residues from four different vegetables, viz. pea pod (pp), cauliflower waste (CW), potato peel (PP) and tomato peel (TP) were extracted using four solvents i.e., hexane, chloroform, ethyl acetate and methanol. Among the four solvents, methanolic extracts showed the highest total phenolic content (TPC) for all the four vegetable residues. Methanolic extracts were evaluated for antioxidant activities using diphenylpicryl-hydrazyl (DPPH) and reducing power assay. Tomato peel extract showed highest phenolic content of 21.0 mg GAE/g-dw and 80.8 % DPPH free radical scavenging ability, whereas potato peel extract had a low phenolic content, and it also showed the least antioxidant activity among the residues examined in this study. Total phenolic content and DPPH free radical scavenging activity in pea pods and cauliflower waste were 13.6 mg GAE/g-dw and 72 % and 9.2 mg GAE/g-dw and 70.7 %, respectively. The coefficient of determination (r) for correlation between TPC and reducing power, DPPH and TPC, DPPH and reducing power for all extracts was 0.85, 0.91and 0.87, respectively, suggesting an important role of phenolics in imparting antioxidant ability. Extracts from vegetables residues therefore represent a significant source of phenolic antioxidants for use as nutraceuticals or biopreservatives. [ABSTRACT FROM AUTHOR]

Castilleja tenuiflora, a species highly valued for its medicinal properties, is threatened in the wild. We evaluated the effects of six different immersion cycles in a temporary immersion bioreactor on C. tenuiflora shoot growth, proliferation rate, phenolics content, flavonoid content, and antioxidant activity. We also evaluated the regeneration capacity of the shoots. The highest proliferation rate (nine shoots per explant) was obtained using an immersion cycle of 5 min every 12 h, and the longest shoots (38.8 ± 1.9 mm) were obtained using an immersion cycle of 5 min every 24 h. Shoots obtained from immersion cycles of 30 min every 24 h or 5 min every 24 h showed 100% rooting efficiency. Shoots obtained from immersion cycles of 30 min every 3 h or 30 min every 12 h accumulated HO, developed abnormal stomata, and showed symptoms of hyperhydricity. These characteristics were associated with a low survival rate (16-80%) when the plants were transferred to potting mix. The shoots from an immersion cycle of 30 min every 24 h showed the highest total phenolics content, which coincided with the highest antioxidant activity in the 2,2′-azinobis (3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS) free-radical scavenging assay (161.74 ± 10.06 μmol Trolox/g dry weight (DW)). The shoots from an immersion cycle of 5 min every 24 h showed the highest activity in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free-radical scavenging assay, and those from an immersion cycle of 5 min every 3 h showed the strongest reducing power. These results show that temporary immersion culture represents a reliable and efficient method for in vitro micropropagation of C. tenuiflora. [ABSTRACT FROM AUTHOR]

The antioxidant activity of thuja ( Thuja occidentalis) cones extract (TCE) and peach ( Prunus armeniaca) seeds extract (PSE) were estimated by DPPH free radical scavenging activity method. Total phenolics, total flavonoids and reducing power were also estimated in these extracts. Antioxidant potential of these by products was also evaluated in raw chicken ground meat (GM) during refrigerated (4 ± 1 °C) storage. Total phenolics in TCE and PSE were 7.80 ± 0.04 and 1.92 ± 0.04 mg TAE/gdw respectively. Both extract also showed remarkable DPPH radical scavenging activity (25.52 ± 1.92% and 24.99 ± 0.32%). The reducing power was observed more in TCE as compared to PSE (3.32 ± 0.01 and 0.49 ± 0.01). Total flavonoids contents were 7.48 ± 0.02 and 0.85 ± 0.01 mg CE/gdw respectively. Addition of these extract significantly ( P < 0.01) affected cooking losses and WHC of GM. During refrigerated storage (4 °C) the TBARS values at 8 d were significantly ( P < 0.01) more in control than TCE and PSE treated groups. [ABSTRACT FROM AUTHOR]

Antioxidants have recently become the topic of interest as radical scavengers, which inhibit lipid peroxidation and other free radical mediated processes. Chaetomium madrasense AUMC 9376 was isolated from Cairo soil and evaluated for antioxidant activity by various assays, such as DPPH, reducing power, scavenging activity by ferrous ion, nitric oxide (NO) and total phenolic content. Different physical and chemical conditions of the production medium were optimized for enhancement of antioxidant activity. The results revealed that incubation for 15 days at 25 °C and pH 6 was the most favorable for antioxidant activity. Moreover, both glucose and sodium nitrate were the proper carbon and nitrogen sources, respectively for the highest antioxidant activity. The extraction of the broth culture filtrate with different solvents revealed that ethyl acetate extract possesses the highest antioxidant activity. The obtained results suggest that the experimental fungus has the potentiality as a source of strong natural and safe antioxidants safe for application in the food and cosmetics industries. [ABSTRACT FROM AUTHOR]

The article describes the synthesis and characterisation of the Cr(III)-rutin complex along with an estimate of its antioxidant activity. The complex was characterised using elemental analysis, UV-VIS, IR, conductance data, thermal, and gravimetric analyses. In the UV-VIS study, a bathochromic shift of approximately 98 nm indicates the formation of a rutin complex by more than one chelating site. The FT-IR spectra clearly show the formation of the Cr-O bond between rutin and Cr(III) at 494 cm, while the thermal study shows the presence of eight coordinated water molecules in the complex. The gravimetric analysis quantitatively proves the presence of four chloride ions. From these data, the formula of the Cr(III)-rutin complex was deduced as [Cr(CHO)(HO)]Cl. Moreover, the antioxidant study of the complex was evaluated by using 2,2′-diphenyl-1-picrylhydrazyl (DPPH) free-radical, ferric-reducing, and phosphomolybdenum assays, which show that the complex has a higher antioxidant activity than rutin. [ABSTRACT FROM AUTHOR]

Phyllanthus fraternus is widely used in the cure of various liver diseases and possess antiviral properties especially against hepatitis virus. In the present study, evaluation of the antioxidant activity of stem and calli induced from stem has been done by different assays. Extraction was done by standard method in water and ethanol. Total antioxidant capacity was measured by 1, 1-diphenyl-2-picrylhydrazyl free radical scavenging method. Lipid peroxidation was measured in terms of thiobarbituric acid-reactive substances (TBARS) by using egg yolk homogenates as lipid-rich media, and superoxide radical scavenging activity was measured using riboflavin–light–nitro blue tetrazolium assay. Reducing power was determined on the basis of Fe 3+–Fe 2+ transformation in the presence of the extract. In addition to the antioxidant activity, polyphenolic compounds like total phenolics and flavonoids were also measured by spectroscopic method. Results showed that the ethanolic extract of stem is more potent in antioxidant activity than its aqueous extract and ethanolic extract of calli. A significant correlation between antioxidant capacity and polyphenolic content and reducing potential was observed, indicating that phenolic compounds and reducers present in extract are major contributors to the antioxidant potential. Thus, this plant extract could be used as a potent natural antioxidant. [ABSTRACT FROM AUTHOR]

The present study was designed to investigate the inflammatory and antioxidant activities of ethanolic leaf extract of Brownlowia tersa (L.) Kosterm. The anti-inflammatory activity of leaf extract was studied using carrageenan and histamine-induced rat paw edema test at different doses (200 and 400 mg/kg body weight). DPPH free radical scavenging, nitric oxide scavenging, reducing power, Fe ion chelating ability and total phenolic content were used for determining antioxidant activities. The extract, at the dose of 400 mg/kg, showed a significant anti-inflammatory activity ( P < 0.01) both in the carrageenan and histamine-induced edema test models in rats showing 54.76 % and 56.96 % reduction in the paw volume comparable to that produced by the standard drug indomethacin (64.88 % and 67.09 %) at 4 h respectively. In DPPH free radical scavenging test, IC value for ethanolic extract was found fairly significant 39.33 μg/ml when compared to the IC value of the reference standards ascorbic acid and Butylated Hydroxy Anisole (BHA) (3.16 and 5.81 μg/ml) respectively. The IC values of the extract and ascorbic acid were 99.06 and 39.35 μg/ml, respectively in nitric oxide scavenging assay. The maximum absorbance for reducing power assay was found to be 1.276 at 100 μg/ml when compared to 2.821 and 1.231 for standard ascorbic acid and BHA respectively. The IC value of the extract as percentage of Fe ion chelating ability was also found significant compared to that of EDTA. The total phenolic content was 211.82 mg/g of gallic acid equivalent. Acute toxicity test showed that the plant might be safe for pharmacological uses up to a dose level of 3,200 mg/kg of body weight in rats. Therefore, the obtained results suggest the acute anti-inflammatory and antioxidant activities of the ethanolic extract of Brownlowia tersa leaves and thus provide the scientific basis for the traditional uses of this plant part as a remedy for pain and inflammations. [ABSTRACT FROM AUTHOR]

Response surface method (RSM), based on Box-Behnken design, was used to optimize the enzymatic hydrolysis conditions of flatfish skin protein hydrolysates (FSPH). Among the tested proteases, the combination of nutrase and trypsin was selected. The optimal hydrolysis conditions were as follows: pH 7.3, temperature 51.8°C, and the enzyme/substrate (E/S) ratio 2.5; under these conditions, the maximum peptide yield (PY) was 69.41±0.43%. The physiochemical analysis showed that the amino acids (His, Asp and Glu) of FSPH accounted for 18.15%, and FSPH was a mixture of polypeptides mostly distributed among 900-2000 Da. FSPH could exhibit a 93% chelating effect on ferrous ion at a concentration of 400 μg/mL, and also a notable reducing power. This study showed bioprocess for the production of FSPH for the first time, which had a good potential for valuable ingredients in the food, cosmetic and medicine industries. [ABSTRACT FROM AUTHOR]

Anaerobic homofermentative production of reduced products requires additional reducing power (NADH and/or NADPH) output from glucose catabolism. Previously, with an anaerobically expressed pyruvate dehydrogenase operon ( aceEF- lpd), we doubled the reducing power output to four NADH per glucose (or 1.2 xylose) catabolized anaerobically, which satisfied the NADH requirement to establish a non-transgenic homoethanol pathway (1 glucose or 1.2 xylose ⇒ 2 acetyl-CoA + 4 NADH ⇒ 2 ethanol) in the engineered strain, Escherichia coli SZ420 (∆ frdBC ∆ ldhA ∆ ackA ∆ focA- pflB ∆ pdhR::pflBp6- pflBrbs- aceEF- lpd). In this study, E. coli SZ420 was further engineered for reduction of xylose to xylitol by (1) deleting the alcohol dehydrogenase gene ( adhE) to divert NADH from the ethanol pathway; (2) deleting the glucose-specific PTS permease gene ( ptsG) to eliminate catabolite repression and allow simultaneous uptake of glucose and xylose; (3) cloning the aldose reductase gene ( xylI) of Candida boidinii to reduce xylose to xylitol. The resulting strain, E. coli AI05 (pAGI02), could in theory simultaneously uptake glucose and xylose, and utilize glucose as a source of reducing power for the reduction of xylose to xylitol, with an expected yield of four xylitol for each glucose consumed (Y = 4) under anaerobic conditions. In resting cell fermentation tests using glucose and xylose mixtures, E. coli AI05 (pAGI02) achieved an actual Y value of ~3.6, with xylitol as the major fermentation product and acetate as the by-product. [ABSTRACT FROM AUTHOR]

The edible brown seaweed sugar Kombu ( Saccharina latissima) is a good source of dietary fiber (DF) and associated compounds. Besides it presents antioxidant capacity in vitro due to their sulfated polysaccharides and polyphenols. The effect of a DF-rich sugar Kombu diet on biochemical parameters and antioxidant and prebiotic effects in healthy rats was evaluated. Thus, rats were fed either a basal diet or a supplemented one with 10 % sugar Kombu for 4 weeks. Several health-promoting effects were found such as a decrease in triglycerides (TGL) and uric acid (UrA), and an increase in antioxidant status both in serum and cecum. Regarding prebiotic effect, higher cecum weight and total short chain fatty acid (SCFA) content were evidenced in the seaweed-fed group, without significant differences on total bacterial count of feces. Sugar Kombu and sulfated polysaccharides from its DF could be used as functional ingredients for further nutraceutical applications. [ABSTRACT FROM AUTHOR]

The content of total phenolic compounds and flavonoids was determined in methanol extracts of root, stem, leaves, and inflorescences from wild growing and greenhouse cultivated plants of Castilleja tenuiflora. The antioxidant activity in each extract was evaluated using three in vitro models: scavenging of free radicals with 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) diammonium salt (ABTS), and reducing power by the phosphomolybdenum assay. Both, antioxidant activity and phytochemicals content were influenced significantly ( P < 0.05) by the source of the plant material and the organ. Cultivated plants had the highest content of phenolic compounds (37.95 mg gallic acid equiv. g dry weight, P < 0.05) and the strongest antioxidant activity. Total phenolic compounds content correlated significantly with the antioxidant activity for all studied plant material and organs ( P < 0.05). TLC profile using DPPH as a detection reagent indicated that the phenylethanoids verbascoside and isoverbascoside are the main contributors to the free-radical scavenging of C. tenuiflora. Cultivated plants of C. tenuiflora are an alternative source of natural antioxidants to wild growing plants. The antioxidant properties of C. tenuiflora may be associated with its traditional use to treat conditions consistent with radical-related diseases (e.g. inflammation, tumors). [ABSTRACT FROM AUTHOR]

Anti-inflammatory and antioxidant activities of the crude ethanolic extract of the kernel root of Xylocarpus mekongenesis (Lamk.) M. Roem. (Meliaceae) was evaluated in different methods. The extract showed significant anti-inflammatory activity in carrageenan-induced oedema test in rats showing 69.42 % reduction in the paw volume ( P < 0.01) comparable to that produced by the standard drug indomethacin (70.25 %) at 24 h when the extract was fed at the dose of 400 mg/kg body weight. The percentage inhibition of the oedema paw volume was statistically significant ( p < 0.05) when compared with the indomethacin treated animals at 0.5, 1, 2, 4 and 6 h. The extract exhibited IC value 4.78 μg/ml in DPPH free radical scavenging activity test that was found to be very significant and comparable to that of the standard antioxidants ascorbic acid and BHA (1.9372 and 4.81 μg/ml) respectively. In nitric oxide radical scavenging test, the IC value was also found fairly significant 57.37 μg/ml when compared to standard ascorbic acid (36.81 μg/ml). In reducing power test, the maximum absorbance of the same extract was observed as 1.923 at 100 μg/ml and that of ascorbic acid and BHA were 2.8111 and 1.0314 respectively. The extract showed highest antioxidant capacity at 100 μg/ml concentration expressed as equivalents of ascorbic acid (1.44). The total phenolic content of the extract was also found quite high (342.15 ± 0.92 mg/g of gallic acid equivalent). Therefore, the results of this study suggest the probable anti-inflammatory and antioxidant activities of the ethanolic extract of X. mekongenesis kernel root and justify its use in traditional medicines. [ABSTRACT FROM AUTHOR]

The effects of pH control on the process of acetone/butanol/ethanol (ABE) production in batch cultures of Clostridium acetobutylicum XY16 have been investigated. Based on the specific acid- and solvent-forming rates in batch fermentation at different pH values (from 4.3 to 6.0), a two-stage controlled-pH strategy was developed in which the pH was shifted from 5.5 to 4.9 after a dry cell weight of 0.5 g L was achieved. By applying this strategy, the maximum ABE concentration and productivity reached 20.3 g L and 0.63 g L h , and were significantly improved by 12.2 and 40.1 %, respectively, compared with the process with no pH control. In addition, reducing power capability was significantly enhanced by this strategy. The two-stage controlled-pH strategy was a convenient and rapid method for high intensity ABE production. [ABSTRACT FROM AUTHOR]

Bioactive compounds in foods have been shown to maintain human health. However, the relative amounts of bioactive compounds and the variation in the amounts are still poorly understood. In this study, the efficacy of different extraction solvents (hexane, ethyl acetate, acetone, methanol, and a methanol:water mixture), as well as the levels of certain bioactive compounds in non-pungent pepper cultivars (TMH, TMJ, PA137, and B58) were investigated using high-performance liquid chromatography (HPLC). Antioxidant activities were determined using 2,2,-diphenyl-1-picrylhydrazyl (DPPH), reducing power, and deoxyribose degradation. Hexane extracts had the highest level of carotenoids (47.2-628.8 μg/g), and methanol extracts contained maximum flavonoids (24.9-152.2 μg/g) in four different cultivars. Higher DPPH scavenging activity was found in the hexane extracts from TMH, TMJ, PA137, and B58 (IC value: 0.67, 0.74, 0.55, and 0.48 μg/ml, respectively), whereas the reducing power was high in ethyl acetate and acetone extracts. Inhibition of deoxyribose degradation was highest in methanolic extracts from TMH, TMJ, PA137, and B58 (51.2, 49.5, 52.6, and 47.4 %, respectively). These data demonstrate that solvent chemical properties such as polarity can differentially impact the efficiency with which different bioactive compounds are recovered from foods, and this could lead to differences in estimated biological activity such as antioxidant capacity. [ABSTRACT FROM AUTHOR]

In this study, the antioxidant activities of juice, peel, and seed parts of pomegranate were investigated by using DPPH scavenging activity, β-carotene bleaching method, reducing power, and metal chelating activity. Sample of pomegranates which are named Punica granatum L. cv. Hicaznar, genotype 19-121, genotype 17-67, and genotype 19-66 obtained from BATEM (West Mediterranean Agricultural Research Institute) in Anlalya. The EC values of DPPH scavenging activities in peel extracts (PE) had 23.4-fold higher than the juice extracts (JE), and the seed extracts (SE) had 2.3-fold higher than JE. The reducing power in peel extracts was found to be 4.7-fold higher than SE and 10.5-fold higher than the JE. The highest metal chelating capacity (37.22%) was determined in peel, while the lowest (7.151%) in seed. Generally, in peel, the total polyphenol, flavonoid, tannin contents, and in juice, the total polyphenol, anthocyanin, tannin contents, and acidity significantly affected to antioxidant activities. [ABSTRACT FROM AUTHOR]

The development of antioxidants as useful drugs for the treatment of neurodegenerative diseases such as Alzheimer's is extremely challenging in medicinal chemistry. Coumarins have attracted great attention as possible therapeutic tools against oxygen radicals in human degenerative diseases. In order to establish the possible structure-antioxidant activity relationship, a series of twenty four 4-methylcoumarin derivatives were examined by employing reducing power measurements, and comparison with bond dissociation enthalpy and ionization potential calculations. Based on the reducing potency of 4-methylcoumarin derivatives with respect to trolox, these compounds were classified into five groups as "most active", "more active", "moderately active", "less active" and "inactive" derivatives. The presence of hydroxyl groups is an essential requirement for the activity, and substitution of hydroxyl groups by methoxy groups leads to non-active derivatives. The results revealed that dihydroxyl groups in the ortho position show a better antioxidant activity with respect to dihydroxyl groups in the meta position. This is ascribed to the ability to construct more stable 4-methylcoumarin radical intermediates by rearrangement of intra-molecular hydrogen bonding. Our findings indicate that other important factors to enhance the antioxidant activity of coumarins are the number of hydroxyl groups, the presence of ester substitutions and a thiono functional group on the pyrone ring. However, bond dissociation enthalpy and ionization potential calculations alone are not sufficient to identify the best antioxidant structures. As a result, chemical and functional properties of molecules such as 4-methylcoumarins should be examined as a whole entity, considering all substitutions versus a single substitution to design functional compounds with good antioxidant activity. [ABSTRACT FROM AUTHOR]

Effects of nutritional requirements for superoxide anion scavenging activity and reducing power by a newly screened Grifola frondosa TFRI1073 were studied in submerged cultures. The results clearly showed that the culture medium significantly affected superoxide anion scavenging activity and reducing power. In addition, both superoxide anion scavenging capability and reducing power were found to be greatly affected by varying the carbon source, the nitrogen source, the growth factor, and the mineral elements. The best superoxide anion scavenging activity could be obtained when the medium compositions (carbon source, nitrogen source, growth factor, and the mineral elements) were sucrose, ammonium chloride, nicotinic acid, KPO, and CuSO; while a maximal reducing power could be achieved when the medium composition setting as: xylose, arginine, ascorbic acid, KHPO, and MgSO. From a series experiments, the maximal superoxide anion scavenging activity and reducing power were 98.36±0.59% and 0.947±0.06 at 100 μg/mL, respectively. This study proved that modifying the composition of the medium can dramatically enhance the superoxide anion scavenging ability and reducing power by a newly screened G. frondosa TFRI1073. [ABSTRACT FROM AUTHOR]

Soups are consumed for nutritive benefits and also by patients whose intake of solids is considerably reduced due to several pathological reasons. Dehydrated soup mix is a convenient product due to its less volume and long storage life at ambient temperatures. Soup mix formulated with functional ingredients, modified potato flour (thickening agent), and dill leaf powder (DLP) was evaluated for its antioxidant properties. Aqueous and methanolic extracts of soup mix were prepared, and their total phenolic content, reducing power ability, and free radical-scavenging activity were determined. Significant improvement in total phenolics was observed as a result of addition of DLP that led to enhancement of its antioxidant properties. The phenolic acid profile of the soup mix base contained mainly tannic acid, while protocatechuic, gentisic, vanillic acid, and syringic acids were contributed by DLP. The reducing power ability of soup mix was increased by about 2.5 times in aqueous and about seven times in methanolic extracts, as a result of DLP addition. Concentration-dependent scavenging activity was observed, and IC50 (scavenging of 50% 1,1-diphenyl-2-picrylhydrazyl radical) values were reduced from 16.5 to 3.8 μg/mL in aqueous and from 9.1 to 3.9 μg/mL in methanolic extracts as a result of addition of DLP. The moisture–humidity relationship studies of soup mix conducted to determine its sorption behavior showed that the product exhibited caking tendency above 8.9% moisture corresponding to a critical relative humidity of 56%. [ABSTRACT FROM AUTHOR]

This study addressed the effect of hydrogen metabolism on cell growth and magnetosome synthesis in Magnetospirillum gryphiswaldense strain MSR-1. Two deletion mutants were generated: L206, with single deletion of the hupL gene encoding H2-uptake [NiFe] hydrogenase; and B206, with double deletion of the hyaB gene encoding H2-producing [NiFe] hydrogenase and the hupL gene. The wild-type and mutant strains were compared in terms of hydrogen uptake capability, hydrogen yield, growth rate, and iron uptake, and observed by transmission electron microscopy. Results indicate that HupSL protein is a specific H2-uptake hydrogenase while HyaAB protein is a specific H2-producing hydrogenase. In comparison to wild-type and B206, L206 released a greater quantity of H2 under conditions that induce magnetosomes synthesis, and showed higher rates of growth and iron uptake. M. gryphiswaldense appears to regulate reducing power in vivo, via H2-uptake hydrogenase and H2-producing hydrogenase, to promote iron absorption and magnetosome synthesis. [ABSTRACT FROM AUTHOR]

The spices used in the Indian foods such as Star anise ( Illicium verum), Bay leaves ( Cinnamomum zeylanicum) and Cobra’s saffron ( Mesua ferrea), and Acacia ( Acacia catechu), which have medicinal value, were used as test samples, to find their effect on in vitro lipid peroxidation (LPO). Rat liver post mitochondrial supernatant (PMS) in Tris HCl buffer, pH 7.4 was incubated for 0 and 1 h, with various test extracts in three different oxidant systems. The results show that addition of test samples to FeCl3 medium at 0 h significantly stop the initiation of the LPO. However, the propagation phase of LPO was inhibited by Cobra’s saffron and Acacia and not by Star anise and Bay leaves. The test samples also showed strong reducing power and superoxide radical scavenging activity. Cobra’s saffron and Acacia showed the highest antioxidant activity, probably due to the higher polyphenol content as compared to other test samples. [ABSTRACT FROM AUTHOR]

The article focuses on a study which investigated the antioxidant activity of Aralia elata seeds fractions. The antioxidant properties of dichloromethane, ethyl acetate, n-butanol and water fraction of 70% methanolic extract of A. elate seeds were determined using different antioxidant tests. The study found that ethyl acetate fraction exhibited the highest antioxidant potential among all the seeds fractions.