Antioxidant Activities Of Water Extracts Research Articles

Characterisation of phenolic acids, flavonoids, proanthocyanidins and antioxidant activity of water extracts from seed coats of marama bean [Tylosema esculentum] – an underutilised food legume

SummaryFreeze‐dried aqueous phenolic extracts with possible application as natural antioxidant functional food ingredients were prepared from marama bean seed coats by extracting with water. Phenolic acids, flavonoids and proanthocyanidins in the extracts were characterised by HPLC/MS. The major flavonoids were the flavanols methyl (epi)afzelechin‐3‐O‐gallate (40%) and methyl (epi)catechin‐3‐O‐gallate (28%), and the major phenolic acid was gallic acid (10%). Proanthocyanidins in the extracts were predominantly prodelphinidins composed of epicatechin‐3‐O‐gallate and epigallocatechin present as major terminal and extension units and epigallocatechin‐3‐O‐gallate and epicatechin present as minor extension unit constituents. The polymer structure was found to be unique compared with other legumes because of the high percentage of galloylated units. Extracts showed a high DPPH free radical scavenging activity (707 μmol TE g−1), protective effect against AAPH‐induced human red blood cell haemolysis and copper‐catalysed human LDL oxidation suggesting that the extracts may have potential health benefits.

IMPACT OF FERMENTATION DEGREE ON THE ANTIOXIDANT ACTIVITY OF PU-ERH TEA IN VITRO

ABSTRACT The consumption of pu-erh tea has been increasing rapidly in recent years. Pu-erh tea is considered to be much more beneficial to human health than other kinds of tea. Antioxidant activity is the main medicinal property of pu-erh tea. The present study compared the antioxidant activities of water extracts of tea (WEOT) and sun-dried green tea with different fermentation degrees in vitro. Antioxidant capacities of the WEOTs were evaluated by testing their total antioxidation capacity. The free radical scavenging capacity was evaluated using 1-1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assays, hydroxyl radical scavenging assays and superoxide anion free radical scavenging assays. Results showed that, of all the WEOTs, the first pile-fermentation tea sample gave the strongest scavenging ability of both DPPH radical and hydroxyl radical, followed by the sun-dried green tea, and DPPH radical scavenging activity was higher than that of hydroxyl radical. DPPH scavenging ability of the sun-dried green tea, the first, the second, the third and the fourth pile-fermentation tea were 87.90%, 89.29%, 85.86%, 82.62% and 80.94%, respectively. The scavenging ability of hydroxyl free radical for the WEOTs of the first pile-fermentation tea is significantly higher (P < 0.05) when compared with other extracts, with a 26.21% inhibition. The first pile-fermentation WEOT exhibited the most potent scavenging activity of superoxide anion free radical and total antioxidation capacity, while the fourth pile-fermentation WEOT had the lowest activity. The superoxide anion free radical scavenging activity and total antioxidation capacity of WEOTs had the most significant difference (P < 0.01) among the five tea samples. The results indicated that proper pile-fermentation process could enhance the antioxidant activity of pu-erh tea, whereas excessive pile-fermentation would provide the opposite effect. PRACTICAL APPLICATIONS Antioxidant activity is the main medicinal property of pu-erh tea. Pile-fermentation process is the key step which has the most important impact on antioxidant activity of pu-erh tea. It is believed that the antioxidant activity of tea depends on their fermentation degree. However, the correlation between pile-fermentation degree of pu-erh tea and its antioxidant activity is unknown. The objective of the present research was to investigate the effects of pile-fermentation of pu-erh tea on the antioxidant activity. The main results support the hypothesis that pu-erh tea with appropriate pile-fermentation degree could enhance the antioxidant activity. The results are very useful to further investigate the antioxidant component in pu-erh tea, and will help control the processing techniques and improve the health-care function of pu-erh tea.

Antioxidant Activity of Aqueous Extracts of Different Caffeine Products

The antioxidant activity of water extracts (cold and hot) of six caffeine products were carried out. The extracts were screened for total polyphenol contents and antioxidant activity using DPPH, ABTS methods and reducing power method at 50 and 100 μg/ml after 15 min and 30 min using DPPH, ABTS BHA and Caffeine as standard compounds. The results indicated that, the hot water extracts for different caffeine products showed higher antioxidant activity than those of cold extracts and this activity was time and concentration dependent. In addition, the activity was higher against ABTS radical more than DPPH and reducing power methods. Also, there is a positive correlation between the antioxidant and reducing compounds presented in water extracts of different caffeine products. The results of HPLC showed that fresh tea leaves are rich in flavanol monomers known as catechins. The most abundant catechin derivatives in green tea are EGC, EGCG and GC. On the other hand EGCG and GC are major catechin derivative in different caffeine product except El-Fakher tea and Cacao. Generally, these beverages had high antioxidant capacities and total phenolic contents, and could be important dietary sources of antioxidant phenolic for prevention of diseases caused by oxidative stress.

Chemical Compositions and Antioxidant Activities of Water Extracts of Chinese Propolis

The present study investigated the chemical composition and antioxidant activity of the water extract of propolis (WEP) collected from 26 locations in China. Spectrophotometry was used to determine the physicochemical properties and the chemical constituents of WEP. Phenolic compounds in WEP were identified by RP-HPLC-DAD with reference standards. The antioxidant activities [characterized by reducing power and 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging ability] of WEP were also measured. Results show that epicatechin, p-coumaric acid, morin, 3,4-dimethoxycinnamic acid, naringenin, ferulic acid, cinnamic acid, pinocembrin, and chrysin are the major functional phenolic compounds in Chinese WEPs. Furthermore, most WEPs show strong antioxidant activities, which are significantly correlated with E(1cm)(1%), an index for the estimation of the quality of WEP. WEPs also contain many more active constituents than ethanol extracts of propolis.

Antioxidant activity of aqueous extracts of different caffeine products

The antioxidant activity of water extracts (cold and hot) of six caffeine products were carried out. The extracts were screened for total polyphenol contents and antioxidant activity using DPPH, ABTS methods and reducing power method at 50 and 100 µg/ml after 15 and 30 min using BHA and Caffeine as standard compounds. The results indicated that, the hot water extracts for different caffeine products showed high antioxidant activity more than cold extracts and this activity was time and concentration dependent. In addition, the activity was higher against ABTS radical more than DPPH and reducing power methods. Also, there is positive correlation between the antioxidant and reducing compounds presented in water extracts of different caffeine products. The results of HPLC showed that fresh tea leaves are rich in flavanol monomers known as catechins. The most abundant catechin derivatives in green tea are EGC, EGCG and GC. On the other hand, EGCG and GC are major catechin derivative in different caffeine product except El-Fakher tea and Cacao. Generally, these beverages had high antioxidant capacities and total phenolic contents and could be important dietary sources of antioxidant phenolic for prevention of diseases caused by oxidative stress. Key words: Caffeine product, antioxidant activity, phenolic contents.

Antioxidant Activities of Extracts and Fractions from Eupatorium lindleyanum DC

The antioxidant activities of water extract (WE), ethanol extract (EE), residue water extract (RWE) and petroleum ether (PF), ethyl acetate (EF), n-BuOH (BF) and water (WF) fractions of the ethanol extract from Eupatorium Lindley DC were investigated for the first time. Total phenolics content, DPPH radical scavenging activities, superoxide radical scavenging activities, total reduction capability, and ferrous ions chelating activities were determined for all the extracts and fractions. The results showed that all the extracts and fractions exhibited antioxidant activities with different magnitudes of potency. Among all the samples, WE and RWE exhibited the best antioxidant capacities, the BF also exhibited high antioxidant abilities in all tests except for the metal chelating activity, while the other extracts and fractions were relatively weak antioxidants. The BF had the highest total phenolics contents in all extracts and fractions, and the WE and RWE were found to be rich in tannins. Furthermore, the content of total phenolics showed good correlation with DPPH radical scavenging activity, superoxide anion radical scavenging activity, and the reducing power. Phenolic composition of all the extracts and fractions was identified and quantified by HPLC. The results indicate that the extracts of E. Lindley DC might be a useful potential source of natural antioxidant ingredients.

Antioxidant activity of water extracts from fruit body of Lentinus edodes enriched with selenium

Shiitake (Lentinus edodes) belongs to medically important and delicious fungi. It is recognizable for its healing properties, excellent taste and rich aroma. According to the traditional Japanese and Chinese medicine, shiitake mushroom significantly increases the strength and vitality of the body. Shiitake contains immunostimulants, compounds that lower cholesterol, prevents clogging of blood vessels, regulates the pressure, balances blood sugar levels, regulates digestion, and improves the performance of respiratory organs by its antirheumatic and antiallergic activities. Shiitake is recommended to use as food, prevention and cure, usually in a form of a spice (dried and ground) or tea. It can be consumed fresh, too. The objective of this study was to test the effect of enrichment in selenium on antioxidant, reducing and free radical scavenging activity of water extracts from fruit body of Lentinus edodes. The fungus was enhanced by adding organic selenium, zinc (II) complex with the ligand 2.6-bis diacetylpyridine (selenosemicarbazon) and inorganic compounds (Na2SeO3) of selenium in nutritional substrate where the fungus was grown. The total selenium content in fruit body was around 50 ppm for the sample enriched with selenium originating from organic sources, and 80 ppm for the sample enriched with selenium from inorganic sources. Samples were prepared by extraction of fruiting bodies in heated water. The results indicated that water extracts of whole fruit bodies, from both control and mushrooms supplemented with selenium, had quite good antioxidant activity. However, there was no significant difference between the samples supplemented with selenium content and those that were not.

상백피 물 추출물의 항산화 활성 및 항천식 효과

This study was performed to evaluate the antioxidant activities and anti-asthma effects of Morus bark water extracts. Inhibitory effect of Morus bark onto free radical generation was determined by measuring DPPH and hydroxyl radical scavenging activities in vitro. Anti-asthma activities of Morus bark water extracts were assessed by testing their effects on the degranulation of mast cell. For this, β-hexosaminidase released from a basophilic cell line, RBL-2H3 was used and pro-inflammatory cytokines were measured by ELISA kit. The antioxidant activities of water extracts of Morus bark was 59.2% in the DPPH assay at 2,000 ㎍/mL and 78.8% in the hydroxyl radical scavenging assay at 2,000 ㎍/mL. Our results indicated that Morus bark water extracts effectively inhibited free radical generation. Morus bark water extracts inhibited inflammation-mediating substances such as histamine and β-hexosaminidase release from RBL-2H3 cells. Cytokine release demonstrated a more effective blockading ability of the Morus bark water extracts to the release of IL-4 and TNF-α compared to control. These results demonstrate that Morus bark may be beneficial in the treatment of allergic inflammatory disease.

The thermostability, bioactive compounds and antioxidant activity of some vegetables subjected to different durations of boiling: Investigation in vitro

This research was performed in order to compare the water and acetone extracts of raw and boiled for 10, 20, 40 and 60 min Korean lotus roots (KLR) and Polish white onion (PWO) in the contents of their bioactive compounds, antioxidant activity and thermostability. It was found that polyphenols (mg GAE/g), flavanols (μg GAE/g), flavonoids (mg CE/g), anthocyanins (mg CGE/kg) and tannins (mg CE/g) in water extract of raw lotus roots were 14.18 ± 0.7, 8.41 ± 0.5, 1.09 ± 0.06, 21.3 ± 1.2 and 7.29 ± 0.4, and of white onion – 11.11 ± 0.6, 6.78 ± 0.3, 0.71 ± 0.03, 17.00 ± 0.9 and 1.64 ± 0.08, respectively, and significantly higher in KLR ( P < 0.05). The antioxidant activity of raw KLR water extract (139.4 ± 6.1, 53.1 ± 3.6 and 89.3 ± 4.6 μmol TE/g for DPPH, CUPRAC and ABTS, respectively) was significantly higher than in white onion (23.84 ± 1.8, 31.9 ± 2.1 and 38.14 ± 2.6 for DPPH, CUPRAC and ABTS, respectively, P < 0.05). The thermostability of the water KLR extract’s of polyphenols, flavanols, flavonoids, anthocyanins and tannins was high and even after 60 min of boiling remains as 40.0, 42.3, 50.5, 41.4 and 41.0%, respectively. After 60 min of boiling the most thermostable compounds were flavonoids – remaining at 50.5% in water extract of KLR. Also after 60 min of boiling the thermostability of the antioxidant activity of water extracts of KLR remained significantly high: 40.6, 42.3, 46.3 and 43.6%, according to DPPH, FRAP, ABTS and CUPRAC assays, respectively. Similar relationship was obtained with acetone extracts, but the value was lower than with the water ones. In conclusion, the contents of some bioactive compounds, the antioxidant activity and the thermostability in water and acetone extracts of KLR are significantly higher than the same indices in PWO. FTIR and fluorimetry can be used as additional markers for the characterization of bioactive compounds in vegetables.

Antioxidant and antiacetylcholinesterase activities of chard ( Beta vulgaris L. var. cicla)

Plants have been used for many years as a source of traditional medicine to treat various diseases and conditions. Many of these medicinal plants are also excellent sources for phytochemicals, many of which contain potent antioxidant and antiacetylcholinesterase activities. Chard ( Beta vulgaris L. var. cicla) is widely spread in Turkey and used as an antidiabetic in traditional medicine. In the present study, the antioxidant activity and acetylcholinesterase inhibitor capacity of chard were examined. In addition, proline level of chard was determined. The antioxidant activity of water extract of chard was evaluated using different antioxidant tests. The results were compared with natural and synthetic antioxidants. The results suggest that chard may provide a natural source of antioxidant and antiacetylcholinesterase activities and proline content.

장기저장을 위해 제조한 동결건조 산채 블록의 항산화 활성 변화

곰취(Ligularia fischeri, GC), 고추잎(Capsicum annuum L., GCY), 취나물(Aster scaber, CNM), 머위대(Petasites japonicus S. et Z. Max, MYD) 및 고구마순(Ipomoea batatas L. (Lam), GGM)과 같은 산채들의 물 추출물의 항산화 능력을 평가하고 이들 동결건조 블록 물 추출물들의 항산화력과 비교하였다. 산채 물 추출물들과 그들의 동결건조 블록물 추출물들의 항산화력 측정은 2,2-diphenyl-1-picrylhydrazyl(DPPH) radical 소거작용, hydroxyl radical 소거작용 및 아질산염 소거작용과 같은 방법에 의해 알아보았다. 산채 물 추출물은 그들의 동결건조 물 추출물보다 총 페놀함량이 더 높았다. GC, GCY, CNM, MYD 그리고 GGM 물추출물들의 총 페놀 함량은 각각 471.66±3.52 ㎍/㎎, 141.33±2.51 ㎍/㎎, 177.33±2.88 ㎍/㎎, 238.66±9.50 ㎍/㎎ 그리고 122.67±3.51 ㎍/㎎이었다. 1000 ppm GC, GCY, CNM 그리고 GGM 물 추출물의 DPPH radical 소거작용은 그들의 동결건조 블록 물 추출물보다 더 높았고, 1000 ppm CNM, GC, GCY, MYD 그리고 GGM의 물 추출물의 DPPH radical 소거작용은 각각 90.9%, 89.9%, 76.6%, 71.1% 그리고 57.4%였다. 10000 ppm GC, GCY, CNM, MYD 그리고 GGM 물 추출물들은 hydroxyl radical 소거작용을 각각 38.8%, 33.4%, 35.9%, 34.3% 그리고 33.8%까지 증가시켰고, GCY, CNM 그리고 GGM의 물 추출물은 동결건조 블록 물 추출물과 유사한 활성을 나타내었으나 GC와 MYD의 물 추출물이 이들 동결건조 블록들의 물 추출물의 hydroxyl radical 소거작용보다 약간 더 영향력이 있었다. 산채 물 추출물들과 이들 동결건조 블록 물 추출물들은 실험된 모든 농도에서 DPPH radical 소거작용 및 hydroxyl radical 소거작용을 나타내었다. GC 물 추출물의 아질산염 소거작용은 현저하게 농도 의존적으로 증가하였고, GC 물 추출물의 아질산염 소거작용이 그것의 동결건조 블록 물 추출물의 아질산염 소거작용보다 높았다. 이상의 결과들로부터 동결건조블록이 산채와 비교하여 산채가 가지고 있는 항산화력을 유지하고 있다는 것을 알수 있었다.

In vitro Antioxidative Activities and Phenolic Composition of Hot Water Extract from Different Parts of Cudrania tricuspidata

We evaluated total phenolics and antioxidative activities of water extracts from different parts of Cudrania tricuspidata (specifically, the leaves, stems, roots, and fruits). The antioxidative activities of these samples were determined using five methods, including 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) radical scavenging, reducing power, ferric reducing ability of plasma (FRAP), and β-carotene/linoleic acid system. The water extract of leaves exhibited the higher DPPH, ABTS radical scavenging activities, reducing power, and FRAP than water extract of stem, roots, and fruits. Inhibition values on linoleic oxidation of water extracts from leaves, stems, roots, and fruits were calculated as 45.98%, 33.03%, 39.73%, and 25.48% at 10 ㎎/mL, respectively. The water extract of C. tricuspidata leaves had the highest amount of toal phenolics (73.60±0.28 ㎎/g). High-performance liquid chromatography (HPLC) analysis showed that quercetin is the predominant phenolic compound in water extract of leaves. Thus, our study verified that the water extract of leaves has strong antioxidant activities which are correlated with its high level of phenolic compounds, particularly quercetin. This water extract of C. tricuspidata leaves can be used as an effective and safe source of antioxidants.

Antioxidant and Immunity Activity of Water Extract and Crude Polysaccharide from Ficus carica L. Fruit

The antioxidative activities of water extract (WE) and crude hot-water soluble polysaccharide (PS) from Ficus carica L. fruit were investigated using various assays in vitro, including scavenging abilities on DPPH, superoxide and hydroxyl radicals and reducing power. The immunity activities of PS were evaluated using the carbon clearance test and serum hemolysin analysis in mice. In addition, total phenolics and flavonoids contents were also determined. Both WE and PS have notable scavenging activities on DPPH with the EC(50) values of 0.72 and 0.61 mg/ml, respectively. The PS showed higher scavenging activity than WE on superoxide radical (EC(50), 0.95 mg/ml) and hydroxyl anion radical (scavenging rate 43.4% at concentration of 4 mg/ml). The PS (500 mg/kg) also has a significant increase in the clearance rate of carbon particles and serum hemolysin level of normal mice. The results indicate that both WE and PS might be applicable in healthy medicine and food industry.

Antioxidant activities of extracts and fractions from Lysimachia foenum-graecum Hance

The antioxidant activities of water extract, methanol extract, ethyl acetate, and n-BuOH fractions of methanol extract from Lysimachia foenum-graecum Hance were investigated in this study. Various methods, such as the total antioxidant capacity measured by phosphomolybdenum method, scavenging activities towards 1,1-diphenyl-2-picryhydrazyl (DPPH) radical, superoxide anion radical, and hydroxyl radical, were established in in vitro systems. The amounts of total phenolics and total flavonoids in the extracts and fractions were also determined by spectrophotometric methods. The results showed that all the extracts and fractions exhibited antioxidant and radical-scavenging activities at different magnitudes of potency. The decreasing order of antioxidant and radical-scavenging activities among the extracts assayed through all the four methods were found to be ethyl acetate fraction>n-BuOH fraction>methanol extract>water extract. This similar order of the amounts of total phenolics and total flavonoids shows that the extent of antioxidant and radical-scavenging activities is in accordance with the amounts of phenolics and flavonoids present in extracts and fractions. The extracts of L. foenum-graecum Hance might be valuable antioxidant natural sources and seemed to be applicable in both healthy medicine and food industry.

Antioxidant Activity of Water Extract of Propolis from Different Regions In Kafr El-Sheikh Governorate

Antioxidant Activity of Water Extract of Propolis from Different Regions In Kafr El-Sheikh Governorate

Antioxidant activity of water and alcohol extracts of Thuja orientalis leaves

Water and alcohol extracts were prepared from dried and powdered leaves of Thuja orientalis (T. orientalis). The reducing power, total phenolic content, the 1,1-diphenyl-2-picrylhydrazyl scavenging activity, inhibitory effect on Fe (II)-EDTA-<TEX>$H_{2}O_{2}$</TEX> (Fenton reaction system) induced DNA damage and inhibitory effect on human red blood cell (RBC) hemolysis were evaluated in the present study. At a concentration of 200 mg, water and alcohol extracts of T. orientalis inhibited the hydrolysis of DNA by 72.859% and 65.312%, respectively. Water and alcohol extracts of T. orientalis also inhibited 2,2'-Azobis(2-amidinopropane) dihydrochloride induced RBC hemolysis to the extent of 69.30% and 54.55%, respectively. The reducing power and antioxidative activity of water extract was found to be more than that of alcohol extract. This is attributable to the presence of higher amount of phenolic compounds in water extract. The present results indicate that the T. orientalis extracts are rich sources of natural antioxidants and can protect DNA and human red blood cells against free radical induced oxidative damage.

Antioxidant activity of extracts from Acanthopanax senticosus

Antioxidants play an important role in inhibiting and scavenging radicals, thus providing protection to humans against infectious and degenerative diseases. Literature shows that the antioxidant activity is high in medicinal plants. Realizing the fact that, this study was carried out to determine the antioxidant activity of water extract of Acanthopanax senticosus. Water extract (0.5 g/50 ml) of A. senticosus (ASE) were prepared and total phenol contents (TPC) and radical scavenging activity (RSA) of the extracts was determined for antioxidant activity. The TPC and RSA of ASE were 366.67
M and 67.67%, respectively. In addition, the effect of ASE on DNA damage induced by H2O2 in human lymphocytes was also evaluated by Comet assay. The ASE showed strong inhibitory effect as its concentration increased from 0.125 to 1% by 65 to 81% against DNA damage induced by 200
M of H2O2. These results suggest that water extract of commercial dried A. senticosus for tea showed significant antioxidant activity and protective effect against oxidative DNA damage.

Antioxidant activity of extracts from Acanthopanax senticosus

Antioxidants play an important role in inhibiting and scavenging radicals, thus providing protection to humans against infectious and degenerative diseases. Literature shows that the antioxidant activity is high in medicinal plants. Realizing the fact that, this study was carried out to determine the antioxidant activity of water extract of Acanthopanax senticosus. Water extract (0.5 g/50 ml) of A. senticosus (ASE) were prepared and total phenol contents (TPC) and radical scavenging activity (RSA) of the extracts was determined for antioxidant activity. The TPC and RSA of ASE were 366.67
M and 67.67%, respectively. In addition, the effect of ASE on DNA damage induced by H2O2 in human lymphocytes was also evaluated by Comet assay. The ASE showed strong inhibitory effect as its concentration increased from 0.125 to 1% by 65 to 81% against DNA damage induced by 200
M of H2O2. These results suggest that water extract of commercial dried A. senticosus for tea showed significant antioxidant activity and protective effect against oxidative DNA damage.

Spectrophotometric method for the study of the antioxidant activity applied on Ziziphus jujuba and Hydrangea paniculata aqueous extract

Antioxidant activity of water extracts from Ziziphus jujuba fruits and Hydrangea paniculata leaves, maintained in a refrigerator, was determined by the potassium permanganate method. The results presented in this paper indicate that the fruit extracts from Ziziphus jujuba had higher antioxidant activity than Hydrangea paniculata leaf extracts and that both fermentation processes had a strong effect on antioxidant activity.

Antibacterial and Antioxidant Activities of Banana (Musa, AAA cv. Cavendish) Fruits Peel

The fresh green and yellow banana peel of, (Musa, cv. Cavendish) fruits were treated with 70% acetone, which were partitioned with chloroform (CHCl3) and ethyl acetate (EtOAc), sequentially. The antioxidant activities of the extracts were evaluated by using the thiocyanate method, β-carotene bleaching method and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical elimination. While, antimicrobial activities of the extracts and isolated components were evaluated using paper disc methods and Minimum Inhibition Concentration (MIC). The EtOAc and water soluble fractions of green peel displayed high antimicrobial and antioxidant activity, respectively. Antioxidant activity of water extracts was comparable to those of synthetic antioxidants such as butylated hydroxyanisole and butylated hydroxytoluene. Among all isolated components β-sitosterol, malic acid, succinic acid, palmatic acid, 12-hydroxystrearic acid, glycoside, the d-malic and 12-hydroxystrearic acid were the most active against all the Gram-negative and positive bacterial species tested. The MIC of d-malic and succinic acid was varying between 140-750 ppm, respectively.