20 research outputs found
Effects of drying on cholinesterases and angiotensinâI converting enzyme inhibitory potential and phenolic constituents of African mistletoe (Loranthus bengwensis L) leaves from kolanut host tree
This study investigated the most appropriate drying method (sun drying, oven drying, and shade drying) for mistletoe leaves obtained from kolanut tree. The phenolic constituents were characterized using high performance liquid chromatographyâdiode array detector, while the inhibitory effect of the aqueous extracts of the leaves on cholinesterases and angiotensinâI converting enzyme (ACE) and antioxidant activities were determined in vitro. The extracts inhibited acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and ACE in doseâdependent manner. However, extract from sunâdried sample exhibited the highest AChE, BChE, and ACE inhibitory effect while extract from shadeâdried sample had the least. Likewise, sunâdried sample exhibited the highest antioxidant properties as exemplified by Fe2+âchelating, 1,1âdiphenylâ2 picrylhdrazyl, OH, and nitric oxide radical scavenging abilities. This study also revealed the presence of 20 phenolic compounds with caffeic acid being the most predominant. Conclusively, kolanut host tree mistletoe leaves can be used as therapeutic agent in the management of Alzheimer's disease and hypertension
Inhibition of key enzymes linked to type 2 diabetes and sodium nitroprusside-induced lipid peroxidation in rat pancreas by water-extractable phytochemicals from unripe pawpaw fruit (Carica papaya)
Background: Various parts of unripe pawpaw (Carica papaya Linn) fruit have been reportedly used for the management or treatment of diabetes mellitus in folklore medicine. Therefore, the present study sought to investigate the inhibitory effects of the aqueous extract of different parts of unripe pawpaw fruit on key enzymes linked to type 2 diabetes (α-amylase and α-glucosidase) and sodium nitroprusside (SNP)-induced lipid peroxidation in rat pancreas in vitro.
Methods: The aqueous extracts of the unripe pawpaw (C. papaya) fruit parts were prepared (1:20 w/v) and the ability of the extracts to inhibit α-amylase, α-glucosidase and SNP-induced lipid peroxidation in rat pancreas in vitro was investigated.
Results: The results revealed that all the extracts inhibited α-amylase (IC50=0.87â1.11 mg/mL), α-glucosidase (IC50=1.76â2.64 mg/mL) and SNP-induced lipid peroxidation (IC50=1.99â2.42 mg/mL) in a dose-dependent manner. However, combination of the flesh, seed and peel in equal amounts had the highest inhibitory effect on α-amylase and α-glucosidase activities.
Conclusions: Strong inhibitory activities of the unripe pawpaw fruit against key enzymes linked to type 2 diabetes and SNP-induced lipid peroxidation in rat pancreas could be part of the mechanism by which unripe pawpaw is used in the management/prevention of diabetes mellitus in folk medicine. However, combining the unripe pawpaw fruit parts in equal amounts exhibited synergistic properties on α-amylase and α-glucosidase inhibitory activitie
Impact of drying processes on Bryophyllum pinnatum phenolic constituents and its antiinflammatory and antioxidative activities in human erythrocytes
The effect of drying on the phytoconstituents, antioxidative, and anti-inflammatory properties of
Bryophyllum pinnatum leaves was investigated. The phenolic constituents were characterized using
HPLC-DAD. The aqueous extraction was done and various assays (Inhibition of membrane stabilization,
albumin Denaturation and heatinduced hemolysis, malondialdehyde (MDA), and reduced glutathione
(GSH) contents, as well as superoxide dismutase (SOD) activity), were carried out on human
erythrocytes. The fresh portion (89.12 ”g/ml) exhibited the highest potential to inhibit heat-induced
hemolysis compared to the standard drugâDiclofenac (91.51 ”g/ml). Freeze-dried sample showed the
highest inhibitory potential on albumin denaturation ([Freeze-dried-330.72 ”g/ml], [Diclofenac-318.63
”g/ml]) and membrane destabilization ([Freeze-dried-331.93 ”g/ml], [Diclofenac-289.57 ”g/ml]) when
compared with Diclofenac. Similarly, the freeze-dried sample showed the highest GSH and SOD level
and lowest MDA level when human erythrocytes challenged with tertiary butyl hydroperoxide (tBHP)
were treated with the extract. This study confirms the retention of a considerable quantity of bioactive
constituents of plants when freeze-dried
Phenolic Extract from Moringa oleifera
This study was designed to determine the antioxidant properties and inhibitory effects of extract from Moringa oleifera leaves on angiotensin-I-converting enzyme (ACE) and arginase activities in vitro. The extract was prepared and phenolic (total phenols and flavonoid) contents, radical (nitric oxide (NO), hydroxyl (OH)) scavenging abilities, and Fe2+-chelating ability were assessed. Characterization of the phenolic constituents was done via high performance liquid chromatography-diode array detection (HPLC-DAD) analysis. Furthermore, the effects of the extract on Fe2+-induced MDA production in ratsâ penile tissue homogenate as well as its action on ACE and arginase activities were also determined. The extract scavenged NOâ, OHâ, chelated Fe2+, and inhibited MDA production in a dose-dependent pattern with IC50 values of 1.36, 0.52, and 0.38âmg/mL and 194.23â”g/mL, respectively. Gallic acid, chlorogenic acid, quercetin, and kaempferol were the most abundant phenolic compounds identified in the leaf extract. The extract also inhibited ACE and arginase activities in a dose-dependent pattern and their IC50 values were 303.03 and 159.59â”g/mL, respectively. The phenolic contents, inhibition of ACE, arginase, and Fe2+-induced MDA production, and radical (OHâ, NOâ) scavenging and Fe2+-chelating abilities could be some of the possible mechanisms by which M. oleifera leaves could be used in the treatment and/or management of erectile dysfunction
Phenolic bioactives as antiplatelet aggregation factors: the pivotal ingredients in maintaining cardiovascular health
Cardiovascular diseases (CVD) are one of the main causes of mortality in the world. The development of these diseases has a specific factorâalteration in blood platelet activation. It has been shown that phenolic compounds have antiplatelet aggregation abilities and a positive impact in the management of CVD, exerting prominent antioxidant, anti-inflammatory, antitumor, cardioprotective, antihyperglycemic, and antimicrobial effects. Thus, this review is intended to address the antiplatelet activity of phenolic compounds with special emphasis in preventing CVD, along with the mechanisms of action through which they are able to prevent and treat CVD. In vitro and in vivo studies have shown beneficial effects of phenolic compound-rich plant extracts and isolated compounds against CVD, despite that the scientific literature available on the antiplatelet aggregation ability of phenolic compounds in vivo is scarce. Thus, despite the current advances, further studies are needed to confirm the cardioprotective potential of phenolic compounds towards their use alone or in combination with conventional drugs for effective therapeutic interventions.N.C.-M. acknowledges the Portuguese Foundation for Science and Technology under the Horizon 2020 Program
(PTDC/PSI-GER/28076/2017).info:eu-repo/semantics/publishedVersio
Local salt substitutes âObu-otoyoâ activate acetylcholinesterase and butyrylcholinesterase and induce lipid peroxidation in rat brain
Interaction of Some Commercial Teas with Some Carbohydrate Metabolizing Enzymes Linked with Type-2 Diabetes: A Dietary Intervention in the Prevention of Type-2 Diabetes
This study is aimed at assessing the inhibitory effect of teas on key enzymes (α-amylase and α-glucosidase) linked with type-2 diabetes and their antioxidant properties. Four samples of three brands were used; infusions of green tea (GT), 2 brands of black tea (BT), and a formulated herbal preparation for diabetes (ADT) (white tea, Radix Puerariae, Radix ophiopogonis, hawthorn berry, Chinese yam, and fragrant Solomon seal rhizome) were prepared and subsequently analyzed for their total phenol, ascorbic acid contents, antioxidant properties (2,2-Azizobis
(3-Ethylbenzo-Thiazoline~6-sulfonate) âABTSâ scavenging ability and ferric reducing antioxidant property), and inhibition of pancreatic-α-amylase and intestinal-α-glucosidase in vitro. The study revealed that GT had the highest total phenol content, ascorbic acid content, ABTS* scavenging ability, and ferric reducing ability. Furthermore, all the teas inhibited Fe2+ and sodium nitroprusside induced lipid peroxidation in pancreas, with GT having the highest inhibitory effect. Conversely, there was no significant difference (P>0.05) in the inhibitory effects of the teas on α-amylase and α-glucosidase. The antidiabetic property of the teas could be attributed to their inhibitory effect on carbohydrate hydrolyzing enzymes implicated in diabetes and their antioxidant activities
Phenolic extracts and amino acids content from Cucumeropsis mannii naudin and Citrullus lanatus inhibit relevant enzymes of erectile dysfunction in rat's penile tissue
Inhibitory effect of polyphenolicârich extract from Cola nitida (Kolanut) seed on key enzyme linked to type 2 diabetes and Fe2+ induced lipid peroxidation in rat pancreas in vitro
Objective: To investigate the inhibitory effect of phenolic-rich extracts from Cola nitida (C. nitida) seeds on key enzymes linked with type-2 diabetes and Fe2+ induced oxidative stress in rat pancreas.
Methods: The phenolic extract was prepared with 80% acetone (v/v). Subsequently, the antioxidant properties and inhibitory effect of the extract on α â amylase and α â glucosidase as well as on Fe2+ induced lipid peroxidation in rat pancreas were determined in vitro.
Results: The result revealed that C. nitida extract inhibited α-amylase (EC50=0.34 mg/mL) and α-glucosidase (EC50=0.32 mg/mL) activities as well as Fe2+ induced lipid peroxidation in rat pancreas in a dose dependent manner. In addition, the extract had high DPPH radical scavenging ability (EC50=2.2 mg/mL) and reducing power (8.2 mg AAE/g). Characterization of the main phenolic compounds of the extract using gas chromatography analysis revealed catechin (6.6 mg/100 g), epicatechin (3.6 mg/100 g), apigenin (5.1 mg/100 g) and naringenin (3.6 mg/100 g) were the main compounds in the extract.
Conclusions: This antioxidant and enzyme inhibition could be some of the possible mechanism by which C. nitida is use in folklore for the management/treatment of type-2 diabetes. However, the enzyme inhibitory properties of the extract could be attributed to the presence of catechin, epicatechin, apigenin and naringenin