Scavenging Lipid Peroxidation Research Articles

Polystyrene nanoparticles induce concerted response of plant defense mechanisms in plant cells

Recent advances in knowledge suggest that micro- and nanoplastics pose a threat to plant health, however, the responses of plants to this stressor are not well-known. Here we examined the response of plant cell defence mechanisms to nanoparticles of commonly used plastic, polystyrene. We used plant cell cultures of widely cultivated plants, the monocots wheat and barley (Triticum aestivum L., Hordeum vulgare L.) and the dicots carrot and tomato (Daucus carota L., Solanum lycopersicum L.). We measured the activities of enzymes involved in the scavenging of reactive oxygen species and nonenzymatic antioxidants and we estimated potential damages in plant cell structures and functioning via lipid peroxidation and DNA methylation levels. Our results demonstrate that the mode of action of polystyrene nanoparticles on plant cells involves oxidative stress. However, the changes in plant defence mechanisms are dependent on plant species, exposure time and nanoplastic concentrations. In general, both monocots showed similar responses to nanoplastics, but the carrot followed more the response of monocots than a second dicot, a tomato. Higher H2O2, lipid peroxidation and lower enzyme activities scavenging H2O2 suggest that tomato cells may be more susceptible to polystyrene-induced stress. In conclusion, polystyrene nanoplastics induce oxidative stress and the response of the plant defense mechanisms involving several chain reactions leading to oxidoreductive homeostasis.

Neuroprotective Potential of Isoquinoline Alkaloids from Glaucium grandiflorum Boiss. and A. Huet subsp. refractum (Nábelek) Mory: Role of NRF2-KEAP1 Pathway

The extracts of Glaucium grandiflorum have been used to treat neurodegenerative diseases. Nonetheless, no former study has investigated whether the alkaloid extracts of G. grandiflorum have antioxidative effects against oxidative stress. The aim of the present study was to determine the antioxidative effects of the alkaloid extracts of G. grandiflorum with a variety of targets and probable mechanisms. First, we used spectrophotometry to investigate alkaloid extracts with respect to their alkaloid amounts. Then, we determined the alkaloid extracts’ impact on thiol/disulfide homeostasis, total oxidant status/total antioxidant status/oxidative stress index, and antioxidant enzyme activities. Finally, the effects of alkaloid extracts on the genes in the NRF2-KEAP1 pathway were determined via qRT-PCR. We conducted molecular docking analyses to determine the potential binding of isoquinoline alkaloids found within the alkaloid extracts with target proteins. We observed the best results from chloroform alkaloid extract and methanol alkaloid extract. Chloroform alkaloid extract was prominent in DPPH radical scavenging and metal ions chelating, and methanol alkaloid extract showed significant hydroxyl radical scavenging, lipid peroxidation, and superoxide anion radical scavenging activity. Alkaloid extract groups substantially increased in total thiol activity, native thiol activity, disulfide activity, total antioxidant status level, antioxidant enzyme levels, and gene expression levels (GCLC, HO-1, NRF2, and NQO1) compared to the H2O2 group. Also, alkaloid extract groups led to a significant drop in total oxidant status level, oxidative stress index level, and KEAP1 gene expression level relative to the H2O2 group. According to our study results, oxidative stress brought about by H2O2 was regulated by alkaloid extracts. As a result, a phytochemical-based therapeutic that regulates H2O2-induced oxidative stress was brought to the neurochemical field.

Regulation of iron metabolism and ferroptosis in cancer stem cells.

The ability of cancer stem cells (CSCs) to self-renew, differentiate, and generate new tumors is a significant contributor to drug resistance, relapse, and metastasis. Therefore, the targeting of CSCs for treatment is particularly important. Recent studies have demonstrated that CSCs are more susceptible to ferroptosis than non-CSCs, indicating that this could be an effective strategy for treating tumors. Ferroptosis is a type of programmed cell death that results from the accumulation of lipid peroxides caused by intracellular iron-mediated processes. CSCs exhibit different molecular characteristics related to iron and lipid metabolism. This study reviews the alterations in iron metabolism, lipid peroxidation, and lipid peroxide scavenging in CSCs, their impact on ferroptosis, and the regulatory mechanisms underlying iron metabolism and ferroptosis. Potential treatment strategies and novel compounds targeting CSC by inducing ferroptosis are also discussed.

In Vitro Antioxidant, Anti-inflammatory, Antimicrobial, and Antidiabetic Activities of Synthesized Chitosan-loaded p-Coumaric Acid Nanoparticles.

p-Coumaric acid is a phenolic compound widely distributed in fruits and vegetables that displays an array of therapeutic properties, including antidiabetic effects. Prominent application in diabetes is limited due to its suboptimal pharmacokinetics, poor aqueous solubility, and poor bioavailability. Nanotechnology-based delivery methods have been developed to address these limitations and improve the therapeutic uses of p-coumaric acid, and the nanoencapsulation method is emerging as a feasible alternative. The objective of this study is to synthesize p-coumaric acid nanoparticles (PCNPs) and to evaluate their In Vitro activities. The PCNPs were synthesized by the nanoprecipitation method and characterized by UV-visible spectroscopy, zeta potential, Fourier-transform infrared (FTIR) spectroscopy, and scanning electron microscopy (SEM) with dispersive energy X-ray (EDX) analysis. In addition, the PCNPs were analyzed for In Vitro antioxidant activity using six different free radical scavenging assays and were also analyzed for antimicrobial, anti-inflammatory, antithrombotic, and antidiabetic effects. The formation of PCNPs was confirmed by UV-visible spectra at 283 nm, and FTIR analysis revealed the reduction and capping of the chitosan nanoparticles. SEM was used to assess the size and shape of the PCNPs, and the high absorption property of the PCNPs was investigated using EDX analysis. The PCNPs had significant antioxidant, hydrogen peroxide (H2O2), lipid peroxidation (LPO), superoxide and nitric oxide (NO) radical scavenging power activities, and showed potent antimicrobial, anti-inflammatory, antithrombotic, and antidiabetic activities. The present study suggests that PCNPs can be used as a potential medication delivery approach to provide a greater nephroprotective effect in the treatment of diabetic nephropathy. To the best of our knowledge, this is the first attempt at the synthesis of chitosan-loaded PCNPs.

Chemoprofiling and In vitro antioxidant potentials of methanol water extracts from Nigerian ginger (Zingiber officinale)

Ginger (Zingiber officinale) is one of the popular spices in Nigeria. It is highly utilised over the world as spice as well as for the treatment of inflammation, arthritis and other conditions involving reactive oxygen species (ROS), which are known to damage human cells. The proximate, phytochemical composition and antioxidant properties of the plant are reported in this work. Extraction by maceration was used for the pulverized rhizomes with methanol-water (50:50). Further partitioning of the extract was carried out using n-hexane, ethyl acetate and butanol into different fractions according to their polarity. The antioxidant activity was evaluated with 1,1-diphenyl-2-icrylhydrazyl (DPPH) radical scavenging assay, ferric reducing antioxidant power (FRAP) assay, nitric oxide radical scavenging activity (NOSA) and lipid peroxidation scavenging activity (LPSA). The proximate content was determined using conventional chemical methods. The FTIR analyses of n-hexane fraction of Z. officinale revealed some functional groups that may be present in two likely classes of secondary metabolites: terpenes and alkaloids. The ethyl acetate fraction produced flavonoid (121.31 mg/100 g; quercetin) and alkaloids because of the functional groups associated with them, while the butanol fraction with functional groups present revealed cardiac glycosides (4.88 mg/100 g; digoxin) and alkaloids (45.19 mg/100 g). The plant also contained reducing sugar (64.62 mg/100 g glucose), steroids (8.65 mg/100 g; cholesterol), tannins (56.82 mg/100 g; tannic acid) and phenolic compounds (110.64 mg/100 g; gallic acid) from the phytochemical analyses. The proximate analysis revealed that it has a high carbohydrate content (54.54%), but a relatively modest crude fibre (10.21%), moisture content (10.02%), total ash (9.30%), crude fat (8.80%) and crude protein (7.12%). The presence of these phyto-compounds could explain its customary use as oxidative stress inhibitor.

In-Vitro Lipid Peroxidation and Free Radical Scavenging Activity of Eight Different Polyherbal Formulation Drugs

In-Vitro Lipid Peroxidation and Free Radical Scavenging Activity of Eight Different Polyherbal Formulation Drugs

Deuterated polyunsaturated fatty acids provided protection against oxidative stress in ocular fibroblasts derived from glaucoma patients

Glaucoma is a complex neurodegenerative disease of the optic nerve that leads to irreversible sight loss. Lowering intraocular pressure (IOP) medically or surgically represents the mainstay of treatment but despite adequate treatment optic nerve function can continue to deteriorate leading to blindness. There is significant clinical and experimental evidence that oxidative stress is involved in the pathogenesis of glaucoma. Decreasing the formation of lipid peroxidation products or scavenging them chemically could be beneficial in limiting the deleterious effects of oxidative stress in glaucoma. A solution to control the susceptibility of PUFAs to noxious lipid peroxidation reactions is by regioselective deuteration. Deuterium incorporated into PUFAs at bis-allylic positions (D-PUFAs) inhibits the rate-limiting step of lipid peroxidation. In this study, we have shown that Tenon’s ocular fibroblasts from glaucoma patients have significantly increased basal oxidative stress compared to non-glaucomatous control patients. Furthermore, we have shown that deuterated polyunsaturated fatty acids (D-PUFAs) provide an enhanced rescue of menadione induced lipid peroxidation in both non-glaucomatous and glaucomatous Tenon’s ocular fibroblasts using malondialdehyde (MDA) levels as a marker. Our study suggests that D-PUFAs may provide a potentially safe and effective method to reduce cytotoxic oxidative stress in glaucoma.

Correlation between oxidative stress markers and cytokines in different stages of breast cancer.

This study aims to estimate the level of malondialdehyde (MDA) as oxidative stress marker and reduced glutathione (GSH) as antioxidant and correlate them to different inflammatory markers as interleukins (IL-6, IL-8, IL-10) and tumor necrosis factor alpha (TNF-α) in different stages of breast cancer (BC). For the purpose of comparisons, 35 healthy subjects matched for age, sex and ethnic background were selected who have no history or clinical evidence of BC or any chronic disease and obvious abnormalities as a control group and 35 patients of different stages of BC were participated in the study. The cancer patients were diagnosed by specialists. Even the exact cause of the disease has not been identified but according to this study, 5% of the patients were having family history of the disease and 62% of the patients were having a BMI over 25. Over 60% of the patients were postmenopausal and all females participated in this study were nonsmokers. MDA level showed a significant increase when BC patients were compared to healthy subjects, this oxidative stress marker showed a significant increase with the increase of the stage of the disease. In contrast the level of the lipid peroxide scavenger GSH reduced with increasing the stage of the disease. The level of some cytokines showed a significant change between different stages and the control group. Correlation between MDA and GSH with these cytokines showed a positive correlation between all cytokines and the MDA level and a negative correlation between GSH and the cytokines. The results of this study suggests that BC stimulates the oxidative stress response and for that, different inflammatory cytokines will be produced and there is a pronounced relationship between oxidative stress parameters and these cytokines and the level of these cytokines are associated with aggressive tumors.

Antioxidant and Hepatoprotective Activity of Leaf Extract of Smilax Anceps Wild

Introduction: Smilax anceps leaf is used for general healing of the body in traditional medicine. The aim of this study was to investigate the in-vitro antioxidant potential and in-vivo hepatoprotective activity of the ethanol leaf extract of Smilax anceps against carbon tetrachloride induced hepatotoxicity. Materials and Methods: Preliminary phytochemical screening and acute toxicity were determined. In-vitro antioxidant activity of the plant was evaluated using 2, 2-diphenyl-1-picryl-hydrazyl (DPPH), reducing power activity, nitric oxide scavenging, and lipid peroxidation scavenging activity assays. In- vivo hepatoprotective activity was determined using albino rats, divided into groups of six comprising of 5 animals each vis the control, CCl4, extract 250,500 and 1000mg/kg, and silymarin 100mg/kg. Treatments were done for seven days and carbon tetrachloride dissolved in olive oil was administered on the seventh day. Biochemical analysis was performed to assay the levels of aspartate aminotransferase (AST), alanine amino transaminase (ALT), alkaline phosphatase (ALP), albumin (ALB), total protein (TP) and Total bilirubin (TB) with histological examination of the liver. Phytochemical screening showed the presence of saponins, flavonoids, tannins, carbohydrates and steroids/ terpenoids. Results: The extract showed significant (P<0.01) scavenging activity against DPPH, reducing power activity, nitric oxide scavenging, and lipid peroxidation. There was a statistically significant (P<0.05) decrease in total bilirubin (TB), alanine amino transaminase (ALT) and alkaline phosphatase (ALP). Conclusion: The findings of this study showed that the ethanol leaf extract of S. anceps possesses significant antioxidant and hepatoprotective which might be due to the presence of flavonoids.

Phosphorylated chitosan accelerates dermal wound healing in diabetic wistar rats

Phosphorylated chitosan (PC), a water-soluble derivative of chitosan possesses several biological and chemical properties suitable for diabetic wound healing. In the present study, we report the synthesis and diabetic wound healing capabilities of PC. Elemental analysis, FT-IR, 13C-NMR and 31P-NMR techniques were employed for the chemical characterization of PC. In vitro, antioxidant properties of PC were determined in terms of Fe3+ reducing, metal chelating, lipid peroxidation and superoxide scavenging ability. The wound healing potential of PC was assessed in diabetic excisional wound rat model. PC exhibited good water solubility, and in vitro antioxidant capacity. Wound contraction was higher in PC-treated wounds (91.11%) as compared to untreated wounds (67.26%) on 14th-day post wound creation. Histopathology of PC-treated wounds revealed improved tissue morphology with higher number of fibroblasts, a thicker epithelial layer, enhanced collagen deposits and angiogenesis as compared to untreated wounds. An overall increase of 57% and 25% in hydroxylamine and hexosamine content respectively were noted as compared to untreated wounds. A significant (P ≤ 0.05) increase in SOD activity and a significant (P ≤ 0.05) decrease in lipid peroxides were recorded in PC-treated wounds as compared to untreated wounds. These observations demonstrated that PC can be used as an effective agent in diabetic wound healing.Graphical Illustration of phosphorylated chitosan (PC) synthesis and its wound healing potential: Chitosan was phosphorylated to impart diabetic wound healing properties. Chemical characterizations such as elemental analysis, FT-IR and NMR confirmed successful phosphorylation of chitosan. PC exhibited good in vitro antioxidant properties. To assess the diabetic wound healing potential, an excisional wound model was developed in diabetic rats. PC treatment demonstrated accelerated wound healing.

The Possible Connection of Two Dual Function Processes: The Relationship of Ferroptosis and the JNK Pathway.

Ferroptosis represents a typical process that has dual functions in cell fate decisions since the reduction and/or inhibition of ferroptosis is desirable for the therapies of diseases such as neurological disorders, localized ischemia-reperfusion, kidney injury, and hematological diseases, while the enhanced ferroptosis of cancer cells may benefit patients with cancer. The JNK pathway also has a real dual function in the fate of cells. Multiple factors suggest a potential link between the ferroptotic and JNK pathways; (i) both processes are ROS mediated; (ii) both can be inhibited by lipid peroxide scavengers; (iii) RAS mutations may play a role in the initiation of both pathways. We aimed to investigate the possible link between ferroptosis and the JNK pathway. Interestingly, JNK inhibitor co-treatment could enhance the cancer cytotoxic effect of the ferroptosis inducers in NRAS and KRAS mutation-harboring cells (HT-1080 and MIA PaCa-2). Since cancer’s cytotoxic effect from the JNK inhibitors could only be suspended by the ferroptosis inhibitors, and that sole JNK-inhibitor treatment did not affect cell viability, it seems that the JNK inhibitors “just” amplify the effect of the ferroptosis inducers. This cancer cell death amplifying effect of the JNK inhibitors could not be observed in other oxidative stress-driven cell deaths. Hence, it seems it is specific to ferroptosis. Finally, our results suggest that GSH content/depletion could be an important candidate for switching the anti-cancer effect of JNK inhibitors.

Ketoprofen lysine salt has a better gastrointestinal and renal tolerability than ketoprofen acid: A comparative tolerability study in the Beagle dog

Due to the widespread use of non-steroidal anti-inflammatory drugs (NSAIDs), the incidence of NSAID-associated adverse events has increased exponentially over the past decades. Ketoprofen (ketoprofen acid, KA) is a widely used NSAID and, like with other NSAIDs, its use can be associated with adverse effects that especially involve the gastrointestinal tract and the kidney. The salification of KA with L-lysine has led to the synthesis of ketoprofen lysine salt (KLS), which is characterized by higher solubility and a more rapid gastrointestinal absorption compared to KA. Previous studies have reported that KLS has also an increased gastric tolerance in vitro, and this is due to the inhibition of lipid peroxidation and reactive oxygen species scavenging effects of L-lysine. Here, we report in vivo tolerability/toxicity studies that were conducted prior seeking KLS marketing authorization, in which we compared KLS and KA safety profile, focusing in particular on the evaluation of the gastrointestinal and renal tolerability of the drugs administered orally to dogs. Our results demonstrate that KLS has an increased in vivo gastrointestinal tolerability compared to KA and show, for the first time, that KLS has also increased in vivo renal tolerability compared to KA, thus supporting the concept that L-lysine may counteract NSAID-induced oxidative stress-mediated gastrointestinal and renal injury.

Comprehensive study of chemical composition and biological activity of Thymus pubescens Boiss. et Kotschy ex Čelak.

The use of Thymus species amongst the public and their importance in the scientific world is increasing day by day. In addition to being consumed as tea and spice, Thymus species are used as folk medicine for respiratory, digestive, skin, circulatory, genital, nervous, visual and urinary diseases. In this study, it was aimed to examine the essential oil and ethanol extract of the root and aerial parts of Thymus pubescens Boiss. et Kotschy ex Celak in the terms of their biological activity and chemical content. The phenolic content of the species was determined by LC-MS/MS, while triterpenoid content, the chemical composition of the essential oil as well as flavour was determined by GC–MS. In addition, their antioxidant and cytotoxic activities, as well as acetyl- (AChE) and butyrylcholinesterase (BChE), urease, tyrosinase, elastase, collagenase, HMG-CoA reductase and angiotensin-converting enzyme (ACE) inhibitory activities were studied. Thymol (53.33%) was determined as the major component in the essential oil, while β-fenchyl alcohol (43.87%) was determined as the major component of the flavour. According to the LC-MS/MS and GC–MS results, it was found that especially the aerial parts of the species have a high amount of rosmarinic acid (3875.76 µg analyte/g extract), quinic acid (2392.55), naringenin (970.39), oleanolic (92785.96) and ursolic (63373.32) acids. The essential oil of T. pubescens species was observed to show high activity in four antioxidant assays, e.g. inhibition of lipid peroxidation, DPPH and ABTS radical scavenging activity as well as CUPRAC, while the ethanol extracts showed moderate antioxidant activity. In enzyme inhibition assays, the aerial parts exerted marked BChE, elastase, and collagenase inhibitory activities (92.43±1.28%, 42.59±0.56, and 48.61±0.39 at 100 µg/mL, respectively). On the other hand, AChE, urease, tyrosinase, HMG-CoA reductase and ACE inhibitory activities of all extracts were from low to moderate levels. In particular, the aerial parts of the species displayed a high cytotoxic effect (vitality%: 6.82±0.01 at 200 µg/mL) in breast cancer (MCF-7) cell line. Due to its remarkable antioxidant capacity, high content of rosmarinic, oleanolic, and ursolic acids and especially BChE, elastase, and collagenase inhibitory activity, T. pubescens has the potential for using in food supplements, food preservatives, cosmetics, and pharmaceutical industries.

Inhibition of lipid peroxidation and free radical scavenging activities of methanolic leaf extract of Psidium guajava

Objectives: Studies have linked the generation of free radicals with the incidence of degenerative diseases. Antioxidants from plant origin have been proved to play a major role in mitigating against free radicals-induced oxidative damage. This study aimed at assessing the in-vitro and in-vivo antioxidant capability of Psidium guajava leafMethods: The leaves were collected and extracted with 70% methanol. Total phenolic, and flavonoids contents, 2,2-diphenyl-1-picrylhydrazyl and Hydroxyl radicals scavenging activities, and inhibition of lipid peroxidation potential of the extract were assessed. Furthermore, rats (n=21) randomized into three groups were exposed to 50, 150, and 250 mg/kg body weight of the extract for 30 days. Control animals (n=7) received corn oil, after which blood and liver were excised for antioxidant assay.Results: The extract is rich in phenolic and flavonoid compounds. It scavenged DPPH and hydroxyl radicals and inhibits lipid peroxidation in-vitro. In-vivo, it increased the activities of hepatic superoxide dismutase, catalase, glutathione peroxidase, and plasma paraoxonase, and the concentration of hepatic reduced glutathione and MDA.Conclusion: Psidium guajava leaf extract is a potential source of natural antioxidant compounds, capable of supplementing the body's antioxidant defense system.

Assessment of In vitro Antioxidant Potential of the Polyphenols and the Sulphated Polysaccharides fractions of Ulva lactuca and Turbinaria ornata

Aims: To assess the in vitro antioxidant potential of the polyphenols and the sulphated polysaccharides fractions from green marine alga Ulva lactuca and brown marine alga Turbinaria ornata.
 Study Design: In the present work, 1,1-diphenyl-2-picryl-hydrazyl (DPPH), lipid peroxidation, hydroxyl radical and hydrogen peroxide scavenging activities were used for the evaluation of the antioxidant potential of the polyphenols and the sulphated polysaccharides fractions from Ulva lactuca and Turbinaria ornata.
 Place and Duration of Study: Department of Biochemistry, Adhiparasakthi College of Arts and Science (Autonomous), G.B. Nagar, Kalavai – 632 506, Tamil Nadu, India.
 Methodology: The polyphenols and the sulphated polysaccharides fractions were extracted from green marine alga Ulva lactuca and brown marine alga Turbinaria ornata, and were assayed for in vitro antioxidant potential using the 1,1-diphenyl-2-picryl-hydrazyl (DPPH), lipid peroxidation, hydroxyl raidcal and hydrogen peroxide scavenging activities.
 Results: Both the polyphenols and the sulphated polysaccharides fractions were extracted from green marine alga Ulva lactuca and brown marine alga Turbinaria ornata, showed good in vitro antioxidant potential with the 1,1-diphenyl-2-picryl-hydrazyl (DPPH), lipid peroxidation, hydroxyl radical and hydrogen peroxide scavenging activities. The percentage of inhibition ranged from 90.37 – 100.0 % inhibition for polyphenols fraction and 68.73 – 95.23 % for sulphated polysaccharides. The IC50 values ranged from 0.185 mg/ml to 0.430 mg/ml.
 Conclusion: Both the polyphenols and the sulphated polysaccharides fractions from Ulva lactuca and Turbinaria ornata are shown to be capable of scavenging a wide range of synthetic and naturally occurring free radicals, and they could be utilized as good natural source of antioxidants. These data may contribute to a rational basis for the use of antioxidant-rich marine algal fractions in the therapy of diseases related to oxidative stress.

Antioxidant Properties and In-Vitro Radical Scavenging Activities of Tannin-Rich and Flavonoid-Rich Fraction of Annona senegelensis and Vernonia amygdalina leaves

Medicinal Plants have demonstrated history of managing some ailments caused by free radicals as a result of some chemical constituents they possess. This study was aimed at assessing antioxidant and free radical scavenging properties of Tannin-rich and Flavoniod-rich fraction of Annona senegelensis and Vernonia amygdalina leaves via in vitro assays such as; reducing power, nitric oxide scavenging activity, Hydrogen peroxide scavenging activity and Lipid peroxidation scavenging activity. The results obtained indicated that both medicinal plants are antioxidant reservoir. The values for Tannin rich fraction of Annona senegelensis (TRFAS) and Tannin rich fraction of Vernonia amygdalina (TRFVA) are Reducing power absorbance TRFAS (0.077-0.187), TRFVA (0.168-0239). % Nitric oxide scavenging: TRFAS (4.46-30.40), TRFVA (5.23-42.24). % H2O2 scavenging: TRFAS (7.30-20.35), TRFVA (8.12-22.32). % Lipid Perioxidation: TRFAS (6.81-32.76), TRFVA (5.16-26.16). Also the values for Flavonoid rich fraction of Annona senegelensis (FRFAS) and Flavonoid rich fraction of Vernonia amygdalina (FRFVA) are reducing power absorbance: FRFAS (0.109-0.342), FRFVA (0.124-0.388). % Nitric oxide scavenging: FRFAS (33.55-43.57), FRFVA (21.10-47.46). % H2O2 scavenging: FRFAS (39.01-74.96), FRFVA (45.80-75.20). % Lipid Perioxidation: FRFAS (24.81-59.69), FRFVA (41.43-59.98). The Tannin-rich and Flavonoid-rich fraction of both plants exhibited good antioxidant activity on all models employed at increasing concentrations but Flavoniod-rich fraction of Vernonia amygdalina had the highest inhibitory effect than the Tannin fraction. The findings from this study validated the pharmacological potency of the two plants and their potential use in combating free radical-related diseases, which are often triggered by oxidative stress.

METHANOL LEAF EXTRACT OF Jatropha tanjorensis Ellis and Saroja POSSESS PHYTOCONSTITUENTS WITH FREE RADICAL SCAVENGING ACTIVITY

The body during normal metabolic function produces free radicals which are highly reactive species. Free radicals could also be introduced into the body from the environment. The oxidation induced by reactive oxygen species can result in DNA mutation, membrane protein damage and cell membrane disintegration. The present study assayed the preliminary phytochemicals, total phenolics and total flavonoids and free radicals scavenging ability of methanol extract of Jatropha tanjorensis leaf. Standard methods for determining phytochemicals, reducing power, nitric oxide scavenging, hydroxyl radical, and lipid peroxidation scavenging activity were employed. The phytochemical screening result revealed the presences of phenols, flavonoids, saponin, alkaloids, tannins, terpernoids and steroids. The total phenolic content of methanol extract of Jatropha tanjorensis leaf measured by Folin-Ciocalteau reagent in terms of gallic acid equivalent was 11.35±0.82mgGAE/g. The flavonoid content of the plant sample calculated as Quercetin equivalent was 15.91±1.60mgQCE/g. GC-MS results revealed relevant pharmacological bioactive compounds. The antioxidative activity of the plant’s extract correlated with total phenolic content. The radical scavenging activity showed a dose dependent increase in the reducing power. The minimum NO inhibitory activity was 8.88±0.63 at 200µg/ml and the maximum activity was 32.70±2.71 at 800µg/ml. The minimum percentage H2O2 radical inhibitory activity was 8.30±0.88 at 200µg/ml and a maximum activity was 22.80±2.28 at 800µg/ml. There was also an increase scavenging effect of lipid peroxide radical in concentration dependent manner. The results of this study indicate that the leaf of Jatropha tanjorensis possess antioxidant properties and could serve as free radical inhibitor

The antioxidative-activity stability of aloe vera (Aloe vera var. chinensis) instant during storage

Aloe vera contains a phenolic compound that has bioactive activity. Previous research showed that microencapsulation of aloe vera powder with maltodextrin as an encapsulation agent produced instant aloe vera with high antioxidative activity. The problem was the hygroscopic instant caused rapid moisture and oxygen absorption during storage, therefore decreasing the instant aloe vera antioxidative activity periodically. The aim of this research was to evaluate the antioxidative activity stability of instant aloe vera during storage. The processing of instant aloe vera through a reconstituted aloe vera powder with water with a ratio of 1:120 and then added with 2.5% maltodextrin as the encapsulating agent. The solution was then inserted into a spray dryer with an inlet temperature of 130oC, an outlet temperature of 103oC, and the flow rate of the solution is 350.0 mL/h. The resulted instant aloe vera was divided into 15 packs with a weight of 25 g, and each sample was wrapped with polyethylene plastic film with 0.80 mm thickness and then was stored at 25oC with a relative humidity of 75%. The sample was conducted in triplicate. The moisture content, and antioxidative activity that was based on the ability to capture 1,1-diphenyl-2- picrylhydrazyl (DPPH) radical (RSA) and lipid peroxidation inhibition were analyzed every week until the critical condition was achieved at a moisture level of 12%. The research showed that the radical scavenging activity (RSA) and lipid peroxidation inhibition of instant aloe vera before storage were 16.34±1.22% and 39.33±1.68%, respectively, whereas in the critical condition the RSA was 3.63±0.04% and the lipid peroxidation inhibition was 22.31±0.02%. Based on their antioxidative activity, the appropriate storage time of instant aloe vera was about 12 weeks in polyethylene plastic film of 0.08 mm thickness

Fig seed oil‐loaded nanostructured lipid carriers: Evaluation of the protective effects against oxidation

The aim of this study was to develop a carrier system that protects fig seed oil (FSO) from oxidation by encapsulating into nanostructured lipid carriers (NLCs). NLCs were prepared by high shear mixing technique and the effects of solid lipids and surfactants on the formulation parameters were investigated. The formulations were characterized in terms of particle size, polydispersity index, and zeta potential, and fatty acid and tocopherol amounts were determined by GC and HPLC, respectively. NLC loaded with FSO was obtained at a particle size of 241 nm with low polydispersity (0.259) and a negative electrical charge (−13.6 mV). The antioxidant capacity has been evaluated by accelerated oxidation storage tests, radical and hydrogen peroxide scavenging activity tests. The stability of the final formulation with high concentration of gamma tocopherol and unsaturated linoleic acid content of FSO was increased by loading into NLCs. Novelty impact statement NLC formulations loaded with FSO were prepared for the first time at a dimension of 241 nm with low polydispersity. FSO was protected against lipid oxidation by encapsulation into NLC as revealed by lipid peroxidation, hydrogen peroxide, and radical scavenging activity tests. FSO-loaded NLC formulations were shown to be valuable carriers for encapsulation of bioactive food materials for stability.

Genetic variation in high light responses of Theobroma cacao L. accessions

Cacao (Theobroma cacao L.) is a shade-tolerant tree species, but in recent years it has increasingly been cultivated under full sun conditions in an orchard system where photoinhibition is likely. Here we investigate the extent of photoinhibition in 17 cacao accessions from a range of genetic groups, growing under high light conditions. The ability of the photosynthetic systems to respond to high light was assessed using chlorophyll fluorescence parameters (diurnal Fv/Fm and instantaneous light response curves), and differences in photosynthetic pigment content were compared using biochemical assays. Damage due to photoinhibition was assessed using electrolyte leakage, lipid peroxidation, and reactive oxygen species scavenging systems were compared using biochemical assays (for APX, CAT and SOD). There was significant variation between the 17 accessions for photosynthetic parameters, although in all cases the light saturation points were well below the midday light levels. Light acclimation of photosynthetic pigments was evident and variation in the total chlorophyll to total carotenoid ratio was significantly correlated with electrolyte leakage. Significant genetic variation was observed across the 17 accessions in the activities of CAT, APX and SOD. Across all accessions, photoprotection appeared to be restricted by the ability of leaves to generate SOD. Significant negative correlations were observed between SOD activity and both APX activity and electrolyte leakage, while significant positive correlations were observed between electrolyte leakage and both APX and CAT activity. Accessions with higher light saturation points, as well as high carotenoid and high SOD concentrations were able to tolerate the moderately high light, however, none of the accessions were clearly superior to the commonly grown Amelonado accession. The results imply that screening for SOD activity, total carotenoid content and light saturation point can aid in selection of genotypes with better tolerance to high light.