Antioxidant activity of β-lactoglobulin and its modified derivatives

Both native ss-lactoglobulin and its modified derivatives (Figure 1) exhibited antioxidant activity when assessed by the FRAP assay (which measures total reducing power of the sample). A positive correlation was observed between antioxidant activity and protein concentration in all samples. Compared to the native protein, the concentration dependence of the antioxidant activity was significantly greater when ss-lactoglobulin was modified with the Maillard reaction (p=0.000) and Enzyme hydrolysis (p=0.022)....

Correlation between acidic potassium permanganate chemiluminescence and in vitro cell culture assay : physiologically meaningful antioxidant activity

There is great interest in the activity of antioxidant molecules, including polyphenols, from food and plant sources. Acidic potassium permanganate chemiluminescence signal intensity was shown to predict the ability of polyphenols to positively act on cellular redox state and attenuate oxidative stress in cultured skeletal muscle cells.

Red wine consumption increases antioxidant status and decreases oxidative stress in the circulation of both young and old humans

Background: Red wine contains a naturally rich source of antioxidants, which may protect the body from oxidative stress, a determinant of age-related disease. The current study set out to determine the in vivo effects of moderate red wine consumption on antioxidant status and oxidative stress in the circulation.
Methods: 20 young (18–30 yrs) and 20 older (≥ 50 yrs) volunteers were recruited. Each age group was randomly divided into treatment subjects who consumed 400 mL/day of red wine for two weeks, or control subjects who abstained from alcohol for two weeks, after which they crossed over into the other group. Blood samples were collected before and after red wine consumption and were used for analysis of whole blood glutathione (GSH), plasma malondialdehyde (MDA) and serum total antioxidant status.
Results: Results from this study show consumption of red wine induced significant increases in plasma total antioxidant status (P < 0.03), and significant decreases in plasma MDA (P < 0.001) and GSH (P < 0.004) in young and old subjects. The results show that the consumption of 400 mL/day of red wine for two weeks, significantly increases antioxidant status and decreases oxidative stress in the circulation.
Conclusion: It may be implied from this data that red wine provides general oxidative protection and to lipid systems in circulation via the increase in antioxidant status.

Consumer acceptability and antioxidant potential of probiotic-yogurt with spices

The study focuses on developing novel probiotic yogurts containing spices with acceptable sensory properties, therapeutic levels of probiotics and with beneficial antioxidant capacity. Eight types of yogurts with added spice oleoresins (cardamom, cinnamon and nutmeg) and probiotics [Lactobacillus acidophilus strain 5(LA5), or Bifidobacterium animalisssp.Lactis (Bb12)] were produced. Two successive consumer sensory taste panels (n = 54) using a nine point hedonic scale were conducted to evaluate the acceptability of the yogurts. Viable counts of probiotics and antioxidant capacity of yogurt samples at 1, 7, 14 and 28 days of storage at 4 °C were monitored. The probiotic-yogurt products containing spices showed good sensory properties, with the best results obtained with cardamom oleoresin (with LA5 or Bb12). The presence of spice oleoresins (cardamom, nutmeg and cinnamon) did not affect the probiotic population (LA5or Bb12) in yogurt during 4 weeks of refrigerated storage. The antioxidant capacity (with LA5or Bb12) over the storage period was also maintained.

A novel in vitro whole plant system for analysis of polyphenolics and their antioxidant potential in cultivars of Ocimum basilicum

Plants are an important source for medicinal compounds. Chemical screening and selection is critical for identification of compounds of interest. Ocimum basilicum (Basil) is a rich source of polyphenolics and exhibits high diversity, therefore bioprospecting of a suitable cultivar is a necessity. This study reports on the development of a true to type novel "in vitro system" and its comparison with a conventional system for screening and selection of cultivars for high total phenolics, individual polyphenolics, and antioxidant content. We have shown for the first time using online acidic potassium permanganate chemiluminescence that extracts from Ocimum basilicum showed antioxidant potential. The current study identified the cultivar specific composition of polyphenolics and their antioxidant properties. Further, a distinct relationship between plant morphotype and polyphenolic content was also found. Of the 15 cultivars examined, "Holy Green", "Red Rubin", and "Basil Genovese" were identified as high polyphenolic producing cultivars while "Subja" was determined to be a low producer. The "in vitro system" enabled differentiation of the cultivars in their morphology, polyphenolic content, and antioxidant activity and is a cheap and efficient method for bioprospecting studies.

Acidic potassium permanganate chemiluminescence for the determination of antioxidant potential in three cultivars of Ocimum basilicum

Ocimum basilicum, a member of the family Lamiaceae, is a rich source of polyphenolics that have antioxidant properties. The present study describes the development and application of an online HPLC-coupled acidic potassium permanganate chemiluminescence assay for the qualitative and quantitative assessment of antioxidants in three cultivars of O. basilicum grown under greenhouse conditions. The chemiluminescence based assay was found to be a sensitive and efficient method for assessment of total and individual compound antioxidant potential. Leaves, flowers and roots were found to be rich reserves of the antioxidant compounds which showed intense chemiluminescence signals. The polyphenolics such as rosmarinic, chicoric, caffeic, p-coumaric, m-coumaric and ferulic acids showed antioxidant activity. Further, rosmarinic acid was found to be the major antioxidant component in water-ethanol extracts. The highest levels of rosmarinic acid was found in the leaves and roots of cultivars "holy green" (14.37; 11.52 mM/100 g DW respectively) followed by "red rubin" (10.02; 10.75 mM/100 g DW respectively) and "subja" (6.59; 4.97 mM/100 g DW respectively). The sensitivity, efficiency and ease of use of the chemiluminescence based assay should now be considered for its use as a primary method for the identification and quantification of antioxidants in plant extracts.

Comparison of antimicrobial activity, phytochemical profile and minerals composition of garlic Allium sativum and Allium tuberosum

Allium species are considered to be one of the world's oldest cultivated vegetables. Most commonly used species of garlic in Pakistan and India is Allium sativum, while Allium tuberosum is mainly consumed and cultivated in China, Southeast Asia, and North-east part of India. The present study was conducted to compare the antimicrobial activity, nutritional value and antioxidant profile of Allium sativum and Allium tuberosum. The outcome indicates that Allium tuberosum have slightly higher antimicrobial activity, higher mineral profile, and enriched in antioxidants in comparison with Allium sativum. The highest antimicrobial activity of Allium tuberosum was noticed against Staphylococcus aureus and Bacillus subtilis with 43.9 and 40.7 mm zone of inhibition using 100% extract. Allium tuberosum contains high contents of calcium (28.662±.00mg/100 g), potassium (10.62±0.50) and zinc (59.00±1.00). Allium tuberosum also showed higher antioxidant activity (0.24±0.03 mg vitamin C equivalent (VCE)/g fresh weight in ferric reducing antioxidant power assay, 0.18±0.02 mg VCE/g fresh weight in 2,2-diphenyl-1-picrylhydrazyl assay and 1.09±0.12 mg VCE/g fresh weight in 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) assay) in comparison with Allium sativum.

Effects of gamma-tocopherol supplementation on thrombotic risk factors

Objective: The antioxidant activity of vitamin E is derived primarily from alpha-tocopherol (α-T) and gammatocopherol (γ-T). Results of epidemiological studies have demonstrated an inverse relationship between vitamin E intake and coronary disease. However, the results of clinical trials using α-T are equivocal. We determined the effect of 5 weeks of 100 mg/d or 200 mg/d γ-T supplementation on thrombotic markers such as platelet reactivity, lipid profile and the inflammation marker C-reactive protein (CRP). Methods and results: Fourteen healthy subjects consumed 100 mg/day while 13 consumed 200 mg/d of γ-T and 12 received placebo (soybean capsules with less than 5 mg/d γ-T) in a double-blinded parallel study design. Fasting pre and post dose blood samples were analysed. Blood γ-T concentrations increased significantly (p<0.05) relative to dose during the intervention period. Both groups receiving active ingredients showed significantly lower platelet activation after supplementation (p<0.05). Subjects consuming 100 mg/d γ-T had significantly decreased LDL cholesterol, platelet aggregation and mean platelet volume (MPV) (p<0.05). Little effect of γ-T was observed on other parameters. Conclusions: These data suggest that γ-T  supplementation may have a permissive role in decreasing the risk of
thrombotic events by improving lipid profile and reducing platelet activity.

A simple 96-well microplate method for estimation of total polyphenolic content in seaweeds

Seaweed polyphenols are potent antioxidants and have also been shown to have α-glucosidase inhibiting activity. In our continuous efforts to develop new marine-based nutraceuticals and functional food ingredients, we have investigated many algal species collected on the Atlantic coast of Canada. A simple method for estimating the total polyphenol content in seaweeds and their extracts was developed based on the classic Folin-Ciocalteau colorimetric reaction. By using the 96-well microplate and a microplate reader, this new method saves experimental time, significantly reduces the amount of sample required, handles large number of samples in one experiment, and also improves the repeatability of the results.

A number of algal samples collected on the seashore of Nova Scotia, Canada, were analyzed for their levels of polyphenol content using this microplate-based method. The antioxidant activity of these samples was also assessed by using DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical scavenging assay. The results showed that there is a strong correlation between the total polyphenol content and the potency of antioxidant effect.

Survivin mutant protects differentiated dopaminergic SK-N-SH cells against oxidative stress

Oxidative stress is due to an imbalance of antioxidant/pro-oxidant homeostasis and is associated with the progression of several neurological diseases, including Parkinson’s and Alzheimer’s disease and amyotrophic lateral sclerosis. Furthermore, oxidative stress is responsible for the neuronal loss and dysfunction associated with disease pathogenesis. Survivin is a member of the inhibitors of the apoptosis (IAP) family of proteins, but its neuroprotective effects have not been studied. Here, we demonstrate that SurR9-C84A, a survivin mutant, has neuroprotective effects against H2O2-induced neurotoxicity. Our results show that H2O2 toxicity is associated with an increase in cell death, mitochondrial membrane depolarisation, and the expression of cyclin D1 and caspases 9 and 3. In addition, pre-treatment with SurR9-C84A reduces cell death by decreasing both the level of mitochondrial depolarisation and the expression of cyclin D1 and caspases 9 and 3. We further show that SurR9-C84A increases the antioxidant activity of GSH-peroxidase and catalase, and effectively counteracts oxidant activity following exposure to H2O2. These results suggest for the first time that SurR9-C84A is a promising treatment to protect neuronal cells against H2O2-induced neurotoxicity.