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Probiotic lactic acid bacteria (LAB) are a particular group of gram-positive bacteria that are usually involved in natural ferments and widely used in food manufacture industry. Most of them can produce exopolysaccharides (EPS), surface carbohydrate polymers with diverse biological functions. LAB EPS are potentially complementary and alternative medicines against cancer. EPS show anti-proliferative effects on a variety of tumor cells from intestine, liver, breast, etc. They modulate the development of tumors through various mechanisms including promoting apoptosis, inducing cell cycle arrest as well as anti-mutagenic, anti-oxidative, anti-angiogenesis and anti-inflammatory effects. Bacterial origin, existence form, chemical structure, purity et al. are important factors affecting the anticancer effects of EPS. The future challenge lies in elucidating the precise structure-function relationship of LAB EPS. Besides, more in vivo studies and further clinical trials are indispensable to confirm the anticancer effects., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Purple sweet potato anthocyanins are kinds of natural anthocyanin red pigments extracted from the root or stem of purple sweet potato. They are stable and have the functions of anti-oxidation, anti-mutation, anti-tumor, liver protection, hypoglycemia, and anti-inflammation, which confer them a good application prospect. Nevertheless, there is not a comprehensive review of purple sweet potato anthocyanins so far. The extraction, structural characterization, stability, functional activity, application in the food, cosmetics, medicine, and other industries of anthocyanins from purple sweet potato, together with their biotransformation in vitro or by gut microorganism are reviewed in this paper, which provides a reference for further development and utilization of anthocyanins.

As mutation causes many life-threatening diseases including cancer, a diet enriched with specific vegetables having potential to reduce mutagenesis possesses immense significance. In this study, 41 commonly used vegetables from diverse botanical taxa were evaluated and compared for their relative antimutagenic potential using standard assays [Escherichia coli RNA polymerase β (rpoB)-based Rif(S) → Rif(R) assay and Ames test] against known mutagens (UV, gamma radiation, 4-nitroquinoline-N-oxide and ethylmethanesulphonate). Significant differences in antimutagenicity were observed even among the cultivars within the same species, as well as at other phylogenetic levels such as genus or family. The effect of cooking in terms of boiling (aquathermal treatment), on the antimutagenicity of these vegetables, was also investigated. In majority of the cases, aquathermal treatment did not affect the antimutagenic potential. The antimutagenicity of these vegetables was not found to correlate well with their antioxidant properties.

In this study, we evaluated the effects of whey protein on oxidative stress in rats that were subjected to oxidative stress induced by iron overload. Thirty male rats were assigned to 3 groups: the control group (regular [50 mg/kg diet] dose of iron+20% casein), iron overload group (high [2,000 mg/kg] dose of iron+20% casein, IO), and whey protein group (high dose of iron+10% casein+10% whey protein, IO+whey). After 6 wk, the IO group showed a reduction in the plasma total radical trapping antioxidant parameter and the activity of erythrocyte superoxide dismutase and an increase in lipid peroxidation (determined from the proportion of conjugated dienes). However, whey protein ameliorated the oxidative changes induced by iron overload. The concentration of erythrocyte glutathione was significantly higher in the IO+whey group than in the IO group. In addition, whey protein supplementation fully inhibited iron overload-induced DNA damage in leukocytes and colonocytes. A highly significant positive correlation was observed between plasma iron levels and DNA damage in leukocytes and colonocytes. These results show the antioxidative and antigenotoxic effects of whey protein in an in vivo model of iron overload-induced oxidative stress.

Background: In this report, the isorhamnetin 3-o-robinobioside and its original extract, the ethyl acetate extract, from Nitraria retusa leaves, were evaluated for their ability to induce antioxidant and antigenotoxic effects in human chronic myelogenous leukemia cell line., Methods: Nitraria retusa products properties were carried out by firstly evaluating their effects against lipid peroxidation induced by H2O2, using the thiobarbituric acid reactive substances species (TBARS) assay, and proceeding to the assay of cellular antioxidant activity, then doing the comet assay., Results: The isorhamnetin 3-o-robinobioside showed a protective effect against lipid peroxidation induced by H2O2. The same natural compound and ethyl acetate extract inhibited oxidation induced by 2,2'-azobis (2-amidinopropane) dihydrochloride in human chronic myelogenous leukemia cells with respectively 50% inhibitory concentration values of 0.225 mg/ml and 0.31 mg/ml, reflecting a significant antioxidant potential. The same two products inhibited the genotoxicity induced by hydroxyl radicals in the same human cell line (by 77.77% at a concentration of 800 μg/ml and by 80.55% at a concentration of 1000 μg/ml respectively)., Conclusions: The isorhamnetin 3- o-robinobioside and its original extract, the ethyl acetate extract, from Nitraria retusa leaves, have a great antioxidant and antigenotoxic potential on human chronic myelogenous leukemia cell line K562.

Ilex paraguariensis dried and minced leaves are made into a brewed tea, prepared in a sui generis manner by large populations in South America, having evolved from a tea drunk by the Guarani ethnic group to a beverage that has a social and almost ritualistic role in some South American modern societies. It is used both as a source of caffeine, in lieu or in parallel with tea and coffee, but also as a therapeutic agent for its alleged pharmacological properties. Although with some exceptions, research on biomedical properties of this herb has had a late start and strongly lags behind the impressive amount of literature on green tea and coffee. However, in the past 15 years, there was a several-fold increase in the literature studying Ilex paraguariensis properties showing effects such as antioxidant properties in chemical models and ex vivo lipoprotein studies, vaso-dilating and lipid reduction properties, antimutagenic effects, controversial association with oropharyngeal cancer, anti-glycation effects and weight reduction properties. Lately, promising results from human intervention studies have surfaced and the literature offers several developments on this area. The aim of this review is to provide a concise summary of the research published in the past three years, with an emphasis on translational studies, inflammation and lipid metabolism. Ilex paraguariensis reduces LDL-cholesterol levels in humans with Ilex paraguariensis dyslipoproteinemia and the effect is synergic with that of statins. Plasma antioxidant capacity as well as expression of antioxidant enzymes is positively modulated by intervention with Ilex paraguariensis in human cohorts. A review on the evidence implicating Ilex paraguariensis heavy consumption with some neoplasias show data that are inconclusive but indicate that contamination with alkylating agents during the drying process of the leaves should be avoided. On the other hand, several new studies confirm the antimutagenic effects of Ilex paraguariensis in different models, from DNA double breaks in cell culture models to mice studies. Novel interesting work has emerged showing significant effect on weight reduction both in mice and in rat models. Some mechanisms involved are inhibition of pancreatic lipase, activation of AMPK and uncoupling of electron transport. Intervention studies in animals have provided strong evidence of anti-inflammatory effects of Ilex paraguariensis, notably protecting cigarette-induced lung inflammation acting on macrophage migration and inactivating matrix-metalloproteinase. Research on the effects of Ilex paraguariensis in health and disease has confirmed its antioxidant, anti-inflammatory, antimutagenic and lipid-lowering activities. Although we are still waiting for the double-blind, randomized prospective clinical trial, the evidence seems to provide support for beneficial effects of mate drinking on chronic diseases with inflammatory component and lipid metabolism disorders., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Groundwater arsenic contamination has been a health hazard for West Bengal, India. Oxidative stress to DNA is recognized as an underlying mechanism of arsenic carcinogenicity. A phytochemical, curcumin, from turmeric appears to be potent antioxidant and antimutagenic agent. DNA damage prevention with curcumin could be an effective strategy to combat arsenic toxicity. This field trial in Chakdah block of West Bengal evaluated the role of curcumin against the genotoxic effects of arsenic. DNA damage in human lymphocytes was assessed by comet assay and fluorescence-activated DNA unwinding assay. Curcumin was analyzed in blood by high performance liquid chromatography (HPLC). Arsenic induced oxidative stress and elucidation of the antagonistic role of curcumin was done by observation on reactive oxygen species (ROS) generation, lipid peroxidation and protein carbonyl. Antioxidant enzymes like catalase, superoxide dismutase, glutathione reductase, glutathioneS-transferase, glutathione peroxidase and non-enzymatic glutathione were also analyzed. The blood samples of the endemic regions showed severe DNA damage with increased levels of ROS and lipid peroxidation. The antioxidants were found with depleted activity. Three months curcumin intervention reduced the DNA damage, retarded ROS generation and lipid peroxidation and raised the level of antioxidant activity. Thus curcumin may have some protective role against the DNA damage caused by arsenic.

Oxidative damage to biomolecules occurs by the accumulation of molecular damage due to free radicals and/or a diminution of antioxidant protection. The aim of this study was to evaluate the protection of organic and conventional purple grape juices in brain, liver, and plasma from adult Wistar rats (7 months old) against the oxidative damage provoked by carbon tetrachloride (CCl(4)). Adult rats were divided into three groups (control, conventional purple grape juice, and organic purple grape juice). Half of the rats received CCl(4), and the other half received the vehicle (vegetable oil). The chemical analytical determination showed that the highest levels of total phenolic, resveratrol, and catechins were seen in organic purple grape juices. Considering the treatment groups, it was observed that in all tissues (brain structures and liver) and plasma, CCl(4) treatment increased the lipid peroxidation (LP) levels. Both grape juices were capable to reduce LP levels in cerebral cortex and hippocampus; however, in the striatum and substantia nigra only the organic grape juice reduced LP level. CCl(4) caused an increase in catalase activity in cerebral cortex, hippocampus, and substantia nigra and in superoxide dismutase activity in substantia nigra. This increase was reduced by both juices in substantia nigra and hippocampus structures (P < .05). In the alkaline version of the comet assay performed on whole blood, it was observed that CCl(4) was capable of inducing mainly DNA damage class 4 and 3 frequencies, which was significantly reduced in groups that received both purple grape juices. This implies that both grape juices have an important antigenotoxic activity.

The extract enriched in total oligomer flavonoids (TOF), and the aqueous, methanol, and ethyl acetate extracts of Acacia salicina were investigated for their polyphenolic compound content, antioxidative activity in the nitro blue tetrazolium/riboflavin assay system, antibacterial activity against Gram-positive and Gram-negative bacterial reference strains, antigenotoxic activity tested with the Ames assay, and cytotoxic activity against the K562 human chronic myelogenous leukemia cell line and L1210 leukemia murine cells. TOF extract was effective at inhibiting nitro blue tetrazolium reduction by superoxide radical in a nonenzymatic O(2)(*-)-generating system. Significant activity against bacterial reference strains Staphylococcus aureus, Enterococcus faecalis, Salmonella enteritidis, and Salmonella typhimurium was shown with all the tested extracts. These extracts significantly decreased the genotoxicity induced by sodium azide and 4-nitro-o-phenylenediamine. A pronounced cytotoxic effect on both leukemia cell lines was detected in TOF, methanolic and ethyl acetate extracts. The antioxidant, antimicrobial, antigenotoxic, and cytotoxic activities exhibited by A. salicina depended on the chemical composition of the tested extracts.

The hepatopulmonary syndrome (HPS) occurs when intrapulmonary dilatation causes hypoxemia in cirrhosis. The free radicals may play a significant contributory role in the progression of HPS, and flavonoid agents could protect against deleterious effects of free radicals. The flavonoid quercetin was evaluated in an experimental model of biliary cirrhosis induced by bile duct ligation (BDL) in rats. Quercetin was administered at 50mg/kg for 14 days to cirrhotic and non-cirrhotic rats. Bone marrow was extracted from animals to analyze micronuclei. Lung, liver and blood were extracted to detect DNA damage using the comet assay. The results showed that the micronuclei and DNA damages to lung and liver were increased in BDL rats. Quercetin caused no damage to the DNA while decreasing the occurrence of micronucleated cells in bone marrow as well as DNA damage to lung and liver in cirrhotic rats. Quercetin showed antimutagenic activity against hydroperoxides as evaluated by the oxidative stress sensitive bacterial strains TA102 Salmonella typhimurium and IC203 Escherichia coli, suggesting protection by free radical scavenging. In Saccharomyces cerevisie yeast strains lacking mitochondrial or cytosolic superoxide dismutase, these results indicate that quercetin protects cells by induction of antioxidant enzymes. The present study is the first report of genotoxic/antigenotoxic effects of quercetin in a model of animal cirrhosis. In this model, quercetin was not able to induce genotoxicity and, conversely, it increased the genomic stability in the cirrhotic rats, suggesting beneficial effects, probably by its antioxidant properties.

We evaluated the effects of pretreatment with ethanolic neem leaf extract on 7,12-dimethylbenz[a]anthracene (DMBA)-induced genotoxicity and oxidative stress in male Swiss albino mice. The frequency of bone marrow micronuclei, the extent of hepatic lipid peroxidation and the status of antioxidants-reduced glutathione (GSH), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) were used as intermediate biomarkers of chemoprotection. In DMBA-treated mice, the increases in micronuclei and lipid peroxides were accompanied by compromised antioxidant defenses. Pretreatment with ethanolic neem leaf extract (200 mg/kg body weight) significantly reduced DMBA-induced micronuclei and lipid peroxides and enhanced GSH-dependent antioxidant activities. The results of the present study suggest that ethanolic neem leaf extract exerts protective effects against DMBA-induced genotoxicity and oxidative stress by enhancing the antioxidant status.

To estimate the preventive potential of Japanese rice bran (Oryza sativa japonica) against the oxygen radical-related chronic diseases such as cardio-vascular diseases and cancer, antioxidative and antigenotoxic activities of the rice bran extracts were analyzed by using assay systems for lipid peroxidation and genotoxin-induced umu gene expression. When effects of the rice bran extracts under different extraction conditions on hydroperoxide generation from auto-oxidized linoleic acid were examined using aluminum chloride method, the water extract showed strong antioxidant activity, but the methanol and acetone extracts did not exhibit significant activity. The water extract of rice bran was divided into the ethanol-precipitable (EP) and supernatant fractions, and EP fraction showed the dominant antioxidant activity, but the supernatant fraction did not exhibit significant antioxidant activity. When the effect of EP fraction on umu C gene expression in SOS response associated with DNA damage in Salmonella typhimurium (TA 1535/pSK 1002) induced by 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1) was analyzed, it showed a dose-dependent suppressive activity against Trp-P-1-induced umu C gene expression. The bio-chemical analysis of EP fraction indicates that the major antioxidative and antigenotoxic activity of EP fraction is associated with a proteinous component with the molecular weight of more than 30 KDa. As a possible active principle for the antioxidative and antigenotoxic activity in EP fraction, the strong activity of an oxygen radical-scavenging enzyme, peroxidase was detected, and the purified horseradish peroxidase also caused the similar antioxidative and antigenotoxic activities. The significance of this finding is discussed from the viewpoint of the preventive role of rice bran against oxygen radical-related chronic diseases., (Copyright (c) 2004 John Wiley & Sons, Ltd.)

Many of the cancers common in the Western world, including colon, prostate and breast cancers, are thought to relate to dietary habits. Of the known risk factors, many will act through increasing the probability of mutation. Recognised dietary mutagens include cooked meat compounds, N-nitroso compounds and fungal toxins, while high meat and saturated fat consumption, increasing rates of obesity, and regular consumption of alcohol and tobacco are all dietary trends that could indirectly enhance the probability of mutation. However, there are significant difficulties in implementing and sustaining major dietary changes necessary to reduce the population's intake of dietary mutagens. Dietary antimutagens may provide a means of slowing progression toward cancer, and be more acceptable to the population. Consideration of genetic mechanisms in cancer development suggest several distinct targets for intervention. Strategies that reduce mutagen uptake may be the most simple intervention, and the one least likely to result in undesirable side effects. Certain (but not all) types of dietary fibres appear to reduce mutation through this mechanism, as may certain probiotics and large planar molecules such as chlorophyllin. Antioxidants have been suggested to scavenge free radicals, and prevent their interactions with cellular DNA. Small molecule dietary antioxidants include ascorbic acid, Vitamin E, glutathione, various polyphenols and carotenoids. We found a statistically significant relationship between colon cancer incidence and soil selenium status across different regions of New Zealand. Additionally, a study of middle-aged men suggested that blood selenium levels lower than 100 ng/ml were inadequate for repair or surveillance of oxidative (and other) DNA damage. We suggest that selenium will be an important antimutagen, at least in New Zealand, possibly through antioxidant effects associated with selenium's role in enzymes associated with endogenous repair of DNA damage. Modulation of xenobiotic metabolizing enzymes is well recognised as cancer-protective, and is a property of various flavonoids and a number of sulfur-containing compounds. Many fruits and vegetables contain compounds that will protect against mutation and cancer by several mechanisms. For example, kiwifruit has antioxidant effects and may also affect DNA repair enzymes. Dietary folate may be a key factor in maintenance of methylation status, while enhanced overall levels of vitamins and minerals may retard the development of genomic instability. The combination of each of these factors could provide a sustainable intervention that might usefully delay the development of cancer in New Zealand and other populations. Although there are a range of potentially antimutagenic fruits, vegetables and cereals available to these populations, current intake is generally below the level necessary to protect from dietary or endogenous mutagens. Dietary supplementation may provide an alternative approach.

Background: DNA damage from micronutrient deficiencies has been suggested as one major cause of cancer. Therefore studies involving vitamin supplementation, particularly with those with anti-oxidant activity, in combating cancer have routinely been carried out in both in vivo and in vitro systems, but relatively much less in mice., Aims: The present study examines if L-Ascorbic acid (AA; vitamin C) administration has any protective abilities in combating p-DAB induced hepatocarcinogenesis in mice at cytogenetical, biochemical, histological and ultra-structural levels., Settings and Design: To test if AA had a protective action against genotoxicity, cytotoxicity and tissue damage in liver during p-dimethylaminoazobenezene (p-DAB) induced hepatocarcinogenesis in mice, a group of mice were chronically fed 0.06% p-DAB and 0.05% phenobarbital (PB) for a varying period of time (7, 15, 30, 60, 90 and 120 days). A sub-group of the p-DAB plus PB fed mice were also fed 1% L-ascorbic acid. Several assays were periodically conducted (at the six intervals of fixation) for determination of genotoxic (based on chromosomal, nuclear and sperm head anomalies), cytotoxic (based on the marker enzymes aspartate transaminase; AST, alanine aminotransferase; ALT; acid phosphatase; ACP; alkaline phosphatase; ALKP; lipid peroxidation; LPO); and tissue damaging (based on optical and electron microscopic studies of liver at day 60 only) effects in these different groups of mice as compared to normal healthy control., Methods and Material: Adult healthy mice of Swiss Albino strain, reared and maintained in the animal house of the Department of Zoology, Kalyani University, under supervision of Animal Welfare Committee (which oversees ethical issues), served as materials for the present study. Widely practiced standard technique has been followed for each protocol., Statistical Analysis Used: The significance test between different series of data was conducted by student's t-test., Results and Conclusions: The results of all these studies indicated that AA had protective action against p-DAB induced hepatocarcinogenesis in mice.

Twenty-nine Chinese medicinal herbs and three healthy herbal drinks made of those herbs in a food processing pilot plant were tested for their antioxidative, free radical scavenging, mutagenic and antimutagenic activities. Water extracts of herbs (with few exceptions) and herbal drinks showed free radical scavenging activity. All water extracts of herbs and herbal drinks showed no mutagenicity toward Salmonella typhimurium tester strains TA98 and TA100 used in the Ames mutagenic tests. In the antimutagenic tests, the mutagenic activity of 4-nitroquinoline N-oxide (NQNO) toward S. typhimurium TA98 was markedly inhibited by water extracts of herbs and herbal drinks. Based on the results, it is suggested that the herbal drinks manufactured in pilot-plant scale are safe and can be served as health-promoting drinks for the public.

The effect of consumption of Brussels sprouts on levels of 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG) in human urine was investigated in 10 healthy, male, non-smoking volunteers. Following a 3 week run-in period, five volunteers continued on a diet free of cruciferous vegetables for a subsequent 3 week intervention period (control group), while the other five (sprouts group) consumed 300 g of cooked Brussels sprouts per day, at the expense of 300 g of a glucosinolate-free vegetable. Levels of 8-oxodG in 24 h urine samples were measured by HPLC. In the control group there was no difference between the two periods in levels of 8-oxodG (P = 0.72). In contrast, in the sprouts group the levels of 8-oxodG were decreased by 28% during the intervention period (P = 0.039). The present findings support the results of epidemiologic studies that consumption of cruciferous vegetables may result in a decreased cancer risk.