Effects of dietary grape seed extract on growth performance,amino acid digestibility and plasma lipids and mineral content in broiler chicks

Polyphenols are chemically and biologically active compounds. Grape seed extracts (GSEs) have been widely used as a human food supplement for health promotion and disease prevention. However, there is little information regarding its application in animal feeds. An experiment was conducted to investigate the effect of inclusion of GSE at 0.025, 0.25, 2.5 and 5.0 g/kg in a wheat soya bean control diet on growth performance, protein and amino acid (AA) digestibility and plasma lipid and mineral concentrations in broiler chickens at 21 days of age. Performance was not affected by dietary treatment except in the case of birds fed the diet with the highest GSE concentration, which showed a worsening of weight gain and feed conversion. Apparent ileal digestibility (AID) of protein was significantly reduced in the birds fed the highest concentration of GSE, which also had a reduction on the AID of arginine, histidine, phenylalanine, cystine, glutamic acid and proline compared with those fed control diet. The inclusion of graded concentration of GSE in the chicken diets caused a significant linear decrease in the concentrations of plasma copper, iron and zinc. Plasma cholesterol, triglycerides and lipoproteins (high-density lipoprotein, low-density lipoprotein and very-low-density lipoprotein) concentrations were not affected by dietary GSE. In conclusion, this study demonstrated that incorporation of GSE in chicken diets up to 2.5 g/kg had no adverse effect on growth performance or protein and AA digestibility. Feed conversion was reduced and growth rate was retarded, when chickens were fed 5 g/kg of GSE. This study also indicated that grape polyphenols reduce the free plasma minerals.     

Phytochemical and Biological Activities in Limonium Species Collected in Different Biotopes of Tunisia

A particular interest is nowadays given to natural antioxidants occurring in foods which can reduce the risk of several diseases through their protective effect. The genus Limonium is widely distributed in different salt regions of Tunisia and known in traditional medicine for the presence of highly effective viral and bacterial replication inhibitors. Limonium leaves have possible beneficial effects on human health for their antioxidant activities and free radical scavenging abilities. To exploit the potential of plants from extreme environments as new sources of natural antioxidants, we studied the extracts from leaves of eight Limonium species growing in extreme environments in Tunisia. Antioxidant molecules (polyphenols, flavonoids, flavonols, ascorbate, tocopherols), in vitro (DPPH, ORAC) and ex vivo antioxidant potential on human erythrocytes, antioxidant enzymes activities (superoxide dismutase, peroxidases, glutathione reductase) were evaluated to identify the species with the best antioxidant capacity. The results showed variability among the species considered in function of the environmental conditions of their natural biotopes, as for the antioxidants measured. In particular, L. vulgare from Oued Rane biotope, characterized by dryness and high temperatures, was the species with the highest enzymatic activity and antioxidant capacity, making it interesting as possible edible halophyte plant or as food complement.     

Aerobic microbial degradation of alginate in Laminaria hyperborea stipes containing different levels of polyphenols

The polyphenols present in brown seaweed tissue may seriously affect aerobic microbial degradation, particularly the alginate present. Laminaria hyperborea stipes, harvested at 59 °N off the Norwegian coast in autumn, were degraded at different levels of polyphenols in aerated batch reactors at 35 °C and pH 7. This was achieved by manipulating the relative amounts of peripheral tissue, by removing or adding the mechanically peeled outer phenolic layer, using standardized inocula already adapted to L. hyperborea degradation. The degradation of organic matter was clearly depressed by increasing the amount of peripheral tissue. Alginate lyase activity was also negatively correlated to the amount of peripheral tissue loaded, presumably due to the release of reactive polyphenols. The total digestion rates of alginate were reduced by more than a factor of two at enhanced amounts of peripheral tissue. The guluronic content of extracted Na-alginate increased during the degradation, despite the presence of significant amounts of guluronate specific alginate lyase activity. This revised version was published online in August 2006 with corrections to the Cover Date.     

Treatment with fungicides influences phytochemical quality of blackcurrant juice

The impact of fungicide treatment on fungal infection and blackcurrant juice quality was examined in a series of field experiments over the course of 2 years. Fungicide treatment reduced the incidence of foliar disease and resulted in changes in the concentration of sugars, organic acids, polyphenols and anthocyanins in blackcurrant juice. Treatment with Signum^® (containing pyraclostrobin, a strobilurin, and boscalid, a succinate dehydrogenase inhibitor) enhanced glucose, fructose and total sugar content in one treatment year but not in another. Treatment with Signum or Filan^® (containing boscalid only) caused a reduction in the key organic acid citrate. Treatment with Signum or Platoon^® (containing pyraclostrobin only) enhanced total polyphenol and anthocyanin content of juices. The data suggest a beneficial impact of fungicide treatment not only on disease control but also on juice phytochemistry.     

Antinociceptive,Anti-Hyperalgesia and Antiallodynic Activities of Polyphenol Rich Extract from Shorea roxburghii against Cyclophosphamide Induced Peripheral Neuropathy

Cyclophosphamide (CYP) is a widely used antineoplastic and immunosuppressive drug, however, despite its efficacy, it has shown extensive multiple organ toxicities, including peripheral neuropathy which significantly affects the quality of life of cancer patients. This study elucidated the protective properties of Shorea roxburghii polyphenol extract (SLPE) in CYP-induced peripheral neuropathy. Rats were treated with SLPE (100 and 400 mg/kg) for five weeks plus CYP once a week from the second week of SLPE treatment. Using UHPLC-QTOF-MS, 54 polyphenolic compounds were identified in SLPE extract. After the treatment period the antinociceptive, anti-hyperalgesia and antiallodynic effects was evaluated using formalin paw edema, acetic acid abdominal writhing, hot plate, tail immersion and von Frey filament tests. While the locomotive and motor coordination effects were evaluated by open field and rotarod tests. The administration of CYP led to significant increases in mechanical and thermal hyperalgesia, in addition to hyper-nociceptive responses in the formalin and acetic acid writhing tests. CYP also significantly reduced locomotive activity and motor coordination. SLPE significantly protected against CYP-induced mechanical and thermal hyperalgesia. Furthermore, SLPE displayed robust antinociceptive effect by counteracting formalin and acetic acid induced hyper-nociception. In addition, SLPE increased the locomotive activity as well as the grip and motor coordination of the CYP treated rats. In conclusion, these results revealed the protective effects of SLPE against CYP-induced peripheral neuropathy and could be an effective therapeutic remedy for chemotherapy induced peripheral neuropathy.     

Heat shock responses of bean plants: involvement of free radicals, antioxidants and free radical/active oxygen scavenging systems

In non-acclimated bean plants heat shock induced oxidative damage (increase of free radical concentration and drop of bound thiols, indicating aggregation of proteins) which was regulated by the enhanced activities of peroxidase and superoxide dismutase, as well as by the accumulation of polyphenols and especially of polyamines. In the plants acclimated to high temperature no oxidative damage occurred following heat shock. This revised version was published online in July 2006 with corrections to the Cover Date.