Elevated XO activity enhances lipid

Elevated XO activity enhances lipid peroxidation due to the attendant excessive generation of reactive oxygen species (ROS), decreases in the levels of non-protein antioxidants including reduced glutathione (GSH), vitamin C and vitamin E; and the inflammation associated with neutrophil infiltration [31]. Lipid peroxidation is the oxidative damage of lipids, especially the polyunsaturated fatty acids that are very susceptible to oxidative attack, by ROS and transition metal ions; and it is known to play a key role in cell injury [49]. This is due to the diverse cytotoxic products, mostly aldehydes such as malondialdehyde (MDA) it yields [50]. These cytotoxic aldehydes have been implicated in the pathogenesis of a number of oxidative stress-induced inflammatory diseases [51] such as gouty arthritis. Under such condition, the antioxidant status of the affected tissues is attenuated; thereby over-exposing the cytokine inhibitors to oxidative damage, and aggravating the inflammatory condition. The peroxidation of membrane lipids and the consequent oxidative damage to cell membrane may disrupt the membrane transport, ionic channels, proteins and deactivate membrane-associated enzymes; the membrane lipid bilayer itself may become more permeable due to oxidative damage [33]. Hence, the ability of the extract to inhibit lipid peroxidation in the kidney, liver and lungs tissues homogenates of rats indicates its ability to prevent and/or ameliorate oxidative damage to the lipids in the membranes of the cells of these three important organs; thereby maintaining the integrity of their membrane structure and functionality. Furthermore, since the ROS generated by lipid peroxidation are involved in the pathogenesis of several other diseases such as diabetes mellitus, cardiovascular diseases and carcinogenesis, XO inhibitors, including polyphenolics, could also be useful for the prevention and management of many other diseases [44]. This may explain why T. tetraptera fruit has other medicinal uses as stated earlier. The lipid peroxidation inhibitory activity of the T. tetraptera fruit extract could be attributed to its flavonoids and phenolic acids. This is in agreement with our earlier report that Mangifera indica and Mucuna urens seeds extracts rich in these two classes of phenolics inhibited Fe2+-induced lipid peroxidation in rat pancreas homogenate [34].
Conclusion Phenolics extract of T. tetraptera fruits inhibited xanthine oxidase and F2+-induced lipid peroxidation in the kidney, liver and lungs tissues of rats in vitro. These activities could be attributed to the combined effect of the flavonoids and phenolic acids present in the fruits. Therefore, T. tetraptera fruits might be a promising functional food that could be explored for the prevention and management of hyperuricaemia and its associated disease conditions.
Conflict of interest statement
Acknowledgement
Introduction Flour is an important food ingredient for humans. It contains some basic nutrients such as fibre, protein and vitamins [1]. Although flour is a central component of human diet, there have been few reports concerning the volatile organic compounds (VOCs) in this staple food until recently [2]. Identification of the VOCs released by flour can help us know the components of its flavour and judge its quality over time during storage [3]. Tribolium castaneum (Herbst) is one of the most common insects affecting stored cereal grains, beans, nuts and other durable agricultural products all over the world [4,5]. The presence of this insect in flour, not only causes direct damage, but also results in the deterioration of grain quality, loss of feeding value for stock, and hygiene problems like off-odour damage [6]. Reliable and simple methods to detect the existence of pest infestations in stored products are critically important throughout the supply chain to ensure, for example, the maintenance of grain quality during domestic storage and compliance with international quarantine requirements [7]. The typical approaches for detecting insects in stored grain are based on collecting representative samples of grain from stacks, trucks and rail bogies, and manually inspecting these samples for adult insects by sieving, flotation and Berlese-funnels [8]. These techniques can easily trap or detect adult insects but are not suitable for immature insects. X-ray imaging and near infrared reflectance (NIR) spectroscopy have been studied for the detection of stored grain insects as they can detect hidden insects [9]. However, the operation of these technologies is relatively complicated and there has been no success with in situ detection.