Oxidative Stress and Low-Grade Inflammation in Polycystic Ovary Syndrome: Controversies and New Insights

The pathophysiology of Polycystic Ovary Syndrome (PCOS) is quite complex and different mechanisms could contribute to hyperandrogenism and anovulation, which are the main features of the syndrome. Obesity and insulin-resistance are claimed as the principal factors contributing to the clinical presentation; in normal weight PCOS either, increased visceral adipose tissue has been described. However, their role is still debated, as debated are the biochemical markers linked to obesity per se. Oxidative stress (OS) and low-grade inflammation (LGI) have recently been a matter of researcher attention; they can influence each other in a reciprocal vicious cycle. In this review, we summarize the main mechanism of radical generation and the link with LGI. Furthermore, we discuss papers in favor or against the role of obesity as the first pathogenetic factor, and show how OS itself, on the contrary, can induce obesity and insulin resistance; in particular, the role of GH-IGF-1 axis is highlighted. Finally, the possible consequences on vitamin D synthesis and activation on the immune system are briefly discussed. This review intends to underline the key role of oxidative stress and low-grade inflammation in the physiopathology of PCOS, they can cause or worsen obesity, insulin-resistance, vitamin D deficiency, and immune dyscrasia, suggesting an inverse interaction to what is usually considered.     

A comprehensive review of wheat phytochemicals: From farm to fork and beyond

The health benefits of whole wheat consumption can be partially attributed to wheat's phytochemicals, including phenolic acids, flavonoids, alkylresorcinols, carotenoids, phytosterols, tocopherols, and tocotrienols. It is of increasing interest to produce whole wheat products that are rich in bioactive phytochemicals. This review provides the fundamentals of the chemistry, extraction, and occurrence of wheat phytochemicals and includes critical discussion of several long-lasting issues: (1) the commonly used nomenclature on distribution of wheat phenolic acids, namely, soluble-free, soluble-conjugated, and insoluble-bound phenolic acids; (2) different extraction protocols for wheat phytochemicals; and (3) the chemistry and application of in vitro antioxidant assays. This review further discusses recent advances on the effects of genotypes, environments, field management, and processing techniques including ultrafine grinding, germination, fermentation, enzymatic treatments, thermal treatments, and food processing. These results need to be interpreted with care due to varied sample preparation protocols and limitations of in vitro assays. The bioaccessibility, bioavailability, metabolism, and potential health benefits of wheat phytochemicals are also reviewed. This comprehensive and critical review will benefit scientific researchers in the field of bioactive compounds of cereal grains and also those in the cereal food industry to produce high-quality functional foods.     

Organofluorine Hydrazone Derivatives as Multifunctional Anti-Alzheimer's Agents with CK2 Inhibitory and Antioxidant Features

A set of novel hydrazone derivatives were synthesized and analyzed for their biological activities. The compounds were tested for their inhibitory effect on the phosphorylating activity of the protein kinase CK2, and their antioxidant activity was also determined in three commonly used assays. The hydrazones were evaluated for their radical scavenging against the DPPH, ABTS and peroxyl radicals. Several compounds have been identified as good antioxidants as well as potent protein kinase CK2 inhibitors. Most hydrazones containing a 4-N(CH₃)₂ residue or perfluorinated phenyl rings showed high activity in the radical-scavenging assays and possess nanomolar IC₅₀ values in the kinase assays.     

Furan fatty acid concentrations in tea infusions prepared from green,black, and herbal teas

Furan fatty acids (FuFAs) are valuable antioxidants with highly effective radical scavenging properties which are widely distributed at low levels in food. Previous research indicated that tea is a valuable source of FuFAs. However, tea is only consumed in form of infusions. To fill this gap, we prepared infusions from different herbal, green, and black teas. Initial measurements with GC-MSMS of tea verified previous findings that 11-(3,4-dimethyl-5-penylfuran-2-yl)-undecanoic acid (11D5) was the prevalent FuFA in tea matrix. Therefore, 11D5 was quantified in tea infusions by means of UHPLC-MSMS equipment after mild alkaline hydrolysis. While herbal tea infusions were low or free of FuFAs, 11D5 was detectable in all samples of green and black tea infusions. Amounts of 11D5 were higher in green tea than in black tea. Moreover, Darjeeling tea infusions were by ~30% richer in 11D5 than black and green teas from other regions. Each cup of green and black tea infusion may provide 20–60 μg 11D5, which is about 5% of the amounts found in tea samples. Spread over the day, regular tea consumption may contribute to the intake of valuable FuFAs.     

Recent trends for the employment of jumbo squid (Dosidicus gigas) by-products as a source of bioactive compounds with nutritional,functional and preservative applications: a review

Only 50%–60% of total seafood catch is used for human consumption, seafood processing being considered as one of the main sources of by-products. Among marine species, jumbo squid (JS; Dosidicus gigas) represents the most important squid fishery, showing an increasing economic interest in many countries. As for any other marine species, the regular cleaning, dressing and processing produce high quantities of by-products (skin, head, fins, viscera, tentacles, unclaimed mantle, etc.) that are rich in many nutrients (proteins, lipids, minerals, vitamins, enzymes, biopolymers, etc.). This review compiles information about extraction and employment of JS by-products with the aim of enhancing their economic value and reduce environmental drawbacks. A special emphasis is given to the relevance in developing methods susceptible to transform by-products into useful and profitable products susceptible to be applied in several industries such as food, medicine, agrochemical or pharmaceutical. Future possible trends for widening this profitable use are mentioned.     

Twenty-five years of total antioxidant capacity measurement of foods and biological fluids: merits and limitations

This review summarises 25 years of investigations on antioxidants research in foods and biological fluids and critically analyses the merits and limitations of using the total antioxidant capacity (TAC) measurement in the metabolomic era. An enormous bulk of knowledge was produced regarding the antioxidant capacity of foods and large TAC databases were developed. A direct link between a food TAC value and any health benefit is erroneous and has led to several cases of consumer deception. However, the striking epidemiological evidence associating a high dietary TAC with some disease prevention and the availability of well-constructed TAC databases deserve attention and must be taken into account to establish the usefulness of measuring TAC in both foods and biological samples. The in vivo TAC measurement, usually performed in plasma, is influenced by many external factors, such as dietary habits, as well as environmental and behavioural factors, which are integrated towards homeostatic control by fine physiological mechanisms with high inter-individual variability. Therefore, plasma TAC cannot be considered as a unique biomarker of individual antioxidant status. However, the combined evaluation of plasma TAC with known markers of disease, individual metabolism, inflammation and genetics, as well as with markers of gut microbiota composition and activity, may lead to the identification of populations that are more responsive to food/diet TAC. In this framework, the appropriate use of TAC measurement both in food and in vivo can still provide support for the interpretation of complex phenomena and be a tool for sample screening when making a quick decision toward in-depth research investigations. © 2018 Society of Chemical Industry     

Antioxidant potential of extracts from peels and stems of yellow-fleshed and white cassava varieties

This study focused on the exploration of the potentials of extracting antioxidants from peels and stems of yellow-fleshed and white cassava varieties. The effect of particle size (0.2 and 0.5 mm) and variety on the phenolic content and antioxidant activity was assessed. The peels of the yellow-fleshed cassava variety with a particle size of 0.2 mm showed the highest phenolic content with 681.5 GAE mg 100 g⁻¹ and antioxidant activity of 19% and 425 μM TE g⁻¹ dry matter using DPPH and FRAP assays respectively. The stems of the white cassava with a particle size of 0.2 mm exhibited high phenolic content (442.4 GAE mg 100 g⁻¹) and antioxidant activity of 12.8% and 234 μM TE g⁻¹, better than the stem of the yellow-fleshed cassava. These results indicate that phenolic and antioxidant extractions were influenced by variety, the plant parts and particle size for the antioxidant assays.     

Extraction of lipid-soluble antioxidants from rosemary leaves using vegetable oils

The objective of this research was to extract carnosic acid and carnosol, natural lipid-soluble antioxidants, from rosemary leaves without the use of chemical aid. Three different vegetable oils [high oleic soybean oil (HOSO), peanut oil (PO) and cottonseed oil (CO)] were used as the medium for extracting rosemary's lipid-soluble antioxidants. Dried rosemary leaves were ground into fine particles, added two of the selected vegetable oils, mixed and heated. The vegetable oil containing the extracted antioxidants was filtered from the rosemary particles and analysed using high-performance liquid chromatography (HPLC). As a control, a common extraction method using ethanol was performed to compare the oil extraction efficiency for carnosic acid and carnosol. HPLC analysis confirmed the presence of carnosic acid and carnosol in all three vegetable oil solutions. Compared to the ethanol extraction, a higher level of the carnosic acid was found in the vegetable oil solutions. Among the vegetable oils, high oleic soybean oil contained the most carnosic acid; however, there were similar amounts of carnosol in all three vegetable oil solutions. The extractions' efficacy was tested on soybean oil's (SO) oxidative stability by adding 2% (w/w) of the antioxidant–vegetable oil solution. The results obtained from peroxide value (PV) and p-anisidine value (AnV) analysis documented a significantly lower degree of oxidation in the soybean oil containing the extracted antioxidant solutions, compared to the pure soybean oil.