Evolution of phenolic compounds was studied during spontaneous and controlled fermentations of “Chétoui” cultivar olives at three degree of ripeness. Both spontaneous and controlled fermentations led ...to an important loss of total phenolic compounds with a reduction rate of 32–58%. Consequently, the antioxidant activity decreased by 50–72%. After fermentations, hydroxytyrosol and caffeic acid concentrations increased, whilst protocatechuic acid, ferulic acid and oleuropein concentrations decreased. The hydroxytyrosol concentration in black olives increased from 165
mg/100
g dry weight to 312 and 380
mg/100
g dry weight, respectively, after spontaneous and controlled fermentation. The oleuropein concentration in green olives decreased from 266
mg/100
g dry weight to 30.7 and 16.1
mg/100
g dry weight, respectively, after spontaneous and controlled fermentation. During olive fermentation, phenolic loss is essentially due to the diffusion of these compounds into the brine; the main phenolic compound identified and quantified in the different brines was hydroxytyrosol. To preserve antioxidant quality of table olives it is necessary to use a controlled process to minimise phenolic compound loss.
Bio‐oil to hydrocarbon oil: An active, selective, and stable catalyst (Ni supported in zeolite HZSM‐5) allows the conversion of a wide variety of CO and CO bonds in n‐hexane‐extracted pyrolysis oil ...into hydrocarbons through a cascade of hydrogenation, hydrolysis, dehydration, and dehydroaromatization reactions. Quantitative yields of C5–C9 gasoline‐range hydrocarbons are obtained under mild conditions in water.
Neuroprotection is the preservation of function and networks of neural tissues from damages caused by various agents, as well as neurodegenerative diseases such as Parkinson's, Alzheimer's, ...Huntington's diseases, and multiple sclerosis. Hesperidin, a flavanone glycoside, is a natural phenolic compound with a wide range of biological effects. Mounting evidence has demonstrated that hesperidin possesses inhibitory effect against development of neurodegenerative diseases. Our review discusses neuropharmacological mechanisms for preventive and therapeutic effects of hesperidin in neurodegenerative diseases. In addition, the review examines clinical evidence confirming its neuroprotective function. Various cellular and animal models specific to neurodegenerative diseases have been conducted to evaluate the underlying neuropharmacological mechanisms of hesperidin. Neuroprotective potential of this flavonoid is mediated by improvement of neural growth factors and endogenous antioxidant defense functions, diminishing neuro-inflammatory and apoptotic pathways. Despite the various preclinical studies on the role of hesperidin in the neurodegenerative diseases, less is known about its definite effect on humans. A limited number of clinical trials showed that hesperidin-enriched dietary supplements can significantly improve cerebral blood flow, cognition, and memory performance. Further clinical trials are also required for confirming neuroprotective efficacy of this natural flavonoid and evaluating its safety profile.
This study aimed to investigate the impact of different solvents (water, 60% methanol, 60% ethanol and 60% acetone) and methods (conventional solvent extraction, ultrasound-assisted extraction, ...microwave-assisted extraction and ultrasound-microwave assisted extraction) on the phenolic profile and antioxidant activity of jackfruit (Artocarpus heterophyllus Lam.) pulp. The Folin-Ciocalteu assay was used to determine the total phenolic content (TPC), and antioxidant activity was measured by DPPH and ABTS assays. The phenolic profiles in different extracts were identified using the UPLC-ESI-Q-TOF-MS/MS technique. The results showed that significant differences (p < 0.05) in TPC were found among different extraction methods, the microwave-assisted extraction with 60% ethanol had the highest TPC (2.40 mg GAE/g) compared with the extracts obtained from other methods. Meanwhile, the highest DPPH radical and ABTS radical cation was found in the 60% ethanol-MAE extracts. Correlation analysis further showed a significant positive correlation between TPC and antioxidant activity (R2 > 0.8, p < 0.001). Seventy-eight phenolic compounds were identified by UPLC-ESI-Q-TOF-MS/MS analysis. The most abundant phenolic compounds in jackfruit pulp were identified in negative mode, with 60% ethanol-MAE being the most effective. The quantity of phenolic compounds extracted varied with different extraction methods indicated that the extraction methods had effects on the phytochemical characteristics.
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•Polyphenols from jackfruit pulp were extracted using four different extraction methods.•UPLC-ESI-Q-TOF-MS/MS is applied to identify phenolics in different extracts.•Ethanol-MAE extracts had the strongest antioxidant activity.•The antioxidant activity and TPC of the extracts have a significant positive correlation.
The immoderate amount of phenol found in the water reservoir, i.e., river and municipal drain, has served as one major contributor to the scarcity of potable water worldwide. Many conventional ...methods have been applied to tackle polluted phenol water but suffer from various drawbacks. Special attention has been given to the photocatalytic membrane due to its ability to degrade phenol and sieving, a 2-in-1 function. Hence, this extensive report reviewed the extant trends in phenol removal such as distillation, adsorption, biodegradation, chemical oxidation, electrochemical oxidation, enzymatic treatment, and membrane technology. The in-depth discussion concerning the utilization of membrane as photocatalyst support media is also conferred, which could be the trendsetter in several years to come.
It is difficult to strengthen and toughen epoxy resin (EP) and concurrently obtain good flame retardancy. A novel flame retardant marked as TFD was prepared by tyrosine (Tyr), furfuraldehyde (FA) and ...9,10-Dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) and co-cured with EP. Only 6 wt% TFD makes EP achieve UL-94 V0 and limited oxygen index (LOI) value 32.4 vol% revealing the high flame retardant efficiency. Furthermore, the tensile and impact strength of EP-8TFD are 29.3 % and 84.4 % higher than that of EP indicating strengthening and toughening effect of TFD. TFD can chemically bond into EP networks via its carboxyl and phenolic hydroxyl reacting with EP leading to good tensile properties. The high rigidity of DOPO forms holes between molecular chains, which eliminates stress concentration and improves impact strength. The strength, toughness and flame retardancy of EP are regulated by simple molecular structure, which provides a good idea for integration of structure and performance.
A tyrosine-based flame retardant TFD modify the flame retardacy, strength and toughness of epoxy resin simultaneously. Display omitted
•TFD was synthesized by using tyrosine, furfuraldehyde and 9,10-Dihydro-9-oxa-10-phosphaphenanthrene 10-oxide.•Toughening and strengthening epoxy resin with excellent flame retardancy is obtained by using TFD.•TFD react with EP group leading to good tensile strength and cavitation effect of TFD leads to high impact strength.
Moringa oleifera is a plant valued for its properties and applications in Ethnomedicine. It is cultivated in India, tropical Africa, and America; some regions use their different tissues as food ...supplements. Although germination can increase seedlings' phytochemical content, few studies have described the phytochemical content of moringa seedlings during early growth. This study aimed to investigate and discuss the limited information dealing with moringa seed germination, sprout production, and seedlings' chemical composition. This bibliographical research was systematically and thoroughly conducted using some of the most internationally-recognized databases. M. oleifera plants are characterized by their ability to grow under adverse environmental conditions. Although they generally germinate at rates greater than 70%, this response depends on the altitude, light periods, temperature, and nutrient availability. Pre-germination treatments have also been reported to help improve germination yields; the most common is soaking exposure. The production of M. oleifera sprouts is a viable option for obtaining functional food as this process can increase the content of nutrients (e.g. lipids, proteins) and phytochemicals (glucosinolates and phenolic compounds). Also, sprouts can be used as additives to enrich conventional foods. It is concluded that there is little scientific information describing the germination process and the chemical composition of both moringa seeds and moringa sprouts. Therefore, it is a niche opportunity to build new research that helps fill the informational gaps mentioned above. Meanwhile, it is envisioned that biotic or abiotic agents might modulate the germination process and their chemical compounds.
•Olive leaves can be considered a byproduct of large interest in a biorefinery context.•Olive leaves offer many bioactive compounds with significant and potential applications.•Identifying the best ...olive leaf cultivars and suitable extraction methods is a key step.•A comparative study of different cultivars has been performed using an emerging technology.•Pressurized liquid extraction has been used for mannitol extraction from olive leaves.
Olive leaves are considered a promising source of bioactives such as phenolic compounds and mannitol. The extraction of high added value products is an issue of great interest and importance from the point of view of their exploitation. However, the content of these compounds can differ between cultivars and extraction methods. In this work, six olive leaves cultivars, including three wild cultivars, and two extraction processes (an innovative and alternative technique, pressurized liquid extraction, and a conventional Soxhlet extraction) were evaluated and compared towards the selective recovery of bioactive compounds. The wild cultivars showed the highest content of phenolic and flavonoid compounds, being oleuropein the compound present in higher amount. Findings also revealed that the highest mannitol content in the extracts was observed with the commercial cultivars, specifically in Arbequina. It is thus possible to decide which cultivars to use in order to obtain the highest yield of each bioproduct.
•Phytochemical profiles of selected dried fruits are compared.•The antioxidant efficacies of selected dried fruits are discussed.•Potential health benefits of selected dried fruits are ...highlighted.•Novel products and future perspectives of dried fruits are discussed.
Dried fruits, which serve as important healthful snacks worldwide, provide a concentrated form of fresh fruits. They are nutritionally equivalent to fresh fruits in smaller serving sizes, ranging from 30 to 43 g depending on the fruit, in current dietary recommendation in different countries. Daily consumption of dried fruits is recommended in order to gain full benefit of essential nutrients, health-promoting phytochemicals, and antioxidants that they contain, together with their desirable taste and aroma. Recently, much interest in the health benefits of dried fruits has led to many in vitro and in vivo (animal and human intervention) studies as well as the identification and quantification of various groups of phytochemicals. This review discusses phytochemical compositions, antioxidant efficacies, and potential health benefits of eight traditional dried fruits such as apples, apricots, dates, figs, peaches, pears, prunes, and raisins, together with dried cranberries. Novel product formulations and future perspectives of dried fruits are also discussed. Research findings from the existing literature published within the last 10 years have been compiled and summarised.
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