An update of aurones: food resource, health benefit, biosynthesis and application.

Aurones are a subclass of active flavonoids characterized with a scaffold of 2-benzylidene-3(2H)-benzofuranone. This type of chemicals are widely distributed in fruit, vegetable and flower, and contribute to human health. In this review, we summarize the natural aurones isolated from dietary plants. Their positive effects on immunomodulation, antioxidation, cancer prevention as well as maintaining the health status of cardiovascular, nervous system and liver organs are highlighted. The biosynthesis strategies of plant-derived aurones are elaborated to provide solutions for their limited natural abundance. The potential application of natural aurones in food coloration are also discussed. This paper combines the up-to-date information and gives a full image of dietary aurones.

Systematic review and meta-analysis of the efficacy of olprinone and MEFV gene in treating heart failure.

Cardiovascular failure is the main cause of death in industrialized societies. The results of recent studies have shown that some mutations in the MEFV gene are common in heart failure patients. For this reason, the study of mutations and genetic factors has been of great help in the treatment of this disease, but despite this, due to the heterogeneity of clinical symptoms, multiple pathophysiological processes, and environmental genetic factors, the complete understanding of the genetic causes of this disease is very complicated. As the new generation of phosphodiesterase (PDE) III inhibitor, olprinone, the inhibition of human heart PDE III by olprinone is highly selective. It is suitable for the treatment of acute heart failure (HF) and acute cardiac insufficiency after cardiac surgery. In this study Olprinone, milrinone, PDE inhibitors, cardiac failure, and HF were selected as the search terms to retrieve articles published between January 1999 and March 2022. RevMan5.3 and Stata were employed to analyze and evaluate the risk bias of the included articles. Besides, the Q test and heterogeneity were utilized to evaluate the heterogeneity between articles. The results of this research showed No heterogeneity was found between each research group. The sensitivity (Sen) and specificity (Spe) of the two methods were compared. Olprinone showed more significant therapeutic effects than other PDE inhibitors. Besides, the therapeutic effect on the patients with HF in the two groups was obvious. The incidence of postoperative adverse reactions among the patients without relieving HF was low. The influences on urine flow of the two group's demonstrated heterogeneity, and its effect revealed no statistical meaning. The meta-analysis confirmed that the Spe and Sen of olprinone treatment were higher than those of other PDE inhibitors. In terms of hemodynamics, there was little difference between various treatment methods.

Eco-friendly simultaneous extraction of pectins and phenolics from passion fruit (Passiflora edulis Sims) peel: Process optimization, physicochemical properties, and antioxidant activity.

The objective of this study was to simultaneously extract passion fruit (Passiflora edulis) peel pectins and phenolics using deep eutectic solvents, to evaluate their physicochemical properties and antioxidant activity. By taking L-proline: citric acid (Pro-CA) as the optimal solvent, the effect of extraction parameters on the yields of extracted passion fruit peel pectins (PFPP) and total phenolic content (TPC) was explored by response surfaces methodology (RSM). A maximum pectin yield (22.63%) and the highest TPC (9.68 mg GAE/g DW) were attained under 90 °C, extraction solvent pH = 2, extraction time of 120 min and L/S ratio of 20 mL/g. In addition, Pro-CA-extracted pectins (Pro-CA-PFPP) and HCl-extracted pectins (HCl-PFPP) were subjected to high performance gel permeation chromatography (HPGPC), Fourier transform infrared spectroscopy (FT-IR), thermogram analysis (TG/DTG) and rheological measurements. Results verified that the Mw and thermal stability of Pro-CA-PFPP were higher than those of HCl-PFPP. The PFPP solutions featured a non-Newtonian behavior, and compared with commercially pectin solution, PFPP solution exhibited a stronger antioxidant activity. Additionally, passion fruit peel extract (PFPE) exhibited stronger antioxidant effects than PFPP. The results of ultra-performance liquid chromatography hybrid triple quadrupole-linear ion trap mass spectrometry (UPLC-Qtrap-MS) and high performance liquid chromatography (HPLC) analysis showed that (-)-epigallocatechin, gallic acid, epicatechin, kaempferol-3-O-rutin and myricetin were the main phenolic compounds in PFPE and PFPP. Our results suggest that Pro-CA can be considered as an eco-friendly solvent for high-efficient extraction of high-value compounds from agricultural by-products.

Ultrasonic-assisted binding of canistel (Lucuma nervosa A.DC) seed starch with quercetin.

In order to provide a reference for improving the physicochemical properties of starch, the study of starch polyphenol complex interaction has aroused considerable interest. As a common method of starch modification, ultrasound can make starch granules have voids and cracks, and make starch and polyphenols combine more closely. In this research, canistel seed starch was modified by ultrasonic treatment alone or combined with quercetin. The molecular structure, particle characteristics and properties of starch were evaluated. With the increase of ultrasonic temperature, the particle size of the dextrinized starch granules increased, but the addition of quercetin could protect the destruction of starch granule size by ultrasonic; X-ray diffraction and infrared spectra indicated that quercetin was bound to the surface of canistel seed starch through hydrogen bonding, and the complex and the original starch had the same crystal structure and increased crystallinity; by molecular simulation, quercetin bound inside the starch molecular helix preserved the crystalline helical configuration of starch to some extent and inhibited the complete unhelicalization of starch molecules. Meanwhile, hydrogen bonding was the main driving force for the binding of starch molecules to quercetin, and van der Waals interactions also promoted the binding of both. In the physicochemical properties, as the temperature increased after the combination of ultrasonic modified starch combined with quercetin, the solubility, swelling force and apparent viscosity of the compound increased significantly, and it has higher stability and shear resistance.

Advances in gas fumigation technologies for postharvest fruit preservation.

This work summarizes the application of gas fumigation technology in postharvest fruit quality management and related biochemical mechanisms in recent years. Gas fumigants mainly include SO2, ClO2, ozone, NO, CO, 1-MCP, essential oils, H2S and ethanol. This work indicated that gas fumigation preservatives can effectively improve postharvest fruit quality, which is mainly manifested in delaying senescence, inhibiting browning, controlling disease and alleviating chilling injury. Gas preservatives are mainly involved in postharvest fruit quality control in the roles of antifungal agent, anti-browning agent, redox agent, ethylene inhibitors, elicitor and pesticide remover. Different gas preservatives have different roles, but most of them have multiple roles at the same time in postharvest fruit quality management. In addition, the role of some gas preservatives with direct antifungal activity in the control of postharvest fruit diseases can also activate defense systems to improve fruit resistance. It should be noted that some gas fumigation treatments with slow-release effects have been developed recently, which may allow gas fumigation gases to perform better. Moreover, some gas fumigants can cause irrational side effects on the fruit and some combined treatments need to be found to counteract such side effects.

Stability and bioactivity evaluation of black pepper essential oil nanoemulsion.

Black pepper essential oil has the same disadvantages as other plant essential oils, such as volatilization, high sensitivity to light and heat and poor water solubility, which leads to great limitations in application. This study improved the stability and antibacterial properties of black pepper essential oil (BPEO) based on a nano-emulsification process. Tween 80 was selected as the emulsifier to prepare the BPEO nanoemulsion. Gas chromatograph - mass spectrometer (GC-MS) was used to analyze the composition of BPEO, of which d-limonene was the main component (37.41%). After emulsification, black pepper nanoemulsion was obtained (droplet size was 11.8 nm). The water solubility and stability of the emulsions at 25 °C were also improved with decreasing particle size. Antimicrobial properties of plant pathogens (Colletotrichum gloeosporioides, Botryodiplodia theobromae) and foodborne pathogens (Staphylococcus aureus, Escherichia coli) were evaluated by disk diffusion and other techniques for determining minimum inhibitory concentration (MIC) and minimal bactericidal concentration (MBC). With 12.5 mg mL-1 MIC and 25 mg mL-1 MBC, BPEO inhibited the growth of two tested plant pathogens and two foodborne pathogens. Essential oils (EO) were encapsulated in a nanoemulsion system to enhance the bacteriostatic effect of essential oils and reduce MIC and MBC concentrations. After emulsification, the biological activity (antimicrobial and antioxidant) of the BPEO nanoemulsion was considerably improved, nano-emulsification had certain significance for the study of EOs.

The Diuretic Effects of Coconut Water by Suppressing Aquaporin and Renin-Angiotensin-Aldosterone System in Saline-Loaded Rats.

The acute and prolonged diuretic effects of coconut water (CW) and the underlying mechanism were investigated with a saline-loaded rat model. In an acute diuretic experiment, CW could significantly increase urine excretion. In addition, the treatment of CW significantly increased urinary sodium and chloride ions, thereby considerably increasing the excretion of NaCl. However, the calcium concentration and pH value were not affected. In the prolonged diuretic experiment, CW dramatically increased the urine output and urine electrolyte concentrations (Na+, K+, and Cl-). Furthermore, CW could suppress the activation of renin-angiotensin-aldosterone system by decreasing serum antidiuretic hormone, angiotensin II, and aldosterone levels, and significantly increasing the serum atriopeptin level. CW treatment significantly reduced the mRNA expressions and protein levels of aquaporin 1 (AQP1), AQP2, and AQP 3. This report provided basic data for explaining the natural tropical beverage of CW as an alternative diuretic agent.

Attenuation of Postharvest Browning in Rambutan Fruit by Melatonin Is Associated With Inhibition of Phenolics Oxidation and Reinforcement of Antioxidative Process.

Rambutan is a famous tropical fruit with a unique flavor and considerable economic value. However, the high vulnerability to postharvest browning leads to a short shelf life of rambutan fruit. Melatonin (MT) is an excellent bioactive molecule that possesses the potential to improve the storability of the harvested crops. In this study, the physiological mechanism of exogenous MT in affecting pericarp browning and senescence of postharvest rambutan fruit was investigated. Experimental results showed that the application of MT at 0.125 mmol L-1 appreciably retarded the advancement of pericarp browning and color parameters (L*, a*, and b*). MT treatment inhibited the increase in membrane relative electrolytes leakage (REL) while lowering the accumulation of reactive oxygen species (ROS) (■O2 - and H2O2) and malonaldehyde (MDA). Reduced phenolics oxidation, as indicated by higher contents of total phenolics, flavonoids, and anthocyanins along with fewer activities of peroxidase (POD) and polyphenol oxidase (PPO), was detected in MT fruit compared with control fruit. MT treatment maintained the cellular redox state by inducing antioxidant enzyme activity and reinforcing the ascorbate-glutathione (AsA-GSH) cycle. Furthermore, the ultrastructural observation revealed that the spoilage of cellular and subcellular structures was milder in MT fruit than that in control fruit. The results suggest that MT could ameliorate the browning and senescence of rambutan fruit by inhibiting phenolic oxidation and enhancing the antioxidative process.

Abnormal chilling injury of postharvest papaya is associated with the antioxidant response.

Generally, the lower the temperature and/or the longer the duration of low temperature, the more serious chilling injury (CI) symptom appears in fruit. However, our previous study showed that the higher storage temperature (6°C) resulted in a more serious CI in papaya fruit compared to that stored at 1°C, which could be viewed as an abnormal CI behavior. This study investigated the antioxidant responses that existed in abnormal CI behavior of papaya fruit. Compared to 6°C, antioxidant enzyme activities of papaya fruit which was stored at 1°C were maintained at a higher level while the circulatory metabolism of the ascorbate-glutathione cycle (AsA-GSH) was more vigorous in papaya fruit, as indicated by higher superoxide dismutase (SOD), peroxidase (POD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), and monodehydroascorbate reductase (MDHAR) activities and higher AsA and GSH levels, which could reduce the superoxide anion (·O2 - ) production rate and the hydrogen peroxide (H2 O2 ) content. Suppressed reactive oxygen species (ROS) generation in papaya fruit at 1°C resulted in reduced membrane permeability and malondialdehyde (MDA) accumulation when compared to that at 6°C, thus the development of CI was restricted during storage at 1°C. This study deepened the understanding of differential antioxidant responses during cold storage at 1°C and 6°C in papaya fruit and provided a theoretical basis for further study on the mechanism of the abnormal CI behavior in papaya fruit. PRACTICAL APPLICATIONS: Low-temperature storage is one of the most effective methods to preserve fruit and vegetable products. While, inappropriate low temperature could induce CI, and the damage caused by CI is often more serious than estimated. Therefore, it is necessary to study the physiological and biochemical characteristics of different postharvest fruits and vegetables to prolong storage period, improve storage quality and reduce the loss of products. This study analyzed the antioxidant reaction in abnormal CI behavior of papaya, which could contribute to the further study on the mechanism of CI in papaya fruit and provide theoretical basis for the development of preservation technology of papaya fruit.

Enzymatic browning in relation to permeation of oxygen into the kernel of postharvest areca nut under different storage temperatures.

Previous study indicates that kernel of areca nut is susceptible to enzymatic browning caused by phenolic oxidation, which involves the ingression of oxygen into interior tissue. However, the reason for permeation of oxygen into the interior of areca nut and its possible influencing factors (e.g., temperatures) are little known. In the present study, we set three storage temperatures (25, 10, and 5°C) and investigated the effects on kernel browning and related physic-biochemical and tissue morphological changes. The results showed that the most severe kernel browning was observed in areca nut stored at 25°C, followed by 5°C. Comparatively, a slower browning development was found in areca nut stored at 10°C. More serious kernel browning at 25 and 5°C might be attributed to increased membrane permeability and aggravated tissue damage in view of morphological observations on pericarp, mesocarp, and kernel shell. Higher lignin content and phenylalanine ammonia-lyase activity were observed in mesocarp of areca nuts stored at 25 and 5°C as compared to 10°C, indicating that mesocarp lignification could facilitate the permeability of oxygen. Furthermore, the data showed that storage at 25 and 5°C induced the higher polyphenol oxidase activity while accelerating the decline in total phenolic content in areca nut kernel, which could contribute to higher occurrence of enzymatic browning reaction compared to that at 10°C. These results suggest that natural senescence at 25°C and severe chilling stress at 5°C could be influencing factors triggering the permeation of oxygen, leading to internal kernel browning in areca nut.

Study on the browning mechanism of betel nut (Betel catechu L.) kernel.

Taking betel nut (Betel catechu L.) kernel as raw materials, to analyze the browning mechanism of betel nut kernel. First, we extract and separate the phenolic substances and polyphenol oxidase (PPO) from the betel nut kernel and then find out how O2 penetrates into the kernel, study the above 3 key factors of enzymatic browning so as to prove the possibility of enzymatic browning, and further study the browning products to clarify the mechanism of browning of betel nut kernel during storage process. The results showed that 11 kinds of phenolic compounds were isolated and identified from the betel nut kernel by liquid chromatography-mass spectrometry, among which chlorogenic acid was the highest, followed by dopamine and L-epicatechin, and other contents were relatively low. Meanwhile, PPO was also separated from the betel nut kernel by DEAE-Sepharose Fast Flow and Phenyl-Sepharose 6 Fast Flow column chromatography. On this basis, scanning electron microscopy showed that the damage of the betel nut tissue was aggravated with the prolonged storage time, the wax was gradually decomposed, and the stratum corneum of the peel is destroyed in a honeycomb-shaped; the lignification of the flesh was aggravated, and the interstitial space was increased; and the crack of the kernel membrane was also enlarged. These changes of structure contribute to increase gas exchange within and outside the organization, including the entry of O2. Finally, the oxidation products generated from simulated reaction of chlorogenic acid, dopamine, and epicatechin with purified PPO under aerobic conditions in vitro were compared with the products extracted from naturally brown betel nut, and the same absorption spectra were found. Therefore, it indicates that the browning of betel nut kernel is an enzymatic browning caused by the reaction of phenolic substrates were oxidized by PPO.

Optimized ultrasonic-assisted extraction of papaya seed oil from Hainan/Eksotika variety.

Hainan/Eksotika papaya is a popular cultivated plant in Hainan Island, China. Papaya seed oil (PSO) contains functional compounds with good antioxidant activity, especially monounsaturated fatty acids. In this work, the ultrasound-assisted extraction (UAE) of PSO was optimized using response surface methodology. It was found that the optimal extraction performance was realized when the elevated time was set to 20 min, the ultrasound power was set to 250 W, and the n-hexane-to-sample ratio was set to 16:1 (v/w). The highest yield of PSO (32.27%) was obtained under the optimal conditions, and PSO showed good oxidative stability. Differential scanning calorimetry analysis showed that the melting point of Hainan/Eksotika PSO was low, while its crystallization temperature was high. FTIR and NMR were used to analyze the chemical structure of PSO, which also proved that PSO possessed good stability without oxidative degradation. In addition, scanning electron micrograph was employed to investigate the change in seed microscopic structure. The results showed UAE caused serious structural damage of sample cell membranes and walls, which help oil access to the solvent with a high extraction ratio. The results indicated that UAE is an efficient environmental-friendly, and promising technique could be applied to produce PSO or other edible oil with a better health-beneficial value in food industry.

Application of steam explosion in oil extraction of camellia seed (Camellia oleifera Abel.) and evaluation of its physicochemical properties, fatty acid, and antioxidant activities.

This study evaluated the physicochemical properties of oils extracted from steam-exploded camellia seed (Camellia oleifera Abel.). Steam pressure, resident time, fatty acid composition, total phenolics, tocopherol, squalene, and sterol contents, and volatile compounds were determined. 1H NMR and FTIR spectra were performed for the structure of camellia seed oil. This study has found the highest yield of oil was 86.56% and was obtained when steam explosion pretreatment was at 1.6 MPa 30 s. Oil extracted by steam explosion pretreatment exhibited favorable physicochemical properties and stronger antioxidant activities compared to untreated oil. The compositions of fatty acid were similar between treated and untreated camellia seed oil. According to the 1H NMR and FTIR analyses, the functional groups of the oils were not significantly affected by the steam explosion pretreatment. Furans such as 2-pentyl-furan, 2-furanmethanol, and 3-methyl-furan were produced from stream-exploded camellia seed. Scanning electron microscopy revealed that steam explosion pretreatment efficiently promoted the release of oil by destroying the cell structure of camellia seed. Therefore, steam explosion can be an effective method for the camellia seed oil extraction.

Effect of glycine betaine on chilling injury in relation to energy metabolism in papaya fruit during cold storage.

"Zhongbai" papaya fruit were treated with 15 mmol/L glycine betaine (GB) and then refrigerated at 6°C for 40 days to study the influence of GB on chilling injury (CI) and possible mechanism associated with energy metabolism. The results exhibited that GB treatment remarkably reduced the CI severity as indicated by lower CI index during storage. GB treatment lowered electrolyte leakage and malondialdehyde content, which accounted for maintenance of membrane integrity and reduced lipid peroxidation. Moreover, GB treatment improved the energy status as revealed by increased adenosine triphosphate (ATP) level, energy charge, and activities of energy metabolism-related enzymes including mitochondrial membrane H+-adenosine triphosphatase (H+-ATPase) and Ca2+-adenosine triphosphatase (Ca2+-ATPase), succinate dehydrogenase (SDH), and cytochrome C oxidase (CCO). The results indicate that enhanced chilling tolerance in papaya fruit by GB treatment during cold storage might be ascribed to improved energy status in association with increased activities of energy metabolism-related enzymes.

Hydroxysafflor yellow A ameliorates lipopolysaccharide-induced acute lung injury in mice via modulating toll-like receptor 4 signaling pathways.

Hydroxysafflor yellow A (HSYA) is a main bio-active compound important of a traditional Chinese medicine named Carthamus tinctorius L. and has been shown to possess various effects, especially anti-inflammatory benefits and potential protections against acute lung injury (ALI) in previous studies. Therefore, in this present study, we aimed to evaluating effects of HSYA on lipopolysaccharide (LPS)-induced ALI in mice. ALI was induced by intratracheal instillation of LPS into lung, and dexamethasone was used as a positive control. Results demonstrated that HSYA abated LPS-induced pathological change and attenuated lung vascular permeability and edema. HSYA down-regulated both the ability of myeloperoxidase (MPO) in lung tissues and levels of inflammatory mediators including tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-6 and IFN(interferon)-ß in serum. Moreover, HSYA prevented toll-like receptor 4 (TLR4), myeloid differentiation factor 88 (MyD88) and TIR-domain-containing adapter-inducing interferon-ß (TRIF) protein up-expressions. In addition, the activations of mitogen-activated protein kinases including p38, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK) were blocked by HSYA. And also, the phosphorylations of interferon regulatory factor 3 (IRF3), translocation of nuclear factor kappa B (NF-κB)/p65 and inhibitory kappa B (IκB)-α were inhibited by HSYA. In conclusion, HSYA attenuated inflammatory response in ALI mice through inhibition of TLR 4-dependent signaling pathways.