Hypolipidemic effects and absorption of citrus polymethoxylated flavones in hamsters with diet-induced hypercholesterolemia

Comprehensive identifying flavonoids in Citri Reticulatae Pericarpium using a novel strategy based on precursor ions locked and targeted MS/MS analysis

Citri Reticulatae Pericarpium is a traditional Chinese medicine with extremely high health benefits as well as clinical value. In vivo and in vitro tests have proved that its main active secondary metabolites are flavonoids. However, they have not been comprehensively analyzed up to now mainly due to lack of suitable analysis method. To solve this problem, a novel strategy based on precursor ions locked and targeted MS/MS analysis was proposed. Firstly, the database of the flavonoids previously isolated from Citri Reticulatae Pericarpium was established to obtain the characteristics of their precursor ions. Secondly, after performing the full MS scan of the extract, all compounds in the total ion chromatogram were extracted by Compound Discoverer software. Thirdly, the precursor ions of the flavonoids were locked from the extracted compounds according to their characteristics, forming a precursor ions list. Finally, the precursor ions in the constructed list were performed targeted MS/MS analysis for structures characterization. As a result, total 187 flavonoids were successfully identified, and except for flavones, flavonols as well as dihydroflavones, some chalcones were also characterized from Citri Reticulatae Pericarpium for the first time.

An Update on the Potential of Tangeretin in the Management of Neuroinflammation-Mediated Neurodegenerative Disorders

Neuroinflammation is the major cause of neurodegenerative disorders such as Alzheimer's and Parkinson's disease. Currently available drugs present relatively low efficacy and are not capable of modifying the course of the disease or delaying its progression. Identifying well-tolerated and brain-penetrant agents of plant origin could fulfil the pressing need for novel treatment techniques for neuroinflammation. Attention has been drawn to a large family of flavonoids in citrus fruits, which may function as strong nutraceuticals in slowing down the development and progression of neuroinflammation. This review is aimed at elucidating and summarizing the effects of the flavonoid tangeretin (TAN) in the management of neuroinflammation-mediated neurodegenerative disorders. A literature survey was performed using various resources, including ScienceDirect, PubMed, Google Scholar, Springer, and Web of Science. The data revealed that TAN exhibited immense neuroprotective effects in addition to its anti-oxidant, anti-diabetic, and peroxisome proliferator-activated receptor-γ agonistic effects. The effects of TAN are mainly mediated through the inhibition of oxidative and inflammatory pathways via regulating multiple signaling pathways, including c-Jun N-terminal kinase, phosphoinositide 3-kinase, mitogen-activated protein kinase, nuclear factor erythroid-2-related factor 2, extracellular-signal-regulated kinase, and CRE-dependent transcription. In conclusion, the citrus flavonoid TAN has the potential to prevent neuronal death mediated by neuroinflammatory pathways and can be developed as an auxiliary therapeutic agent in the management of neurodegenerative disorders.

Bioactives from citrus food waste: types, extraction technologies and application

The Citrus fruits belong to the category where the groups of fruits are recognized to be an admirable repository of bioactive elements and phytochemical constituents, with strong biological potentials. The prominent use of Citrus fruits for nutrition as well as food processing has led to the release of a large amount of waste into the environment and surrounding, and it simultaneously burdens the nature and existence of many organisms including the human population. In order to rectify such consequences, the reuse of food waste from citrus for various advantageous effects. In this regard, the first part of the article primarily focussed on the various strategies available for the extraction of chemical elements from citrus waste and the remaining strand of the article focussed on the various bioactive compounds with special reference to their pharmacological as well as the medicinal benefits and future prospects.

Graphical abstract

Inhibitory effect of trans-tiliroside on very low-density lipoprotein secretion in HepG2 cells and mouse liver

An acylated flavonol glycoside, trans-tiliroside (1), is found in certain parts of different herbs, including the seeds of Rosa canina (Rosaceae). Previous studies on compound 1 have focused on triglyceride (TG) metabolism, including its anti-obesity and intracellular TG reduction effects. In the present study, the effects of compound 1 on cholesterol (CHO) metabolism were investigated using human hepatocellular carcinoma-derived HepG2 cells and mice. Compound 1 decreased CHO secretion in HepG2 cells, which was enhanced by mevalonate in a concentration-dependent manner and decreased the secretion of apoprotein B (apoB)-100, a marker of very low-density lipoprotein (VLDL). Compound 1 also inhibited the activity of microsomal triglyceride transfer proteins, which mediate VLDL formation from cholesterol and triglycerides in the liver. In vivo, compound 1 inhibited the accumulation of Triton WR-1339-induced TG in the blood of fasted mice and maintained low levels of apoB-100. These results suggest that compound 1 inhibits the secretion of CHO as VLDL from the liver and has the potential for use for the prevention of dyslipidemia.

Optimized Sugar-Free Citrus Lemon Juice Fermentation Efficiency and the Lipid-Lowering Effects of the Fermented Juice

Aging and obesity make humans more prone to cardiovascular and metabolic syndrome diseases, leading to several serious health conditions, including hyperlipidemia, high blood pressure, and sleep disturbance. This study aimed to explore the hypolipidemic effect of fermented citrus lemon juice using a hyperlipidemic hamster model. The sugar-free lemon juice's fermentation was optimized, and the characteristics of fresh and fermented lemon juice (FLJ) were evaluated and compared, which contained polyphenols and superoxide dismutase-like activity. Results showed that the absorption and utilization efficiency of FLJ was higher compared with the unfermented lemon juice. This study's prefermentation efficiency evaluation found that 21-30 days of bacterial DMS32004 and DMS32005 fermentation of fresh lemon juice provided the best fermentation benefits, and 21-day FLJ was applied as a remedy after the efficiency compassion. After six weeks of feeding, the total cholesterol (TC) and triglyceride (TG) values in the blood and liver of the FLJ treatment groups were decreased compared with the high-fat diet (HFD) group. In addition, the blood low-density lipoprotein cholesterol (LDL-C) levels were significantly reduced in the FLJ treatment groups compared with the HFD group. In contrast, the blood high-density lipoprotein (HDL-C) to LDL-C ratio increased considerably in the FLJ treatment groups, and the total to HDL ratio was significantly lower than in the HFD group. Compared with the HFD group, the TC content in the FLJ treatment groups' feces increased significantly. This study demonstrated that the sugar-free fermentation method and fermentation cycle management provided FLJ with the potential to regulate blood lipids. Further research and verification will be carried out to isolate specific substances from the FLJ and identify their mechanisms of action.

The Hexane Extract of Citrus sphaerocarpa Ameliorates Visceral Adiposity by Regulating the PI3K/AKT/FoxO1 and AMPK/ACC Signaling Pathways in High-Fat-Diet-Induced Obese Mice

Obesity is an emerging global health issue with an increasing risk of disease linked to lifestyle choices. Previously, we reported that the hexane extract of Citrus sphaerocarpa (CSHE) suppressed lipid accumulation in differentiated 3T3-L1 adipocytes. In this study, we conducted in vivo experiments to assess whether CSHE suppressed obesity in zebrafish and mouse models. We administered 10 and 20 μg/mL CSHE to obese zebrafish juveniles. CSHE significantly inhibited visceral fat accumulation compared to untreated obese fish. Moreover, the oral administration (100 μg/g body weight/day) of CSHE to high-fat-diet-induced obese mice significantly reduced their body weight, visceral fat volume, and hepatic lipid accumulation. The expression analyses of key regulatory genes involved in lipid metabolism revealed that CSHE upregulated the mRNA expression of lipolysis-related genes in the mouse liver (Pparα and Acox1) and downregulated lipogenesis-related gene (Fasn) expression in epididymal white adipose tissue (eWAT). Fluorescence immunostaining demonstrated the CSHE-mediated enhanced phosphorylation of AKT, AMPK, ACC, and FoxO1, which are crucial factors regulating adipogenesis. CSHE-treated differentiated 3T3L1 adipocytes also exhibited an increased phosphorylation of ACC. Therefore, we propose that CSHE suppresses adipogenesis and enhances lipolysis by regulating the PI3K/AKT/FoxO1 and AMPK/ACC signaling pathways. These findings suggested that CSHE is a promising novel preventive and therapeutic agent for managing obesity.

Natural products in non-alcoholic fatty liver disease (NAFLD): Novel lead discovery for drug development

With changing lifestyles, non-alcoholic fatty liver disease (NAFLD) has become the most prevalent liver disease worldwide. A substantial increase in the incidence, mortality, and associated burden of NAFLD-related advanced liver disease is expected. Currently, the initial diagnosis of NAFLD is still based on ultrasound and there is no approved treatment method. Lipid-lowering drugs, vitamin supplementation, and lifestyle improvement treatments are commonly used in clinical practice. However, most lipid-lowering drugs can produce poor patient compliance and specific adverse effects. Therefore, the exploration of bio-diagnostic markers and active lead compounds for the development of innovative drugs is urgently needed. More and more studies have reported the anti-NAFLD effects and mechanisms of natural products (NPs), which have become an important source for new drug development to treat NAFLD due to their high activity and low side effects. At present, berberine and silymarin have been approved by the US FDA to enter clinical phase IV studies, demonstrating the potential of NPs against NAFLD. Studies have found that the regulation of lipid metabolism, insulin resistance, oxidative stress, and inflammation-related pathways may play important roles in the process. With the continuous updating of technical means and scientific theories, in-depth research on the targets and mechanisms of NPs against NAFLD can provide new possibilities to find bio-diagnostic markers and innovative drugs. As we know, FXR agonists, PPARα agonists, and dual CCR2/5 inhibitors are gradually coming on stage for the treatment of NAFLD. Whether NPs can exert anti-NAFLD effects by regulating these targets or some unknown targets remains to be further studied. Therefore, the study reviewed the potential anti-NAFLD NPs and their targets. Some works on the discovery of new targets and the docking of active lead compounds were also discussed. It is hoped that this review can provide some reference values for the development of non-invasive diagnostic markers and new drugs against NAFLD in the clinic.

Tangeretin and 4'-demethyltangeretin prevent damage to mouse hepatocytes from oxidative stress by activating the Nrf2-related antioxidant pathway via an epigenetic mechanism

Polymethoxyflavones (PMFs) in citrus fruits have a variety of biological activities, including antioxidant, anti-inflammatory, anticancer, and anti-atherosclerotic effects. The liver is the major detoxifying organ of the human body; however, factors such as acetaminophen (APAP) overdose may increase oxidative stress in liver cells and lead to severe liver failure. In this study we examined the effects of tangeretin (TAN), a common citrus PMF, and its metabolite 4'-demethyltangeretin (4'-OH-TAN) on activation of the Nrf2 antioxidant system in mouse AML-12 hepatocytes through regulation by epigenetic mechanisms. The ability of TAN and 4'-OH-TAN to inhibit APAP-induced hepatotoxicity was also evaluated. The results showed that TAN and 4'-OH-TAN significantly increased the mRNA and protein levels of Nrf2 and Nrf2-mediated antioxidant and detoxifying enzymes (UGT1A, HO-1, and NQO1) in AML-12 cells. TAN and 4'-OH-TAN also suppressed protein expression of histone deacetylases (HDACs) and DNA methyltransferases (DMNTs) and reduced DNA methylation of the nrf2 promoter. Furthermore, TAN and 4'-OH-TAN prevented APAP-induced injury and inhibited APAP-induced ROS generation in AML-12 cells. Based on these results, we conclude that TAN and 4'-OH-TAN may increase the antioxidant capacity of liver cells by regulating epigenetic alteration to activate the Nrf2-related antioxidant system, thereby preventing liver cells from being damaged by APAP-induced oxidative stress.

Seven-day Oral Intake of Orthosiphon stamineus Leaves Infusion Exerts Antiadhesive Ex Vivo Activity Against Uropathogenic E. coli in Urine Samples

Orthosiphon stamineus leaves (Java tea) extract is traditionally used for the treatment of urinary tract infections. According to recent in vitro data, animal infection studies, and transcriptomic investigations, polymethoxylated flavones from Java tea exert antiadhesive activity against uropathogenic Escherichia coli (UPEC). This antiadhesive activity has been shown to reduce bladder and kidney lesion in a mice infection model. As no data on the antivirulent activity of Java tea intake on humans are available, a biomedical study was performed on 20 healthy volunteers who self-administered Orthosiphon infusion (4 × 3 g per day, orally) for 7 days. The herbal material used for the study conformed to the specification of the European Pharmacopoeia, and ultra high-performance liquid chromatography (UHPLC) of the infusion showed rosmarinic acid, caffeic acid, and cichoric acid to be the main compounds aside from polymethoxylated flavones. Rosmarinic acid was quantified in the tea preparations with 243 ± 22 µg/mL, indicating sufficient reproducibility of the preparation of the infusion. Urine samples were obtained during the biomedical study on day 1 (control urine, prior to Java tea intake), 3, 6 and 8. Antiadhesive activity of the urine samples was quantified by flowcytometric assay using pre-treated UPEC NU14 and human T24 bladder cells. Pooled urine samples indicated significant inhibition of bacterial adhesion on day 3, 6 and 8. The urine samples had no influence on the invasion of UPEC into host cells. Bacterial proliferation was slightly reduced after 24 h incubation with the urine samples. Gene expression analysis (qPCR) revealed strong induction of fitness and motility gene fliC and downregulation of hemin uptake system chuT. These data correlate with previously reported datasets from in vitro transcriptomic analysis. Increased bacterial motility was monitored using a motility assay in soft agar with UPEC UTI89. The intake of Java tea had no effect on the concentration of Tamm-Horsfall Protein in the urine samples. The present study explains the antiadhesive and anti-infective effect of the plant extract by triggering UPEC from a sessile lifestyle into a motile bacterial form, with reduced adhesive capacity.

A Scientometric Study to a Critical Review on Promising Anticancer and Neuroprotective Compounds: Citrus Flavonoids

Flavonoids derived from citrus plants are favored by phytomedicinal researchers due to their wide range of biological activities, and relevant studies have been sustained for 67 years (since the first paper published in 1955). In terms of a scientometric and critical review, the scientometrics of related papers, chemical structures, and pharmacological action of citrus flavonoids were comprehensively summarized. The modern pharmacological effects of citrus flavonoids are primarily focused on their anticancer activities (such as breast cancer, gastric cancer, lung cancer, and liver cancer), neuroprotective effects (such as anti-Alzheimer’s disease, Parkinson’s disease), and metabolic diseases. Furthermore, the therapeutic mechanism of cancers (including inducing apoptosis, inhibiting cell proliferation, and inhibiting cancer metastasis), neuroprotective effects (including antioxidant and anti-inflammatory), and metabolic diseases (such as non-alcoholic fatty liver disease, type 2 diabetes mellitus) were summarized and discussed. We anticipate that this review could provide an essential reference for anti-cancer and neuroprotective research of citrus flavonoids and provide researchers with a comprehensive understanding of citrus flavonoids.

Orange juice intake and lipid profile: a systematic review and meta-analysis of randomised controlled trials

Dyslipidaemia is a metabolic anomaly which has been related to numerous morbidities. Orange juice (OJ) is a popular flavonoid-rich drink consumed worldwide. Due to the existing controversies regarding its impact on blood lipids, we decided to investigate the impact of OJ supplementation on lipid profile parameters. Major scientific databases (Cochrane library, Scopus, PubMed and Embase) were searched. Pooled effects sizes were reported as weighted mean difference (WMD) and 95 % confidence intervals (CIs). Out of 6334 articles retrieved by the initial search, 9 articles met our inclusion criteria. Overall, supplementation with OJ did not exert any significant effects on blood levels of TG (WMD −1·53 mg/dl, 95 % CI −6·39, 3·32, P = 0·536), TC (WMD −5·91 mg/dl, 95 % CI −13·26, 1·43, P = 0·114) or HDL-C (WMD 0·61 mg/ dl, 95 % CI −0·61, 1·82, P = 0·333). OJ consumption did reduce LDL-C levels significantly (WMD −8·35 mg/dl, 95 % CI −15·43, −1·26, P = 0·021). Overall, we showed that the consumption of OJ may not be beneficial in improving serum levels of TG, TC or HDL-C. Contrarily, we showed that daily intake of OJ, especially more than 500 ml/d, might be effective in reducing LDL-C levels. In the light of the existing inconsistencies, we propose that further high-quality interventions be conducted in order to make a solid conclusion.

Anti-Inflammatory Property of 5-Demethylnobiletin (5-Hydroxy-6, 7, 8, 3', 4'-pentamethoxyflavone) and Its Metabolites in Lipopolysaccharide (LPS)-Induced RAW 264.7 Cells

Hydroxylated polymethoxyflavones (PMFs) are a unique class of flavonoid compounds mainly found in citrus plants. We investigated the anti-inflammatory effects of one major 5-hydroxy PMF, namely 5-demethylnobiletin (5DN) and its metabolites 5, 3'-didemethylnobiletin (M1), 5, 4'-didemethylnobiletin (M2), and 5, 3', 4'-tridemethylnobiletin (M3) in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. The results showed that M2 and M3 produced stronger inhibitory effects on the production of nitric oxide (NO) than their parent compound at non-cytotoxic concentrations. Western blotting and real-time PCR analyses demonstrated that M2 and M3 significantly decreased iNOS and COX-2 gene expression. The results also showed that M1 and M3 induced heme oxygenase-1(HO-1) gene expression. Overall, our results demonstrated that metabolites of 5DN significantly inhibited LPS-induced inflammation in RAW 264.7 macrophage cells and generally possessed more potent anti-inflammatory activity than the parent compound, 5DN.

Free and Bound Phenolic Compounds Present in Orange Juice By-Product Powder and Their Contribution to Antioxidant Activity

Interest in fruit/vegetable consumption is not always linked to a particular diet but rather derives from their high antioxidant activity (AOA), with potential health benefits provided, in part, by polyphenols. Although phenols can be found in free form (FP) or bound to plant tissues (BP), the experimental methodology most frequently used for the quantification of total phenols (TP) is based on the extraction of a portion of FP, which may justify the lack of correlation often found between them and AOA. In this context, four successive extractions were performed to obtain FP and BP of powdered orange juice by-product, and their contribution to the AOA was studied. The first extract (MeOH, 30 °C) can be assumed to be one of the conventional methods for the quantification of TP. Re-extraction with MeOH (60 °C) afforded the FP. Two subsequent basic and acidic extractions yielded the BP. Although the FPs were the most abundant, the AOA (DPPH method) of the last fraction of BP was of the same order found in the first fraction of FP. This highlights the interest in extracting the BP from the by-product of orange juice if its antioxidant capacity is to be exploited.

Presence and risks of polycyclic aromatic hydrocarbons, dioxins and dioxin-like PCBs in dietary plant supplements as elucidated by a combined DR CALUX® bioassay and GC-HRMS based approach

Plant-based dietary supplements may contain undesirable contaminants such as polycyclic aromatic hydrocarbons, dioxins and dioxin-like polychlorinated biphenyls (dl-PCBs) due to the sources of raw materials or processing methods used. The presence of these contaminants in a series of herbal supplements sold on the Ghanaian market for improving sexual performance was examined using the DR CALUX^® bioassay in combination with GC-HRMS analysis. Overall, cell responses at 4 and 48 h exposure to extracts prepared without an acid-silica clean-up were relatively higher than the responses obtained from extracts prepared with an acid-silica clean-up. This indicated that the 40 supplements contained only low levels of stable aryl hydrocarbon receptor (AhR) agonists like polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) and dl-PCBs, while some contained substantial amounts of less stable AhR-agonists. Ten supplements selected for confirmation with GC-HRMS analysis contained PCDD/Fs and dl-PCBs at levels ranging from 0.01 to 0.19 pg toxic equivalent (TEQ)/g only, while the level of the sum of 4 polycyclic aromatic hydrocarbons (Σ4PAHs) representing less stable AhR agonists, ranged from not detected (ND) to 25.5 ng/g. These concentrations were in line with the responses observed in the DR CALUX^® bioassay. The concentration of PCDD/Fs and dl-PCBs corresponded to estimated daily intakes (EDIs) ranging from 0.01 to 1.20 pg TEQ/day, or 0.001 to 0.12 pg TEQ/kg bw/week for a 70 kg bw consumer, which was below the established tolerable weekly intake (TWI) of 2 pg TEQ/kg bw/week, thus indicating low concern for consumers' health. Similarly, the EDIs based on the detected Σ4PAHs in supplements ranged from 7.2 to 111 ng/day, or 0.1 to 1.6 ng/kg bw/day, which corresponded to MOE values above 10,000, indicating a low health concern.

Review of phytochemical and nutritional characteristics and food applications of Citrus L. fruits

Since the dietary regimen rich in fruits is being widely recognized and encouraged, Citrus L. fruits have been growing in popularity worldwide due to their high amounts of health-promoting phytonutrients and bioactive compounds, such as flavonoids, phenolic acids, vitamins, carotenoids, pectins, and fatty acids. The diverse physicochemical properties and multiple utilization of citrus fruits in food industry are associated with their unique chemical compositions. Throughout the world, citrus has been used for producing various value-added and nutritionally enhanced products, including juices, wines, jams, canned citrus, and dried citrus. However, the current studies regarding the phytochemical and nutritional characteristics and food applications of citrus are scattered. This review systematically summarizes the existing bibliography on the chemical characteristics, functional and nutraceutical benefits, processing, and potential applications of citrus. A thorough understanding of this information may provide scientific guidance for better utilizing citrus as a functional fruit and benefit the extension of citrus value chain.

Influence of Tangeretin on the Exponential Regression of Inflammation and Oxidative Stress in Streptozotocin-Induced Diabetic Nephropathy

Diabetes is an amalgamation of metabolic disorders marked by hyperglycemia. Over time diabetes brings up several other complications with it like cardiovascular disease, retinopathy, neuropathy, and nephropathy. among which diabetic nephropathy (DN) is the one we are concerned about in the present study. Diabetes management requires following a healthy lifestyle with proper medication. Most of the anti-diabetic drugs available at present come with adverse side effects. Nature has provided us with several components that are anti-diabetic in nature which has fewer or no side effects and tangeretin is one among them. Tangeretin is a natural flavonoid abundantly present in orange peel and tangerines. Our study is designed to evaluate tangeretin, as an anti-diabetic medication especially for patients suffering from diabetic nephropathy. The procured healthy rats were first divided into four groups: the group I was maintained as healthy control and the others were subjected to the induction of diabetes by i.p. injection of streptozotocin (STZ) at the concentration of 55mg/kg b.wt .Then, the diabetic rats were further divided into three groups: group II was used as the diabetic control rats and the group III and group IV were administered with tangeretin (25mg/kg b.wt) and positive control drug metformin (150mg/kg b.wt) for 8 weeks. The body weight, blood glucose, and serum insulin levels were estimated at week 0 and week 8. Reactive oxygen species (ROS) inhibitory effect, antioxidant, antilipidemic, nephroprotective, and anti-inflammatory effects of tangeretin on the diabetic-induced rats were evaluated at the end of week 8 in addition to the histopathological assessment of the sections of the kidneys of the experimental rats. All the test results concluded that tangeretin was able to significantly decelerate the progression of DN in STZ-induced diabetic rats.

Changes in Serum Blood Parameters in Farmed Rainbow Trout (Oncorhynchus mykiss) Fed with Diets Supplemented with Waste Derived from Supercritical Fluid Extraction of Sweet Basil (Ocimum basilicum)

The antimicrobial and immunostimulant proprieties of aromatic plant extracts have been widely described, but their effects on serum blood biochemistry in fish have not. For this study, we assessed the changes in serum blood biochemical parameters in rainbow trout fed with a fish diet supplemented with a basil supercritical extract (F1-BEO). Our hypothesis was that treatment and time would be associated with changes in 10 serum blood biochemical parameters. F1-BEO was added to a commercial feed (0.5, 1, 2, 3% w/w). The fish were fed for 30 days, and the blood samples were collected at 2 time points (15 and 30 days). A two-way ANOVA showed a significant effect of treatment, time, and interaction treatment × time on creatinine, urea, total protein, albumin, magnesium, and phosphorus (p < 0.05), a significant effect of both time and interaction treatment × time on cholesterol (CHOL), glutamic oxaloacetic transaminase (GOT), and glutamic pyruvic transaminase (GPT) levels, and a significant effect of time on triglycerides (p < 0.05). While changes in several of the parameters were observed, the levels remained within the normal range for rainbow trout. Notably, after 30 days there was a significant decrease in CHOL in fish treated with 0.5% and 1% w/w F1-BEO (p < 0.05). The statistically non-significant increase in GOT and GPT in the fish fed with F1-BEO up to 3% w/w indicated a positive effect of basil on liver health. Our findings suggest a potential use for basil extracts (for example., F1-BEO) in fish feed to reduce antibiotic use and improve fish welfare.

Efficient sterilization system combining flavonoids and hyaluronic acid with metal organic frameworks as carrier

Bacterial infections can cause many human diseases, which are closely related to people's health. Nowadays, antibiotics are mainly used to treat bacterial infections, but the widespread use of antibiotics can also lead to bacterial resistance. Therefore, effective treatment of bacterial infections is an urgent problem to be solved. In this article, a multifunctional therapeutic material with antibacterial properties was designed and synthesized. First, the porous media material ZIF-8 was synthesized, and applied to load hesperidin. When the load is completed, a layer of hyaluronic acid (HA) is uniformly wrapped on surface of the material. Such materials have high stability and high drug-carrying capacity, and can be slowly released in vivo. The HA coated on surface can also promote penetration of active ingredients into cells and give full play to antibacterial ability. Results of in vitro and in vivo antibacterial tests show that synergy between the materials enhances antibacterial activity which is related to dose. The material achieves high-efficiency antibacterial effects by increasing the permeability of cell membranes and destroying the integrity of bacteria. At same time, the material does not show obvious side effects. Therefore, the material seems to be a promising antibacterial agent with good biocompatibility and strong antibacterial activity.

Fruit peel bioactives, valorisation into nanoparticles and potential applications: A review

Nanotechnology is a rapidly growing field with profound applications in different domains, particularly in food science and technology. Nanoparticles (NPs) synthesis, an integral part of nanotechnology-based applications, is broadly classified into chemical, physical and biosynthesis methods. Chemically sensitive and energy-intensive procedures employed for NPs synthesis are some of the limits of traditional chemical approaches. Recent research has focused on developing easy, nontoxic, cost-effective, and environment-friendly NPs synthesis during the last decade. Biosynthesis approaches have been developed to achieve this goal as it is a viable alternative to existing chemical techniques for the synthesis of metallic nanomaterials. Fruit peels contain abundant bioactive compounds including phenols, flavonoids, tannins, triterpenoids, steroids, glycosides, carotenoids, anthocyanins, ellagitannins, vitamin C, and essential oils with substantial health benefits, anti-bacterial and antioxidant properties, generally discarded as byproduct or waste by the fruit processing industry. NPs synthesized using bioactive compounds from fruit peel has futuristic applications for an unrealized market potential for nutraceutical and pharmaceutical delivery. Numerous studies have been conducted for the biosynthesis of metallic NPs such as silver (AgNPs), gold (AuNPs), zinc oxide, iron, copper, palladium and titanium using fruit peel extract, and their synthesis mechanism have been reported in the present review. Additionally, NPs synthesis methods and applications of fruit peel NPs have been discussed.

Citrus Peels as a Source of Bioactive Compounds with Industrial and Therapeutic Applications

Agriculture wastes are considered a good starting point to discover for new drugs all over the world. In this context, Agriculture wastes contain millions of compounds to be screened to find bioactive compounds responsible for the activity to be used in drugs. Citrus agriculture is one of the most important commercial and industrial agricultural activities in the world. The peel waste of Citrus species is a rich source of bioactive compounds such as essential oils, flavones, polyphenols, and pigment. Citrus peel has been widely used in the medicine industry. The waste peel of citrus consider a rich source of pharmacologically active metabolites with antioxidant activities.

Exosome-like nanoparticles from Mulberry bark prevent DSS-induced colitis via the AhR/COPS8 pathway

Bark protects the tree against environmental insults. Here, we analyzed whether this defensive strategy could be utilized to broadly enhance protection against colitis. As a proof of concept, we show that exosome-like nanoparticles (MBELNs) derived from edible mulberry bark confer protection against colitis in a mouse model by promoting heat shock protein family A (Hsp70) member 8 (HSPA8)-mediated activation of the AhR signaling pathway. Activation of this pathway in intestinal epithelial cells leads to the induction of COP9 Constitutive Photomorphogenic Homolog Subunit 8 (COPS8). Utilizing a gut epithelium-specific knockout of COPS8, we demonstrate that COPS8 acts downstream of the AhR pathway and is required for the protective effect of MBELNs by inducing an array of anti-microbial peptides. Our results indicate that MBELNs represent an undescribed mode of inter-kingdom communication in the mammalian intestine through an AhR-COPS8-mediated anti-inflammatory pathway. These data suggest that inflammatory pathways in a microbiota-enriched intestinal environment are regulated by COPS8 and that edible plant-derived ELNs may hold the potential as new agents for the prevention and treatment of gut-related inflammatory disease.

Citrus depressa Hayata Peel Ameliorates Nonalcoholic Fatty Liver and Modulates the Hepatic Drug-metabolizing Enzymes and Transporters in Rats Fed a High-fat Diet

Citrus depressa Hayata is a small, green citrus fruit native to Taiwan and Japan. The citrus peel contains polymethoxylated flavones, including nobiletin and tangeretin, and might have strong antioxidant and...

Tangeretin inhibits fungal ferroptosis to suppress rice blast

Flavonoids are polyphenolic secondary metabolites that function as signaling molecules, allopathic compounds, phytoalexins, detoxifying agents and antimicrobial defensive compounds in plants. Blast caused by the fungus Magnaporthe oryzae is a serious disease affecting rice cultivation. In this study, we revealed that a natural flavonoid, tangeretin, substantially delays the formation of M. oryzae appressoria and blocks the development of blast lesions on rice plants. Our data suggest that tangeretin has antioxidant activity that interferes with conidial cell death/ferroptosis, which is critical for M. oryzae pathogenicity. Tangeretin showed a ferroptosis inhibition efficacy comparable to the well-established liproxstatin-1. Furthermore, overexpression of the NADPH oxidases NOX1 or NOX2 significantly decreased sensitivity toward tangeretin treatment, suggesting Nox-mediated lipid peroxidation as a possible target for tangeretin in regulating redox signaling and ferroptosis in M. oryzae. Our nursery and field tests showed that application of tangeretin can effectively mitigate overall disease symptoms and prevent leaf blast. Our study reveals the plant-derived fungal ferroptosis inhibitor tangeretin as a potential and novel antifungal agrochemical for the sustainable prevention of the devastating blast disease in important cereal crops.

The effects of propolis supplementation on metabolic parameters: A systematic review and meta-analysis of randomized controlled clinical trials

Objective:

Propolis is a sticky, resinous substance produced by honeybees from various plants. Various biological properties of propolis and its extracts have been recognized in previous studies including the antiseptic, anti-inflammatory, antioxidant, antiviral, hepatoprotective, antitumor, antibacterial and antimycotic properties. This study aimed to summarize the effect of propolis on metabolic parameters in human adults using systematic review and meta-analysis.

Materials and Methods:

A comprehensive systematic search was performed in ISI Web of Science, PubMed, Scopus, and Google Scholar up to July 2020 for controlled clinical trials evaluating the impact of propolis on lipid profile and liver enzyme biomarkers. A random effects model was used to calculate the weighted mean difference (WMD) and 95% confidence interval (CI) as the difference between the mean for the intervention and control groups.

Results:

The present meta-analysis included six randomized controlled trials. There was significant reduction in Aspartate Aminotransferase (AST) in comparison to the control groups (WMD=-2.01; 95% CI: -3.93--0.10; p=0.039). However, a non-significant effect was observed in Triglycerides (TG), Total cholesterol (TC), low-density lipoprotein (LDL), High-density lipoprotein (HDL) (WMD=-0.05 mg/dl; 95% CI: -0.27-0.18; p=0.688; WMD=7.08 mg/dl; 95% CI: -37.31-51.46; p=0.755; WMD=-0.94 mg/dl; 95% CI: -6.64-4.77; p=0.747; WMD=3.14 mg/dl; 95% CI: -1.84-8.13; p=0.216, respectively).

Conclusion:

Current meta-analysis revealed that propolis supplementation can reduce AST; nevertheless, there was no significant effect on lipid profile indices and ALT.

Value-Added Metabolites from Agricultural Waste and Application of Green Extraction Techniques

The agricultural sector generates approximately 1300 million tonnes of waste annually, where up to 50% comprising of raw material are discarded without treatment. Economic development and rising living standards have increased the quantity and complexity of waste generated resulting in environmental, health and economic issues. This calls for a greener waste management system such as valorization or recovery of waste into products. For successful implementation, social acceptance is an essential component with involvement of all local stakeholders including community to learn and understand the process and objective of the implementation. The agricultural waste product manufacturing industry is expected to increase with the growing demand for organic food. Thus, proper livestock and crop waste management is vital for environmental protection. It will be essential to successfully convert waste into a sustainable product that is reusable and circulated in the system in line with the green concept of circular economy. This review identifies the commercially produced crops by-product that have been considered for valorization and implemented green extraction for recovery. We highlight the importance of social acceptance and the economic value to agricultural waste recycling. Successful implementation of these technologies will overcome current waste management problems, reduce environmental impacts of landfills, and sustainability issue for farm owners.

The Lipid-Modulating Effect of Tangeretin on the Inhibition of Angiopoietin-like 3 (ANGPTL3) Gene Expression through Regulation of LXRα Activation in Hepatic Cells

The excessive accumulation of TG-rich lipoproteins (TGRLs) in plasma is associated with dyslipidemia and atherosclerotic cardiovascular diseases (ASCVDs). Tangeretin is a bioactive pentamethoxyflavone mainly found in citrus peels, and it has been reported to protect against hyperlipidemia, diabetes, and obesity. The aim of this study was to investigate the lipid-modulating effects and the underlying mechanisms of tangeretin action in hepatic cells. Transcriptome and bioinformatics analyses with the Gene Ontology (GO) database showed that tangeretin significantly regulated a set of 13 differentially expressed genes (DEGs) associated with the regulation of lipoprotein lipase (LPL) activity. Among these DEGs, angiopoietin-like 3 (ANGPTL3), an essential inhibitor of LPL catalytic activity that regulates TGRL metabolism in plasma, was markedly downregulated by tangeretin. We demonstrated that tangeretin significantly inhibited the mRNA expression of ANGPTL3 in HepG2 and Huh-7 cells. Tangeretin treatment of hepatic cells also reduced the levels of both intracellular and secreted ANGPTL3 proteins. Moreover, we found that inhibition of ANGPTL3 production by tangeretin augmented LPL activity. We further demonstrated that the transcriptional activity of the ANGPTL3 promoter was significantly attenuated by tangeretin, and we identified a DNA element located between the −250 and −121 positions that responded to tangeretin. Furthermore, we found that tangeretin did not alter the levels of the nuclear liver X receptor α (LXRα) protein, an essential transcription factor that binds to the tangeretin-responsive element, but it can counteract LXRα-mediated ANGPTL3 transcription. On the basis of molecular docking analysis, tangeretin was predicted to bind to the ligand-binding domain of LXRα, which would result in suppression of LXRα activation. Our findings support the hypothesis that tangeretin exerts a lipid-lowering effect by modulating the LXRα-ANGPTL3-LPL pathway, and thus, it can be used as a potential phytochemical for the prevention or treatment of dyslipidemia.

Citrus peel derived' Poly-Methoxylated Flavones (PMF)

The prevalence of obesity has increased substantially over the last several decades and several environmental factors have accelerated this trend. Poly-methoxy flavones (PMFs) exist abundantly in the peels of citrus, and their biological activities have been broadly examined in recent years. Several studies have examined the effects of PMFs on obesity and its-related diseases. This systematic review conducted to focus on the effect of PMFs on obesity and its related conditions management. The PubMed, Google Scholar, Scopus, and Science Direct databases were searched for relevant studies published before November 2020. Out of 1,615 records screened, 16 studies met the study criteria. The range of dosage of PMFs was varied from 10 to 200 mg/kg (5-26 weeks) and 1-100 μmol (2h-8 days) across selected animal and in vitro studies, respectively. The literature reviewed shows that PMFs modulate several biological processes associated with obesity such as lipid and glucose metabolism, inflammation, energy balance, and oxidative stress by different mechanisms. All of the animal studies showed significant positive effects of PMFs on obesity by reducing body weight (e.g. reduced weight gain by 21.04%), insulin resistance, energy expenditure, inhibiting lipogenesis and reduced blood lipids (e.g. reduced total cholesterol by 23.10%, TG by 44.35% and LDL by 34.41%). The results of the reviewed in vitro studies have revealed that treatment with PMFs significantly inhibits lipid accumulation in adipocytes (e.g. reduced lipid accumulation by 55-60%) and 3T3-L1 pre-adipocyte differentiation as well by decreasing the expression of PPARγ and C/EBPα and also reduces the number and size of fat cells and reduced TG content in adipocytes by 45.67% and 23.10% and 16.08% for nobiletin, tangeretin and hesperetin, respectively. Although current evidence supports the use of PMFs as a complementary treatment in obesity, future research is needed to validate this promising treatment modality.

Antioxidant Activity and Healthy Benefits of Natural Pigments in Fruits: A Review

Natural pigments, including carotenoids, flavonoids and anthocyanidins, determine the attractive color of fruits. These natural pigments are essential secondary metabolites, which play multiple roles in the whole life cycle of plants and are characterized by powerful antioxidant activity. After decades of research and development, multiple benefits of these natural pigments to human health have been explored and recognized and have shown bright application prospects in food, medicine, cosmetics and other industries. In this paper, the research progress of natural fruit pigments in recent years was reviewed, including the structural characteristics and classification, distribution in fruits and analysis methods, biosynthetic process, antioxidant capacity and mechanism, bioaccessibility and bioavailability, and health benefits. Overall, this paper summarizes the recent advances in antioxidant activity and other biological functions of natural fruit pigments, which aims to provide guidance for future research.

The role and mechanism of citrus flavonoids in cardiovascular diseases prevention and treatment

Cardiovascular diseases (CVDs) have been ranked as the leading cause of death in the world, whose global incidence is increasing year by year. Citrus, one of the most popular fruits in the world, is rich in flavonoids. Citrus flavonoids attract special attention due to a variety of biological activities, especially in the prevention and treatment of CVDs. The research progress of citrus flavonoids on CVDs have been constantly updated, but relatively fragmented, which needed to be systematically summarized. Hence, the recent research about citrus flavonoids and CVDs were reviewed, including the types and in vivo processes of citrus flavonoids, epidemiology study and mechanism on prevention and treatment of CVDs by citrus flavonoids. This review would provide a theoretical basis for the citrus flavonoids research and a new idea in the citrus industry development and application.

Extraction Method Affects Contents of Flavonoids and Carotenoids in Huanglongbing-Affected "Valencia" Orange Juice

A previous study using healthy "Valencia" orange fruit found that juicing extraction methods dramatically changed the orange juice (OJ) flavor and phytochemical profiles. The present study was conducted to confirm whether the same changes occur when Huanglongbing (HLB)-affected oranges were used. HLB has extensively spread to most OJ processing regions around the world, substantially deteriorating fruit and juice flavor quality and altering the phytochemical profiles. In this study, the effect of two major juice extractor types, a shear force extractor (SFE) and a reamer extractor (RE), on the juice quality and physiochemical profile was assessed using HLB-affected orange fruit. Juice extracted via SFE resulted in a lower yield with lower peel oil and higher pellet (peel tissue particles) content compared to juice obtained via RE. The SFE juice also had higher levels of hesperidin and other flavonoid glycosides, mainly due to plentiful peel tissue particles. The SFE juice was also abundant in carotenoids due to a large amount of flavedo particles in the juice. On the other hand, polymethoxylated flavones occurred at higher concentrations in the RE juice, and this may be due to the higher peel oil content in this juice. The SFE juice was rich in flavonoid glycosides and carotenoids, which are associated with potential antioxidant properties; however, the extra portion of the phytonutrients mostly existed in the pellets and possibly had low bioavailability. The results obtained from the HLB-affected oranges are in agreement with the previous observations of healthy oranges.

Physiological effects of tangeretin and heptamethoxyflavone on obese C57BL/6J mice fed a high-fat diet and analyses of the metabolites originating from these two polymethoxylated flavones

Two compounds from citrus peel, tangeretin (TAN) and 3',4',3,5,6,7,8-heptamethoxyflavone (HMF), were investigated for their abilities to repair metabolic damages caused by an high-fat diet (HFD) in C57BL/6J mice. In the first 4 weeks, mice were fed either a standard diet (11% kcal from fat) for the control group, or a HFD (45% kcal from fat) to establish obesity in three experimental groups. In the following 4 weeks, two groups receiving the HFD were supplemented with either TAN or HMF at daily doses of 100 mg/kg body weight, while the two remaining groups continued to receive the standard healthy diet or the nonsupplemented HFD. Four weeks of supplementation with TAN and HMF resulted in intermediate levels of blood serum glucose, leptin, resistin, and insulin resistance compared with the healthy control and the nonsupplemented HFD groups. Blood serum peroxidation (TBARS) levels were significantly lower in the TAN and HMF groups compared with the nonsupplemented HFD group. Several differences occurred in the physiological effects of HMF versus TAN. TAN, but not HMF, reduced adipocyte size in the mice with pre-existent obesity, while HMF, but not TAN, decreased fat accumulation in the liver and also significantly increased the levels of an anti-inflammatory cytokine, IL-10. In an analysis of the metabolites of TAN and HMF, several main classes occurred, including a new set of methylglucuronide conjugates. It is suggested that contrasts between the observed physiological effects of TAN and HMF may be attributable to the differences in numbers and chemical structures of TAN and HMF metabolites.

Therapeutic Implications of a Polymethoxylated Flavone, Tangeretin, in the Management of Cancer via Modulation of Different Molecular Pathways

Chemotherapeutics can induce oxidative stress, inflammation, apoptosis, mitochondrial dysfunction, and abnormalities in neurotransmitter metabolism leading to toxicity. Because there have been no therapeutic strategies developed to target inflammation and oxidative stress, there is a continuing need for new and improved therapy. As a result, there has been increasing interest in complementary and alternative medicine with anticancer potential. Studies have shown that the antioxidant activities and anti-inflammatory effects of citrus fruits are promising natural phytochemicals in the development of new anticancer agents. Tangeretin is a naturally polymethoxylated flavone compound extracted from the citrus peel that has shown significant intestinal absorption and adequate bioavailability, with the added benefit of promoting longevity. In addition, tangeretin is known to exhibit considerable selective toxicity to many types of cancer cell proliferation such as ovarian, brain, blood, and skin cancer. Evidence indicates that tangeretin acts through several mechanisms including growth inhibition, induction of apoptosis, autophagy, antiangiogenesis, and estrogenic-like effects. Furthermore, tangeretin works through mitigating levels of inflammatory mediators in the immune system. Using tangeretin in combination with clinically applied anticancer drugs could be a good strategy for increasing the efficiency of these agents and protecting noncancerous cells from damage caused by chemotherapy. The purpose of this review is to highlight the protective effects of a novel natural product, tangeretin against chemotherapeutic-induced toxicity. The development of chemoprevention strategies can lead to significant health care improvement in cancer survivors. Thus, study outcomes may attract more investigators to conduct tangeretin-related research and find out potentially significant impacts on health care of cancer patients and decreased health problems associated with chemotherapeutics-induced toxicity.

Impact of orange juice consumption on cardiovascular disease risk factors: a systematic review and meta-analysis of randomized-controlled trials

Cardiovascular disease (CVD) is the greatest cause of premature death and disability globally. Numerous therapeutic strategies have been developed to improve and prevent the adverse cardiovascular events, including nutritional approaches. This systematic review and meta-analysis summarized the evidence on orange juice consumption on CVD risk factors. Four databases were searched up to September 2020. Ten randomized controlled trials were included in the final analysis. Pooled results demonstrated a significant effect of orange juice on glucose (WMD: -2.92 mg/dl, 95% CI: -5.327, -0.530, p = 0.017), insulin (WMD: -1.229 μU/ml, 95% CI: -2.083, -0.374, p = 0.005), HOMA-IR (WMD: -0.464, 95% CI: -0.747, -0.181, p = 0.001), total cholesterol (WMD: -9.84 mg/dl, 95% CI: -15.43, -4.24, p = 0.001), LDL-C (WMD: -9.14 mg/dl, 95% CI: -15.79, -2.49, p = 0.007), and CRP (WMD: -0.467 mg/l, 95% CI: -0.815, -0.120, p = 0.008) compared to control group. However, the effect of orange juice on body composition factors and other CVD risk factors was not significant compared to control group. These lowering effects of glucose, HOMA-IR, total cholesterol, and LDL-C were robust in subgroups with orange juice consumption ≥500 ml/day. This meta-analysis suggests that orange juice may be beneficial in improving several CVD risk factors.

Flavonoids in adipose tissue inflammation and atherosclerosis: one arrow, two targets

Flavonoids are polyphenolic compounds naturally occurring in fruits and vegetables, in addition to beverages such as tea and coffee. Flavonoids are emerging as potent therapeutic agents for cardiovascular as well as metabolic diseases. Several studies corroborated an inverse relationship between flavonoid consumption and cardiovascular disease (CVD) or adipose tissue inflammation (ATI). Flavonoids exert their anti-atherogenic effects by increasing nitric oxide (NO), reducing reactive oxygen species (ROS), and decreasing pro-inflammatory cytokines. In addition, flavonoids alleviate ATI by decreasing triglyceride and cholesterol levels, as well as by attenuating inflammatory mediators. Furthermore, flavonoids inhibit synthesis of fatty acids and promote their oxidation. In this review, we discuss the effect of the main classes of flavonoids, namely flavones, flavonols, flavanols, flavanones, anthocyanins, and isoflavones, on atherosclerosis and ATI. In addition, we dissect the underlying molecular and cellular mechanisms of action for these flavonoids. We conclude by supporting the potential benefit for flavonoids in the management or treatment of CVD; yet, we call for more robust clinical studies for safety and pharmacokinetic values.

Microencapsulation of Tangeretin in a Citrus Pectin Mixture Matrix

The objectives of this research were to microencapsulate tangeretin, and to evaluate the basic characteristics of the microcapsule products. Tangeretin is a polymethoxyflavone (PMF) which has been revealed to possess various health benefits and is abundant in tangerine and other citrus peels. Microencapsulation technology is widely employed in the food and pharmaceutical industries to exploit functional ingredients, cells, and enzymes. Spray drying is a frequently applied microencapsulation method because of its low cost and technical requirements. In this research, tangeretin dissolved at different concentrations in bergamot oil was microencapsulated in a citrus pectin/sodium alginate matrix. The resulting microcapsule powder showed promising physical and structural properties. The retention efficiency of tangeretin was greater at a concentration of 2.0% (98.92%) than at 0.2% (71.05%), probably due to the higher temperature of the emulsion during the homogenizing and spray-drying processes. Encapsulation efficiency was reduced with increased concentration of tangeretin. Our results indicate that tangeretin could be successfully encapsulated within a citrus pectin/sodium alginate matrix using bergamot oil as a carrier.

Inhibitory effects of tangeretin and trans-ethyl caffeate on the HMG-CoA reductase activity: Potential agents for reducing cholesterol levels

One of the pathways to reduce cholesterol production in the liver is through the inhibition of HMG-Coa reductase (HMGCR) by current drugs, statins. However, these have side effects if consumed in prolonged periods. Tangeretin and trans-ethyl caffeate as alternative drugs in reducing hypercholesterolemia and preventing atherosclerosis have never been reported. Their effects on inhibiting HMGCR activity were investigated through enzymatic method (in vitro and in vivo). The toxicity property was analyzed on the Serum Glutamate Oxalate Transaminase (SGOT)/Serum Glutamate Piruvate Transaminase (SGPT) levels and rat liver histology. The results showed that both compounds inhibited HMGCR activity significantly compare to the control simvastatin (p < 0.05). Tangeretin which showed very good activity in inhibiting HMGCR (83.8 of % inhibition, equal to simvastatin) was selected and used for anti-hypercholesterolemia in vivo assessment. Furthermore, tangeretin was shown to effectively reduced Total Cholesterol (TC) and Low Density Lipoprotein (LDL), and increased High Density Lipoprotein (HDL) levels significantly compared to the simvastatin group (p < 0.05). Tangeretin group was also proven to inhibit HMGCR rat liver activity significantly compare to the control simvastatin (p < 0.05). The toxicity study on the SGOT/SGPT levels and liver histology revealed that there were no side effects after administration by tangeretin. Results found that both tangeretin and trans-ethyl caffeate are potent candidates as anti-hypercholesterolemia agent in vitro. In addition, tangeretin was also shown to be safe and suitable as an alternative treatment for controlling hypercholesterolemia in vivo as well as have potency for preventing atherosclerosis.

Exploiting Citrus aurantium seeds and their secondary metabolites in the management of Alzheimer disease

Fruit by-products are considered nature’s golden gift for human health and a good starting point to discover new drugs depending on the fact that they contain millions of bio-active compounds that are responsible for therapeutic activities. In this context, the main goal of this study is to recycle Citrus aurantium (C. aurantium) seeds to produce pharmaceutical molecules to be used in the prevention of the progressive neurological damage associated with Alzheimer disease (AD). Donepezil (0.75 mg/kg), hesperidin (125 and 250 mg/kg) and limonoids (50 and 100 mg/kg) were used for treatment of rats for 2 weeks prior to concomitant administration of AlCl₃ for three successive weeks. Protection against cognitive deterioration was observed among study group with insignificant difference from normal control group and significant difference from positive control group in the Y-Maze test. On the other hand, treatment with both doses of hesperidin (125 and 250 mg/kg) and high dose of limonoids only (100 mg/kg) produced improvement in psychological state, observed by significant increase in ambulation frequency in comparison to positive control group, however it was not as frequent as normal group, as it was significantly less than normal group in the open field test. Regarding acetylcholine esterase (AChE) and beta-amyloid (β amyloid) levels, the effect of limonoids low dose was the best as it didn’t have a significant effect when compared to normal control, also hesperidin in both doses showed insignificant effects on β amyloid levels when compared to normal control group. Our results encourage the use of C. aurantium seeds which are wasted in huge amounts, as Alzheimer prophylactic food additives.

Hepatic Lipidomics Analysis Reveals the Antiobesity and Cholesterol-Lowering Effects of Tangeretin in High-Fat Diet-Fed Rats

Tangeretin (TAN) exhibited antilipogenic, antidiabetic, and lipid-lowering effects. However, the lipid biomarkers and the underlying mechanisms for antiobesity and cholesterol-lowering effects of TAN have not been sufficiently investigated. Herein, we integrated biochemical analysis with lipidomics to elucidate its efficacy and mechanisms in high-fat diet-fed rats. TAN at supplementation levels of 0.04 and 0.08% not only significantly decreased body weight gain, serum total cholesterol, and low-density lipoprotein cholesterol levels but also ameliorated hepatic steatosis. These beneficial effects were associated with the declining levels of fatty acids, diacylglycerols (DGs), triacylglycerols, ceramides, and cholesteryl esters by hepatic lipidomics analysis, which were attributed to downregulating lipogenesis-related genes and upregulating lipid oxidation- and bile acid biosynthesis-related genes. Additionally, 21 lipids were identified as potential lipid biomarkers, such as DGs and phosphatidylethanolamines. These findings indicated that the modulation of lipid homeostasis might be the key pathways for the mechanisms of TAN in the antiobesity and cholesterol-lowering effects.

Citrus Peel Flavonoids as Potential Cancer Prevention Agents

Citrus fruit and in particular flavonoid compounds from citrus peel have been identified as agents with utility in the treatment of cancer. This review provides a background and overview regarding the compounds found within citrus peel with putative anticancer potential as well as the associated in vitro and in vivo studies. Historical studies have identified a number of cellular processes that can be modulated by citrus peel flavonoids including cell proliferation, cell cycle regulation, apoptosis, metastasis, and angiogenesis. More recently, molecular studies have started to elucidate the underlying cell signaling pathways that are responsible for the flavonoids' mechanism of action. These growing data support further research into the chemopreventative potential of citrus peel extracts, and purified flavonoids in particular. This critical review highlights new research in the field and synthesizes the pathways modulated by flavonoids and other polyphenolic compounds into a generalized schema.

Determination of isosinensetin in rat plasma by UHPLC-MS/MS: Application to oral and intravenous pharmacokinetic study in healthy rats

Isosinensetin is a polymethoxyflavone existing in various kinds of citrus. It has exhibited significant anti-proliferative activity and herb-drug interaction. To date, a specific determination method to quantify isosinensetin concentration in biological matrix has not been developed. In the present study, a highly specific, simple and sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) approach was developed and validated for quantification of isosinensetin in rat plasma with subsequent application to a pharmacokinetic study. Isosinensetin and lysionotin (internal standard, IS) were extracted from rat plasma by a single step protein precipitation using acetonitrile as precipitation agent. The chromatographic separation was conducted using an Agilent C18 column with a gradient elution system (0.1 % formic acid aqueous solution and acetonitrile) within 3.5 min. An electrospray ionization (ESI) source operating in positive mode and multiple reaction monitoring (MRM) were used to monitor the transitions of m/z 373.1 → 343.1 for isosinensetin and m/z 345.1 → 315.1 for IS. The developed method was linear within the range of 1-1000 ng/mL and fully validated according to FDA guidelines. The accuracy values reported as relative errors were between 2.0 and 10.0 % for three quality control levels (2, 400 and 800 ng/mL) and lower limit of quantification (LLOQ). The precisions were ≤11.1 % for quality controls and ≤18.1 % for LLOQ. The recoveries and matrix effects of isosinensetin were in the range of 83.4-87.7 % and 105.6-108.8 %, respectively. Other parameters such as selectivity, carryover effect, dilution integrity and stability were also validated and met the acceptance criteria. The method was applied to a pharmacokinetic study in rats following oral and intravenous administration of isosinensetin. Isosinensetin was rapidly absorbed with a poor bioavailability of 2.19 % and quickly eliminated with mean half-life of 1.40 h and 1.76 h for oral and intravenous route, respectively.

Phenolic composition, antioxidant potential and health benefits of citrus peel

Citrus peel (CP) forms around 40-50% of the total fruit mass but is generally thought to be a waste. However, it is a substantial source of naturally occurring health enhancing compounds, particularly phenolic compounds and carotenoids. Phenolic compounds in CP mainly comprise phenolic acids (primarily caffeic, p-coumaric, ferulic and sinapic acid), flavanones (generally naringin and hesperidin) and polymethoxylated flavones (notably nobiletin and tangeretin). It has also been noted that CP's contain more amounts of these compounds than corresponding edible parts of the fruits. Phenolic compounds present in CP act as antioxidants (by either donation of protons or electrons) and protect cells against free radical damage as well as help in reducing the risk of many chronic diseases. Owing to the more abundance of polyphenols in CP's, their antioxidant activity is also higher than other edible fruit parts. Therefore, peels from citrus fruits can be used as sources of functional compounds and preservatives for the development of newer food products, that are not only safe but also have health-promoting activities. The present review provides in-depth knowledge about the phenolic composition, antioxidant potential and health benefits of CP.