The effects of citrus flavonoids supplementation on endothelial function: A systematic review and dose-response meta-analysis of randomized clinical trials.

The present systematic review and dose-response meta-analysis was conducted to synthesize existing data from randomized clinical trials (RCTs) concerning the impact of citrus flavonoids supplementation (CFS) on endothelial function. Relevant RCTs were identified through comprehensive searches of the PubMed, ISI Web of Science, and Scopus databases up to May 30, 2023. Weighted mean differences and their corresponding 95% confidence intervals (CI) were pooled utilizing a random-effects model. A total of eight eligible RCTs, comprising 596 participants, were included in the analysis. The pooled data demonstrated a statistically significant augmentation in flow-mediated vasodilation (FMD) (2.75%; 95% CI: 1.29, 4.20; I2 = 87.3%; p < 0.001) associated with CFS compared to the placebo group. Furthermore, the linear dose-response analysis indicated that each increment of 200 mg/d in CFS led to an increase of 1.09% in FMD (95% CI: 0.70, 1.48; I2 = 94.5%; p < 0.001). The findings from the nonlinear dose-response analysis also revealed a linear relationship between CFS and FMD (Pnon-linearity = 0.903, Pdose-response <0.001). Our findings suggest that CFS enhances endothelial function. However, more extensive RTCs encompassing longer intervention durations and different populations are warranted to establish more precise conclusions.

Assessment of the in vitro acaricidal activity of Bravecto® (fluralaner) and a proposed orange oil-based formulation vehicle for the treatment of Sarcoptes scabiei.

BACKGROUND: Sarcoptic mange is a serious animal welfare concern in bare-nosed wombats (Vombatus ursinus). Fluralaner (Bravecto®) is a novel acaricide that has recently been utilised for treating mange in wombats. The topical 'spot-on' formulation of fluralaner can limit treatment delivery options in situ, but dilution to a volume for 'pour-on' delivery is one practicable solution. This study investigated the in vitro acaricidal activity of Bravecto, a proposed essential oil-based diluent (Orange Power®), and two of its active constituents, limonene and citral, against Sarcoptes scabiei. METHODS: Sarcoptes scabiei were sourced from experimentally infested pigs. In vitro assays were performed to determine the lethal concentration (LC50) and survival time of the mites when exposed to varying concentrations of the test solutions. RESULTS: All compounds were highly effective at killing mites in vitro. The LC50 values of Bravecto, Orange Power, limonene and citral at 1 h were 14.61 mg/ml, 4.50%, 26.53% and 0.76%, respectively. The median survival times of mites exposed to undiluted Bravecto, Orange Power and their combination were 15, 5 and 10 min, respectively. A pilot survival assay of mites collected from a mange-affected wombat showed survival times of < 10 min when exposed to Bravecto and Orange Power and 20 min when exposed to moxidectin. CONCLUSIONS: These results confirm the acaricidal properties of Bravecto, demonstrate acaricidal properties of Orange Power and support the potential suitability of Orange Power and its active constituents as a diluent for Bravecto. As well as killing mites via direct exposure, Orange Power could potentially enhance the topical delivery of Bravecto to wombats by increasing drug penetration in hyperkeratotic crusts. Further research evaluating the physiochemical properties and modes of action of Orange Power and its constituents as a formulation vehicle would be of value.

Influence of Citrus sunki and Poncirus trifoliata Root Extracts on Metabolome of Phytophthora parasitica.

Phytophthora parasitica is an oomycete pathogen that infects a broad range of crops of worldwide economic interest; among them are citrus species. In general, some Citrus and the rootstocks of related genera offer considerable resistance against P. parasitica; therefore, understanding the mechanisms involved in the virulence of this pathogen is crucial. In this work, P. parasitica secondary metabolite production was studied using matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI-MSI) and ultrahigh-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry (UHPLC/ESI-Q-TOF-MS) combined with chemometric tools, and its metabolic profile was evaluated under the influence of Citrus sunki (a highly susceptible host) and Poncirus trifoliata (a resistant genotype) extracts. The root extracts of Citrus sunki had an influence on the growth and hyphae morphology, and the root extracts of P. trifoliata had an influence on the zoospore behavior. In parallel, the spatial distribution of several metabolites was revealed in P. parasitica colonies using MALDI-MSI, and the metabolite ion of m/z 246 was identified as the protonated molecule of Arg-Ala. The MALDI-MSI showed variations in the surface metabolite profile of P. parasitica under the influence of the P. trifoliata extract. The P. parasitica metabolome analysis using UHPLC-ESI-Q-TOF-MS resulted in the detection of Arg-Gln (m/z 303.1775), as well as L-arginine (m/z 175.1191) and other unidentified metabolites. Significant variations in this metabolome were detected under the influence of the plant extracts when evaluated using UHPLC-ESI-Q-TOF-MS. Both techniques proved to be complementary, offering valuable insights at the molecular level when used to assess the impact of the plant extracts on microbial physiology in vitro. The metabolites identified in this study may play significant roles in the interaction or virulence of P. parasitica, but their functional characterization remains to be analyzed. Overall, these data confirm our initial hypotheses, demonstrating that P. parasitica has the capabilities of (i) recognizing host signals and altering its reproductive programing and (ii) distinguishing between hosts with varying responses in terms of reproduction and the production of secondary metabolites.

Effect of Chitosan-Riboflavin Bioconjugate on Green Mold Caused by Penicillium digitatum in Lemon Fruit.

Penicillium digitatum is the causal agent of green mold, a primary postharvest disease of citrus fruits. This study evaluated the efficacy of a novel photoactive chitosan-riboflavin bioconjugate (CH-RF) to control green mold in vitro and in lemon fruit. The results showed total inhibition of P. digitatum growth on APDA supplemented with CH-RF at 0.5% (w/v) and a significant reduction of 84.8% at 0.25% (w/v). Lemons treated with CH-RF and kept under controlled conditions (20 °C and 90-95% relative humidity) exhibited a noteworthy reduction in green mold incidence four days post-inoculation. Notably, these effects persisted, with all treatments remaining significantly distinct from the control group until day 14. Furthermore, CH-RF showed high control of green mold in lemons after 20 days of cold storage (5 ± 1 °C). The disease incidence five days after cold storage indicated significant differences from the values observed in the control. Most CH-RF treatments showed enhanced control of green mold when riboflavin was activated by white-light exposure. These findings suggest that this novel fungicide could be a viable alternative to conventional synthetic fungicides, allowing more sustainable management of lemon fruit diseases.

[Intensive Citrus Cultivation Suppresses Soil Phosphorus Cycling Microbial Activity].

Soil microbes are key drivers in regulating the phosphorus cycle. Elucidating the microbial mineralization process of soil phosphorus-solubilizing bacteria is of great significance for improving nutrient uptake and yield of crops. This study investigated the mechanism by which citrus cultivation affects the soil microbial acquisition strategy for phosphorus by measuring the abundance of the phoD gene, microbial community diversity and structure, and soil phosphorus fractions in the soils of citrus orchards and adjacent natural forests. The results showed that citrus cultivation could lead to a decrease in soil pH and an accumulation of available phosphorus in the soil, with a content as high as 112 mg·kg-1, which was significantly higher than that of natural forests (3.7 mg·kg-1). Citrus cultivation also affected the soil phosphorus fractions, with citrus soil having higher levels of soluble phosphorus (CaCl2-P), citrate-extractable phosphorus (Citrate-P), and mineral-bound phosphorus (HCl-P). The phosphorus fractions of natural forest soils were significantly lower than those of citrus soils, whereas the phoD gene abundance and alkaline phosphatase activity were significantly higher in natural forest soils than in citrus soils. High-throughput sequencing results showed that the Shannon diversity index of phosphate-solubilizing bacteria in citrus soils was 4.61, which was significantly lower than that of natural forests (5.35). The microbial community structure in natural forests was also different from that of citrus soils. In addition, the microbial community composition of phosphate-solubilizing bacteria in citrus soils was also different from that of natural forests, with the relative abundance of Proteobacteria being lower in natural forest soils than in citrus soils. Therefore, citrus cultivation led to a shift of soil microbial acquisition strategy for phosphorus, with external phosphorus addition being the main strategy in citrus soils, whereas microbial mineralization of organic phosphorus was the main strategy in natural forest soils to meet their growth requirements.

Recent advances in the therapeutic potential of nobiletin against respiratory diseases.

BACKGROUND: Nobiletin is a natural polymethoxylated flavonoid widely present in citrus fruit peels. It has been demonstrated to exert the effects of anti-tumor, anti-inflammation, anti-oxidative, anti-apoptotic and improve cardiovascular function. Increasing evidences suggest that nobiletin plays an important role in respiratory diseases (RDs) treatment. OBJECTIVE: This review aimed to investigate the therapeutic potential of nobiletin against RDs, such as lung cancer, COPD, pulmonary fibrosis, asthma, pulmonary infection, acute lung injury, coronavirus disease 2019, and pulmonary arterial hypertension. METHODS: We retrieved extensive literature of relevant literatures in English until June 26, 2023 from the database of PubMed, Web of Science, and Scopus databases. The keywords of "nobiletin and lung", "nobiletin and respiratory disease", "nobiletin and chronic respiratory diseases", "nobiletin and metabolites", "nobiletin and pharmacokinetics", "nobiletin and toxicity" were searched in pairs. A total of 298 literatures were retrieved from the above database. After excluding the duplicates and reviews, 53 were included in the current review. RESULTS: We found that the therapeutic mechanisms are based on different signaling pathways. Firstly, nobiletin inhibited the proliferation and suppressed the invasion and migration of cancer cells by regulating the related pathway or key target, like Bcl-2, PD-L1, PARP, and Akt/GSK3ß/ß-catenin in lung cancer treatment. Secondly, nobiletin treats COPD and ALI by targeting classical signaling pathway mediating inflammation. Besides, the available findings show that nobiletin exerts the effect of PF treatment via regulating mTOR pathway. CONCLUSIONS: With the wide range of pharmacological activities, high efficiency and low toxicity, nobiletin can be used as a potential agent for preventing and treating RDs. These findings will contribute to further research on the molecular mechanisms of nobiletin and facilitate in-depth studies on nobiletin at both preclinical and clinical levels for the treatment of RDs.

Enhancement of hepatoprotective activity of limonin from citrus seeds against acetaminophen-induced liver injury by HSCCC purification and liposomal encapsulation.

Limonin is a natural tetracyclic triterpenoid compound in citrus seeds that presents hepatoprotective effects but is often discarded as agricultural waste because of its low content and low solubility. Herein, limonin with high purity (98.11%) from citrus seeds was obtained via purification by high-speed counter-current chromatography (HSCCC) and recrystallization. Limonin-loaded liposomes (Lip-LM) prepared by thin film hydration and high pressure homogenization method to enhance its solubility and hepatoprotective effect on APAP-induced liver injury (AILI). Lip-LM appeared as lipid nanoparticles under a transmission electron microscope, and showed well dispersed nano-scale size (69.04 ± 0.42 nm), high encapsulation efficiency (93.67% ± 2.51%), sustained release, fine stability. Lip-LM also exhibited significantly better hepatoprotective activity on AILI than free limonin in vivo. In summary, Lip-LM might be used as a potential hepatoprotective agent in the form of dietary supplement and provide an effective strategy to improve the potential value of citrus seeds.

Nigella sativa, Anthemis hyaline and Citrus sinensis extracts reduce SARS-CoV-2 replication by fluctuating Rho GTPase, PI3K-AKT, and MAPK/ERK pathways in HeLa-CEACAM1a cells.

Traditional remedies have long utilized Anthemis hyaline, Nigella sativa, and Citrus sinensis peel extracts as treatments for microbial infections. This study aimed to investigate the influence of Anthemis hyaline, Nigella sativa, and Citrus sinensis extracts on coronavirus replication and apoptosis-related pathways. HeLa-CEACAM1a cells were exposed to mouse hepatitis virus-A59. After viral inoculation, the mRNA levels of 36 genes were quantified using a Fluidigm Dynamic Array nanofluidic chip. IL-8 level and intracellular Ca2+ concentration was measured, and viral titer was assessed by the TCID50/ml assay to detect the extent of infection. Treatment with Nigella sativa extract surged the inflammatory cytokine IL-8 level at both 24 and 48-hour. Changes in gene expression were notable for RHOA, VAV3, ROCK2, CFL1, RASA1, and MPRIP genes following treatment with any of the extracts. The addition of Anthemis hyaline, Nigella sativa, or Citrus sinensis extracts to coronavirus-infected cells reduced viral presence, with Anthemis hyaline extract leading to a virtually undetectable viral load at 6- and 8-hours after infection. While all treatments influenced IL-8 production and viral levels, Anthemis hyaline extract displayed the most pronounced reduction in viral load. Consequently, Anthemis hyaline extract emerges as the most promising agent, harboring potential therapeutic compounds.

Metabolomic analysis reveals the effect of ultrasonic-microwave pretreatment on flavonoids in tribute Citrus powder.

In this study, the ultrasonic-microwave pretreatment was defined as a processing technology in the production of tribute citrus powder, and it could increase the flavonoid compounds in the processing fruit powder. A total of 183 upregulated metabolites and 280 downregulated metabolites were obtained by non-targeted metabolomics, and the differential metabolites was mainly involved in the pathways of flavonoid biosynthesis, flavone and flavonol biosynthesis. A total of 8 flavonoid differential metabolites were obtained including 5 upregulated metabolites (6"-O-acetylglycitin, scutellarin, isosakuranin, rutin, and robinin), and 3 downregulated metabolites (astragalin, luteolin, and (-)-catechin gallate) by flavonoids-targeted metabolomics. The 8 flavonoid differential metabolites participated in the flavonoid biosynthesis pathways, flavone and flavonol biosynthesis pathways, and isoflavonoid biosynthesis pathways. The results provide a reference for further understanding the relationship between food processing and food components, and also lay a basis for the development of food targeted-processing technologies.

Anti-Obesity Effect of Jeju Roasted Citrus Peel Extract in High-Fat Diet-Induced Obese Mice and 3T3-L1 Adipocytes Via Lipid Metabolism Regulation.

Lipid accumulation in adipocytes occurs through multifactorial effects such as overnutrition due to unbalanced eating habits, reduced physical activity, and genetic factors. In addition, obesity can be intensified by the dis-regulation of various metabolic systems such as differentiation, lipogenesis, lipolysis, and energy metabolism of adipocytes. In this study, the Jeju roasted peel extract from Citrus unshiu S.Markov. (JRC), which is discarded as opposed to the pulp of C. unshiu S.Markov., is commonly consumed to ameliorate obesity. To investigate the anti-obesity effect of JRC, these studies were conducted on differentiated 3T3-L1 cells and in high-fat diet-induced mice, and related methods were used to confirm whether it decreased lipid accumulation in adipocytes. The mechanism of inhibiting obesity by JRC was confirmed through mRNA expression studies. JRC suppressed lipid accumulation in adipocytes and adipose tissue, and significantly improved enzymes such as alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transferase and serum lipid profiles. In addition, it effectively modulated the expression of genes related to lipid and energy metabolism in adipose tissue. As a result, these findings suggest that JRC could be a therapeutic regulator of body fat accumulation by significantly alleviating the dis-regulation of intracellular lipid metabolism in adipocytes and by enhancement of energy metabolism (Approval No. CNU IACUC-YB-2023-98).

Supplementation of citrus pectin with whole-cell pectinase PG5 on Pichia pastoris promotes recovery of colitis and enhances intestinal barrier function in DSS-treated mice.

A whole-cell biocatalyst was developed by genetically engineering pectinase PG5 onto the cell surface of Pichia pastoris using Gcw12 as the anchoring protein. Whole-cell PG5 eliminated the need for enzyme extraction and purification, while also exhibiting enhanced thermal stability, pH stability, and resistance to proteases in vitro compared to free PG5. Magnetic resonance mass spectrometry analysis revealed that whole-cell PG5 efficiently degraded citrus pectin, resulting in the production of a mixture of pectin oligosaccharides. The primary components of the mixture were trigalacturonic acid, followed by digalacturonic acid and tetragalacturonic acid. Supplementation of citrus pectin with whole-cell PG5 resulted in a more pronounced protective effect compared to free PG5 in alleviating colitis symptoms and promoting the integrity of the colonic epithelial barrier in a mouse model of dextran sulfate sodium-induced colitis. Hence, this study demonstrates the potential of utilizing whole-cell pectinase as an effective biocatalyst to promote intestinal homeostasis in vivo.

Analytical rheology as a tool for the structural investigation of citrus pectin.

Rheological analysis of citrus pectin at pH 3 and 7 elucidates its structural dynamics, revealing distinct behaviors influenced by pH. At pH 3, pectin exhibits shear-thinning, with solvent-independent unified rheological profiles identifying three concentration regimes: 0.5%-1.5%, 2%-3%, and 3.5%-4%. These regimes, alongside Cox-Merz superpositions, outline the semi-dilute (c*) and concentrated (c**) transitions at 1.5%-2% and 3%-3.5%, respectively. Moreover, a Morris equation exponent of 0.65 indicates flexible, mobility-restricted macromolecules. Conversely, at pH 7, increased viscosities and Morris plot linearity for p = .1 suggest rigid chain behavior due to electrostatic repulsion among ionized acidic groups. This rigidity leads to concentration-dependent self-assembly structures that diverge from expected unified rheological profiles, a deviation amplified by heating-cooling cycles. This study clarifies the impact of pH on citrus pectin's rheology and emphasizes the intricate relationship between polymeric chain rigidity, self-assembly, and viscosity. By providing a refined understanding of these mechanisms, our findings contribute to the broader field of polysaccharide research, offering insights critical for developing and optimizing pectin-based applications in various industries.

Preparation of limonin monoclonal antibody and establishment of a sensitive icELISA for analyzing limonin in citrus and herbal samples.

Limonin is an intensely bitter and highly oxidized tetracyclic triterpenoid secondary metabolite, which is abundant in the Rutaceae and Meliaceae, especially in Citrus. In order to detect limonin content in complex substrates such as citrus and traditional Chinese medicine, monoclonal antibodies specifically recognizing limonin were prepared and an indirect competitive enzyme-linked immunosorbent assay (icELISA) was established. The median inhibition concentration (IC50) was 5.40 ng/mL and the linear range was 1.25-23.84 ng/mL. The average recoveries from citrus peel and pulp samples were 95.9%-118.8% and 77.5%-113.1%, respectively. Moreover, the contents of limonin in 6 citrus samples and 4 herbal samples were analyzed by icELISA and UPLC-MS, and the results of the two methods were consistent. This validation is sufficient to demonstrate that the developed immunoassay is applicable for the detection of limonin in citrus and herbal samples and has the advantage of high efficiency, sensitivity, and convenience.

Citrus pectin protects mice from burn injury by modulating intestinal microbiota, GLP-1 secretion and immune response.

Water-soluble rhamnogalacturonan-I enriched citrus pectin (WRP) has promising effect on antimicrobial defense. We aim to determine whether the modified acidic (A) or neutral (B) WRP solutions can improve intestinal microbial dysbiosis in burn-injured mice. Male Balb/c mice were gavaged with WRPs at 80, 160, 320 mg/kg. Body weight daily for 21 days before exposed to thermal injury of 15 % total body surface area and mortality was monitored. Mice with 80 mg/kg WRPs were also subjected to fecal DNAs and T cell metabonomics analysis, intestinal and plasma glucagon-like peptide 1 (GLP-1) detection, plasma defensin, immunoglobin and intestinal barrier examinations at 1 and 3d postburn (p.b.). Burn-induced mortality was only improved by low dose WRP-A (P = 0.039). Both WRPs could prevent the dysbiosis of gut microbiota in burn injury by reducing the expansion of inflammation-promoting bacteria. Both WRPs suppressed ileum GLP-1 production at 1d p.b. (P = 0.002) and plasma GLP-1 levels at 3d p.b. (P = 0.013). Plasma GLP-1 level correlated closely with ileum GLP-1 production (P = 0.019) but negatively with microbiota diversity at 1d p.b. (P = 0.003). Intestinal T cell number was increased by both WRPs in jejunum at 3d p.b. However, the exaggerated splenic T cell metabolism in burn injury was reversed by both WRPs at 1d p.b. The burn-increased plasma defensin ß1 level was only reduced by WRP-B. Similarly, the intestinal barrier permeability was only rescued by WRP-B at 1d p.b. WRP-A rather than WRP-B could reduce burn-induced mortality in mice by suppressing intestinal GLP-1 secretion, restoring gut microbiota dysbiosis and improving adaptive immune response.

Transcriptomic and targeted metabolome analyses revealed the regulatory mechanisms of the synthesis of bioactive compounds in Citrus grandis 'tomentosa'.

Exocarpium Citri Grandis is a popular Chinese herbal medicine prepared from Citrus grandis 'tomentosa', and it is rich in several bioactive compounds, including flavonoids, coumarins, and volatile oils. However, studies are yet to elucidate the mechanisms of synthesis and regulation of these active components. Therefore, the present study examined the profiles of flavonoids and volatile oil bioactive compounds in plant petals, fruits, and tender leaves, and then performed RNA sequencing on different tissues to identify putative genes involved in the synthesis of bioactive compounds. The results show that the naringin, naringenin, and coumarin contents of the fruitlets were significantly higher than those of the tender leaves and petals, whereas the tender leaves had significantly higher levels of rhoifolin and apigenin. A total of 49 volatile oils, of which 10 were mainly found in flowers, 15 were mainly found in fruits, and 18 were mainly found in leaves, were identified. RNA sequencing identified 9,942 genes that were differentially expressed in different tissues. Further analysis showed that 20, 15, and 74 differentially expressed genes were involved in regulating flavonoid synthesis, regulating coumarin synthesis, and synthesis and regulation of terpenoids, respectively. CHI1 (Cg7g005600) and 1,2Rhat gene (Cg1g023820) may be involved in the regulation of naringin synthesis in C. grandis fruits. The HDR (Cg8g006150) gene, HMGS gene (Cg5g009630) and GGPS (Cg1g003650) may be involved in the regulation and synthesis of volatile oils in C. grandis petals. Overall, the findings of the present study enhance our understanding of the regulatory mechanisms of secondary metabolites in C. grandis, which could promote the breeding of C. grandis with desired characteristics.

Efficacy of Crataegus Extract Mixture on Body Fat and Lipid Profiles in Overweight Adults: A 12-Week, Randomized, Double-Blind, Placebo-Controlled Trial.

A Crataegus Extract Mixture (CEM) is a combination of extracts from Crataegus pinnatifida leaves and Citrus unshiu peels, well-known herbs used for treating obesity and dyslipidemia. We aimed to investigate the efficacy and safety of a CEM on the body fat and lipid profiles in overweight adults. A 12-week, randomized, double-blind, placebo-controlled, parallel-group trial was conducted on 105 subjects aged 20-60 years with body mass indexes between 25 and 30 kg/m2. Eligible subjects were randomly assigned in a 1:1:1 ratio to receive either a high dose of the CEM (400 mg tid), a low dose of the CEM (280 mg tid), or a placebo. Body fat was evaluated using dual-energy X-ray absorptiometry (DXA), bioelectrical impedance analysis (BIA), and anthropometric measurements. The blood lipid and adipokine profiles were measured before and after the administration. After 12 weeks, the reductions in the fat percentages measured by DXA and BIA were significantly greater in the CEM groups than in the placebo group. The CEM also significantly decreased the body weights, body mass indexes, and blood leptin levels. An additional per-protocol analysis revealed that the high dose of the CEM also lowered the blood levels of triglycerides and very low-density lipoprotein cholesterol. No adverse events occurred after the CEM treatment. Our results suggest that CEMs are safe and effective for reducing the body fat and body weight and regulating the blood lipid and leptin levels in overweight or mildly obese individuals.

Variation of the essential oil components of Citrus aurantium leaves upon using different distillation techniques and evaluation of their antioxidant, antidiabetic, and neuroprotective effect against Alzheimer's disease.

Citrus fruit essential oil is considered one of the widely studied essential oils while its leaves attract less attention although being rich in nearly the same composition as the peel and flowers. The leaves of bitter orange or sour orange (Citrus aurantium L.) were extracted using three different techniques namely; hydrodistillation (HD), steam distillation (SD), and microwave-assisted distillation (MV) to compare their chemical composition. The three essential oil samples were analyzed through GC/FID and GC/MS analyses. The samples were tested in vitro using different antioxidant techniques (DPPH, ABTS, CUPRAC, FRAP, PBD, and MCA), neuroprotective enzyme inhibitory activities (acetylcholine and butyl choline enzymes), and antidiabetic activities (α-amylase and α-glucosidase). The results showed that thirty-five volatile ingredients were detected and quantified. Monoterpenes represented the most abundant class in the three essential oils followed by sesquiterpenes. C. aurantium essential oil carried potential antioxidant activity where SD exhibited the highest antioxidant activity, with values arranged in the following order: FRAP (200.43 mg TE/g), CUPRAC (138.69 mg TE/g), ABTS (129.49 mg TE/g), and DPPH (51.67 mg TE/g). SD essential oil also presented the most potent α-amylase (0.32) inhibition while the MV essential oil showed the highest α-glucosidase inhibition (2.73 mmol ACAE/g), followed by HD (2.53 mmol ACAE/g), and SD (2.46 mmol ACAE/g). The SD essential oil exhibited the highest BChE and AChE inhibitory activities (3.73 and 2.06 mg GALAE/g), respectively). Thus, bitter orange essential oil can act as a potential source of potent antioxidant, antidiabetic, and neuroprotective activities for future drug leads.

Anti-inflammatory and Antioxidant Activity of Cucumis sativus and Citrus macroptera Herbal Formulation: An In-Vitro Study.

Background The interest in natural remedies is increasing rapidly as they can serve as alternatives to synthetic drugs and reduce their potential side effects. Current research is focused on examining the antioxidant and anti-inflammatory characteristics of a combination of Cucumis sativus and Citrus macroptera extract in an in-vitro context. The combination of citrus, cucumber, and glycerol extract could serve as an effective alternative to synthetic antioxidants and anti-inflammatory drugs and lower the side effects of the available synthetic drugs. This extract can be used to treat potentially malignant oral disorders like oral leukoplakia, oral submucous fibrosis, and oral lichen planus, which are attributed to its antioxidant properties. Aim To evaluate the anti-inflammatory and antioxidant activity of formulation of C. sativus, C. macroptera, and glycerol extract. Materials and methods The cucumber and citrus fruits were separated, cleaned, and dried. The cucumber was then peeled, its seeds cleaned, and the pulp cut into pieces. Using a laboratory mortar and pestle, a 5 ml extract was prepared. The citrus fruit was cut in half, its seeds were removed, and a 5 ml extract was prepared from their pulp only. These two extracts were combined to form a 10 ml extract solution with 8 ml of glycerol. The extracts were combined, shaken for 24 hours, filtered, and stored at 4°C. Assays like the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, Hydrogen Peroxide (H2O2) assay, Bovine serum albumin (BSA) assay, and Egg albumin (EA) denaturation assay were performed to assess their anti-inflammatory and antioxidant properties. Results The antioxidant and anti-inflammatory properties of the extract showed comparable activity (percentage of inhibition: 76% in BSA and EA assays; 90% in DPPH and H2O2 assays) to that of the standard values (percentage of inhibition: 78% in BSA and EA assays; 92% in DPPH and H2O2 assays) at concentrations 30, 40, and 50 µl in the BSA assay, EA assay, DPPH, and H2O2 assay. The maximum concentration at which the antioxidant and anti-inflammatory effects were appreciable was 50 µl in all assays.  Conclusion This study concluded that the combination of cucumber, citrus, and glycerol extract could serve as an effective alternative to synthetic antioxidants and anti-inflammatory drugs currently available. These extracts can provide a promising solution in the field of drug development for treating lesions caused by free radicals and oxidative stress in the oral cavity.

Inhibition of Glial Activation and Subsequent Reduction in White Matter Damage through Supplementation with a Combined Extract of Wheat Bran, Citrus Peel, and Jujube in a Rat Model of Vascular Dementia.

Vascular dementia (VaD) is the second most common type of dementia after Alzheimer's disease. In our previous studies, we showed that wheat bran extract (WBE) reduced white matter damage in a rat VaD model and improved memory in a human clinical trial. However, starch gelatinization made the large-scale preparation of WBE difficult. To simplify the manufacturing process and increase efficacy, we attempted to find a decoction containing an optimum ratio of wheat bran, sliced citrus peel, and sliced jujube (WCJ). To find an optimal ratio, the cell survival of C6 (rat glioma) cultured under hypoxic conditions (1% O2) was measured, and apoptosis was assessed. To confirm the efficacies of the optimized WCJ for VaD, pupillary light reflex, white matter damage, and the activation of astrocytes and microglia were assessed in a rat model of bilateral common carotid artery occlusion (BCCAO) causing chronic hypoperfusion. Using a combination of both searching the literature and cell survival experiments, we chose 6:2:1 as the optimal ratio of wheat bran to sliced citrus peel to sliced jujube to prepare WCJ. We showed that phytic acid contained only in wheat bran can be used as an indicator component for the quality control of WCJ. We observed in vitro that the WCJ treatment improved cell survival by reducing apoptosis through an increase in the Bcl-2/Bax ratio. In the BCCAO experiments, the WCJ-supplemented diet prevented astrocytic and microglial activation, mitigated myelin damage in the corpus callosum and optic tract, and, consequently, improved pupillary light reflex at dosages over 100 mg/kg/day. The results suggest that the consumption of WCJ can prevent VaD by reducing white matter damage, and WCJ can be developed as a safe, herbal medicine to prevent VaD.

Boron-mediated amelioration of copper toxicity in Citrus sinensis seedlings involved reduced concentrations of copper in leaves and roots and their cell walls rather than increased copper fractions in their cell walls.

Little information is available on how boron (B) supplementation affects plant cell wall (CW) remodeling under copper (Cu) excess. 'Xuegan' (Citrus sinensis) seedlings were submitted to 0.5 or 350 µM Cu × 2.5 or 25 µM B for 24 weeks. Thereafter, we determined the concentrations of CW materials (CWMs) and CW components (CWCs), the degree of pectin methylation (DPM), and the pectin methylesterase (PME) activities and PME gene expression levels in leaves and roots, as well as the Cu concentrations in leaves and roots and their CWMs (CWCs). Additionally, we analyzed the Fourier transform infrared (FTIR) and X-ray diffraction (XRD) spectra of leaf and root CWMs. Our findings suggested that adding B reduced the impairment of Cu excess to CWs by reducing the Cu concentrations in leaves and roots and their CWMs and maintaining the stability of CWs, thereby improving leaf and root growth. Cu excess increased the Cu fractions in leaf and root pectin by decreasing DPM due to increased PME activities, thereby contributing to citrus Cu tolerance. FTIR and XRD indicated that the functional groups of the CW pectin, hemicellulose, cellulose, and lignin could bind and immobilize Cu, thereby reducing Cu cytotoxicity in leaves and roots.