Parallel evolution of UbiA superfamily proteins into aromatic O-prenyltransferases in plants.

Plants produce ∼300 aromatic compounds enzymatically linked to prenyl side chains via C-O bonds. These O-prenylated aromatic compounds have been found in taxonomically distant plant taxa, with some of them being beneficial or detrimental to human health. Although their O-prenyl moieties often play crucial roles in the biological activities of these compounds, no plant gene encoding an aromatic O-prenyltransferase (O-PT) has been isolated to date. This study describes the isolation of an aromatic O-PT gene, CpPT1, belonging to the UbiA superfamily, from grapefruit (Citrus × paradisi, Rutaceae). This gene was shown responsible for the biosynthesis of O-prenylated coumarin derivatives that alter drug pharmacokinetics in the human body. Another coumarin O-PT gene encoding a protein of the same family was identified in Angelica keiskei, an apiaceous medicinal plant containing pharmaceutically active O-prenylated coumarins. Phylogenetic analysis of these O-PTs suggested that aromatic O-prenylation activity evolved independently from the same ancestral gene in these distant plant taxa. These findings shed light on understanding the evolution of plant secondary (specialized) metabolites via the UbiA superfamily.

Role of hydraulic traits in stomatal regulation of transpiration under different vapour pressure deficits across five Mediterranean tree crops.

The differential stomatal regulation of transpiration among plant species in response to water deficit is not fully understood, although several hydraulic traits have been reported to influence it. This knowledge gap is partly due to a lack of direct and concomitant experimental data on transpiration, stomatal conductance, and hydraulic traits. We measured sap flux density (Js), stomatal conductance (gs), and different hydraulic traits in five crop species. Our aim was to contribute to establishing the causal relationship between water consumption and its regulation using a hydraulic trait-based approach. The results showed that the species-specific regulation of Js by gs was overall coordinated with the functional hydraulic traits analysed. Particularly relevant was the negative and significant relationship found between the Huber value (Hv) and its functional analogue ratio between maximum Js and gs (Jsmax/gsmax) which can be understood as a compensation to maintain the hydraulic supply to the leaves. The Hv was also significantly related to the slope of the relationship between gs and Js response to vapour pressure deficit and explained most of its variability, adding up to evidence recognizing Hv as a major trait in plant water relations. Thus, a hydraulic basis for regulation of tree water use should be considered.

Preparation of Acetylated Grapefruit Peel Polysaccharide.

Grapefruit peel polysaccharide has antioxidant, antitumor, hypoglycemic and other biological activities, and chemical modification can further improve the properties of the polysaccharide. Acetylation modification of polysaccharides has the advantages of simple operation, low cost and little pollution, and is widely used at present. Different degrees of acetylation modification have different effects on the properties of polysaccharides, so it is necessary to optimize the preparation technology of acetylated grapefruit peel polysaccharides. In this article, acetylated grapefruit peel polysaccharide was prepared by acetic anhydride method. With the degree of acetyl substitution as the evaluation index, combined with the analysis of sugar content and protein content in the polysaccharide before and after modification, the effects of three feeding ratios of 1:0.6, 1 : 1.2 and 1 : 1.8 (polysaccharide: acetic anhydride, mass/volume) on acetylation modification were explored through single factor experiments. The results showed that the optimum ratio of material to liquid for acetylation modification of grapefruit peel polysaccharide was 1:0.6. Under these conditions, the degree of substitution of acetylated grapefruit peel polysaccharide was 0.323, the sugar content was 59.50 % and the protein content was 1.038 %. The results provide some reference for the study of acetylated grapefruit peel polysaccharide.

First report of grapefruit rot caused by Colletotrichum gloeosporioides and C. karsti in France.

The grapefruit (Citrus paradisi) is a citrus hybrid tree (C. maxima & C. sinensis). Due to nutritional value and its bioactive compounds, the fruits are recognized as a functional food, valued as promoting health. French grapefruit production is low (7.5 Kt/year) but is confined to a restricted area in Corsica and benefits from a quality label, the economic impact of its cultivation being therefore locally significant. Since 2015 previously unreported symptoms have been repeatedly observed on grapefruits in more than half of the orchards in Corsica, with an incidence of 30% of fruits altered. Brown to black circular spots were observed on fruits and leaves, surrounded by chlorotic halos on the latter. On the mature fruit, lesions were round, 4 to 10 mm in diameter, brown and dry (e-Xtra 1). Although the lesions are superficial, the fruits cannot be marketed due to constraints linked to the quality label. 75 fungal isolates were obtained from symptomatic fruits or leaves collected in Corsica (in 2016, 2017, and 2021). Cultures obtained after 7 days on PDA at 25°C, were white to light grey in colour, forming concentric rings or dark spots on the agar surface. We did not observe any notable difference among the isolates except some evolved towards a more marked grey. Colonies tend to form a cottony aerial mycelium and orange conidial masses appear with age. The conidia were hyaline, aseptate, cylindrical with ends rounded, and measured 14.9 ± 0.95 µm length and 5.1 ± 0.45 µm width (n = 50). Cultural and morphological characteristics were similar to those described for C. gloeosporioides s. lat. or C. boninense s. lat. (Weir et al. 2012 ; Damm et al. 2012). Total genomic DNA was extracted from all isolates, and the ITS region of rDNA was amplified with ITS 5 & 4 primers, then sequenced (GenBank Accession Nos. OQ509805-808). For 90% of isolates GenBank BLASTn results were 100% identical to C. gloeosporioides isolates sequences, whereas for other isolates the resulting sequences were 100% identical to C. karsti or C. boninense isolates sequences. Four strains (three C. gloeosporioides with light colour differences, in order to see if there was diversity among isolates of C. gloeosporioides s. lato ; and one C. karsti) were further characterized by sequencing partial actin [ACT], calmodulin [CAL], chitin synthase [CHS-1], glyceraldehyde-3-phosphate dehydrogenase [GAPDH], ß-tubulin 2 [TUB2], for all strains ; glutamine synthetase [GS], Apn2-Mat1-2-1 intergenic spacer and partial mating type (Mat1-2) gene [ApMAT] for C. gloeosporioides s. lat., and HIS3 for C. boninense s. lat. (Weir et al. 2012 ; Silva et al, 2012) (GenBank Accession Nos. OQ509805-808 & OQ507698-724). Multilocus phylogenetic analyses carried out with the obtained and Genbank available sequences confirmed that 3 isolates (UBOCC-A-116036, -116038, & -116039) clustered within C. gloeosporioides s. s., while the other (UBOCC-A-116037) clustered within C. karsti (e-Xtra 2) 'Star ruby' grapefruits were surface sterilized then wound-inoculated with 20 µl of a conidial suspension (105 conidia ml-1) of UBOCC-A-116036 & 116037 isolates or 20 µl sterile water for control (ten fruits for each isolate or control). After 10 days incubation at 20°C, symptoms, identical to those initially observed, developed around the inoculation point, while controls inoculated with water remained symptomless. Fungal colonies re-isolated from the lesions were morphologically like the original isolates. Recently, various infections caused by some Colletotrichum sp. have strongly compromised citrus production in different Mediterranean countries: ie Italy (Aiello et al. 2015), Portugal (Ramos et al. 2016), Tunisia (Ben Hadj Daoud et al. 2019), Turkey (Uysal et al. 2022). In these studies, C. gloeosporioides s. s. and C. karsti were identified as the causal agents. These two species were the predominant Colletotrichum sp. associated with Citrus and allied genera in Europe (Guarnaccia et al. 2017). To our knowledge, our study is the first report of C. gloeosporioides and C. karsti causing anthracnose on grapefruit in France, which confirms the incidence of these two pathogens on the Mediterranean rim. Given the economic importance of citrus cultivation in the Mediterranean region, the presence of Colletotrichum spp. should deserves to be monitored, and a control strategy should be considered.

Ex Vivo Anti-Leukemic Effect of Exosome-like Grapefruit-Derived Nanovesicles from Organic Farming-The Potential Role of Ascorbic Acid.

Citrus fruits are a natural source of ascorbic acid, and exosome-like nanovesicles obtained from these fruits contain measurable levels of ascorbic acid. We tested the ability of grapefruit-derived extracellular vesicles (EVs) to inhibit the growth of human leukemic cells and leukemic patient-derived bone marrow blasts. Transmission electron microscopy and nanoparticle tracking analysis (NTA) showed that the obtained EVs were homogeneous exosomes, defined as exosome-like plant-derived nanovesicles (ELPDNVs). The analysis of their content has shown measurable amounts of several molecules with potent antioxidant activity. ELPDNVs showed a time-dependent antiproliferative effect in both U937 and K562 leukemic cell lines, comparable with the effect of high-dosage ascorbic acid (2 mM). This result was confirmed by a clear decrease in the number of AML blasts induced by ELPDNVs, which did not affect the number of normal cells. ELPDNVs increased the ROS levels in both AML blast cells and U937 without affecting ROS storage in normal cells, and this effect was comparable to ascorbic acid (2 mM). With our study, we propose ELPDNVs from grapefruits as a combination/supporting therapy for human leukemias with the aim to improve the effectiveness of the current therapies.

Bioavailability of Bioactive Compounds from Reconstituted Grapefruit Juice as Affected by the Obtention Process.

Much attention has been paid to the health benefits of including fruits and vegetables in the diet. However, for the compounds responsible for this beneficial effect to be effective at the level of the human organism, they must be available for absorption after digestion. In this sense, in vivo studies are needed to demonstrate the bioavailability of these compounds and their physiological activity. In order to provide information in this regard, this study collects data on the levels of vitamin C (VC) and naringenin (NAG) in the blood serum of the 11 volunteer participants in this trial, before and after consuming two different grapefruit juices. The juices were prepared by rehydrating the grapefruit powder obtained by freeze-drying (FD) the fruit puree or by spray-drying (SD) the liquefied grapefruit. No significant differences (p > 0.05) neither by juice nor by participant were observed in any case. The mean relative increase of VC, NAG and the radical scavenging ability (RSA) in blood serum due to grapefruit juices intake was 12%, 28% and 26%, respectively. Just VC showed a positive and significant Pearson's correlation with RSA. The mean bioavailability of VC was quantified as 1.529 ± 0.002 mg VC/L serum per 100 mg of VC ingested.

Modeling the relationship between air temperature and grapefruit quality traits.

BACKGROUND: Consumers of grapefruit require consistent fruit quality with a good physical appearance and taste. The air temperature during the growing season affects both the external (external color index (ECI)) and internal (titratable acidity (TA) and total soluble solids ratio (TSS/TA)) fruit quality of grapefruit. The objective of this study was to develop computer models that encompass the relationship between preharvest air temperature and fruit quality to predict fruit quality of grapefruit at harvest. RESULTS: There was a logarithmic relationship between the number of days with a daily minimum air temperature ≤13 °C and ECI, with a greater number of days resulting in higher ECI. In addition, there was a second-order polynomial relationship between the number of hours ≥21 °C and both TA and TSS/TA, with a greater number of hours resulting in lower TA and higher TSS/TA. Model performance for predicting the ECI, TA, and TSS/TA during 2004-05 and 2005-06 growing seasons was good, with Nash and Sutcliffe coefficient of efficiency (NSE) values for each season of 0.835 and 0.917 respectively for ECI, 0.896 and 0.965 respectively for TA and 0.898 and 0.966 respectively for TSS/TA. Applying the model to statistical survey data covering 13 growing seasons demonstrated that the TSS/TA model was robust. CONCLUSION: Statistical models were developed that predicted the development of grapefruit ECI, TA, and TSS/TA. The TSS/TA model was confirmed after application to long-term statistical survey data covering 13 growing seasons. © 2022 Society of Chemical Industry.

Randomized Controlled Study in the Use of Aromatherapy for Pain Reduction and to Reduce Opioid Use in the Emergency Department.

INTRODUCTION: This study aimed to evaluate the effects of aromatherapy on emergency department patients' perception of pain and its ability to reduce the use of opioids in an emergency department. METHODS: This randomized, controlled, single-blinded study was conducted in a suburban/rural freestanding emergency department with a therapeutic group, sham group, and control group. RESULTS: A total of 230 patients, 171 females and 59 males, completed the study. Of those who received the therapeutic agent, an average reduction in pain of 1.04 points on the pain scale was reported, whereas the sham group averaged 0.38 and the control group 0.23. There was a statistically significant reduction of pain scores in the therapeutic group. A total of 13 received opioid pain medication during their visit. Of these, the therapeutic group averaged a total of 2.67 morphine milligram equivalents for their visit compared with 3.63 in the sham group and 4.36 in the control group; however, statistical significance was not achieved. DISCUSSION: This study supported what other studies have found, indicating that aromatherapy is effective in reducing pain. A difference between the placebo effect and a true therapeutic effect was seen by using a control group apart from the sham and therapeutic groups. Despite the small effect size (0.3), implementation of aromatherapy into standard practice may be practical considering the anxiolytic effects that have been shown in other studies. Aromatherapy with essential oils should be considered as another tool to use in a multimodal approach in the treatment of pain in the emergency department setting.

Examining the Naringin Content and Sensory Characteristics of Functional Chocolate Fortified with Grapefruit Peel Extract.

Grapefruit peel contains a high concentration of naringin- a potent antioxidant with strong bioactive properties. In this study, a new type of functional chocolate fortified with grapefruit peel extract and different concentrations of aqueous methanol and ethanol were evaluated as extraction solvents. A new high-performance liquid chromatography (HPLC) method to analyze the naringin content of the fortified chocolates was developed with a recovery of 107% ± 3.1% and repeatability below 3.5%. A sensory evaluation was conducted to assess the preference for the chocolates among individuals who self-described a preference for bitter flavors. No significant preference was observed in the cases of astringency and aftertaste while the increased bitterness proved to be favorable. However, taste, flavor and overall acceptability were regarded somewhat less favorably. While chocolate proved to be a satisfactory carrier for naringin and had several enjoyable characteristics, further research may focus on improving the organoleptic properties of chocolates fortified by naringin.

Outgoing and potential trends of composition, health benefits, juice production and waste management of the multi-faceted Grapefruit Citrus Χ paradisi: A comprehensive review for maximizing its value.

Grapefruit (GF) Citrus Χ paradisi Macfad (F. Rutaceae) is one of the major citrus fruits that encompass a myriad of bioactive chemicals and most unique among citrus fruits. Nevertheless, no study has yet to assess comprehensively its multitudinous constituents, health benefits, and valuable waste products. Hereto, the present review provides an updated comprehensive review on the different aspects of GF, its juice production, waste valorization, enhancement of its byproducts quality, and compared to other citrus fruits. Grapefruit uniqueness among other citrus fruits stands from its unique taste, flavor, and underlying complex chemical composition. Despite limonene abundance in peel oil and grapefruit juice (GFJ) aroma, nootkatone and sulfur compounds are the key determinants of its flavor, whereas flavanones contribute to its bitter taste and in conjunction with limonoids. Different postharvest treatments and juice processing are reviewed and in context to its influence on final product quality and or biological effects. Flavanones, furanocoumarins, and limonoids appear as the most prominent in GF drug interactions affecting its metabolism and or excretion. Valorization of GF peel is overviewed for its utilization as biosrobent, its oil in aromatherapy, limonene as antimicrobial or in cosmetics, fruit pectin for bioethanol production, or as biosorbent, and peel phenolics biotransformation. The present review capitalizes on all of the aforementioned aspects in GF and further explore novel aspects of its juice quality presenting the full potential of this valued multi-faceted citrus fruit.

Antifungal activity of Zinc nitrate derived nano Zno fungicide synthesized from Trachyspermum ammi to control fruit rot disease of grapefruit.

Grapefruit (Citrus paradisi) is a widely grown citrus and its fruit is affected by a variety of biotic and abiotic stress. Keeping in view the hazardous effects of synthetic fungicides, the recent trend is shifting towards safer and eco-friendly control of fruit diseases. The present study was aimed to diagnose the fruit rot disease of grapefruit and its control by using zinc oxide green nanoparticles (ZnO NPs). Fruit rot symptoms were observed in various grapefruit growing sites of Pakistan. Diseased samples were collected, and the disease-causing pathogen was isolated. Following Koch's postulates, the isolated pathogen was identified as Rhizoctonia solani. For eco-friendly control of this disease, ZnO NPs were prepared in the seed extract of Trachyspermum ammi and characterized. Fourier transform infrared spectroscopy (FTIR) of these NPs described the presence of stabilizing and reducing compounds such as phenols, aldehyde and vinyl ether, especially thymol (phenol). X-ray diffraction (XRD) analysis revealed their crystalline nature and size (48.52 nm). Energy dispersive X-ray (EDX) analysis elaborated the presence of major elements in the samples, while scanning electron microscopy (SEM) confirmed the morphology of bio fabricated NPs. ZnO NPs exhibited very good anti-fungal activity and the most significant fungal growth inhibition was observed at 1.0 mg/ml concentration of green NPs, in vitro and in vivo. These findings described that the bioactive constituents of T. ammi seed extract can effectively reduce and stabilize ZnO NPs. It is a cost-effective method to successfully control the fruit rot disease of grapefruit.

Core shell stationary phase for a novel separation of some COVID-19 used drugs by UPLC-MS/MS Method: Study of grapefruit consumption impact on their pharmacokinetics in rats.

A sensitive and selective UPLC-MS/MS method was developed for the synchronized determination of four drugs used in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), namely, azithromycin, apixaban, dexamethasone, and favipiravir in rat plasma. using a Poroshell 120 EC-C18 column (50 mm × 4.6 mm, 2.7 m) with a high-resolution ESI tandem mass spectrometer detection with multiple reaction monitoring. We used an Agilent Poroshell column, which is characterized by a stationary phase based on non-porous core particles. With a remarkable improvement in the number of theoretical plates and low column backpressure. In addition, the developed method was employed in studying the potential food-drug interaction of grapefruit juice (GFJ) with the selected drugs which affects their pharmacokinetics in rats. The LC-MS/MS operated in positive and negative ionization mode using two internal standards: moxifloxacin and chlorthalidone, respectively. Liquid- liquid extraction of the cited drugs from rat plasma was accomplished using diethyl ether: dichloromethane (70:30, v/v). The analytes were separated using methanol: 0.1 % formic acid in water (95: 5, v/v) as a mobile phase in isocratic mode of elution pumped at a flow rate of 0.3 mL/min. A detailed validation of the bio-analytical method was performed in accordance with US-FDA and EMA guidelines. Concerning the in vivo pharmacokinetic study, the statistical significance between the results of the test groups receiving GFJ along with the cited drugs and the control group was assessed demonstrating that GFJ increased the plasma concentration of azithromycin, apixaban, and dexamethasone. Accordingly, this food-drug interaction requires cautious ingestion of GFJ in patients using (SARS-CoV-2) medications as it can produce negative effects in the safety of the drug therapy. A potential drug-drug interaction is also suggested between those medications requiring a suitable dose adjustment.

Protective Effects of Grapefruit Essential Oil against Staphylococcus Aureus-Induced Inflammation and Cell Damage in Human Epidermal Keratinocytes.

Staphylococcus aureus (S. aureus) is a common skin pathogenic bacterium, over-colonization can induce skin infections, while its metabolites can also produce irritation to the skin, often accompanied by eczema dermatitis, specific dermatitis and other skin diseases. Grapefruit essential oil is extracted from the fruit of grapefruit (Citrus maxima (Burm) Merr.), a citrus plant that is rich in flavonoids, phenolic acids and high flavanones. Due to its good odor and biological activity such as anti-inflammatory, antibacterial, etc., grapefruit essential oil has been widely used as an additive in food. To evaluate the potential application of grapefruit essential oil as raw materials in cosmetics products and health foods, we developed a cell damage model of skin inflammation stimulated by S. aureus metabolites. Compared to that of lime essential oil, an internal control, we found that grapefruit essential oil could significantly promote HaCaT cells proliferation, reduce reactive oxygen species (ROS) production induced by S. aureus metabolites, inhibit the upregulated expression of IL-1 and COX-2. In the 3D epidermal model, grapefruit essential oil could recover the decreased LOR and FLG contents caused by S. aureus metabolites. These results demonstrated pharmacological evidence for the anti-inflammatory effect of grapefruit essential oil, suggesting a potential application of grapefruit essential oil as cosmetic raw materials for repair and alleviating of skin inflammation caused by S. aureus.

A Biomimetic Drug Delivery System by Integrating Grapefruit Extracellular Vesicles and Doxorubicin-Loaded Heparin-Based Nanoparticles for Glioma Therapy.

Existing nanoparticle-mediated drug delivery systems for glioma systemic chemotherapy remain a great challenge due to poor delivery efficiency resulting from the blood brain barrier/blood-(brain tumor) barrier (BBB/BBTB) and insufficient tumor penetration. Here, we demonstrate a distinct design by patching doxorubicin-loaded heparin-based nanoparticles (DNs) onto the surface of natural grapefruit extracellular vesicles (EVs), to fabricate biomimetic EV-DNs, achieving efficient drug delivery and thus significantly enhancing antiglioma efficacy. The patching strategy allows the unprecedented 4-fold drug loading capacity compared to traditional encapsulation for EVs. The biomimetic EV-DNs are enabled to bypass BBB/BBTB and penetrate into glioma tissues by receptor-mediated transcytosis and membrane fusion, greatly promoting cellular internalization and antiproliferation ability as well as extending circulation time. We demonstrate that a high-abundance accumulation of EV-DNs can be detected at glioma tissues, enabling the maximal brain tumor uptake of EV-DNs and great antiglioma efficacy in vivo.

Grapefruit Debittering by Simultaneous Naringin Hydrolysis and Limonin Adsorption Using Naringinase Immobilized in Agarose Supports.

Naringin and limonin are the two main bitter compounds of citrus products such as grapefruit juice. The aim of this investigation was to evaluate the reduction in both bitter components simultaneously using a combined biochemical and physical approach. The proposed strategy was based on the use of heterofunctional supports with glyoxyl groups that allow for the covalent immobilization of naringinase, which hydrolyses naringin and alkyl groups that allow for the adsorption of limonin. The supports were butyl-glyoxyl agarose (BGA) and octyl-glyoxyl agarose (OGA), which were characterized in terms of aldehyde group quantification and FTIR analysis. The optimal pH and temperature of free and immobilized enzymes were assessed. The maximum enzyme loading capacity of supports was analyzed. Debittering of grapefruit juice was evaluated using soluble enzyme, enzyme-free supports, and immobilized catalysts. Enzyme immobilized in BGA reduced naringin and limonin concentrations by 54 and 100%, respectively, while the use of catalyst immobilized in OGA allowed a reduction of 74 and 76%, respectively, obtaining a final concentration of both bitter components under their detection threshold. The use of OGA biocatalyst presented better results than when soluble enzyme or enzyme-free support was utilized. Biocatalyst was successfully applied in juice debittering in five repeated batches.

Naringinase Biosynthesis by Aspergillus niger on an Optimized Medium Containing Red Grapefruit Albedo.

This study aimed to develop a method of naringinase biosynthesis by Aspergillus niger KMS on an optimized culture medium. The concentration of the six medium components in shake flasks was optimized by the Box and Wilson factor gradient method. Naringinase's substrate, naringin, powdered albedo, flavedo, and red grapefruit segment membranes were used to stimulate naringinase biosynthesis. Rhamnose was chosen as the carbon source, while the nitrogen source was yeast extract and sodium nitrate. Naringinase biosynthesis was most favorable in the culture medium with the following composition (g 100 mL): 3.332-NaNO3; 3.427-yeast extract; 0.184-KH2PO4; 0.855-red grapefruit albedo; 0.168-naringin; 2.789-rhamnose. The obtained Aspergillus niger KMS culture fluid was concentrated, thereby precipitating the protein. As a result, a naringinase preparation with high activity, equal to 816 µmol × min-1 × g-1, was obtained.

Chemical Profiling, Toxicity and Anti-Inflammatory Activities of Essential Oils from Three Grapefruit Cultivars from KwaZulu-Natal in South Africa.

The medicinal potential and volatile composition of different parts of three cultivars of grapefruit (Citrus paradisi) were evaluated for their toxicity and anti-inflammatory activities. Fresh leaf and fruit peel were separately isolated by hydrodistillation for 4 h. The essential oils were subjected to GC/GC-MS analysis for chemical profile. Toxicity of the essential oils in mice were evaluated using Lorke's method, while an anti-inflammatory assay was performed in a rat model using egg albumin-induced oedema. The oils obtained were light yellow in colour, and odour varied from strong citrus smell to mild. Percentage yield of fresh peel oil (0.34-0.57%) was greater than the fresh leaf oil yield (0.21-0.34%). D-limonene (86.70-89.90%) was the major compound identified in the leaf oil, while ß-phellandrene (90.00-91.01%) dominated the peel oil. At a dosage level of 5000 mg/kg, none of the oils showed mortality in mice. An anti-inflammatory bioassay revealed that all the oils caused a significant (p < 0.05-0.01) reduction in oedema size when compared to the negative control group throughout the 5 h post induction assessment period. The study reveals that the oils are non-toxic and demonstrate significant anti-inflammatory activity. Our findings suggest that the leaf and peel oils obtained from waste parts of grapefruit plants can be useful as flavouring agents, as well as anti-inflammatory agents.

CytroCell: Valued Cellulose from Citrus Processing Waste.

Isolating cellulose from citrus processing waste without employing chemicals has so far been an unfulfilled goal of chemical research applied to the valorization of a widely available biowaste, annually totaling >100 million tonnes. We have applied hydrodynamic cavitation using a Venturi-type reactor for the extraction of all valued bioproducts of industrial citrus processing waste in water only, directly on a semi-industrial scale. After reporting the discovery of IntegroPectin in the soluble fraction of the aqueous extract, we now report the isolation of a cellulosic material in the water-insoluble fraction of cavitated lemon and grapefruit processing waste. Named "CytroCell", the material is cellulose of low crystallinity, high porosity, good water holding capacity and good dispersibility in water. These properties open the route to mass-scale production of a useful functional material from a cheap and abundant biowaste.

Comparison of microwave-assisted techniques for the extraction of antioxidants from Citrus paradisi Macf. biowastes.

Microwave-assisted extraction (MAE) and solvent-free microwave extraction and Soxhlet extraction were applied to Ray Ruby grapefruit leaves (Citrus paradisi Macf.) to compare extract efficiency. Face centered composite designs were constructed via response surface methodology. Effects of factors of MAE were investigated on total phenolic content (TPC) and naringin content (NC). The optimized conditions were established as 1.4 kWL-1 for microwave power density, 20.00 gL-1 for solid/solvent ratio, 218.180 s for extraction time, while responses were calculated as 14.210 mg of gallic acid equivalent per g of the dried leaf (mg GAE g-1DL) and 13.198 mg of naringin per g of dried leaf (mg Ng-1DL) for TPC and NC, respectively. SFME and classical Soxhlet methods were also conducted for comparison reasons.

Chimeric cytochrome P450 3A4 used for in vitro prediction of food-drug interactions.

Inhibition of cytochrome P450 (CYP)-mediated drug metabolism by dietary substances is the main cause of drug-food interactions in humans. The present study reports on the in vitro inhibition assays of human CYP3A4 genetically linked to the reductase domain of bacterial BM3 of Bacillus megaterium (BMR) resulting in the chimeric protein CYP3A4-BMR. The activity of this chimeric enzyme was initially measured colorimetrically with erythromycin as the substrate where KM values similar to published data were determined. Subsequently, the inhibition assays with three different dietary products, grapefruit juice, curcumin, and resveratrol, were carried out with the chimeric enzyme both in solution and immobilized on electrode surfaces. For the solution studies, nicotinamide adenine dinucleotide phosphate was added as the electron donor, whereas the need for this cofactor was obviated in the immobilized enzyme as it was supplied by the electrode. Inhibition of the N-demethylation of erythromycin by CYP3A4-BMR chimera was measured at increasing concentrations of the different dietary compounds with calculated IC50 values of 0.5%, 31 µM, and 250 µM for grapefruit juice, curcumin, and resveratrol measured in solution compared with 0.7%, 24 µM, and 208 µM measured electrochemically, respectively. These data demonstrate the feasibility of the use of both CYP3A4-BMR chimera as well as bioelectrochemistry for in vitro studies of not only drug-food interactions but also prediction of adverse drug reactions in this important P450 enzyme.