Search Results (24)

Bitter orange (Citrus aurantium L.), a member of the Rutaceae family, finds global utility in both the treatment of various ailments and its role as a rootstock for Citrus species in agriculture. Various parts of Citrus aurantium L. have been employed in traditional medicine due to their multifarious therapeutic potential. The blossom of this plant serves as a rich source of bioactive compounds, notably polyphenols, alkaloids, and terpenes. Additionally, it harbors substantial quantities of functional, nutritive, and biologically active compounds, which manifest their presence through antioxidant, antidiabetic, anticancer, antimicrobial, cardiovascular, and neuroprotective properties. The recovery of bioactive compounds is significantly affected by extraction methods. Many conventional methods have been explored for the recovering of bioactive compounds from bitter orange flowers. However, in response to the limitations of conventional techniques, green extraction methods, characterized by their ability to significantly increase the yield and reduce the time, energy, and solvent requirements, have also been assessed for this matrix. Therefore, the study of the functionalities of bitter orange blossoms represents a domain with unexplored research opportunities. Consequently, this review aims to offer a comprehensive insight into the biological properties and medicinal applications of the active compounds found within C. aurantium. Full article

This review provides an overview of recent developments in Citrus aurantium L. (sour or bitter orange), focusing on its bioactive compounds, innovative extraction techniques, and technological applications. C. aurantium is rich in bioactive compounds such as flavonoids (naringin, hesperidin, kaempferol, quercetin), essential oils (β-pinene, limonene), and vitamin C, which represents significant biological activities including antioxidant, antimicrobial, anti-inflammatory, and anticancer effects. The review discusses traditional extraction methods, such as solvent extraction and hydrodistillation, alongside newer, eco-friendly approaches like ultrasound-assisted extraction, microwave-assisted extraction, supercritical fluid extraction, and natural deep eutectic solvents. It also highlights cutting-edge techniques, including molecular imprinting polymer-based extraction, which enable the more efficient enrichment and purification of specific compounds like synephrine. Finally, the review examines the diverse industrial applications of these bioactive compounds in sectors such as foods, pharmaceuticals, and cosmetics, while emphasizing the growing need for sustainable and efficient extraction technologies. Full article

Citrus fruits are widely consumed worldwide; however, one of their primary uses is juice production, resulting in over 40 million tons of agro-industrial waste. Citrus peel is the main agro-industrial by-product in citrus production. In recent years, secondary metabolites of interest, mainly polyphenols such as hesperidin, have been identified in citrus peels. Currently, green alternatives like natural deep eutectic solvents (NADES) based on choline chloride and glucose (Glu), combined with ultrasound-assisted extraction, are studied to obtain polyphenol-rich extracts with potential health applications. This study aims to evaluate the effect of: (1) molar ratios (MR) of 1:0.5, 1:1 or 1:2 mol/mol of choline chloride (ChCl):glucose (Glu); (2) the percentage of added water (WA: 50, 60 or 70%) to NADES; and (3) different citrus peels of Citrus aurantium (bitter orange), Citrus sinensis (sweet orange), and Citrus limon (lemon) used for extraction, on polyphenol profiles, total polyphenol content (TPC), and antioxidant capacity (Ax) of the extracts. The extracts were analyzed using ultra-performance liquid chromatography (UPLC) and evaluated using the Folin–Ciocalteu method for TPC and DPPH assay for quantifying AC. A factorial experimental design 3³ was implemented. The extract obtained with an MR of 1:1 (ChCl:Glu) from Citrus aurantium peel exhibited the highest concentration of hesperidin (2003.37 ± 10.91 mg/100 g dry mass), whereas an MR of 1:2 (ChCl:Glu) exhibited the highest concentration of neohesperidin (1045.94 ± 1.27 mg/100 g dry mass), both using 60% WA. This extract also showed the highest antioxidant capacity, achieving 100% inhibition. On the other hand, the highest concentration of total phenolic content (TPC) (96.23 ± 0.83 mg GAE/100 g dry mass) was obtained using C. aurantium peel with an MR of 1:0.5 (ChCl:Glu) and 60% WA. The extracts also presented high concentrations of rutin and catechin. These findings highlight the potential of revalorizing citrus peels, particularly Citrus aurantium, and their extracts obtained with NADES for possible health applications. Full article

Plant essential oils (EOs) and their active compounds are recognized as sustainable tools for the management of arthropod pests. The bitter orange, Citrus aurantium L. (Rutaceae), is a widespread tree in the Mediterranean region that is used especially as a rootstock for other Citrus. Although most of this plant’s parts are accredited with medicinal properties, its fruits are not consumable and generally considered as non-valued waste. The aim of this work was to assess the potential use of the EO extracted by hydrodistillation from C. aurantium peel in the fumigation of chickpea seeds against Calloosbruchus maculatus. Analysis of EO of the bitter orange peel by gas chromatography coupled with a mass spectrometer (GC-MS) identified twenty-two compounds with limonene as the major component (86%). EOs of C. aurantium peel exerted toxic effects, in a concentration-dependent manner, on eggs (LC₅₀ = 62.7 µL/L air), larval stages inside the seed (LC₅₀ = 62.8 µL/L air), and adults (females: LC₅₀ = 148 μL/L air and males: LC₅₀ = 109 µL/L air). The C. aurantium EO also negatively affected the biological and demographic performances of the weevil compared to the untreated control. Fecundity and the number of emerged adults were reduced by more than 57 and 71, respectively, while the net reproduction rate and the intrinsic rate of increase were respectively decreased by over 71% and 37%, resulting in the total extinction of the pest at a concentration equal to 100 µL/L air. Our findings suggest the possible valorization of bitter orange peel by using them as a source of bioinsecticide to be integrated within sustainable programs for the management of stored product pests. Further studies are needed to verify similar uses of essential oils extracted from solid wastes from citrus-processing industries. Full article

p-Synephrine is the principal alkaloid of bitter orange (Citrus aurantium). Several recent investigations have found that the intake of 2–3 mg/kg of p-synephrine raises fat oxidation rate during exercise of low-to-moderate intensity. However, these investigations have been carried out only with samples of male participants or mixed men/women samples. Therefore, the aim of this investigation was to study the effect of p-synephrine intake on fat oxidation during exercise of increasing intensity in healthy women. Using a double-blind, randomized experiment, 18 healthy recreationally active women performed two identical exercise trials after the ingestion of (a) 3 mg/kg of p-synephrine and (b) 3 mg/kg of a placebo (cellulose). The exercise trials consisted of a ramp test (from 30 to 80% of maximal oxygen uptake; VO₂max) on a cycle ergometer while substrate oxidation rates were measured at each workload by indirect calorimetry. In comparison to the placebo, the intake of p-synephrine increased resting tympanic temperature (36.1 ± 0.5 vs. 36.4 ± 0.4 °C p = 0.033, d = 0.87) with no effect on resting heart rate (p = 0.111) and systolic (p = 0.994) and diastolic blood pressure (p = 0.751). During exercise, there was no significant effect of p-synephrine on fat oxidation rate (F = 0.517; p = 0.484), carbohydrate oxidation rate (F = 0.730; p = 0.795), energy expenditure rate (F = 0.480; p = 0.833), heart rate (F = 4.269; p = 0.068) and participant’s perceived exertion (F = 0.337; p = 0.580). The maximal rate of fat oxidation with placebo was 0.26 ± 0.10 g/min and it was similar with p-synephrine (0.28 ± 0.08 g/min, p = 0.449, d = 0.21). An acute intake of 3 mg/kg of p-synephrine before exercise did not modify energy expenditure and substrate oxidation during submaximal aerobic exercise in healthy active women. It is likely that the increase in resting tympanic temperature induced by p-synephrine hindered the effect of this substance on fat utilization during exercise in healthy active women. Full article

Synephrine has been used to promote weight loss; however, its safety and efficacy have not been fully established. The goals of our study were to give an overview of the safety and efficacy of p-synephrine, to systematically evaluate its efficacy regarding weight loss and to assess its safety, focusing on its cardiovascular side effects in a meta-analysis. PubMed, the Cochrane Library, Web of Science and Embase were searched for relevant studies. Only placebo-controlled, human clinical trials with synephrine intervention were included in the meta-analysis. The meta-analysis was reported according to the PRISMA guidelines using the PICOS format and taking into account the CONSORT recommendations. Altogether, 18 articles were included in the meta-analysis. Both systolic and diastolic blood pressure (DBP) increased significantly after prolonged use (6.37 mmHg, 95% CI: 1.02–11.72, p = 0.02 and 4.33 mmHg, 95% CI: 0.48–8.18, p = 0.03, respectively). The weight loss in the synephrine group was non-significant after prolonged treatment, and it did not influence body composition parameters. Based on the analyzed clinical studies, synephrine tends to raise blood pressure and heart rate, and there is no evidence that synephrine can facilitate weight loss. Further studies are needed to confirm evidence of its safety and efficacy. Full article

DRIFT, HPLC-MS, and SPME-GC/MS analyses were used to unveil the structure and the main functional compounds of red (blood) orange (Citrus sinensis) and bitter orange (Citrus aurantium). The IntegroPectin samples show evidence that these new citrus pectins are comprised of pectin rich in RG-I hairy regions functionalized with citrus biophenols, chiefly flavonoids and volatile molecules, mostly terpenes. Remarkably, IntegroPectin from the peel of fresh bitter oranges is the first high methoxyl citrus pectin extracted via hydrodynamic cavitation, whereas the red orange IntegroPectin is a low methoxyl pectin. C. aurantium IntegroPectin has a uniquely high concentration of adsorbed flavonoids, especially the flavanone glycosides hesperidin, naringin, and eriocitrin. Full article

Spain is one of the most important producers of lemon fruits in the world (1,250,000 Tm in 2020/2021). In addition, about 80% of the Spanish production of lemons is located in the arid southeast, where fertirrigation is important to ensure the highest productivity. The aim of the present study was to determine the content of nutrients present in two differently grafted lemon trees (Citrus × limon) of the Verna variety, located on a drip-irrigation farm in Librilla (Region of Murcia, Spain). The first one was grafted in a Sweet orange rootstock (Citrus × sinensis), and the second one was grafted in a Bitter orange rootstock (Citrus × aurantium). Both were in 40-year-old trees grown in conventional agricultural practices. The Bitter orange rootstock (Citrus × aurantium) favoured the appearance of the ‘Miriñaque’ (in Spanish) or protuberance of the trunk at the union of the graft, whereas this did not appear in the Sweet orange rootstock (Citrus × sinensis). For the analysis, fresh samples of old leaf, young leaf, and root were collected from five different trees for each rootstock. Once processed after having been weighed, dried, and ground, they were analysed by inductively coupled plasma (ICP) analysis (Optima 3000, PerkinElmer). The result showed that the growth in aerial biomass was higher in Verna grafted on Sweet orange rootstock. The root samples of the lemon tree with Bitter orange rootstock contained a higher amount of Fe, Mn, and Zn than the samples of the lemon tree with Sweet orange rootstock. The rest of the nutrients did not show significant differences. The new and old leaves of Verna in Sweet orange rootstock showed a higher amount of Fe, Mn, and Zn than the new and old leaves of Verna in Bitter orange rootstock. Additionally, the rest of the nutrients did not show significant differences. The study revealed that this protuberance in the trunk prevents the passage of these elements from the root to the aerial part of the trunk. This is probably related to the cell-to-cell passage. Full article

Due to the high volume of peel produced, Citrus by-product processing could be a significant source of phenolic compounds, in addition to essential oil. Citrus fruit residues, which are usually dumped as waste in the environment, could be used as a source of nutraceuticals. Citrus aurantium (L), also known as sour or bitter orange, is a member of the Rutaceae family and is the result of interspecific hybridization between Citrus reticulata and Citrus maxima. The purpose of this study is to chemically and biologically evaluate the peel of C. aurantium, which is considered a solid waste destined for abandonment. To achieve more complete extraction of the phytochemicals, we used a sequential extraction process with Soxhlet using the increasing polarity of solvents (i.e., cyclohexane, chloroform, ethyl acetate, acetone, and ethanol–water mixture). Essential oil (EO) from the Citrus peel, which was present at 1.12%, was also prepared by hydrodistillation for comparison. Various phytochemical assays were used to determine the qualitative chemical composition, which was subsequently characterized using GC-MS and HPLC-DAD. The inhibitory effects of C. aurantium peel extract on two enzymes, intestinal α-glucosidase and pancreatic α-amylase, were measured in vitro to determine their potential hypoglycemic and antidiabetic actions. Each extract had a significantly different phytochemical composition. According to GC-MS analyses, which allow the identification of 19 compounds, d-limonene is the most abundant compound in both EO and cyclohexane extract, at 35.17% and 36.15% (w/w). This comparison with hydrodistillation shows the value of the sequential process in extracting this valuable terpene in large quantities while also allowing for the subsequent extraction of other bioactive substances. On the contrary, linoleic acid is abundant (54.35% (w/w)) in ethyl acetate extract (EAE) with a lower amount of d-limonene. HPLC-DAD analysis allows the identification of 11 phytochemicals, with naringenin being the most abundant flavanone, detected in acetone extract (ACE) (23.94% (w/w)), ethanol–water extract mixture (EWE) (28.71% (w/w)), and chloroform extract (CFE) (30.20% (w/w)). Several extracts significantly inhibited α-amylase and/or α-glycosidase in vitro. At a dose of 332 g/mL, ACE, CFE, and EWE inhibited the two enzymes by approximately 98%. There were strong significant correlations between naringenin and α-glucosidase inhibition and between gallic acid and α-amylase inhibition. Molecular docking experiments further verified this. Finally, oral administration of C. aurantium extracts at a dose of 2000 mg/kg did not cause any effect on mice mortality or signs of acute toxicity, indicating that it is non-toxic at these doses. These findings suggest that C. aurantium peels could be a valuable by-product by providing a rich source of non-toxic phytoconstituents, particularly those with potential antidiabetic action that needs to be confirmed in vivo. Full article

Aromatic plants have been used since antiquity as great potential sources of therapeutics in folk medicine and as preservatives in foods, because they contain many biologically active compounds. Among all, essential oils (EOs) are an important group of secondary metabolites that, even if not essential for plant survival, are significant for their allelopathic effects, either negative or positive, on microbes and the environment. From the chemical point of view, EOs are highly complex mixtures involving from several tens to hundreds of different types of volatile compounds, such as terpenoids, oxygenated terpenes, sesquiterpenes, and hydrocarbons. EOs have been widely used for their virucidal, bactericidal, fungicidal, anticancer, antioxidant, and antidiabetic activities, and the biological properties of EOs are strictly linked to their chemical composition. This study was carried out on the following commercial EOs: bergamot (Citrus bergamia), bitter orange (Citrus aurantium), clove (Eugenia caryophyllata), eucalyptus (Eucalyptus globulus), fennel (Foeniculum vulgare dulce), helichrysum (Helicrysum italicum), lavender (Lavandula officinalis), lemon (Citrus limon), oregano (Origanum vulgare), palmarosa (Cymbopogon martini), star anise (Illicium verum), tangerine (Citrus reticulate), tea tree (Melaleuca alternifolia), turmeric (Curcuma longa), Chinese yin yang (mix of Eucalyptus aetheroleum, Cymbopogon citratus, Caryophylli aetheroleum, Mentha piperita, Pinus sylvestris, Salvia rosmarinus, Lavandula officinalis, Foeniculum vulgare, Salvia officinalis, Illicium verum, Mentha arvensis, Abies siberica), Japanese yin yang (Mentha arvensis), and ylang ylang (Cananga odorata). The EOs were tested for the in vitro determination of antioxidant activity (DPPH assay) and of the sun protection factor (SPF) by means of UV-Vis spectrophotometry. These biological activities allowed us to evaluate their potential application as natural preservatives and active ingredients in foods, beverages, and cosmetics, as well as in galenic preparations. The results show that amongst the seventeen EOs studied, clove showed the highest antioxidant activity, with an EC50 of 0.36 µL/mL, followed by Chinese yin yang (5.35 µL/mL), oregano (11.58 µL/mL), and ylang ylang (12.71 µL/mL). Moreover, higher SPF values were recorded for bergamot (9.74), star anise (9.28), fennel (9.10), bitter orange (8.96), ylang ylang (8.41), and clove (8.26). Overall, clove and ylang ylang EOs resulted the best potential candidates as natural preservatives, as they showed the highest health-promoting values, because at the same time, they provided protection against oxidative stress and fought free radicals that may form after sun radiation exposure. Full article

Citrus genus is a prominent staple crop globally. Long-term breeding and much hybridization engendered a myriad of species, each characterized by a specific metabolism generating different secondary metabolites. Citrus aurantium L., commonly recognized as sour or bitter orange, can exceptionally be distinguished from other Citrus species by unique characteristics. It is a fruit with distinctive flavor, rich in nutrients and phytochemicals which possess different health benefits. This paper presents an overview of the most recent studies done on the matter. It intends to provide an in-depth understanding of the biological activities and medicinal uses of active constituents existing in C. aurantium. Every plant part is first discussed separately with regards to its content in active constituents. All extraction methods, their concepts and yields, used to recover these valuable molecules from their original plant matrix are thoroughly reported. Full article

Dried, bitter orange leaves are widely used because of their nutritious and medicinal applications. As a result, many technologies have been used to accomplish its drying process. However, drying needs a long time and high energy demand, especially in humid climates. In this paper, bitter orange leaf drying was carried out using thermal and photovoltaic solar energy (integrated system, IS), eliminating the high humidity inside of the drying chamber to improve this process. A regular solar dryer (RD) was also used to compare the kinetics, mathematical modeling, and colorimetry study (as a quality parameter), evaluating both systems’ performances. The drying leaves’ weights were stabilized after 330 min in the RD and after 240 min in the IS, with a maximum drying rate of 0.021 kg water/kg dry matter∙min, reaching a relative humidity of 7.9%. The Page and Modified Page models were the best fitting to experimental results with an Ra² value of 0.9980. In addition, the colorimetric study showed a better-preserved color using the IS, with an ∆E of 9.12, while in the RD, the ∆E was 20.66. Thus, this system implementation can reduce agroindustry costs by reducing time and energy with a better-quality and sustainable product, avoiding 53.2 kg CO₂ emissions to the environment. Full article

Dietary supplements of botanical origin are increasingly consumed due to their content of plant constituents with potential benefits on health and wellness. Among those constituents, terpenes are gaining attention because of their diverse biological activities (anti-inflammatory, antibacterial, geroprotective, and others). While most of the existing analytical methods have focused on establishing the terpenic fingerprint of some plants, typically by gas chromatography, methods capable of quantifying representative terpenes in herbal preparations and dietary supplements with combined high sensitivity and precision, simplicity, and high throughput are still necessary. In this study, we have explored the utility of capillary liquid chromatography (CapLC) with diode array detection (DAD) for the determination of different terpenes, namely limonene, linalool, farnesene, α-pinene, and myrcene. An innovative method is proposed that can be applied to quantify the targets at concentration levels as low as 0.006 mg per gram of sample with satisfactory precision, and a total analysis time <30 min per sample. The reliability of the proposed method has been tested by analyzing different dietary supplements of botanical origin, namely three green coffee extract-based products, two fat burnings containing Citrus aurantium (bitter orange), and an herbal preparation containing lime and leaves of orange trees. Full article

The aim of this study was to detect effects of bitter orange (Citrus aurantium) essential oil, commonly called neroli oil (NO) (0, 0.25, 0.50, 1, and 1.5% referred to as NO₀ NO_0.25, NO_{0. 05}, NO₁ and NO_1.5, respectively) on growth performance output and expression levels of some growth-related genes in the muscle tissue and some immune-related genes in the head kidney and pathological differences in digestive system organs of common carp Cyprinus carpio. The NO_0.25 group had a large improvement in growth efficiency at the end of the 60-day feeding cycle. Real-time PCR (Bio RAD, USA) system was used to detect variations in gene expression levels. Furthermore, NO supplementation of up to 0.25% in muscle tissue controlled the release of growth hormone (GH) and insulin-like growth factor I (IGF-I). Furthermore, in the NO_0.25 treatment category, immune response gene levels TNF-α, IL-8 and IL-1ß increased in head kidney tissue. In the histological examination of the liver and intestine, there were significant differences between fish fed with N₁ and N_1.5 diets. This study confirms that dietary supplementation of NO up to 0.25% can improve common carp growth efficiency and increase the expression of genes (GH and IGF-I) related to muscle growth, TNF-α, IL-8 and IL-1ß genes related to immune status, and liver and intestine histological status of common carp. Full article

The p-synephrine is the principal phytochemical found in bitter orange (Citrus aurantium). This substance is widely included in dietary supplements for weight loss/body fat reduction due to its potential benefits of increasing fat oxidation. For years, p-synephrine-containing dietary supplements have been marketed without proper knowledge of their true effectiveness to enhance fat utilization, especially when combined with exercise. However, the effects of p-synephrine on fat oxidation during exercise have been investigated in the last few years. The aim of the current discussion is to summarize the evidence on the effects of p-synephrine intake on fat oxidation and performance during exercise. Previous investigations have demonstrated that the acute intake of p-synephrine does not modify running sprint performance, jumping capacity, or aerobic capacity. However, the acute intake of p-synephrine, in a dose of 2–3 mg/kg of body mass, has been effective to enhance the rate of fat oxidation during incremental and continuous exercise. This effect has been observed in a range of exercise workloads between 30% and 80% of peak oxygen uptake (VO_2peak). The p-synephrine has the ability to increase the maximal rate of fat oxidation during exercise of increasing intensity without affecting the workload at which maximal fat oxidation is obtained (Fatmax). The effect of p-synephrine on fat oxidation is normally accompanied by a concomitant reduction of carbohydrate utilization during exercise, without modifying the energy expended during exercise. The shifting in substrate oxidation is obtained without any effect on heart rate during exercise and the prevalence of adverse effects is negligible. Thus, the acute use of p-synephrine, or p-synephrine-containing products, might offer some benefits for those individuals seeking higher fat utilization during exercise at low to moderate intensities. However, more research is still necessary to determine if the effect of p-synephrine on fat oxidation during exercise is maintained with chronic ingestion, in order to ascertain the utility of this substance in conjunction with exercise programs to produce an effective body fat/weight loss reduction. Full article