Antifungal Activity of Rue Essential Oil and Commercial Chitosan on Native Corn Foliar Diseases.

Native corn in Cherán, Michoacán, southwestern Mexico, represents a high-impact economic, social, and religious support, although its yield is low due to fungal diseases. Fungicides are mainly used for their control, but the fungi involved create resistance. The aims of this study are to determine the incidence of foliar diseases in the field, isolate the causal fungi, evaluate the in vitro effect of the essential oil of rue (Ruta graveolens) on them, and identify the secondary metabolites. The essential oil was obtained using the steam distillation technique on fresh plants. Also used was an industrial-grade chitosan, and the commercial fungicide benomyl was used as a positive control. Rue essential oil was characterized by mass spectrometry with ultra-high-performance liquid chromatography with electrospray ionization (UHPLC-ESI). The highest incidence of disease was obtained for leaf rust (35%), followed by gray leaf spot (GLS) (24%) and leaf blight (19%). Rue essential oil inhibited 100% of the mycelial growth of Coniothyrium phyllachorae and 96% of the mycelium of Exseroilum turcicum. The benomyl fungicide effectively inhibited C. phyllachorae (86 to 91%), but not E. turcicum, with the opposite effect when using chitosan by inhibiting 89 to 90% of the latter's mycelial development. The majority compound of the essential oil of R. graveolens was 2-(3-phenylprop-2-enoyl)chromen-4-one; however, fatty acids were also detected: linoleic, palmitic, and retinoic acid.

Ruta graveolens: Boost Melanogenic Effects and Protection against Oxidative Damage in Melanocytes.

Vitiligo, an acquired depigmentation disorder, is characterized by the loss of functional melanocytes and epidermal melanin. In recent years, research has focused on promoting melanin biosynthesis and protecting melanocytes to reduce stress-related damage for the purpose of applying it to vitiligo treatment. Ruta graveolens L. has been utilized as a medicinal herb in diverse traditional medicine systems to address conditions like vitiligo. In this investigation, we isolated and purified 16 unique alkaloid compounds from the chloroform extracts of R. graveolens, encompassing a new quinoline alkaloid and several recognized compounds. Bioactivity analysis showed that compound 13, an alkaloid derived from R. graveolens, promotes melanin production while protecting PIG3V melanocytes against 4-tert-butylphenol (4-TBP)-induced oxidative damage by downregulating endoplasmic reticulum (ER) stress and pro-inflammatory cytokines through interleukin-6 (IL-6) regulation. Additionally, the compound suppressed the expression of Bip, IRE1, p-IRE1, and XBP-1 proteins, suggesting a potential antioxidant function. These findings suggest that compound 13 isolated from R. graveolens can augment melanogenesis in melanocytes, reduce endoplasmic reticulum (ER) stress, and ameliorate vitiligo exacerbation. The melanogenic activity observed in the chloroform fraction emphasizes R. graveolens's potential as a novel therapeutic target for vitiligo treatment, warranting further exploration in future studies.

(+)-/(-)-Rutabenzofuran A and (+)-/(-)- Rutabenzofuran B: Two unprecedented pairs of Z/E isomeric benzofuran enantiomers from the aerial part of Ruta graveolens L.

Two pairs of Z/E isomeric benzofuran enantiomers possessing unprecedented carbon skeletons featuring ring cleavage and addition reactions in the α-pyrone ring of furocoumarin, named rutabenzofuran A [(+)-1 and (-)-1], and rutabenzofuran B [(+)-2 and (-)-2], respectively, were isolated as minor compounds from the water extract of the aerial part of Ruta graveolens L. Their structures were determined by extensive spectroscopic data analysis. The absolute configurations were assigned by comparing the optical rotation with previous research and the experimental circular dichroism (CD) spectra with the calculated electronic CD (ECD) spectra. (-)-1, (+)-2, and (-)-2 were evaluated for antibacterial, anticoagulant, anticancer, and acetylcholinesterase (AChE) inhibitory activities. No anticancer or anticoagulant activities were observed, yet (-)-2 exhibited weak antibacterial activity against Salmonella enterica subsp. Enterica. At the same time, (-)-1, (+)-2, and (-)-2 displayed weak inhibitory activity on AChE.

Spectrum-effect relationship between UPLC fingerprints and melanogenic effect of Ruta graveolens L.

A total of 29 batches of R. graveolens were used in this study, their fingerprints were obtained by ultra-performance liquid chromatography (UPLC) and their melanogenesis activities were evaluated. The common peaks were identified by quadrupole-orbitrap high-resolution mass spectrometry (Q-Orbitrap-HRMS). Eleven coumarins, six alkaloids, three flavonoids, three phenolic acids, and four other compounds were found. The spectrum-effect relationships between R. graveolens' chemical fingerprints, the melanin synthesis, and tyrosine's activation activities were established through chemometrics methods which in detail principal component analysis (PCA), gray correlation analysis (GRA), bivariate correlation analysis (BCA) and orthogonal partial least squares analysis (OPLS). The results showed that P18 (bergapten), P22 (isoimperatorin), P15 (kokusaginine), P7 (rutin), P12 (psoralen), and P13 (graveolinine) were relevant to intracellular melanin synthesis activity and tyrosinase activity. Among them, P18 (bergapten), P15 (kokusaginine), and P12 (psoralen) were validated with good melanogenesis activities. This study provides a research basis for future quality control and medicinal application of R. graveolens.

The Influence of Exogenous Phenylalanine on the Accumulation of Secondary Metabolites in Agitated Shoot Cultures of Ruta graveolens L.

This study aimed to examine the influence of the addition of a precursor (phenylalanine) on the accumulation of secondary metabolites in agitated shoot cultures of Ruta graveolens. Cultures were grown on Linsmaier and Skoog (LS) medium, with plant growth regulators (0.1 mg/L α-naphthaleneacetic acid-NAA-and 0.1 mg/L 6-benzylaminopurine-BAP). Phenylalanine was added to the cultures at a concentration of 1.25 g/L after 4 and 5 weeks of growth cycles. Biomass was collected after 2, 4, and 7 days of precursor addition. Both control and experimental cultures had the same secondary metabolites accumulated. Using the HPLC method, linear furanocoumarins (bergapten, isoimperatorin, isopimpinellin, psoralen, and xanthotoxin), furoquinoline alkaloids (γ-fagarine, 7-isopentenyloxy-γ-fagarine, and skimmianine), and catechin were detected and quantified in the methanolic extracts. In turn, phenolic acids, such as gallic acid, protocatechuic acid, p-hydroxybenzoic acid, syringic acid, p-coumaric acid, and ferulic acid were detected in hydrolysates. The production of phenolic acids and catechin (1.5-fold) was significantly increased by the addition of precursor, while there was no significant effect on the production of coumarins and alkaloids. The highest total content of phenolic acids (109 mg/100 g DW) was obtained on the second day of phenylalanine addition (the fourth week of growth cycles). The dominant phenolic compounds were p-coumaric acid (maximum content 64.3 mg/100 g DW) and ferulic acid (maximum content 35.6 mg/100 g DW). In the case of catechins, the highest total content (66 mg/100 g DW) was obtained on the third day of precursor addition (the fourth week of growth cycles). This study is the first to document the effect of feeding the culture medium with phenylalanine on the accumulation of bioactive metabolites in in vitro cultures of R. graveolens.

Antifungal, Repellency, and Insecticidal Activities of Cymbopogon distans and Ruta graveolens Essential Oils and Their Main Chemical Constituents.

Essential oils produced by Cymbopogon distans and Ruta graveolens with a similar Chinese name could be explained as book fragrance in the Chinese idiom 'shu xiang men di', namely, a wealthy intellectual family according to ancient Chinese. Therefore, volatile oils from these two plants and their main compounds were tested to explore their antifungal, repellent, and insecticide actions. In this study, the essential olis (EO) of C. distans exhibited significant antifungal activity against Rhizopus stolonifera (97 %), Mucor racemosus (97 %), and Trichoderma viride (84 %); its main compounds exhibit interesting activity, such as methyleugenol (87 %) and elemicine (85 %) against T. viride and butyl hydroxytoluene against M. racemosus (90 %) and R. stolonifera (95 %). The EO of R. graveolens and other major chemical constituents showed weak inhibitory effects against other fungi (Aspergillus flavus and Fusarium oxysporum). Then, EO (C. distans and R. graveolens) and its main compounds exhibited obvious repellent activity (more than 85 %) at a concentration of 16 nL/cm2 , which was consistent with the repellency of the positive control (DEET). In terms of insecticidal activity, the mortality of C. distans volatile oil against R. padi (56.4 %) was lower than that of R. graveolens volatile oil (92.4 %), and all compounds showed weak lethal effects. These results provide a natural substance for controlling fungi and insects when storing books and that can be used as a biological pesticide for industrial production. Through our study, the book fragrance in the Chinese idiom 'shu xiang men di' was speculated to be the EO odor of C. distans.

Phenolic Content and in Vitro Antioxidant, Anti-Inflammatory and antimicrobial Evaluation of Algerian Ruta graveolens L.

Plants constitute a valuable source of natural antioxidants such as polyphenols and are responsible for exhibiting many biologically significant functions. Ruta species including Ruta chalepensis L. and Ruta graveolens L. are widespread species in Algeria and are used as medicinal plants to treat various diseases; however, so far, most of the conducted studies focused on analyzing alkaloids and essential oils mostly on R. chalepensis. The aim of the present research is to investigate the phenolic profile of the aerial parts of Ruta graveolens L. from Algeria and assess its in vitro antioxidant, anti-inflammatory and antimicrobial properties. The total polyphenols and flavonoids were assessed using colorimetric methods, and the individual polyphenols were identified and quantified using HPLC-DAD-ESI-MS. The antioxidant activity was evaluated with DPPH and ß-carotene tests, and the anti-inflammatory activity with inhibition of bovine serum albumin denaturation and HRBC membrane stabilization methods. The results showed that Ruta graveolens extract is rich in phenolic compounds with a total phenol and flavonoid contents of 41.63±0.394 mg GAE/gE and 13.97±0.33 mg EQ/gE, respectively. Nine phenolic compounds were determined, including three phenolic acids and six flavonoids. Rutin was the major phenolic compound in Ruta graveolens (464.95 µg/g), followed by syringic acid (179.74 µg/g), and naringenin (109.78 µg/g). R. graveolens phenolic extract also showed good antioxidant activity with values of 0.77 mM TE/g DW and 0.37 mM ß-CE/g DW with DPPH and ß-carotene tests, respectively. For the anti-inflammatory activity, the highest tested concentration (200 µg/mL) gave 50.61 % of inhibition of the denaturation of albumin and 44.12 % of membrane stabilization. With regards to antimicrobial results, Staphylococcus aureus was the most sensitive bacteria with an inhibition zone of 14.37 mm and MIC value of 0.625 mg/mL, followed by Listeria monocytogenes (11.75 mm and MIC=1.25 mg/mL), and Escherichia coli (10.25 mm and MIC=1.25 mg/mL).

A Candidate for Health Promotion, Disease Prevention and Treatment, Common Rue (Ruta graveolens L.), an Important Medicinal plant in Traditional Medicine.

BACKGROUND: Ruta graveolens L. belongs to Rutaceae; it is a semi-wood perennial or a small evergreen sub-shrub, which is native to Southern Europe, West of Asia and Northern Africa. OBJECTIVE: The goal of this manuscript was to outline the most notable traditional and modern advantages and pharmaceutical benefits of common rue. METHODS: The manuscript covers review articles, randomized control experiments, analytical studies and observations, which have been gathered from different sources such as Google Scholar, Scopus, Science Direct and PubMed. A review of the literature was carried out using the keywords rutin, Ruta graveolens L., rue, common rune, coumarin, natural products and pharmaceutical benefits. RESULTS: Rue contains quinoline alkaloids, such as graveoline and graveolinine, acridone alkaloids, such as furacridone and gravacridone, the furanoquinoline dictamnine, coumaris, such as gravelliferone, isorutarin, rutacultin, rutaretin, and suberenone, and the furanocoumarins 5-methoxypsoralen (bergapten) and 8-methoxypsoralen (xanthotoxine). Most of its aromatic and medicinal properties are from its rutin, and essential oil. It has been used in folk medicines as a stimulant, anti-inflammatory and analgesic properties, anti-androgenic activity, anti-hyperglycemic effects, anti-hyperlipidemic effects, xanthine oxidase inhibition activity, anticancer properties. CONCLUSION: According to pharmacological and phytochemical advantages, pennyroyal shows its importance as a medicinal plant in both modern medicinal science and traditional medicine.

Phytochemical Characterization, and Antioxidant and Antimicrobial Properties of Agitated Cultures of Three Rue Species: Ruta chalepensis, Ruta corsica, and Ruta graveolens.

The in vitro cultures of the following three species of the genus Ruta were investigated: R. chalepensis, R. corsica, and R. graveolens. The dynamics of biomass growth and accumulation of secondary metabolites in the 3-, 4-, 5-, 6-, and 7-week growth cycle were analysed. The antioxidant capacity of the methanol extracts obtained from the biomass of the in vitro cultures was also assessed by different in vitro assays: 1,1-diphenyl-2-picrylhydrazil (DPPH), reducing power, and Fe2+ chelating activity assays. Moreover, a preliminary screening of the antimicrobial potential of the extracts was performed. The extracts were phytochemically characterized by high-performance liquid chromatography (HPLC), which highlighted the presence of linear furanocoumarins (bergapten, isoimperatorin, isopimpinellin, psoralen, and xanthotoxin) and furoquinoline alkaloids (γ-fagarine, 7-isopentenyloxy-γ-fagarine, and skimmianine). The dominant group of compounds in all the cultures was coumarins (maximum content 1031.5 mg/100 g DW (dry weight), R. chalepensis, 5-week growth cycle). The results of the antioxidant tests showed that the extracts of the three species had varied antioxidant capacity: in particular, the R. chalepensis extract exhibited the best radical scavenging activity (IC50 = 1.665 ± 0.009 mg/mL), while the R. graveolens extract displayed the highest chelating property (IC50 = 0.671 ± 0.013 mg/mL). Finally, all the extracts showed good activity against Staphylococcus aureus with MIC values of 250 µg/mL for the R. corsica extract and 500 µg/mL for both R. graveolens and R. chalepensis extracts.

Ruta graveolens, Peganum harmala, and Citrullus colocynthis methanolic extracts have in vitro protoscolocidal effects and act against bacteria isolated from echinococcal hydatid cyst fluid.

Echinococcosis is a common and endemic disease that affects both humans and animals. In this study, the in vitro activities of methanolic extracts of Ruta graveolens, Peganum harmala aerial parts, and Citrullus colocynthis seeds against protoscolosis and isolated bacterial strains from hydatid cysts were assessed using disc diffusion methods and Minimum Inhibitory Concentration (MIC). The chemical composition of three methanolic extracts was studied using LC-MS. After 3 h of exposure to 40 mg/mL R. graveolens extract, a tenfold protoscolocidal effect was seen when compared to the convintional medication (ABZ) for the same duration (P < 0.05). The bacteria listed below were isolated from hydatid cyst fluid collected from a variety of sick locations, including the lung and liver. Micrococcus spp., E. coli, Klebsiella oxytoca, Enterobacter aerogenes, Enterobacter amnigenus, Pseudomonas aeruginosa, Staphylococcus xylosus, and Achromobacter xylosoxidans are among the bacteria that have been identified. The most effective extract was R. graveolens, followed by P. harmala and C. colocynthis, according to the results of antibacterial activity using the disc diffusion method. R. graveolens extract had the lowest MIC values (less than 2 mg/mL) against all microorganisms tested. This shows that the R. graveolens extract has additional properties, such as the ability to be both scolocidal and bactericidal. Because these bacteria are among the most prevalent pathogenic bacteria that increase the risk of secondary infection during hydatid cysts, the results of inhibitory zones and MICs of the R. graveolens methanol extract are considered highly promising.

Chemical constituents of Ruta graveolens L. and their melanogenic effects and action mechanism.

Ruta graveolens L. has been widely used to treat various skin ailments, especially vitiligo. In this study, we isolated a new furanocoumarin named Rutagrarin (1) along with 14 known compounds (2-15) from the aerial parts of R. graveolens and elucidated their chemical structures via various spectroscopy. We found that compound 5 promoted melanogenesis and tyrosinase activity in B16 cells. Further investigation on underlying mechanisms revealed that compound 5 activated the transcription of microtia-related transcription factors and promoted the production of melanin in B16 cells via the Akt/GSK-3ß/ß-catenin pathway. Therefore, we confirmed the traditional efficacy of R. graveolens and speculated that compound 5 could be used as a natural drug to treat vitiligo.

Ruta Essential Oils: Composition and Bioactivities.

Ruta L. is a typical genus of the citrus family, Rutaceae Juss. and comprises ca. 40 different species, mainly distributed in the Mediterranean region. Ruta species have long been used in traditional medicines as an abortifacient and emmenagogue and for the treatment of lung diseases and microbial infections. The genus Ruta is rich in essential oils, which predominantly contain aliphatic ketones, e.g., 2-undecanone and 2-nonanone, but lack any significant amounts of terpenes. Three Ruta species, Ruta chalepensis L., Ruta graveolens L., and Ruta montana L., have been extensively studied for the composition of their essential oils and several bioactivities, revealing their potential medicinal and agrochemical applications. This review provides a systematic evaluation and critical appraisal of publications available in the literature on the composition and bioactivities of the essential oils obtained from Ruta species and includes a brief outlook of the potential applications of nanotechnology and chitosan-based products of Ruta essential oils.

Colombian Essential Oil of Ruta graveolens against Nosocomial Antifungal Resistant Candida Strains.

Drug resistance in antifungal therapy, a problem unknown until a few years ago, is increasingly assuming importance especially in immunosuppressed patients and patients receiving chemotherapy and radiotherapy. In the past years, the use of essential oils as an approach to improve the effectiveness of antifungal agents and to reduce antifungal resistance levels has been proposed. Our research aimed to evaluate the antifungal activity of Colombian rue, Ruta graveolens, essential oil (REO) against clinical strains of Candida albicans, Candida parapsilopsis, Candida glabrata, and Candida tropicalis. Data obtained showed that C. tropicalis and C. albicans were the most sensitive strains showing minimum inhibitory concentrations (MIC) of 4.1 and 8.2 µg/mL of REO. Time-kill kinetics assay demonstrated that REO showed a fungicidal effect against C. tropicalis and a fungistatic effect against C. albicans. In addition, an amount of 40% of the biofilm formed by C. albicans was eradicated using 8.2 µg/mL of REO after 1 h of exposure. The synergistic effect of REO together with some antifungal compounds was also investigated. Fractional inhibitory concentration index (FICI) showed synergic effects of REO combined with amphotericin B. REO Lead a disruption in the cellular membrane integrity, consequently resulting in increased intracellular leakage of the macromolecules, thus confirming that the plasma membrane is a target of the mode of action of REO against C. albicans and C. tropicalis.

Packham's Triumph Pears (Pyrus communis L.) Post-Harvest Treatment during Cold Storage Based on Chitosan and Rue Essential Oil.

Pears (Pyrus communis L.) cv. Packham's Triumph are very traditional for human consumption, but pear is a highly perishable climacteric fruit with a short shelf-life affected by several diseases with a microbial origin. In this study, a protective effect on the quality properties of pears was evidenced after the surface application of chitosan-Ruta graveolens essential oil coatings (CS + RGEO) in four different concentrations (0, 0.5, 1.0 and 1.5 %, v/v) during 21 days of storage under 18 °C. After 21 days of treatment, a weight loss reduction of 10% (from 40.2 ± 5.3 to 20.3 ± 3.9) compared to the uncoated pears was evident with CS + RGEO 0.5%. All the fruits' physical-chemical properties evidenced a protective effect of the coatings. The maturity index increased for all the treatments. However, the pears with CS + RGEO 1.5% were lower (70.21) than the uncoated fruits (98.96). The loss of firmness for the uncoated samples was higher compared to the coated samples. The pears' most excellent mechanical resistance was obtained with CS + RGEO 0.5% after 21 days of storage, both for compression resistance (7.42 kPa) and force (22.7 N). Microbiological studies demonstrated the protective power of the coatings. Aerobic mesophilic bacteria and molds were significantly reduced (in 3 Log CFU/g compared to control) using 15 µL/mL of RGEO, without affecting consumer perception. The results presented in this study showed that CS + RGEO coatings are promising in the post-harvest treatment of pears.

Separation and qualitative study of Ruta graveolens L. essential oil components by prep-GC, GC-QTOF-MS and NMR.

In order to solve the problem of inaccuracy of using GC-QTOF-MS combined with NIST14 database in analyzing Ruta graveolens L. essential oil components, systematic isolation and characterization of chemicals from essential oil were carried on. Seventeen compounds which were 3 terpenoids, 8 lipid compounds, 3 alcohol compounds and 3 ketones were separated by preparative GC after dividing the essential oil into 5 groups of fractions by silica gel column. The chemical structures of isolated compounds were identified by GC-QTOF-MS and NMR. Three new in general compounds (50, 53 and 55) were isolated. And proton and carbon spectra of six compounds were provided for the first time. Through separation and structure identification of the compounds, qualitative analysis of total chemical components of the essential oil was increased from 42.0% to 90.3%. This research would be of great significance to application of Ruta graveolens L. essential oil.

Cytotoxic Plant Extracts towards Insect Cells: Bioactivity and Nanoencapsulation Studies for Application as Biopesticides.

The potential of plant extracts as bioinsecticides has been described as a promising field of agricultural development. In this work, the extracts of Punica granatum (pomegranate), Phytolacca americana (American pokeweed), Glandora prostrata (shrubby gromwell), Ulex europaeus (gorce), Tagetes patula (French marigold), Camellia japonica red (camellia), Ruta graveolens (rue or herb-of-grace) were obtained, purified, and their activity against Spodoptera frugiperda (Sf9) insect cells was investigated. From the pool of over twenty extracts obtained, comprising different polarities and vegetable materials, less polar samples were shown to be more toxic towards the insect cell line Sf9. Among these, a dichloromethane extract of R. graveolens was capable of causing a loss of viability of over 50%, exceeding the effect of the commercial insecticide chlorpyrifos. This extract elicited chromatin condensation and the fragmentation in treated cells. Nanoencapsulation assays of the cytotoxic plant extracts in soybean liposomes and chitosan nanostructures were carried out. The nanosystems exhibited sizes lower or around 200 nm, low polydispersity, and generally high encapsulation efficiencies. Release assays showed that chitosan nanoemulsions provide a fast and total extract release, while liposome-based systems are suitable for a more delayed release. These results represent a proof-of-concept for the future development of bioinsecticide nanoformulations based on the cytotoxic plant extracts.

Reduction of Postharvest Quality Loss and Microbiological Decay of Tomato "Chonto" (Solanum lycopersicum L.) Using Chitosan-E Essential Oil-Based Edible Coatings under Low-Temperature Storage.

The tomato (Solanum lycopersicum L.) is one of the many essential vegetables around the world due to its nutritive content and attractive flavor. However, its short shelf-life and postharvest losses affect its marketing. In this study, the effects of chitosan-Ruta graveolens (CS + RGEO) essential oil coatings on the postharvest quality of Tomato var. "chonto" stored at low temperature (4 °C) for 12 days are reported. The film-forming dispersions (FFD) were eco-friendly synthesized and presented low viscosities (between 0.126 and 0.029 Pa s), small particle sizes (between 1.29 and 1.56 µm), and low densities. The mature index (12.65% for uncoated fruits and 10.21% for F4 coated tomatoes), weight loss (29.8% for F1 and 16.7% for F5 coated tomatoes), and decay index (3.0 for uncoated and 1.0 for F5 coated tomatoes) were significantly different, indicating a preservative effect on the quality of the tomato. Moreover, aerobic mesophilic bacteria were significantly reduced (in five Log CFU/g compared to control) by using 15 µL/mL of RGEO. The coatings, including 10 and 15 µL/mL of RGEO, completely inhibited the mold and yeast growth on tomato surfaces without negatively affecting the consumer acceptation, as the sensorial analysis demonstrated. The results presented in this study show that CS + RGEO coatings are promising in the postharvest treatment of tomato var. "chonto".

Ruta graveolens as a potential source of neuroactive compounds to promote and restore neural functions.

Nutraceuticals had always been known for their therapeutic effects in ancient medicine and had been the primary healing remedy until the introduction of modern chemistry and pharmacology. However, their use has not been dismissed but actually is acquiring a new acclamation among the scientific community especially for their efficacy on the Central Nervous System (CNS). Molecular mechanisms of the most common neurodegenerative diseases are now being uncovered and along with that the molecules that drive the neurodegenerative processes. It is not surprising that some natural compounds can interact with those molecules and interfere with the pathological pathways halting the cascades that ultimately lead to neuronal cell death. The plant Ruta graveolens has gained increased attention in medicinal chemistry due to its beneficial role to treat a variety of human diseases and also because of the presence of a huge number of compounds belonging to different classes of natural products, including neuroactive compounds potentially able to promote neuroprotection. Among all the components of the plant extract, rutin - which is highly, if not the most, abundant - positively interacts with the neurophysiology of the CNS too, being particularly efficient against neurotoxicity. Rutin, has proven to be protective in a variety of experimental settings of neurodegeneration. Finally, it has been shown that the water extract of Ruta graveolens (RGWE) induces death of glioblastoma cells but not of neuronal cells. Moreover, it also fosters cell cycle re-entry and differentiation of neuronal cells. This peculiarity represents a promising tool to promote neural plasticity in pathological conditions.

Synthesis, Characterization, and Histological Evaluation of Chitosan-Ruta Graveolens Essential Oil Films.

The development of new biocompatible materials for application in the replacement of deteriorated tissues (due to accidents and diseases) has gained a lot of attention due to the high demand around the world. Tissue engineering offers multiple options from biocompatible materials with easy resorption. Chitosan (CS) is a biopolymer derived from chitin, the second most abundant polysaccharide in nature, which has been highly used for cell regeneration applications. In this work, CS films and Ruta graveolens essential oil (RGEO) were incorporated to obtain porous and resorbable materials, which did not generate allergic reactions. An oil-free formulation (F1: CS) and three different formulations containing R. graveolens essential oil were prepared (F2: CS-RGEO 0.5%; F3: CS+RGEO 1.0%; and F4: CS+RGEO 1.5%) to evaluate the effect of the RGEO incorporation in the mechanical and thermal stability of the films. Infrared spectroscopy (FTIR) analyses demonstrated the presence of RGEO. In contrast, X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis showed that the crystalline structure and percentage of CS were slightly affected by the RGEO incorporation. Interesting saturation phenomena were observed for mechanical and water permeability tests when RGEO was incorporated at higher than 0.5% (v/v). The results of subdermal implantation after 30 days in Wistar rats showed that increasing the amount of RGEO resulted in greater resorption of the material, but also more significant inflammation of the tissue surrounding the materials. On the other hand, the thermal analysis showed that the RGEO incorporation almost did not affect thermal degradation. However, mechanical properties demonstrated an understandable loss of tensile strength and Young's modulus for F3 and F4. However, given the volatility of the RGEO, it was possible to generate a slightly porous structure, as can be seen in the microstructure analysis of the surface and the cross-section of the films. The cytotoxicity analysis of the CS+RGEO compositions by the hemolysis technique agreed with in vivo results of the low toxicity observed. All these results demonstrate that films including crude essential oil have great application potential in the biomedical field.

Colletotrichum Gloesporioides Inhibition In Situ by Chitosan-Ruta graveolens Essential Oil Coatings: Effect on Microbiological, Physicochemical, and Organoleptic Properties of Guava (Psidium guajava L.) during Room Temperature Storage.

Guava is a fruit appreciated worldwide for its high content of bioactive compounds. However, it is considered a highly perishable fruit, generally attacked by pathogenic species such as the fungi Colletotrichum gloeosporioides, which causes anthracnosis. To diminish the losses caused by pathogenic fungi, coatings of chitosan (CS) with Ruta graveolens essential oil (RGEO) in different concentrations (0.5, 1.0, 1.5% v/v) were applied in situ and their effects on the physical properties and microbiological quality of the guavas were studied. The CS+RGEO coated fruits exhibited better physicochemical behavior and lower microbiological decay as compared to the uncoated guavas, demonstrating the effectiveness of the coatings, especially those with 1.5% of RGEO content. All the fruits coated had greater acceptance and quality than the controls, being more those with essential oil incorporation. In situ investigation of C. gloesporioides infection of guavas demonstrated that the CS+RGEO coated guavas showed a high percentage of inhibition in the development of anthracnose lesions. In the present investigation, an alternative method has been proposed to extend the stability of the guavas fruit up to 12 days with application in the food industry.