Volume 75, Issue 11-12

This study aimed to evaluate the antibacterial and antibiotic-enhancing effects of the essential oil obtained from Ocimum gratissimum L. (OEOg) alone or in association with light-emitting diodes (LED) lights. The essential oil was obtained by hydrodistillation and its chemical composition analysed by gas chromatography coupled to mass spectrometry. The antibacterial and antibiotic-enhancing activities against multiresistant strains of Staphylococcus aureus and Escherichia coli were evaluated by the gaseous contact method. The analysis of the photoinductive effect on the antibacterial activity of the OEOg and antibiotics was assessed through exposure to different LED lights (red, blue and yellow). The phytochemical analysis identified five compounds, including eugenol, as the major constituent. The OEOg caused a significant inhibition of the halo, indicating a direct antibacterial effect. Exposure to the LED lights significantly enhanced the activity of the OEOg against E. coli . On the other hand, the action of the essential oil against S. aureus was enhanced by exposure to both blue and yellow lights. The effects of LED light exposure on the activity of conventional antibiotics varied significantly according to the drug and the bacterial strain. However, most combinations of LED lights and the OEOg presented synergistic effects against resistant bacterial strains, indicating enhanced antibacterial activity. Thus, these in vitro findings suggest that both OEOg and LED lights have promising antibacterial effects. Nevertheless, further research is required to evaluate in vivo the potential of these therapies for the treatment of infectious skin diseases.

The coronavirus is currently extremely contagious for humankind, which is a zoonotic tropical disease. The pandemic is the largest in history, affecting almost the whole world. What makes the condition the worst of all is no specific effective treatment available. In this article, we present an extended and modified form of SIR and SEIR model, respectively. We begin by investigating a simple mathematical model that describes the pandemic. Then we apply different safety measures to control the pandemic situation. The mathematical model with and without control is solved by using homotopy perturbation method. Obtained solutions have been presented graphically. Finally, we develop another mathematical model, including quarantine and hospitalization.

Metallo-aminopeptidases (mAPs) control many physiological processes. They are classified in different families according to structural similarities. Neutral mAPs catalyze the cleavage of neutral amino acids from the N-terminus of proteins or peptide substrates; they need one or two metallic cofactors in their active site. Information about marine invertebrate’s neutral mAPs properties is scarce; available data are mainly derived from genomics and cDNA studies. The goal of this work was to characterize the biochemical properties of the neutral APs activities in eight Cuban marine invertebrate species from the Phyla Mollusca, Porifera, Echinodermata, and Cnidaria. Determination of substrate specificity, optimal pH and effects of inhibitors (1,10-phenanthroline, amastatin, and bestatin) and cobalt on activity led to the identification of distinct neutral AP-like activities, whose biochemical behaviors were similar to those of the M1 and M17 families of mAPs. Additionally, M18-like glutamyl AP activities were detected. Thus, marine invertebrates express biochemical activities likely belonging to various families of metallo-aminopeptidases.

Hexanal is a 6-carbon aldehyde that smells like green leaves and urine to mammals. However, its physiological effects remain unclear. In particular, the effects of hexanal inhalation on the central nervous system have not been clarified. We investigated hexanal inhalation in mice and conducted a series of behavioral experiments to examine the neuropsychological effects of hexanal. After inhaling hexanal emissions for 30 min, mice were subjected to an open field test, a hot plate test, a grip strength test, an elevated plus maze test, a Y-maze test, a tail suspension test, and a forced swim test to examine the effects of hexanal odor on mouse behavior. Compared to controls, mice that inhaled hexanal exhibited reduced anxiety-like behavior in the elevated plus maze test. In addition, mice that inhaled hexanal displayed significantly improved spatial cognitive ability in the Y-maze test. However, in some behavioral experiments there was no significant difference between control mice and mice that inhaled hexanal. The results of this study suggest that hexanal inhalation causes anxiolytic effects and improves cognitive function in mice. These findings may have implications for safety management procedures and determining the effective use of household goods containing hexanal, though further work is required.

Drought stress has a significant effect on the growth, physiology and biochemistry of medicinal plants. SDIR1 ( Salt- and Drought-Induced Ring Finger1 ), a C 3 H 2 C 3 -type RING-finger E3 ubiquitin ligase gene plays an important role in the stress response of various plants. However, the role of this gene is not clear in Coptis chinensis . In this study, the CcSDIR1 gene was cloned from C. chinensis using RACE and RT-PCR. Sequence analysis revealed that CcSDIR1 had an open reading frame of 840 bp that encodes 279 amino acids with a theoretical molecular weight about 31 kDa and pI value of 5.65 and shared conserved domains with other plants. On comparison with the wild-type plants, overexpression of CcSDIR1 in transgenic tobaccos increased drought tolerance and showed better growth performance. However, lower malondialdehyde contents and high antioxidant enzyme activities were observed in transgenic tobacco plants compared to wild-type plants. In addition, Evans blue staining showed high cell viability of transgenic lines under drought stress. These results suggest that CcSDIR1 regulates various responses to drought stress by increasing antioxidant enzyme activities and reducing oxidative damage. From the study results, the CcSDIR1 gene will be very useful for drought stress research in plants.

Sepsis-induced lung injury was the most common cause of death in patients. Topiroxostat, a novel xanthine oxidoreductase inhibitors, possessed obvious organ protectives effects. Xanthine oxidase played a vital role in acute lung injury. The study aimed to investigate the roles of Topiroxostat in sepsis-induced lung injury. The sepsis rats were established using cecum ligation and perforation. The lung damage induced by sepsis was evaluated by Hematoxylin and Eosin staining and lung tissue wet to dry ratio. The oxidative stress was detected by measurement of reactive oxygen species, malondialdehyde, myeloperoxidase and superoxide dismutase (SOD). The pro-inflammatory mediators, tumor necrosis factor-α, interleukin (IL)-1β, IL-6 and monocyte chemotactic protein 1, were measured by Enzyme-Linked Immunosorbent Assay. The cell apoptosis in lung was detected by TUNNEL staining and western blot analysis of apoptosis-related proteins including pro-apoptosis proteins, Bax, cleaved caspase9, cleaved caspase3 and anti-apoptosis protein Bcl2. The results showed that Topiroxostat significantly reduced lung damage, along with decreased oxidative stress, inflammation response and apoptosis in sepsis rats. Topiroxostat exerted markedly protective effects in sepsis-induced lung injury and could be an antioxidant in treating sepsis-induced lung injury.

The interactions between six anthocyans (cyanidin-3- O -glucoside, delphinidin-3- O -glucoside, malvidin-3- O -glucoside, cyanidin-3- O -rutinoside, delphinidin-3- O -rutinoside, malvidin-3- O -rutinoside) and cyclodextrins were investigated by means of computational techniques. Four different structures of the aforementioned anthocyans were considered, as a result of the dependence structure – pH value (flavylium cations in acidic medium, hemiketals in neutral solutions and two tautomeric quinones in alkaline environment). The results outlined that the anthocyanidin-3- O -rutinoside are favored for the obtaining of inclusion complexes with the cyclodextrins, mostly due to the larger number of OH groups involved in the formation of hydrogen bonds. For all the four types of structures, best results have been obtained for β- and γ-cyclodextrins.

Although chemical interactions play an essential role in lizard social behavior, the chemical composition of the femoral gland secretions that many lizards use for communication is known for only a few species, mainly European Lacertids. The tegu lizard, Salvator merianae , is the only species of the Teiidae family for which there is available information on lipids in femoral secretions, but only for captive bred males from Argentina. Here, based on mass spectra obtained by GC-MS, we found 69 lipophilic compounds in femoral gland secretions of wild males S. merianae from Brazil, including cholesterol and high amounts of saturated fatty acids (mainly hexadecanoic and octadecanoic). We found contrasting differences between wild and captive-bred males, which lack cholesterol but present high amount of 9,12-octadecadienoic acid. These within-species differences between wild and captive lizards strongly suggest the important influence of different diets on the chemical composition of the femoral gland secretion and suggest caution when interpreting results from captive animals, even in the same species.

Nectaroscordum siculum ssp. bulgaricum (Janka) Stearn ( Allium siculum subsp. dioscoridis (Sm.) K. Richt.) is a traditional culinary spice from South-East Europe. Studies of N. siculum have focused mainly on the botanical and taxonomic characteristics of this species and there is no data available in the scientific literature about its metabolite profile. Thus, the aim of the current study was metabolite profiling of four wild populations of N. siculum grown in Bulgaria by gas chromatography coupled to mass spectrometry (GC-MS) and subsequent principal component analysis (PCA) of the data obtained. The identified primary metabolites (carbohydrates, amino acids, organic acids and lipids) are initial compounds for the biosynthesis of different plant secondary metabolites, such as polyphenols and flavour compounds with valuable biological activities for humans. The health benefits of the phenolic acids identified in this study have been a prerequisite for the implementation of N. siculum in different food systems in order to increase their quality and biological value.

The aim of this study was to investigate the effects of extracts and pure Artemisia dracunculus L. (tarragon) metabolites on the antimonoamine oxidase and anticholinesterase activities. The compounds were characterized as stigmasterol (1) , herniarin (2) , (2E,4E)- 1-(piperidin-1-yl)undeca-2,4-diene-8,10-diyn-1-one (3) , (2E,4E)- N-isobutylundeca-2,4-dien-8,10-diynamide (4), 3,4-dehydroherniarin (5) and skimmin (6) by 1 H-NMR, 13 C-NMR, 1D and 2D NMR methods. The compounds 5 and 6 were isolated from tarragon for the first time. The extracts and pure compounds have inhibitory effects on the human monoamine oxidase ( h MAO) A and B enzymes, whereas they did not exhibit any anticholinesterase activities. Among the tarragon compounds, only 2 and 6 compounds showed the inhibitory effects against h MAO A (IC 50  = 51.76 and 73.47 μM, respectively) and h MAO B (IC 50  = 0.84 and 1.63 mM, respectively). In the study, herniarin content in the extracts was also analysed by high-performance liquid chromatography and it was found that there was a relationship between the inhibition effects of the extracts and their herniarin content.

Chemical composition and anticholinesterase activity of the essential oil of Pavetta graciliflora Wall. ex Ridl. (Rubiaceae) was examined for the first time. The essential oil was obtained by hydrodistillation and was fully characterized by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS). A total of 20 components were identified in the essential oil, which made up 92.85% of the total oil. The essential oil is composed mainly of β-caryophyllene (42.52%), caryophyllene oxide (25.33%), β-pinene (8.67%), and α-pinene (6.52%). The essential oil showed weak inhibitory activity against acetylcholinesterase (AChE) (I%: 62.5%) and butyrylcholinesterase (BChE) (I%: 65.4%) assays. Our findings were shown to be very useful for the characterization, pharmaceutical, and therapeutic applications of the essential oil from P. graciliflora .

Polyalthia is one of the largest genera in the Annonaceae family, and has been widely used in folk medicine for the treatment of rheumatic fever, gastrointestinal ulcer, and generalized body pain. The present investigation reports on the extraction by hydrodistillation and the composition of the essential oils of four Polyalthia species ( P. sumatrana , P. stenopetalla , P. cauliflora , and P. rumphii ) growing in Malaysia. The chemical composition of these essential oils was determined by gas chromatography (GC-FID) and gas chromatography-mass spectrometry (GC-MS). The multivariate analysis was determined using principal component analysis (PCA) and hierarchical clustering analysis (HCA) methods. The results revealed that the studied essential oils are made up principally of bicyclogermacrene (18.8%), cis -calamenene (14.6%) and β-elemene (11.9%) for P. sumatrana ; α-cadinol (13.0%) and δ-cadinene (10.2%) for P. stenopetalla ; δ-elemene (38.1%) and β-cubebene (33.1%) for P. cauliflora ; and finally germacrene D (33.3%) and bicyclogermacrene for P. rumphii. PCA score and HCA plots revealed that the essential oils were classified into three separated clusters of P. cauliflora (Cluster I), P. sumatrana (Cluster II), and P. stenopetalla, and P. rumphii (Cluster III) based on their characteristic chemical compositions. Our findings demonstrate that the essential oil could be useful for the characterization, pharmaceutical, and therapeutic applications of Polyalthia essential oil.

The rich and diversified Malaysian flora represents an excellent resource of new chemical structures with biological activities. The genus Xylopia L. includes aromatic plants that have both nutritional and medicinal uses. This study aims to contribute with information about the volatile components of three Xylopia species essential oils: Xylopia frutescens , Xylopia ferruginea , and Xylopia magna . In this study, essential oils were extracted from the leaves by a hydrodistillation process. The identification of the essential oil components was performed by gas chromatography (GC-FID) and gas chromatography–coupled mass spectrometry (GC-MS). The major components of the essential oils from X. frutescens were bicyclogermacrene (22.8%), germacrene D (14.2%), elemol (12.8%), and guaiol (12.8%), whereas components of the essential oils from X. magna were germacrene D (35.9%), bicyclogermacrene (22.8%), and spathulenol (11.1%). The X. ferruginea oil was dominated by bicyclogermacrene (23.6%), elemol (13.7%), guaiol (13.4%), and germacrene D (12.3%).

This study was aimed to investigate the chemical compositions of the essential oils from Goniothalamus macrophyllus and Goniothalamus malayanus growing in Malaysia. The essential oils were obtained by hydrodistillation and fully characterized by gas chromatography (GC–FID) and gas chromatography–mass spectrometry (GC–MS). Analyses of the essential oils from G. macrophyllus and G. malayanus resulted in 93.6 and 95.4% of the total oils, respectively. The major components of G. macrophyllus oil were germacrene D (25.1%), bicyclogermacrene (11.6%), α-copaene (6.9%) and δ-cadinene (6.4%), whereas in G. malayanus oil bicyclogermacrene (43.9%), germacrene D (21.1%) and β-elemene (8.4%) were the most abundant components.

Using hydrolysates of the North American prairie grass prairie cordgrass buffered at pH 4.5, 5.0, 5.5 or 6.0, xylitol production, xylitol yield, cell biomass production and productivity were investigated for three strains of yeast Candida . Of the three strains, the highest xylitol concentration of 20.19 g xylitol (g xylose consumed) −1 and yield of 0.89 g xylitol (g xylose consumed) −1 were produced by Candida mogi ATCC 18364 when grown for 120 h at 30° C on the pH 5.5-buffered hydrolysate-containing medium. The highest biomass level being 7.7 g cells (kg biomass) −1 was observed to be synthesized by Candida guilliermondii ATCC 201935 after 120 h of growth at 30° C on a pH 5.5-buffered hydrolysate-containing medium. The highest xylitol specific productivity of 0.73 g xylitol (g cells h) −1 was determined for C. guilliermondii ATCC 20216 after 120 h of growth at 30°C on a pH 5.0-buffered hydrolysate-containing medium. Xylitol production and yield by the three Candida strains was higher on prairie cordgrass than what was previously observed for the same strains after 120 h at 30° C when another North American prairie grass big bluestem served as the plant biomass hydrolysate indicating that prairie cordgrass may be a superior plant biomass substrate.