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2022 ◽  
Vol 42 ◽  
pp. 01007
Author(s):  
S.A. Sheremetova ◽  
S.N. Vityaz ◽  
E.B. Rotkina ◽  
S.I. Mikhailova

The article presents the materials of studies of the adventive flora of the Kemerovo region. For the territory of the Kemerovo region, we identified 244 alien species belonging to 162 genera and 50 families. As a result of the increasing process of invasion of new species into the territory of the region, the need for constant monitoring of alien species for the degree of their naturalization, especially in natural cenoses, is urgent. The problem of synanthropic plant species is becoming increasingly important not only for economically developed territories, but also for the relatively preserved mountain regions of Kuzbass. As a result of the studies, it was found that the synanthropic fraction of the Kuzbass flora, consisting of adventive and apophyte species, accounts for about 18% of the total composition of the flora of vascular plants in the Kemerovo region (60 apophyte species, 244 – advent ones). The revealed heterogeneity in the chorological, ecological and biological terms of the species of the adventive fraction makes it possible to find suitable conditions in various types of ecotopes on the territory of the Kemerovo region. This type of work can serve as a basis for developing a strategy for the preservation of natural phytosystems of Kuzbass.


Author(s):  
Juliana Olívia Nicolao ◽  
Franciana Aparecida Volpato Bellaver ◽  
Volmir Kist ◽  
Daniel Radin ◽  
Marcelo Mendes De Haro ◽  
...  

The factors that arouse interest in the study of essential oils as biocidal agents are numerous, such as the fact that they have antibacterial, antifungal, insecticidal, antioxidant, anti-inflammatory and larvicidal properties. The objective of this work was to evaluate the antimicrobial activity, in vitro, of the laurel (Laurus nobilis L) essential oil on the growth of pathogenic bacteria Salmonella enterica serovar Typhimurium ATCC 14028 and Staphylococcus aureus ATCC 25923, at different exposure times, as well as to perform the chemical characterization. Twenty compounds were identified and quantified, representing 96.57% of the total composition. The class of oxygenated monoterpenes represented the majority class of the essential oil, with 1,8-cineol (33.8%) as the substance found in greater quantity, followed by linalool (17.79%). The third constituent in greater quantity was sabinene (12.23%), belonging to the group of monoterpene hydrocarbons. Terpinyl acetate (9.41%) was also considered to be quantitatively representative. Laurel essential oil showed bacteriostatic activity against S. Typhimurium ATCC 14028 and S. aureus ATCC 25923.


Molecules ◽  
2021 ◽  
Vol 26 (23) ◽  
pp. 7283
Author(s):  
Basma Najar ◽  
Ylenia Pieracci ◽  
Claudio Cervelli ◽  
Guido Flamini ◽  
Luisa Pistelli

Helichrysum decorum DC, Helichrysum lepidissimum S. Moore, and Helichrysum umbraculigerum are three species traditionally used in the South African medicine. The present work deals with the investigation of the spontaneous emission and the essential oils obtained from these plants cultivated in open field under uniform conditions. Fractions of the volatile organic compounds of the three species were rich in monoterpene hydrocarbons, representing more than 70% of the total composition. Pinene isomers were the most representative compounds: β-pinene in H. decorum (53.0%), and α-pinene in H. lepidissimum (67.9%) and H. umbraculigerum (54.8%). These latter two species evidenced an important amount of sesquiterpene hydrocarbons (SH) especially represented by γ-curcumene (H. lepidissimum) and α- and β-selinene (H. umbraculigerum). On the contrary, in the EOs, sesquiterpenes compounds prevailed, representing more than 64% of the identified fraction to reach more than 82 and 87% in H. umbraculigerum and H. lepidissimum, respectively. Although the chemical classes and their relative abundances were comparable among the three species, the individual compounds of EOs showed large differences. In fact, caryophyllene oxide (26.7%) and γ-curcumene (17.4%) were the main constituents in H. decorum, and H. lepidissimum respectively, while neo-intermedeol (11.2%) and viridiflorol (10.6%) characterized H. umbraculigerum.


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4608
Author(s):  
Eduardo Valarezo ◽  
Génesis Gaona-Granda ◽  
Vladimir Morocho ◽  
Luis Cartuche ◽  
James Calva ◽  
...  

Croton ferrugineus Kunth is an endemic species of Ecuador used in traditional medicine both for wound healing and as an antiseptic. In this study, fresh Croton ferrugineus leaves were collected and subjected to hydrodistillation for extraction of the essential oil. The chemical composition of the essential oil was determined by gas chromatography equipped with a flame ionization detector and gas chromatography coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against three Gram-positive bacteria, one Gram-negative bacterium and one dermatophyte fungus. The radical scavenging properties of the essential oil was evaluated by means of DPPH and ABTS assays. The chemical analysis allowed us to identify thirty-five compounds representing more than 99.95% of the total composition. Aliphatic sesquiterpene hydrocarbon trans-caryophyllene was the main constituent with 20.47 ± 1.25%. Other main compounds were myrcene (11.47 ± 1.56%), β-phellandrene (10.55 ± 0.02%), germacrene D (7.60 ± 0.60%), and α-humulene (5.49 ± 0.38%). The essential oil from Croton ferrugineus presented moderate activity against Candida albicans (ATCC 10231) with an MIC of 1000 μg/mL, a scavenging capacity SC50 of 901 ± 20 µg/mL with the ABTS method, and very strong antiglucosidase activity with an IC50 of 146 ± 20 µg/mL.


Molecules ◽  
2021 ◽  
Vol 26 (15) ◽  
pp. 4613
Author(s):  
Eduardo Valarezo ◽  
Vladimir Morocho ◽  
Luis Cartuche ◽  
Fernanda Chamba-Granda ◽  
Magdaly Correa-Conza ◽  
...  

Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography–gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the principal constituent in male (28.24 and 25.90%) and female (26.47 and 23.90%) essential oil. Other main compounds were methyl chavicol, germacrene D, methyl eugenol, and α-pinene. Female essential oil presented a strong activity against Klebsiella pneumoniae (ATCC 9997) with an minimum inhibitory concentration (MIC) of 500 μg/mL and a scavenging capacity SC50 of 800 µg/mL.


Symmetry ◽  
2021 ◽  
Vol 13 (7) ◽  
pp. 1259
Author(s):  
Maksymilian Dziura ◽  
Basel Mansour ◽  
Mitchell DiPasquale ◽  
P. Charukeshi Chandrasekera ◽  
James W. Gauld ◽  
...  

In this review, we delve into the topic of the pulmonary surfactant (PS) system, which is present in the respiratory system. The total composition of the PS has been presented and explored, from the types of cells involved in its synthesis and secretion, down to the specific building blocks used, such as the various lipid and protein components. The lipid and protein composition varies across species and between individuals, but ultimately produces a PS monolayer with the same role. As such, the composition has been investigated for the ways in which it imposes function and confers peculiar biophysical characteristics to the system as a whole. Moreover, a couple of theories/models that are associated with the functions of PS have been addressed. Finally, molecular dynamic (MD) simulations of pulmonary surfactant have been emphasized to not only showcase various group’s findings, but also to demonstrate the validity and importance that MD simulations can have in future research exploring the PS monolayer system.


Author(s):  
Tran Hau Khanh ◽  
Pham Hong Ban ◽  
Tran Minh Hoi

Chemical composition of essential oils obtained from the leaf of Syzygium bullockii and Syzygium tsoongii were reported, corresponding oil content 0,36% and 0,27%. The analysis was performed by means of gas chromatography-flame ionization detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). Twenty-seven components were identified in leaf oil of Syzygium bullockii, which represented about 76,75% of the total composition of the oil and six components were not identified, which represented 15,72%. The major constituents of the essential oil were (E)-caryophyllene (49,65%), spathulenol (4,29%), caryophyllene oxide (4,14%), bicyclogermacrene (3,35%), 2-tridecanone (3,25%). Fourty-six components were identified in leaf oil of Syzygium tsoongii, which presented about 99.71% of the total composition of the oil. The major constituents of the essential oil were E-caryophyllene (23,40%), bicyclogermacrene (21,23%), (Z)-β-ocimene (10,61%), α-humulene (6,33%), (E)-β-ocimene (4,99%). For the first time, the chemical compositions of the essential oils of Syzygium bullockii and Syzygium tsoongii from Vietnam were being reported.  


Molecules ◽  
2021 ◽  
Vol 26 (13) ◽  
pp. 3961
Author(s):  
Eduardo Valarezo ◽  
Antoine Vullien ◽  
Dayra Conde-Rojas

Ocotea quixos (Lam.) Kosterm. is an aromatic tree native to Ecuador, whose leaves are used to prepare aromatic beverages to which different health benefits are attributed. In this study, Ocotea quixos leaves were collected in the Amazon region in different environmental conditions and subjected to hydrodistillation to isolate the essential oil. The collection variables used were type of soil, amount of shade, and height; in addition, the presence of twig and leaf age and moisture were used as variables. Chemical composition was analyzed by means of gas chromatography equipped with a flame ionization detector and gas chromatography coupled to mass spectrometry. A wide variety of chemical compositions were detected in the samples. In total, forty-seven compounds were identified, which represented between 97.17% and 99.89% of the total composition. The constituents were mainly grouped into aliphatic sesquiterpene hydrocarbons (33.03–55.89%), other compounds (8.94–47.83%), and oxygenated monoterpenes (1.97–39.66%). The main constituents were found to be (E)-cinnamyl acetate (5.96–41.65%), (E)-methyl cinnamate (0.38–37.91%), and trans-caryophyllene (8.77–37.02%). The statistical analysis suggested the existence of two essential oil chemotypes and a direct correlation between environmental conditions and chemical composition of the essential oils.


2021 ◽  
Vol 19 (1) ◽  
pp. 87-112
Author(s):  
Kristel Zilmer

Crosses on Swedish rune-stones have been studied on numerous occasions, mostly in isolation from other features of the monument. This article exam- ines the use of rune-stone crosses with an emphasis upon their varying functions in the total composition of runic monuments. The analysis that combines the level of visual composition with textual elements re- veals different strategies in the display of crosses. Be- sides functioning as externalized Christian markers, crosses could be made to serve various internal (i.e. inscription-based) stylistic, decorative and practical purposes. The role of the cross could be modified ac- cording to particular contexts of usage.


2021 ◽  
Vol 15 (4) ◽  
pp. 301-312
Author(s):  
Arafa Musa ◽  
Khaled F. El-Massry ◽  
Ahmed H. El-Ghorab ◽  
Amr Farouk ◽  
Hazim M. Ali ◽  
...  

The hydrodistilled volatile constituents of Cistanche tubulosa (commonly known as Desert Ginseng) have been chemically and biologically investigated. Based on the retention times and mass fragmentation of the obtained GC-MS chromatogram, 106 individual components which representing ≈ 99.29 % of the total volatile constituents have been identified. The major compounds (66.57% of the total composition) were identified as hexanal (15.98%), trans-sabinyl acetate (12.22%), allo-aromadendrene (9.30%), nonanoic acid (6.66%), 3Z- hexeny-2-methyl butanoate (6.09%), valeranone (5.25%), (E, E)-α-Farnesene (3.18%), a-pinene (3.06%), linalool isovalerate (3.03%) and a-humulene (1.8%). Estimation of the antioxidant activity of EO showed promising effect at 80 mg/mL concentration, it exerted 62.40, 863.29 and 62.72 % inhibition compared to TBHQ that showed 78.62, 77.56 and 79.23 % inhibition using DPPH, ABTS and β-carotene/Linoleic acid, respectively. The antioxidant activity was pronounced at 80 mg/mL than other concentrations. The volatile constituents showed inhibitory activity against gram positive bacteria ranged from 2.23 mg/100 mL ( for staphylococcus aureus ), and 15.68 mg/100 mL (for Bacillus cereus) compared to ciprofloxacin which showed inhibitory activity 0.185, and 0.182 mg/100 mL, respectively. Moreover, the MIC of volatiles towards gram negative bacteria are ranged from 18.35 (Escherichia coli) to 31.61 mg/100 mL (Klebsiella pneumonia) compared to ciprofloxacin with 0.184 to 0.188 mg/mL respectively. Additionally, the antifungal activity against candida albicans was rather promising (4.36 mg/mL).


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