111 research outputs found
An update review of biological activity of essential oils from Curcuma genus
Curcuma L. is one of the largest genera (about 108 species) belonging to Zingiberaceae family. Many Curcuma plants have been used for many purposes, including possessing preservative, flavoring, and medicinal properties. Curcuma plants are a prominent material for extracting essential oils (EOs). Over the last five years, many studies have been reported for the biological effects of the EOs isolated from Curcumaplants such as antimicrobial, antioxidant, anti-inflammation, anti-trypanosomal, antileishmanial, anti?acetylcholinesterase, antiproliferative, cytotoxic, larvicidal, and insecticidal activities. In this brief review, an updated version of the bioactivities of EOs from different species belonging to Curcuma genus are presented
Chemical profiles and biological activities of essential oils of Arisaema and Homalomena species (Araceae) – A review
In this review, the chemical compositions and bioactivities of the essential oils isolated from Arisaema and Homalomena species, two large genera belonging to the Araceae family, have been reported for the first time. Accordingly, the essential oils isolated from the plants of two genera consisted of some chemical groups, including monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, and oxygenated sesquiterpenes, etc. In addition, the essential oils and their major compounds isolated from Arisaema and Homalomena plants possessed biological activities, including antimicrobial, insecticidal, nematicidal, antiproliferative, larvicidal and anthelmintic activities. This review mainly provides information on the Arisaema and Homalomena oils which are able to use as a guide for the collection of the species with the best chemical composition and biological activities
A review on chemical profiles and biological activities of essential oil from some plants belonging to family Scrophulariaceae
Scrophulariaceae is a large family, many species of which have been reported to have a wide range of biological activities and uses as folk medicines. The essential oils from species belonging to this family mainly contain monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpene hydrocarbons, oxygenated sesquiterpenes and non-terpenes. Furthermore, their essential oils have been reported to have a variety of biological activities such as antimicrobial, antioxidant, insecticidal etc. The objective of this review is to provide a brief overview of the chemical composition and biological activities of the essential oils isolated from different parts of species included in the Scrophulariaceae family. In addition, this paper also introduces the therapeutic potentials and provides the evidence for future medicinal applications of those species
Chemical composition and antibacterial activities of the ethanol extracts from the leaves and tubers of Amorphophallus pusillus
Amorphophallus pusillus is a rare species which is found only in Binh Chau-Phuoc Buu Nature Reserve. In this study, we determined 7 flavonoid compounds in tuber and leaf of A. pusillus, including of vitexin, orientin, vitexin 2?-O-glucoside, cyanidin 3-O-rutinoside, pelargonidin 3-O-glucoside, schaftoside, and peonidin 3-O-rutinoside via liquid chromatography-mass spectrometry (LC-MS). Furthermore, we have proved the antibacterial activities of ethanol extracts obtained from A. pusillus leaves and tubers in the first time. The data revealed that ethanol extracts could inhibit the growth of 6 tested microorganisms, such as Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Salmonella enteritidis, Salmonella typhimurium, and Staphylococcus aureus. These data suggested the potential application of ethanol extracts isolated from this species as natural antimicrobial agents for treatment of infection caused by bacteria, especially in dermatologic and enteric infections
TAXONOMIC IDENTITY OF ARISAEMA CONDAOENSE (ARACEAE) BASED ON NEW MORPHOLOGICAL AND MOLECULAR DATA
Arisaema condaoense V.D. Nguyen was described as a new species from Con Dao National Park, Ba Ria–Vung Tau Province, Vietnam in 2000. However, this species has been suspected of being a form of Arisaema roxburghii Kunth, a species widespread in the whole Indochina and Malay Peninsula. This was due to the original description based on dried specimens with male inflorescences only. Morphological characteristics of female inflorescences, which are of taxonomical importance to identify the species, have not been known. In June 2015, we re-sampled the plant in Con Dao National Park with both male and female inflorescences for detailed examination of morphological characteristics. Besides, the matK gene of the chloroplast genome of this species was sequenced to analyse its phylogenetic relationship with other Arisaema species. The gathered morphological and molecular data indicate that A. condaoense is certainly a distinct species, not a synonym of A. roxburghii. The noted morphological characteristics also provide key differences to distinguish A. condaoense from two other morphologically close species of sect. Fimbriata (i.e A. maxwellii from Thailand and A. pierreanum from Vietnam which also share yellow spathes and several other characteristics in common), which are supported by the molecular data. Thus, the species is endemic to Con Dao National Park in Ba Ria–Vung Tau Province, Vietnam. Furthermore, this study allows us revising the description of A. condaoense with, for the first time, supplemental key taxonomic characteristics and illustrating colourful photographs taken from the fresh materials. A key to all eight known Vietnamese species of sect. Fimbriata is also given
Antibacterial activities of ethanolic extract of four species of Rutaceae family
In this study, the antibacterial activity of ethanolic extract from the leaves of four Rutaceae species, including Acronychia pedunculata, Clausena excavata, Glycosmis pentaphylla and Luvunga scandens, were performed using the agar disk diffusion method for the first time. The ethanolic extracts from the leaves of A. pedunculata and G. pentaphylla were able to resist against all six bacterial strains with zones of inhibition for Bacillus cereus (17.3±2.1 mm, 20.8±1.0 mm) Staphylococcus aureus (8.5±0.5 mm, 17.6±0.3 mm) Escherichia coli (16.7±2.1 mm, 15.3±1.2 mm), Pseudomonas aeruginosa (11.7±0.6 mm, 14.0±1.7 mm), Salmonella enteritidis (22.3±0.6 mm, 24.6±0.5 mm) and Salmonella typhimurium (9.5±0.9 mm, 8.3±0.6 mm). On the other hand, the ethanolic extract of C. excavata leaf was resistant to B. cereus (12.3±0.6 mm), S. aureus (11.6±0.5 mm), E. coli (11.5±2.1 mm), P. aeruginosa (10.6±0.3 mm) while B. cereus (8.2±0.3 mm), S. aureus (9.3±0.6 mm), E. coli (8.5±0.5 mm) and S. typhimurium (8.3±0.6 mm) were inhibited by the ethanolic extract of L. scandens leaf. This study could provide necessary information for further application of these species in medicine
Analysis of the effect of spray mode on coating porosity and hardness when spraying press screws by the high velocity oxy fuel method
Porosity and coating hardness are two very important properties of the coating. In order to achieve low coating porosity and high hardness, a suitable spray mode is desired. In the particular application for press screws with the complex surface, a suitable spray mode plays a significant role in the formation of the coating properties. This paper employs the Taguchi experimental design method combined with ANOVA analysis to evaluate the impact of the spray mode on the porosity and hardness of the coating while spraying the screw surface using the High Velocity Oxy Fuel (HVOF) method. The injection material used is WC HMSP1060-00 +60 % 4070, with its main components being Nickel and Carbide Wolfram. And the press screw material is 1045 steel. The impactful parameters of the spray mode investigated and tested are the flow rate of spray (F) with a range varying from 25 g/min to 35 g/min, spray distance (D) with a range of values varying from 0.25 m to 0.35 m, and an oxygen/propane ratio (R) from 4 to 6. The analysis shows that the spray mode significantly affects the coating properties, and a suitable set of spray parameters is found to achieve low coating porosity and high coating hardness. The spray mode with the lowest porosity is achieved at a spray rate (F) of 35 g/min, a spray distance (D) of 0.3 m, and an oxygen/propane ratio (R) of 6. The interactions between D and R, as well as between F and D, are statistically significant, influencing each other's effects on porosity. However, the interaction between F and R is relatively low, indicating that changes in one parameter have less impact on porosity when the other parameter is varied. Similarly, for the highest coating hardness, the optimal spray mode includes an F of 35 g/min, D of 0.25 m, and R of 6. There is a significant interaction between F and D, while the interaction between F and R is relatively low. Notably, there is no interaction between F and
Molecular phylogeny of Annonaceae species from Binh Chau-Phuoc Buu Nature Reserve based on two chloroplast gene regions
In this study, based on molecular biology techniques, the matK and trnL-F regions of ten Annonaceae species grown in Binh Chau-Phuoc Buu Nature Reserve, Vietnam were successfully amplified and sequenced for the first time. Along with other highly homologous DNA sequences from the GenBank database, the molecular phylogeny of ten studied species was also established. By using the alignment tool of NCBI database, the percentage of identity among sequences of studied species was also presented. The study aims to partially contribute to the further understanding of the evolutionary relationships among Annonaceae species
Outage probability analysis for hybrid TSR-PSR based SWIPT systems over log-normal fading channels
Employing simultaneous information and power transfer (SWIPT) technology in cooperative relaying networks has drawn considerable attention from the research community. We can find several studies that focus on Rayleigh and Nakagami-m fading channels, which are used to model outdoor scenarios. Differing itself from several existing studies, this study is conducted in the context of indoor scenario modelled by log-normal fading channels. Specifically, we investigate a so-called hybrid time switching relaying (TSR)-power splitting relaying (PSR) protocol in an energy-constrained cooperative amplify-and-forward (AF) relaying network. We evaluate the system performance with outage probability (OP) by analytically expressing and simulating it with Monte Carlo method. The impact of power-splitting (PS), time-switching (TS) and signal-to-noise ratio (SNR) on the OP was as well investigated. Subsequently, the system performance of TSR, PSR and hybrid TSR-PSR schemes were compared. The simulation results are relatively accurate because they align well with the theory
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