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Camphene (C10H16) also-called2,2-dimethyl-3-methylidenebicyclo[2.2.1] heptane is a volatile compound belonging to the terpenoid family, in particular to the group of monoterpene hydrocarbons. It is...

Hinokitiol is a natural bioactive compound found in several aromatic and medicinal plants. It is a terpenoid synthetized and secreted by different species as secondary metabolites. This volatile compound was tested and explored for its different biological properties. In this review, we report the pharmacological properties of hinokitiol by focusing mainly on its anticancer mechanisms. Indeed, it can block cell transformation at different levels by its action on the cell cycle, apoptosis, autophagy via inhibiting gene expression and dysregulating cellular signaling pathways. Moreover, hinokitiol also exhibits other pharmacological properties, including antidiabetic, anti-inflammatory, and antimicrobial effects. It showed multiple and several effects through its inhibition, interaction and/or activation of the main cellular targets inducing these pathologies.

Thanks to their promising properties, essential oils (EOs) have strong potential to remedy several problems such as microorganisms acquired resistance to antimicrobial agents and chemical antioxidants toxicity. Firstly, this work was conducted to determine chemical composition, antioxydant activity, then antibacterial, antifungal, antimycobacterial properties of Rosmarinus officinalis EO. Secondly, EOs combined antimicrobial effect with carvacrol was assessed. Chemical EO analysis was performed using Gas chromatography/mass spectrometer. 1,1-diphenyl-2-picrylhydrazyl test was used to evaluate in vitro antioxidant rosemary oil effect. The antimicrobial activity against seven bacteria, two fungi, and two mycobacterial strains was screened using the broth microdilution method. Thereafter, the checkerboard essay was used to evaluate the antibacterial effect of this EO and Carvacrol. Chemical EO analysis revealed 1,8-cineole (33.88%), camphor (14.66%), and α-pinene (12.76%) as main constituents. The obtained IC50 value (2.77 mg/mL) showed rosemary EO's radical scavenging power. Moreover, all tested microorganisms showed an important sensitivity to this EO (MIC values: 0.007%-1% (v/v)). Furthermore, results highlighted synergistic and partial synergistic interaction for tested products. The studied EO has both antimicrobial and antioxidant potentials. Combined application showed a remarkable synergistic antibacterial potentiation that can be used as an alternative in pharmaceutical and food processing sectors.

Ziziphus lotus (Nbeg) is very common in Morocco where it occupies various ecosystems and presents different interests; however it remains devalued and knows recent deterioration due to the human pressure through clearing, wood collection, irrational cuts’ exploitation and overgrazing. This study aims to prepare activated carbon from the cores of this interesting biomaterial, for the first time to the best of our knowledge, according to a manufacturing process based on its chemical and thermal activation. The cores of Ziziphus lotus (Nbeg) were chemically activated by sulfuric acid (H2SO4, 98%) for 24h with a mass contribution (1:1), and then carbonized at a temperature of 500 °C for 2 hours. The obtained activated carbon was characterized by scanning electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy and specific surface measurement. These characterization results showed an important porosity and a surface structure having acid groups and carboxylic functions. The adsorption of methylene blue (MB) was evaluated, by Langmuir and Freundlich models examination, in order to explain the adsorption efficiency in a systematic and scientific way. Also pseudo-first order and pseudo-second order kinetic models were used to identify the possible mechanisms of this adsorption process. The results showed that the MB adsorption process on activated carbon follows the Langmuir model and that the adsorption kinetic is best represented by kinetics data of the pseudo-second order model. Therefore, Z. lotus can be used as a low-cost available material to prepare a high quality activated carbon having a promising potential in the wastewater treatment.

Background Plant growth-promoting rhizobacteria (PGPR) are known to improve plant growth and are used as biofertilizers, thanks to their numerous benefits to agriculture such as phosphorus solubilization and phytohormone production. In this paper, four rhizospheric bacteria (Phyllobacterium sp., Bacillus sp., Agrobacterium sp., and Rhizobium sp.) isolated from surface-sterilized root nodules of Acacia cyanophylla were tested for their ability to solubilize inorganic phosphate and to produce indole-3-acetic acid (IAA) under laboratory conditions. Then, the best IAA producer (Rhizobium sp.) was selected to test optimized conditions for IAA production. Finally, the effect of the four strains on plant growth for A. cyanophylla was evaluated in vivo. Results The results showed that the totality of the tested isolates had solubilized inorganic phosphate (P) in both NBRIP (National Botanical Research Institute Phosphate) and PVK (Pikovskaya) media. Bacillus sp. was a high P-solubilizer and showed maximum solubilization in PVK (519 μg ml-1) and NBRIP (782 μg ml-1). The optimization of maximum phosphate solubilization was done using different sources of carbon (1%) and nitrogen (0.1%). Glucose and ammonium sulfate were selected to be the best carbon and nitrogen source for phosphate solubilization by all tested strains, except for Phyllobacterium sp., which recorded the highest phosphate solubilization with ammonium nitrate. The IAA production by the tested strains indicated that Rhizobium sp. produced the highest amount of IAA (90.21 μg ml-1) in culture media supplemented with L-tryptophan. The best production was observed with L-Trp concentration of 0.2% (116.42 μg ml-1) and at an initial pH of 9 (116.07 μg ml-1). The effect of NaCl on IAA production was tested at concentrations of 0 to 5% and the maximum production of 89.43 μg ml-1 was found at 2% NaCl. The extraction of crude IAA from this strain was done and purity was confirmed with Thin Layer Chromatography (TLC) analysis. A specific spot from the extracted IAA production was found to correspond with a standard spot of IAA with the same Rf value. Finally, the tested PGPR demonstrated growth stimulatory effects on Acacia cyanophylla seedlings in vivo, with a great increase of shoots’ and roots’ dry weights, and shoot length compared to control. The rhizobacterial isolates were identified by 16S rDNA sequence analysis as Agrobacterium sp. NA11001, Phyllobacterium sp. C65, Bacillus sp. CS14, and Rhizobium sp. V3E1. Conclusion This study highlights the importance of the use of phosphate solubilizing and IAA producer microorganisms as biofertilizers to increase crop yields. The studied strains showed a significant phosphate solubilization potential and IAA production. The use of selected strains as inoculants would be interesting, in particular with a view of promoting sustainable agriculture. However, further studies to verify the efficacy of the best isolates in situ is certainly required.

To increase the sensibility of Salmonella typhimurium strain, a mixture of Thymus vulgaris L. (T. vulgaris L.), Rosmarinus officinalis L. (R. officinalis L.) and Myrtus communis L. (M. communis L.) essential oils (EOs) was used in combined treatment by experimental design methodology (mixture design). The chemical composition of EOs was firstly identified by GC and GC/MS and their antibacterial activity was evaluated. The results of this first step have shown that thymol and borneol were the major compounds in T. vulgaris and M. communis L. EOs, respectively, while 1,8-cineole and α-pinene were found as major compounds in R. officinalis L. The same results have shown a strong antibacterial activity of T. vulgaris L. EO followed by an important power of M. communis L. EO against a moderate activity of R. officinalis L. EO. Besides, 1/20 (v/v) was the concentration giving a strain response classified as sensitive. From this concentration, the mixture design was performed and analyzed. The optimization of mixtures antibacterial activities has highlighted the synergistic effect between T. vulgaris L. and M. communis L. essential oils. A formulation comprising 55% of T. vulgaris L. and 45% of M. communis L. essential oils, respectively, can be considered for the increase of Salmonella typhimurium sensibility.

In this study, we investigated the potential adhesion of marine bacteria isolated from seawater in the port of Chmaâla, Morocco, to sea-immersed 304 and 316 stainless steels using thermodynamic approach and the Environmental Scanning Electron Microscopy (ESEM). Furthermore, the physicochemical properties including hydrophobicity and electron donor / electron acceptor (Lewis acid-base) of bacterial isolates and both substrates were evaluated using the contact angle measurements. The molecular identification indicated that the isolated strains were Bacillus thuringiensis and Bacillus amyloliquefascience. Results also showed that both bacterial strains’s cells have a hydrophilic character with ΔGiwi values of 29.30 and 24.12 mJ m−2 respectively for Bacillus thuringiensis and Bacillus amyloliquefascience, and are strong electron donating (γ−) and weakly electron accepting (γ+). For substrates surfaces, we found that both sea-immersed stainless steels types were hydrophilic and present strong electron-...

Background The production of indole-3-acetic acid (IAA) is an essential tool for rhizobacteria to stimulate and facilitate plant growth. For this, eighty rhizobial bacteria isolated from root nodules of Acacia cyanophylla grown in different regions of Morocco were firstly screened for their ability to produce IAA. Then, IAA production by a combination of isolates and the inoculation effect on the germination of Acacia cyanophylla seeds was studied using the best performing isolates in terms of IAA production. The best IAA producer bacterial isolate (I69) was selected to optimize IAA production using response surface methodology based on the central composite design. Results Results showed that the majority of tested isolates were able to produce IAA with a relatively higher concentration of 135 μg/ml for the isolate I69, followed by isolates I22 and I75 with respective concentrations of 116 μg/ml and 105 μg/ml IAA. The IAA production and the seed germination rate were relatively increased by the synergistic effect of I69 and I22. Later, response surface methodology was used to determine optimal operating conditions leading to IAA production optimization. Thus, an incubation temperature of 36 °C, a pH of 6.5, an incubation time of 1 day, and respective tryptophan and NaCl concentrations of 1 g/l and 0.1 g/l were optimal parameters leading to 166 μg/ml IAA which was the maximal produced concentration. Conclusion The present study highlighted that IAA-producing rhizobacteria could be harnessed to improve plant growth. Furthermore, their production can be easily controlled using response surface methodology, which represents a very useful tool for optimization.

Our objective in this work is evaluated the antibacterial, antifungal and antioxidant activity of the phytochymic compounds of the roots and leaves of a species Withania frutescens. In the first part, the phenolic compound is determinate by the Folin-Ciocalteau reaction, the richness of the roots in polyphenols (53.33 ± 1.20 mg EGA/g Extract) is six times higher than that of the leaves. The antioxidant test is evaluated by four methods: DPPH test, reducing power test (FRAP), total antioxidant capacity (CAT) and the s-carotene discoloration test. The IC-50 values of the DPPH test of the studied parts are of the order of 0.36 µg/ml and 6.63 µg/ml, which showed a lower anti-free radical activity than that of BHT (0.12 µg/ml). The results obtained by the FRAP method revealed a low reducing power of iron for two extracts (EC-50 of 0.45%) compared to Quercetine (EC-50 of 0.03%). The compounds of root and leaf extracts have a significant total antioxidant capacity, respectively 477.65 ± 37.60 and 317.03 ± 46.64 mg EAA/g Extract. In the β-carotene discoloration test, extracts from the aerial and underground parts showed antioxidant activity of 57% followed by (36%), respectively. The evaluation of the antibacterial activity of in vitro extracts against microorganisms is carried out by two methods: disc diffusion and microdilution. The results show that the extracts exert an intermediate inhibitory effect (inhibition diameter between 8 and 15 mm, the smallest MIC obtained is 2.80 mg/ml) on all strains tested. The antifungal activity was estimated by determining the growth inhibition rate of the fungus tested. Indeed, the compounds studied exhibit a good antifungal effect since the minimum inhibitory concentration (MIC) of 4.5 mg/ml for root extract and 9 mg/ml for leaf extract.

In the aim of valorizing aromatic and medicinal plants from Morocco, this work focuses on the chemical characterization and antimicrobial activity of Pelargonium asperum essential oil against 11 microbial strains causing problems in the medical and food domain. The chemical profile of the volatile oil was investigated by GC/MS. The major compounds were citronellol (26.98%), geraniol (14.12%), isomenthone (8.80%), linalool (4.97%), citronellyl formate (3.1%), followed by geranyl formate (4.07%) and guai-6,9-diene (4.24%). The results of antimicrobial activity by using the broth microdilution method indicated that essential oil of Pelargonium asperum exhibited significant antimicrobial activity against all tested microorganisms with the strongest inhibitory effect against yeasts. The MICs values ranged from 0.003% to 0.25% (v/v) for all strains, except Pseudomonas aeruginosa, which was least susceptible and inhibited by 2% (v/v). These results suggest that Pelargonium asperum oil could be used for the development of new antimicrobial agents.

Hexavalent chromium Cr(VI) is a widespread environmental contaminant. Many microorganisms have been reported to detoxify hexavalent chromium. The present work is the first report of a strain of Enterococcus having the ability of resistance to and reduction of Cr(VI). This strain was isolated from tannery waste-contaminated soil and identified as Enterococcus gallinarum, by biochemical methods and 16S rDNA analysis. The strain also exhibited multiple heavy metals (Cu2+, Ni 2+, Pb2+, Co2+ and Zn2+) tolerance. It was found to reduce chromate to 100% at a concentration of 200 mg l-1, in aerobic conditions. The cells reduced Cr(VI) under a wide range of temperatures (25-45°C) and pH (7–11) with optimum at 37°C and initial pH 10. The presence of other metals, such as Cu2+, stimulated Cr(VI) reduction, while Pb2+ and Ni 2+ had no significant effect on reduction ability by the strain. Assay with resting and permeabilized cells (treated with toluene and Triton X-100) demonstrated that the reduction of Cr(VI) is mediated by cell membrane bound or soluble proteins of the cell. The results obtained in this study have significance for the bioremediation of chromate pollution.

Objective To evaluate the susceptibility of Mycobacterium aurum and Mycobacterium smegmatis in vitro to the essential oils obtained from two medicinal plants: Thymus satureioides ( T. satureioides ) and Mentha pulegium ( M. pulegium ), and to study their chemical composition. Methods The aerial parts of T. satureioides and M. pulegium (leaves and stems) were hydro-distillated using a Clevenger-type apparatus and essential oils were analyzed and identified by gas chromatography-mass spectrometry. Antimycobacterial screening of essential oils was performed on the basis of the inhibition zone diameter by disc diffusion method against two mycobacterial strains whereas the minimal inhibitory concentration and minimal bactericidal concentration were determined by using the micro-dilution method. Results Chemical analysis of their aerial part's essential oils gave as major compounds, borneol (34.26%), carvacrol (31.21%) and thymol (3.71%) for T. satureioides and R(+)-pulegone (75.48%), carvone (6.66%) and dihydrocarvone (4.64%) for M. pulegium . Thereafter their antimycobacterial effect evaluation, using the micro-dilution method, indicated that minimal inhibitory concentration values of T. satureioides essential oil ranged from 0.062% to 0.015% (v/v) and from 0.125% to 0.031% (v/v) for M. pulegium respectively against Mycobacterium aurum and Mycobacterium smegmatis . Conclusions It is clearly evident from the results obtained that the Moroccan medicinal plants have great potential to be used as anti-tuberculosis agents. These findings may help scientists to undertake several research projects to discover useful natural product as new anti-tuberculosis drug.