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Chemical diversity and biological activities of essential oils from native populations of Clinopodium menthifolium subsp. ascendens (Jord.) Govaerts
2021
Debbabi, Haïfa | El Mokni, Ridha | Nardoni, Simona | Chaieb, Ikbal | Maggi, Filippo | Nzekoue, Franks Kamgang | Caprioli, Giovanni | Hammami, Saoussen
This study is focused on the analysis of regional variation of the chemical compositions of three Clinopodium menthifolium subsp. ascendens (Jord.) Govaerts Tunisian accession, as well as their inhibition toward fungi and insect pests. The diversity of the chemical constituents and biological activities in front of the aforementioned variations was found to be remarkable. Essential oils were obtained by hydrodistillation of the aerial parts and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 41, 42, and 30 compounds were identified respectively from Clinopodium menthifolium essential oils harvested from three Tunisian regions, namely Ain-Draham (ADEO), Babouch (BEO), and Tabarka (TEO). All analyzed oils were rich in oxygenated monoterpenes with different major constituents. Piperitenone (34.5%), cis-piperitone oxide (26.1%), and pulegone (47.9%) were the dominant compounds in the three volatile oils, respectively. The antifungal activity was investigated in vitro using six targeted fungal strains (Aspergillus flavus, Aspergillus terreus, Candida albicans, Microsporum canis, Microsporum gypseum, and Trichophyton mentagrophytes). The toxicity and repellency of essential oils were evaluated against the stored product pest Tribolium confusum. The tested samples were differently effective toward the target fungi and the pest depending on the variability of their chemical compositions. BEO exhibited the highest fungitoxic properties toward A. terreus mold, M. canis dermatophyte, and C. albicans yeast (the MIC values ranged from 40 to 400 μg mL⁻¹). In addition, the data showed that TEO repelled T. confusum moderately (PR = 42.5% at 2 h after exposure). Concerning the contact treatment, both ADEO and BEO were proved to possess slightly toxic effects toward T. confusum pest (% of mortality 27.5–32.5% at 5% concentration). The results showed that the geographic origin greatly influenced the chemical composition and the associated bioactivities of Clinopodium menthifolium subsp. ascendens.
Afficher plus [+] Moins [-]Increase in Total Petroleum Hydrocarbons Removal Rate in Contaminated Mining Soil Through Bioaugmentation with Autochthonous Fungi During the Slow Bioremediation Stage
2021
Hernández-Adame, N. M. | López-Miranda, J. | Martínez-Prado, M. A. | Cisneros-de la Cueva, S. | Rojas-Contreras, J. A. | Medrano-Roldán, H.
The removal of total petroleum hydrocarbons (TPHs) from contaminated mining soil was carried out under in vitro conditions. The aerobic consumption of TPH in the slow bioremediation stage via biostimulation with native microorganisms and biostimulation-bioaugmentation with autochthonous fungal isolates was evaluated. The initial TPH concentration was 70,880 ± 975 mg TPH/kg soil, soil was amended with nutrients at a C:N:P ratio of 100:15:1, the water content was adjusted to the soil field capacity, and batch microcosm reactors were incubated at room temperature (20.5 ± 3.1°C) for 90 days. The bioaugmentation process was tested using four hydrocarbonoclastic fungal strains isolated from the same contaminated mining soil individually and a mixed culture of the four isolates. The molecular characterization of the isolated fungi was based on sequence analysis of 18S rRNA, and the fungi were identified as Aspergillus niger MT786339.1, Aspergillus fumigatus MT786338.1, Aspergillus terreus MT786341.1, and Aspergillus flavus MT786340.1. The best TPH removal was achieved by inoculation with the fungal consortium (57 ± 1.97%) at 45 days (slow stage) after initiating the biostimulation process, followed by inoculation with Aspergillus niger (49 ± 1.2%), Aspergillus terreus (44 ± 0.67%), Aspergillus fumigatus (35 ± 0.98%), and Aspergillus flavus (32 ± 0.38%), while the degradation rate achieved with native microorganisms was only 21.6 ± 1.5%; statistical analysis of the results showed significant differences.
Afficher plus [+] Moins [-]Ecofriendly Method for Bioremediation of Chlorpyrifos from Agricultural Soil by Novel Fungus Aspergillus terreus JAS1
2013
Silambarasan, Sivagnanam | Abraham, Jayanthi
Biodegradation of chlorpyrifos was studied in mineral medium and soil with a novel fungal strain JAS1 isolated from a paddy field soil. The molecular characterization based on 18S rRNA sequence homology confirmed its identity as Aspergillus terreus. The 300-mg L⁻¹ chlorpyrifos and its major metabolite 3,5,6-trichloro-2-pyridinol (TCP) were completely degraded within 24 h of incubation in the mineral medium. In soil enriched with chlorpyrifos and nutrients (carbon, nitrogen, and phosphorous), A. terreus JAS1 was able to degrade chlorpyrifos and its metabolite TCP (300 mg kg⁻¹ soil) in 24 and 48 h, respectively. The soil was spiked with chlorpyrifos (300 mg kg⁻¹ soil) devoid of nutrients and the fungal strain was capable of degrading both chlorpyrifos and TCP in 24 and 48 h, respectively. The course of the degradation process was studied using high-performance liquid chromatography and Fourier transform infrared analyses. These results showed that the chlorpyrifos-degrading fungal strain had the potential to degrade the pesticide-contaminated agricultural soils even without addition of nutrients.
Afficher plus [+] Moins [-]Insecticidal potency of Aspergillus terreus against larvae and pupae of three mosquito species Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti
2015
Ragavendran, Chinnasamy | Natarajan, Devarajan
Microbial control agents offer alternatives to chemical pest control, as they can be more selective than chemical insecticides. The present study evaluates the mosquito larvicidal and pupicidal potential of fungus mycelia using ethyl acetate and methanol solvent extracts produced by Aspergillus terreus against Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti. The A. terreus mycelia were extracted after 15 days from Sabouraud dextrose broth medium. The ethyl acetate extracts showed lethal concentration that kills 50 % of the exposed larvae (LC₅₀) and lethal concentration that kills 90 % of the exposed larvae (LC₉₀) values of the first, second, third, and fourth instar larvae of An. stephensi (LC₅₀ = 97.410, 102.551, 29.802, and 8.907; LC₉₀ = 767.957, 552.546, 535.474, and 195.677 μg/ml), Cx. quinquefasciatus (LC₅₀ = 89.584, 74.689, 68.265, and 67.40; LC₉₀ = 449.091, 337.355, 518.793, and 237.347 μg/ml), and Ae. aegypti (LC₅₀ = 83.541, 84.418, 80.407, and 95.926; LC₉₀ = 515.464, 443.167, 387.910, and 473.998 μg/ml). Pupicidal activity of mycelium extracts was tested against An. stephensi (LC₅₀ = 25.228, LC₉₀ = 140.487), Cx. quinquefasciatus (LC₅₀ = 54.525, LC₉₀ = 145.366), and Ae. aegypti (LC₅₀ = 10.536, LC₉₀ = 63.762 μg/ml). At higher concentration (500 μg/ml), mortality starts within the first 6 h of exposure. One hundred percent mortality occurs at 24-h exposure. The overall result observed that effective activity against selected mosquito larvae and pupae after 24 h was a dose and time-dependent activity. These ensure that the resultant mosquito population reduction is substantial even where the larvicidal and pupicidal potential is minimal. The FTIR spectra of ethyl acetate extract reflect prominent peaks (3448.32, 3000.36, 2914.59, 2118.73, 1668.21, 1436.87, 1409.02, 954.33, 901.13, and 704.67 cm⁻¹). The spectra showed a sharp absorption band at 1314.66 cm⁻¹ assigned to wagging vibration of the C–H group. The band at 1023.59 cm⁻¹ developed for C–O and C=N, respectively, and was commonly found in carboxylic acid and amine groups. GC–MS analysis of ethyl acetate extracts showed the presence of six compounds, of which the major compounds were identified as n-hexadecanoic acid (15.31 %) and methyl 12,15-octadecadienoate (31.989 %), based on their peak molecular weight. The HPLC analysis result highlights that the A. terreus ethyl acetate extract was compared with pure n-hexadecanoic acid which resulted in similar retention time of 19.52 and 19.38, respectively. Thus, the active compound produced by this species would be more useful against vectors responsible for diseases of public health importance. This is the first report on mosquito larvicidal and pupicidal activity of ethyl acetate extract produced by A. terreus species.
Afficher plus [+] Moins [-]Enhancement of in vitro high-density polyethylene (HDPE) degradation by physical, chemical, and biological treatments
2014
Balasubramanian, V. | Natarajan, K. | Rajeshkannan, V. | Siddhuraju, P. (Perumal)
Partially degraded high-density polyethylene (HDPE) was collected from plastic waste dump yard for biodegradation using fungi. Of various fungi screened, strain MF12 was found efficient in degrading HDPE by weight loss and Fourier transform infrared (FT-IR) spectrophotometric analysis. Strain MF12 was selected as efficient HDPE degraders for further studies, and their growth medium composition was optimized. Among those different media used, basal minimal medium (BMM) was suitable for the HDPE degradation by strain MF12. Strain MF12 was subjected to 28S rRNA sequence analysis and identified as Aspergillus terreus MF12. HDPE degradation was carried out using combinatorial physical and chemical treatments in conjunction to biological treatment. The high level of HDPE degradation was observed in ultraviolet (UV) and KMnO₄/HCl with A. terreus MF12 treatment, i.e., FT10. The abiotic physical and chemical factors enhance the biodegradation of HDPE using A. terreus MF12.
Afficher plus [+] Moins [-]Biosorption of strontium from aqueous solution by fungus Aspergillus terreus
2012
Khani, M. H. | Pahlavanzadeh, H. | Alizadeh, K.
INTRODUCTION: The biosorption characteristics of strontium ions using fungus Aspergillus terreus were investigated. Experimental parameters affecting the biosorption process such as pH, contact time, initial metal concentration, and temperature were studied. MATHEMATICAL DESCRIPTION: Fungus A. terreus exhibited the highest strontium uptake capacity at 15°C at an initial strontium ion concentration of 876 mg L−1 and an initial pH of 9. Biosorption capacity increased from 219 to 308 mg g−1 with a decrease in temperature from 45°C to 15°C at this initial strontium concentration. The equilibrium data fitted very well to the Langmuir adsorption model in the concentration range of strontium ions and at all the temperatures studied. CONCLUSION: Evaluation of the experimental data in terms of biosorption dynamics showed that the biosorption of strontium onto fungus followed the pseudo-second-order dynamics well (R2 > 0.985). The calculated thermodynamics parameters (−1.64 < ∆G° < −1.93 kJ mol−1 at temperatures of 45–15°C, ∆H° = −4.83 kJ mol−1 and ∆S° = −0.01 kJ mol−1 K−1) showed that the biosorption of strontium ions were feasible, spontaneous, and exothermic at the temperature ranges of 15–45°C.
Afficher plus [+] Moins [-]Azolla pinnata, Aspergillus terreus, and Eisenia fetida for fasterrecycling of nutrients from wheat straw
2019
Arora, Manveen | Arawindara Kaura,
A vast amount of surplus wheat straw/stubble (a carbon-rich bioresource) is wasted every year by burning. Harmful gases and residue matter released due to burning cause harmful effects on the environment and human health. Therefore, there is a strong need to recycle this bioresource in a sustainable manner. In the present study, wheat straw (W) was spiked with cattle dung (C), Azolla pinnata (A), and Aspergillus terreus (F) to make eight different treatments (1 kg each), viz. W (1 kg), WC (666 g + 334 g), WA (980 g + 20 g), WF (980 g + 20 ml), WCF (666 g + 314 g + 20 ml), WCA (666 g + 314 g + 20 g), WFA (960 g+ 20 ml + 20 g), and WCFA(666 g + 294 g + 20 ml + 20 g), and subjected to vermicomposting (Vcom) and aerobic composting (Acom). A comparison was made for the time required for degradation and nutrient profile of the products. The fastest recycling of wheat straw/stubble (120 days) was observed in WCA and WCFA, but the nutrient quality of WCA was better (N 18.67, P 3.88, K 38.84 g/kg). In the Acom group, longer time was required for degradation of various mixtures, but in this group also, WCA was degraded first of all (138 days) and yielded a product with the best nutrient quality (N 14.77, P 2.56, K 28.80 g/kg). Maximum growth of E. fetida and maximum number of hatchlings were observed in WCA while the highest cocoon production was observed in WCFA. It was observed that azolla enhanced conversion of wheat straw into a nutrient-rich product for agronomic use. Thus its use will reduce the amount of cattle dung in the mixture and the bulk to be handled by the farmers for ecosafe disposal of surplus straw/stubble. Therefore, this technology can be adopted as an alternative to burning.
Afficher plus [+] Moins [-]Assessment of relevant fungal species in clinical solid wastes
2016
Noman, Efaq Ali | Al-Gheethi, AA | Norulaini Nik Ab. Rahman, | Nagao, H | Ab. Kadir, MO
The study aimed to determine the fungal diversity in clinical waste samples from a healthcare facility in Penang Malaysia. Different fungi species were detected in 83.75 % of the 92 clinical waste samples that were screened from different sections of the healthcare facility. One hundred fifty fungal isolates comprising of 8 genera and 36 species were obtained. They were purified by using single spore isolation technique. Subsequently, the isolates were identified by phenotypic method based on morphological and culture characteristics on different culture media. Among all fungal isolates, Aspergillus spp. in section Nigri 10.2 %, Aspergillus niger 9.5 %, Aspergillus fumigatus 8.8 %, Penicillium. simplicissium 8 %, Aspergillus tubingensis 7.3 %, Aspergillus terreus var. terreus 6.6 %, Penicillium waksmanii 5.9 % and Curvularia lunata 6.5 % were the most frequent. Among five sections of the Wellness Centre, the clinical wastes collected from the diagnostic labs of haematology section had the highest numbers of fungal species (29 species). Glove wastes had the highest numbers of fungal species (19 species) among 17 types of clinical wastes screened. Among all fungal species, Aspergillus spp. exhibited higher growth at 37 °C than at 28 °C, indicating the potential of these opportunistic fungi to cause diseases in human. These results indicated the potential of hospital wastes as reservoirs for fungal species.
Afficher plus [+] Moins [-]Biodegradation of pesticides using fungi species found in the aquatic environment
2015
Oliveira, B. R. | Penetra, A. | Cardoso, V. V. | Benoliel, M. J. | Barreto Crespo, M. T. | Samson, R. A. | Pereira, V. J.
Relatively limited attention has been given to the presence of fungi in the aquatic environment compared to their occurrence in other matrices. Taking advantage and recognizing the biodegradable capabilities of fungi is important, since these organisms may produce many potent enzymes capable of degrading toxic pollutants. Therefore, the aim of this study was to evaluate the potential ability of some species of filamentous fungi that occur in the aquatic environment to degrade pesticides in untreated surface water. Several laboratory-scale experiments were performed using the natural microbial population present in the aquatic environment as well as spiked fungi isolates that were found to occur in different water matrices, to test the ability of fungi to degrade several pesticides of current concern (atrazine, diuron, isoproturon and chlorfenvinphos). The results obtained in this study showed that, when spiked in sterile natural water, fungi were able to degrade chlorfenvinphos to levels below detection and unable to degrade atrazine, diuron and isoproturon. Penicillium citrinum, Aspergillus fumigatus, Aspergillus terreus and Trichoderma harzianum were found to be able to resist and degrade chlorfenvinphos. These fungi are therefore expected to play an important role in the degradation of this and other pollutants present in the aquatic environment.
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