Cristian Felix BLIDAR, Renata Ștefania GLIGOR, Ioana Maria TRIPON, Ludovic GILĂU, Sanda Rodica BOTA, Sorin HODIȘAN, Oana Delia STĂNĂȘEL

Abstract. The Nymphaea lotus L. var. thermalis (DC) Tuzson or thermal waterlily a thermophilic species is threatened with extinction due to the loss of thermal water in its natural habitat, namely the Lake “Ochiul Mare” of the “Peţea Creek” Natural Reserve. The taxon is related to the well-known species the Egyptian Nymphea lotus, but due to it long history of specific physiological and anatomical peculiarities it is considered as native for Romania. The overexploitation of thermal water in the past 30 years led to the cessation of its artesian flow inside the species habitat, causing the drying of the lake and implicitly the disappearance of this characteristic thermal ecosystem that is unique in Europe. Under these circumstances, the scope was to identify specimens of thermal waterlily that were spontaneously propagated in nature, outside the native range area. Based on the field research it was possible to determine and identify thermal waterlily specimens naturally spread, adapted and survived in the Hidişel creek bed, in a previously unreported area, thus occupying a new habitat that provides the species with conditions similar to those of the natural ecosystem. Thus, the occurrence of the thermal waterlily outside the reserve is a certainty, but not the survival of the species because in the new habitat it is subjected to a strong anthropogenic impact, being outside the protection area. Following the research performed both on the trail of the Peţea creek and on that of the Hidişel creek, the main tributary and water supplier of Peţea, approximately 166 stalks of N. l var. thermalis were identified. Although the trend of the thermal waterlily population that grow spontaneously outside its natural area is increasing apparently, the future of this species remains uncertain. Thus, the need for protection and rescue from extinction is a must and new in situ and ex situ conservation measures should be in place for the near future.




Oksana BILOKONSKA, Serhii KOZAR

Abstract. One of the tasks of modern biotechnology is the development of highly efficient inoculants based on beneficial soil bacteria that are capable of producing high stable yields. The bioagents of such inoculants may be soil diazotrophs, which play an important role in agrocenoses by fixing atmospheric nitrogen and transforming the latter into a plant-accessible form. The objective of our work was to study the viability and functional activity of Azotobacter chroococcum IMB B-7836 and to assess its effect on cucumber plants, namely on the nitrogen-fixing activity in the root zone of the plant and yield. It was found that three months after treatment, the number of bacterial cells on the seeds stored at 4 °C was significantly higher than in the variant with the storage of seeds at 28 °C. A significant negative effect of UV exposure on the viability of A. chroococcum IMB B-7836 was established. To reduce the negative effects of UV exposure during bacterization, cells of azotobacter in the form of cysts were used, which ensured the prolongation of the viability of microbial cells on the seeds until sowing in the soil. It was found that nitrogen-fixing activity in the root zone of cultivaitng cucumbers is higher with A. chroococcum IMB B-7836 in the form of cysts as compared with vegetative cells of Azobacter. Bacterization contributed to the increased productivity of cucumber plants that is more likely associated with improved nitrogen nutrition of this culture; at the same time, the highest cucumber yield was reported for pre-sowing treatment of seeds with Azobacter in the form of cysts. These findings may be applied to improve efficacy of seed bacterization affected by unfavourable environmental factors, in particular temperature and UV.

Keywords: Azotobacter chroococcum; cysts; temperature; UV exposure; viability.




Galina NAYDENOVA, Tatyana BOZHANSKA

Abstract. The study was conducted in the period 2017-2019, in the foothills of Central Northern Bulgaria, on three types of grasslands - Chrysopogon gryllus meadow, Genista-pseudo sheep's fescue (Festuca ovina - Festuca valesiaca) pasture and Bermuda grass-ryegrass (Cynodon dactylon - Lolium perenne) pasture, typical of meadows and pastures in Bulgaria. The relative share of clover species in grassland was assessed at different altitudes (134 m, 385 m and 456 m above sea level), and the chemical composition of dry fodder matter was analyzed. A total of 14 species of genus Trifolium were identified in the most common types of meadows and pastures in the Central Northern Bulgaria. The mountain and plain grasslands have specific dominant clover, which is associated by the different physiological, morphological and biological profiles of the identified species. For the mountainous region these were T. pannonicum, T. medium and T. incarnatum, and for the plain - T. echinatum, T. campestre. Species diversity and relative share are more related to the use of grasslands and edaphic factors than to climatic ones. It is important to note that the biodiversity inherent in genus Trifolium in terms of the life cycle of the species, as well as in terms of reproduction system, is equally represented in the different types of grasslands. The high natural distribution, high protein and balanced fiber and macromineral content of T. incarnatum in the mountain meadow and T. echinatum in the plain pasture, suggests the potential for inclusion of these species by resowing in the functional group of legumes in different types of grasslands.

Keywords: Trifolium spp.; clovers, biodiversity; forage quality.




Bernat TOMPA, Kristof JAKAB, Laszlo FODORPATAKI

Abstract. Efficiency of bioremediation of polluted aquatic environments with the use of microalgae can be substantially increased if tolerance of algae to stress factors is enhanced with application of very small concentrations of natural bioactive compounds. Such a substance, with a yet unknown action mechanism, but already used to improve crop quality and quantity under adverse growth conditions, is triacontanol (TRIA), a wax constituent of the plant cuticle. The present study investigates the benefic influence of 5 µM TRIA on growth and photosynthetic performance of the Tetradesmus obliquus green microalga (a test organism for bioindication of water quality) exposed for one week to the adverse influence of 50 µM cadmium chloride in the nutrient medium of axenic cell cultures. Results reveal that inhibitory influences of Cd on cell divisions, biomass production, photosynthetic pigment content and photochemical performance of photosynthesis are efficiently alleviated by TRIA. Thus, TRIA can be used to achieve a higher cell density and an enhanced stress tolerance of algal populations, in order to optimize biological purification of aquatic habitats polluted with Cd.

Keywords: bioactive plant metabolite; heavy metal stress; photosynthetic performance; Tetradesmus obliquus




Yuliia VOROBEI, Oleh DERIABIN, Tetiana USMANOVA

Abstract. Тhe new PGPR strain of genus Azospirillum, capable of fixing atmospheric nitrogen, has been isolated from the roots of spring wheat. Phenotypic features were studied and molecular genetic analysis of the new Azospirillum brasilense strain was carried out. It has been shown that inoculation of seeds of spring wheat by strain A. brasilense 137 promotes active colonization the root surface by this bacteria and increased nitrogen activity in the root zone of this culture.

Keywords: Azospirillum brasilense; physiological and biochemical properties; molecular genetic studies; spring wheat.  




Mariia LOBODA, Lyudmyla BILIAVSKA, Galyna IUTYNSKA

Abstract. Soil streptomycetes are active producers of a wide range of metabolites. In a complex of biologically active substances synthesized by Streptomyces netropsis IMV Ac-5025 polyene antibiotics and phytohormones were detected. At present, the secondary metabolites' influence on the polyene antibiotics biosynthesis by soil streptomycetes is insufficiently explored. The aim of the work was to research the effect of exogenous auxin indole-3-carbinol on polyene antibiotics and phytohormones biosynthesis by S. netropsis IMB Ac-5025. The strain was cultivated in organic and synthetic liquid nutrient media; biomass accumulation, biosynthesis of polyene antibiotics, auxins and cytokinins were determined under the action of exogenous indole-3- carbinol.
It has been found the concentration of exogenous auxin by which quantity of polyene antibiotics was increased in 2.8 and 1.9 times, auxins – in 2.9 and 2.0 times, cytokinins – in 2.8 and 5.6 times respectively. Thus, exogenous indole-3-carbinol enhanced polyenes antibiotics and phytohormones biosynthesis by S. netropsis IMV Ac-5025. This indicates an important relationship between the biosynthesis of secondary metabolites by soil streptomycetes. The possibility to regulate the amount of biologically active substances opens opportunities for elaboration of bioproduct with protective and plant stimulating properties.

Keywords: Streptomyces netropsis; indole-3-carbinol; polyene antibiotic; phytohormone.




Lamia BOUTABIA, Salah TELAILIA, Faouzi GUENADIL, Azzedine CHEFROUR

Abstract. Mentha pulegium L. and M. suaveolens Ehrh. are spontaneous plants growing in the wetlands of the Souarekh region (north-eastern Algeria). They are very well known and used by the natives of this region for different virtues. Moreover, these subspecies have been chosen for their great morphological variations. Hence, in this study, we aim at determining the chemical composition of the essential oils of both plants and evaluating their antibacterial activities. The aerial parts of the plants were hydrodistilled using a Clevenger type apparatus and the essential oils were analyzed and identified using gas chromatography-mass spectrometry. Antibacterial screening of essential oils was carried out on the basis of the diameter of the inhibition zone using the disc diffusion method against two bacterial strains. The chemical analysis of the essential oils of both mints resulted in main compounds pulegone (61.24%), isomenthone (11.32%) and menthone (5.6%) for M. pulegium, and piperityone oxide (47.52%) for M. suaveolens. Accordingly, the study of the biological activity of essential oils manifested the antibacterial effect against the strains studied. The obtained results are therefore promising and thus pave the way for manufacturers to use the essential oils of the two plants in the pharmaceutical and food industries.

Keywords: Essential oils; Mentha pulegium L.; Mentha suaveolens Ehrh.; Chemical composition; Antibacterial activity; Algeria.




Asme BOUHOUIA, Mohammed Chérif MAAZI, Azzedine CHEFROUR

Abstract. Artemisia herba-alba Asso (Asteraceae) essential oil from Fedj el dib region (Souk Ahras, Algeria) was obtained by hydro-distillation of aerial parts (stems, leaves and flowers) and analyzed by gas chromatography-mass spectrometry (GC/MS) to determine its chemical composition. The main compounds obtained are: 5,6-Dicarbadecaborane (68,33%), 1,5,5-Trimethyl-6- methylene-cyclohexene (7.00%), 4,8,12-Tetradecatrien-1-ol, 5,9,13-trimethyle (5.13%), Bicyclo-[3.1.1]heptane-2-methanol (4.39%) and Cyclo-pentane carboxylic acid 3-methylene (4.19%), Artemisia essential oil also contains Phenol, 2,3,5-trimethyl-(3.15%), Phosphoric acid tribornyl ester (0.61%) and beta.-Pinene (0.29%) and the Thujone (0.16%). Further to the analytic study of essential oil, a biological study was carried out; the purpose of this biological study was to assess the antibacterial properties of Artemisia herba-alba Asso essential oil against fourteen Gram-positive and Gram-negative bacterial strains using disk diffusion method. The results obtained reveal that the Artemisia herba alba Asso essential oil exerts a strong antimicrobial activity against all tested pathogenic bacteria except P. aeruginosa and Proteus vulgaris which were resistant even to the highest concentration of essential oil.

Keywords: essential oil; Artemisia herba-alba Asso; hydro-distillation; GC/MS; antibacterial activity.




Nour Eddine TAMMA, Abdelkarim REBIAI, Naima BENCHIKHA, Abdelkader HIMA

Abstract. The present study is quantitative in nature where the researcher highlighted the importance of quality of effective active compounds (polyphenols) that are present in palm pollen, which, plays an effective role in the treatment of many diseases. In this study, we were able to identify these compounds by detection and extraction. We quantify the phenolic compounds using the device UV-Visible. The results revealed that the total amount of phenolic compounds were higher in the phenolic extract of the Oued El Alanda region estimated at (494.496 mgEAG/g), wheres total flavonoids were higher in the phenolic extract of the Hamraia region estimated at (229.59 mgER /g). In the next step, we quantified and qualitatively estimated using the HPLC device, found that the phenolic extracts contained most of the reference phenolic compounds in varying proportions. Then the antioxidant efficacy has also been tested for phenolic compounds by the cyclic voltammetry technique, The highest total antioxidant effect was estimated in the extract of the region Hamraia (6.92 mgEAG/g). Finally, we performed another test on the antibacterial efficacy of these extracts in three types of bacteria. However, the result was positive only in one type of bacteria, known as the bacteria Listeria monocytogenes ATCC 19115, where we recorded a very effective inhibitory potency with Oued El Alanda extract estimated at 18 mm a maximum concentration that is greater than the inhibitory diameters in industrial antibiotic (Amoxicillin, Ampicillin).

Keywords: Palm pollen; active compounds (polyphenols); biological efficacy.




Okba SELAMA, Khelil SIFI, Anis Sofiane DJABROUHOU, Abdelghani ANAD, Ahmed ABDERRAHMANI, Elizabeth M.H. WELLINGTON, Hocine HACENE

Abstract. Extreme environments harbor such unusual bacterial groups that distinguish form normal ones with noteworthy bioactive molecules. The aim of this study was the isolation of UV-tolerant Actinobacteria and spore-forming bacteria strains with antimicrobial activity from the Algerian Sahara desert. Three soils were used in this study, two of which were from the Algerian Sahara desert (Melghir and Taghit) and one from an agriculture field within the university field (Algiers). Suspension/dilution on agar media followed by 15 min of UVC exposure were applied as protocol in this work. From all the irradiated plates, 46 colonies were best retrieved from both the two Algerian Sahara desert soils while less (24 colonies) from the university soil. In total, 29 distinct colonies were selected and analyzed for their macro- and micro-morphology and antimicrobial activities from which 10 strains were distinguished as UV-tolerant Actinobacteria and spore-forming bacteria with at least an antimicrobial activity against one test-microorganism. These isolates were also subject to enzymatic screening for amylase, caseinase, and lecithinase using culture dependent methods and for the presence of genes coding for putative antifungal compounds using a polymerase chain reaction (PCR) based method. In this study, we report the presence of a potential strain GT11 from the genus Bacillus with a particular activity against the pathogen fungus Fusarium oxysporum f. sp. albedinis. In addition to their UV-tolerant character, the presence of genes coding for putative antifungal compounds, combined with the antimicrobial activity against a broad range of indicator strains and their enzymatic potential, this would make these bacteria stains suitable for sustainable biotechnology applications.

Keywords: UVC; Fusarium oxysporum f. sp. albedinis; Staphylococcus aureus MRSA; Fengycin.




Amel HEROUINI, Abdellah KEMASSI, Zakaria TAIBAOUI, Ahmed AITOUDIA, Rekia CHERIF, Mohamed Didi OULD EL HADJ

Abstract. Citrullus colocynthis Schrad. (Cucrubitaceae) seed oil extract insecticidal activity was evaluated by direct spraying method on adults of Tribolium castaneum Herbst (Coleoptera: Tenebrionidae). Citrullus colocynthis was collected from Oued Larneb which is located in the Algerian Septentrional Sahara. The results showed notable mortality rates that varied from 28.89% to100% and varied considerably depending on the applied dose and the duration of exposure. The lethal effect of this oil was comparable to that of the insecticide Decis® 50EC. The estimation of the lethal doses 50 and 90 allowed us to verify the toxicity of this oil which were of the order of 0.002 mL and 0.030 mL respectively after 18 hours of observation.

Keywords: Seed oil; Citrullus colocynthis; Tribolium castaneum; insecticide; lethal dose; Algerian Sahara




Toochukwu Ekwutosi OGBULIE, Chioma Chiemezie OKORE, Agunna Everest EJELE, Ikechukwu Adiele OKWUJIAKO

Abstract. This study ascertained the comparative effectiveness of three screening assays, β hemolysis, emulsification index (E24) and oil displacement as a preliminary screening test to identify biosurfactant producing bacterial isolates. Evidently, 52 bacterial species were isolated from environmental samples and 29 of them (56%) screened negative using β hemolysis whereas 23 (44%) were positive. The emulsification index and oil displacement were carried out on 4 hydrocarbons (kerosene, crude oil, petrol, diesel) and power vegetable oil. Most of the 52 bacterial isolates emulsified and displaced the test hydrocarbons and power vegetable oil to varying levels. The E24 showed that out of the 29 hemolytic negative bacteria, 18 (62.1%) emulsified kerosene; 8 (27.6%) emulsified crude oil, 13 (44.8%) emulsified vegetable oil; 22 (75.9%) emulsified petrol and 10 (34.5%) emulsified diesel. Furthermore 69% had emulsification index above 45% indicating the test isolates as potentially suitable for microbially enhanced oil recovery [MEOR]. The oil displacement results equally showed that 15 (51.7%) displaced kerosene, 22 (75.9%) displaced crude oil; 16 (55.2%) displaced vegetable oil and 15 (51.7%) displaced both petrol and diesel respectively. This study showed that comparatively, petrol and crude oil were emulsified and displaced respectively by the bacteria isolates more than other oil sources; hence it is evident that the type of hydrocarbon affects the E24. Consequently, E24 and oil displacement are recommended to be the preliminary screening tests for identification of biosurfactant producing bacteria as the lyses of red blood cells in β hemolysis by the bacteria might be affected by some inherent factors.

Keywords: Bio-surfactant; β hemolysis; emulsification index; hydrocarbons; oil displacement.




Yeşim KAPTANBAŞ, Esra KOÇ

Abstract. This study aimed to explain the effects of different concentrations of calcium (0, 40, 80 and 120 ppm Ca), which showed an antagonistic effect on toxic levels of boron (0, 15, 30 and 45 ppm B), on growth and soluble carbohydrate levels in the seedlings of Triticum durum Desf. cv Kızıltan-91, which was sensitive to B toxicity, and Triticum aestivum L. cv Gün-91, which was tolerant to B toxicity. Compared to the control, all B concentrations treated alone caused a decrease in root length in Gün-91, all of them except for B45 resulted in increased root length in Kızıltan-91and B30 and B45 treatments reduced shoot length and shoot fresh weight in both cultivars. The longest shoot length was determined in Ca80 treatment in both cultivars. Among the B+Ca treatments, B15 + Ca120 and B45 + Ca120 increased shoot length in Gün-91, while B30 + Ca80 treatment increased shoot length in Kızıltan-91 when compared to all B concentrations treated alone. In both cultivars, the highest root fresh weight was found in Gün-91 treated with B15 + Ca120. B45 treatment decreased shoot dry weight and relative water content (RWC) in both cultivars and root dry weight in Kızıltan-91. The inhibitory effect of 45 ppm B on RWC was reduced by the presence of Ca in both cultivars. Compared to all B treatments, B45 + Ca40 was determined as the common treatment that increases RWC in both cultivars. The highest RWC value was determined in Ca40 treatment in Kızıltan-91. The lowest glucose level was determined in the B45 treatment in Gün-91 when compared to the control, and the same treatment led to decreased fructose amounts in both cultivars. The toxic effect on glucose of 30 and 45 ppm B was observed to be alleviated by calcium application, particularly at 120 ppm in both cultivars. Compared to all B treatments, B30 + Ca120 was determined as the common treatment that increases both glucose and fructose amounts in both cultivars. Findings show that the treatment of appropriate Ca concentrations might be useful in reducing B toxicity.

Keywords: boron toxicity; calcium; glucose; fructose; wheat cultivars.




Svetlana DJUR

Abstract. The article deals with the effects of inorganic germanium-containing compounds GeO2 and GeSe2 with concentrations in the range of 10-30 mg/L on Arthrospira platensis CNMN-CB-11 (spirulina) productivity, and some valuable components (proteins, phycobiliproteins, lipids and carbohydrates). In addition, germanium accumulation in cyanobacterial biomass was investigated. Data on thiobarbituric acid test showed that inorganic compounds of germanium in the range of tested concentrations did not exert high toxicity to cyanobacterium Arthrospira platensis CNMN-CB -11. This study of optimal concentration range revealed, for instance, that addition of 20 mg/L GeO2 and 10-20 mg/L of GeSe2 induces production of spirulina biomass enriched with germanium and bioactive compounds.

Keywords: Arthrospira platensis; germanium-containing compounds; productivity; bioactive substances.




Yamina BOUATROUS, Sara MECHAALA

Abstract: The objective of our work is to highlight the antibacterial activity of the different extracts of Artemisia herba-alba: oil, ethanolic and aqueous extracts, this plant was harvested in the region of El Kantra wilaya of Biskra, and the use of their oil in the process of bioconservation of raw cow's milk. The highest extraction yield was found in ethanol extract with a value of 15.64%. Thus, the quantitative study showed a richness of polyphenol and flavonoid extracts, particularly ethanol extract. On the other hand, the aromatogram and liquid dilutions methods show a strong antibacterial activity of the various extracts against S. aureus, E. coli and Salmonella sp. bacteria, while P. aeruginosa has proved resistant. The results of microbiological analyses carried out on the milk reveal the effectiveness of the oil against psychrotrophic bacteria, which reduces the quality of the milk and leads to the appearance of serious defects, particularly flavors, which make the products unsafe to eat.

Keywords: Artemisia herba-alba; antibacterial activity; bioconservation; milk.




Ahmed BOULAL, Slimane KALLOUM, Halima BEKOUCHE, Khedidja BOULAHYA

Abstract. Due to the lack of adequate wastewater treatment plant in Adrar, a city located in the southwestern part of Algeria, sewage waters are discharged directly into rivers. As part of the surveillance program for waterborne diseases (cholera, typhoid, hepatitis, parasitosis), and in order to assess the damage that may be caused, a study was carried out on the biological treatment with Moringa oleifera seeds of a few bacterial genera. Total microorganisms, total coliforms, fecal coliforms, Staphylococcus aureus, Streptococcus ssp and Clostridium ssp, at the collecting stations of domestic and industrial wastewater in the city of Adrar. The results obtained confirmed that the Moringa oleifera seeds have a positive effect on the reduction of pathogenic microorganisms encountered in wastewater. In fact, it was found that for 5 g of Moringa oleifera seed powder, and for a 60-minute contact time, the concentration of total aerobic mesophilic microorganisms in wastewater passed from 14.65*108 UFC / 100mL to 190*106UFC / 100mL. For the same operating conditions (5g and 60 min), it turned out that the reduction of pathogenic bacteria in wastewater, using Moringa oleifera seeds, was more obvious for the genus Clostridium, since these microorganisms were totally eliminated. Regarding the total coliforms, it was found that the reduction percentage was 82.5%. Still under the same operating conditions (5 g and 60 min), the reduction rates found for fecal coliforms, Staphylococcus aureus and Streptococus ssp were 81.33%, 88.23% and 89.18%, respectively.

Keywords: wastewater; Moringa oleifera; pathogenic microorganisms; seeds; reduction rate.




Zineb LOUAIL, Nadjette DJEMOUA, Soumia KRIMATE, Karima BOUTI, Sabah BOUTI, Hassina TOUNSI, Abdelkrim KAMELI

Abstract. This study describes the chemical composition, the antimicrobial and antioxidant activities of the aqueous and ethanolic extracts as well as the essential oil obtained from the fruits of the Algerian endemic subspecies Ammodaucus leucotrichus subsp. leucotrichus Cosson & Durieu. The analyzed aqueous and ethanolic extracts by HPLC technique showed the presence of ferulic acid. The most important phenolic content was observed in the ethanolic extract with 146.18±5.82 mg GAE/g DW compared to the aqueous extract with 77.51±2.21 mg GAE/g DW. The same results were obtained for flavonoids where the ethanolic extract showed a significant amount of 43.55±2.46 mg QE/g DW. The results of DPPH assay showed IC50 values of 20.64±0.52 mg/mL for the essential oil, 337.6±16.73 µg/mL for the aqueous extract and 97.89±2.91 µg/mL for the ethanolic extract. The percent inhibition bleaching of β-carotene capacity of the essential oil (43.78±1.82) was found to be higher in comparison with the two tested extracts. The obtained results of the antimicrobial activity showed remarkable inhibition zones of the tested essential oil (5 µL/disc) against many tested microorganisms. The results suggest that A. leucotrichus subsp. leucotrichus fruits constitute a novel source of natural antioxidants and antimicrobials and can continue to be used as a food additive.

Keywords: Ammodaucus leucotrichus; ethanolic and aqueous extracts; essential oil; antioxidant activity; antimicrobial activity; HPLC.




Cristina STANCĂ-MOISE

Abstract. The presence of some Lepidoptera species that are pests of forest and agricultural ecosystems hosted within the Natural History Museum of Sibiu is presented herein. They have been used in research and some have been reported and results have been published. Fourteen species belonging to six Lepidoptera families (Cossidae, Lasiocampidae, Pieridae, Notodontidae, Noctuidae, and Erebidae) have been identified. Each species is presented with information about their geographic range, damage, and plants they affect, including the type of damage produced, as well as the number of specimens identified in the six studied collections (Daniel Czekelius, Eugen Worell, Viktor Weindel, Heinrich Hann von Hannenheim, Rolf Weyrauch, and Eckbert Schneider) within the Natural History Museum in Sibiu. The data presented have a historical value and show the relevance of the species that have been collected in the region for over 117 years. They are still present in the agricultural and forest ecosystems producing significant damages to several crops.

Keywords: Lepidoptera; ecosystems; collections; type of damage; species affected.