scholarly journals Isolation and Identification of Biosurfactant Producing Bacterial Strain from Saline Soil Samples in Iran; Evaluation of Factors on Biosurfactant Production

Author(s):  
Marzieh Sajadi Bami ◽  
Payam Khazaeli ◽  
Hamid Forootanfar ◽  
Gholamreza Dehghannoudeh ◽  
Mandana Ohadi

Background: Biosurfactants are a group of valuable amphiphilic molecules that have been widely used in different industries such as pharmaceuticals and cosmetics. Objectives: The current study aimed to screen and identify a bacterial strain able to produce biosurfactant from environmental soil samples, followed by evaluating factors that contribute to biosurfactant production. Methods: The biosurfactants production was evaluated every 24 hours by emulsification index (EI), oil spreading ability, and surface tension measurement. Thereafter, the sequences of 16S rDNA genes and biochemical tests were performed to identify the isolated bacterial. Furthermore, the effect of different factors, including nitrogen, vegetable oil, and cations on biosurfactant productivity of the selected bacterial strain, was also evaluated. Results: In primary screening, out of the six bacterial strains, only one isolate was found to produce a hemolytic zone on the blood agar plate. The EI index was increased in a time-dependent manner with a maximum EI of 10% after 12h. Surface tension measurement revealed decreased surface tension (51 mN/m) after 12 hours' incubation compared to that of the blank sample. The selected isolate was recognized as Bacillus atrophaeus by 16S rDNA gene sequencing and biochemical test. All applied factors in culture media could decrease the surface tension of culture broth compared to that of the blank sample. Conclusions: This study demonstrated a Bacillus strain able to produce biosurfactants. Such biosurfactant producers would have great potentials in bioremediation activities and microbial enhanced oil recovery.

Author(s):  
Touseef Hussain ◽  
Abrar Ahmad Khan

Routine washing, cleaning, repairing, maintenance of cars, bikes, scooters and disposal of waste of all kinds are carried out in automobile workshops are common observations in Aligarh. Considering the likelihood of existence of biosurfactant producing organisms at hydrocarbon contaminated site, a large number of soil samples were collected and isolation was carried out. A total of ten bacterial strains ALIG (01–10) were isolated out of which only isolate АLIG01 grown on GSP agar, Maconkey agar as well as on Pseudomonas agar plates which indicated suspectedPseudomonas spp. and exhibits positive biosurfactant activity through penetration assay, oil spreading technique, beta hemolytic activity and ЕI24 (96%), positive blue plate agar plate (> 2сm), qualatitative analysis, tolerance against hydrocarbonm-xylene, and microplate assay. This isolate АLIG01 is a valuable source to investigate further for future agriculture plant pathology and industrial applications.


2021 ◽  
Vol 11 (8) ◽  
pp. 3542
Author(s):  
Ramida Krumsri ◽  
Kaori Ozaki ◽  
Toshiaki Teruya ◽  
Hisashi Kato-Noguchi

Phytotoxic substances released from plants are considered eco-friendly alternatives for controlling weeds in agricultural production. In this study, the leaves of Afzelia xylocarpa (Kurz) Craib. were investigated for biological activity, and their active substances were determined. Extracts of A. xylocarpa leaf exhibited concentration-dependent phytotoxic activity against the seedling length of Lepidium sativum L., Medicago sativa L., Phleum pratense L., and Echinochloa crus-galli (L.) P. Beauv. Bioassay-guided fractionation of the A. xylocarpa leaf extracts led to isolating and identifying two compounds: vanillic acid and trans-ferulic acid. Both compounds were applied to four model plants using different concentrations. The results showed both compounds significantly inhibited the model plants’ seedling length in a species-dependent manner (p < 0.05). The phytotoxic effects of trans-ferulic acid (IC50 = 0.42 to 2.43 mM) on the model plants were much greater than that of vanillic acid (IC50 = 0.73 to 3.17 mM) and P. pratense was the most sensitive to both compounds. In addition, the application of an equimolar (0.3 mM) mixture of vanillic acid and trans-ferulic acid showed the synergistic effects of the phytotoxic activity against the root length of P. pratense and L. sativum. These results suggest that the leaves of A. xylocarpa and its phytotoxic compounds could be used as a natural source of herbicides.


2020 ◽  
Vol 58 (10) ◽  
pp. 1759-1767
Author(s):  
Mieke Steenbeke ◽  
Sander De Bruyne ◽  
Jerina Boelens ◽  
Matthijs Oyaert ◽  
Griet Glorieux ◽  
...  

AbstractObjectivesIn this study, the possibilities of Fourier-transformed infrared spectroscopy (FTIR) for analysis of urine sediments and for detection of bacteria causing urinary tract infections (UTIs) were investigated.MethodsDried urine specimens of control subjects and patients presenting with various nephrological and urological conditions were analysed using mid-infrared spectroscopy (4,000–400 cm−1). Urine samples from patients with a UTI were inoculated on a blood agar plate. After drying of the pure bacterial colonies, FTIR was applied and compared with the results obtained by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). Chemometric data analysis was used to classify the different species.ResultsDue to the typical molecular assignments of lipids, proteins, nucleic acids and carbohydrates, FTIR was able to identify bacteria and showed promising results in the detection of proteins, lipids, white and red blood cells, as well as in the identification of crystals. Principal component analysis (PCA) allowed to differentiate between Gram-negative and Gram-positive species and soft independent modelling of class analogy (SIMCA) revealed promising classification ratios between the different pathogens.ConclusionsFTIR can be considered as a supplementary method for urine sediment examination and for detection of pathogenic bacteria in UTI.


2013 ◽  
Vol 726-731 ◽  
pp. 4427-4430
Author(s):  
Guo Hua Chen

Konjac soft rot is a bottleneck limiting konjac yield caused by bacterial strain of Erwinia carotovora var. carotovora. In order to control konjac soft rot, soil samples were collected, and each sample was spread on surface of a plate seeded with E. carotovora var. carotovora in advance. Strains expressing antagonistic activities were selected and then isolated with streak plate method. One bacterial strain (named Z10) was obtained from soil by this method. In field trials, strain Z10 still showed antagonistic effect against the bacterial pathogen.


1950 ◽  
Vol 40 (1-2) ◽  
pp. 150-156 ◽  
Author(s):  
F. L. M. Dawson

The genitalia of a control series of nineteen animals, slaughtered for other reasons than reproductive failure, were studied. Of these six were in various stages of pregnancy, one was in a ‘proliferative phase’, being slaughtered probably just before the first oestrus after calving, and twelve represented different phases of the oestrous cycle, more than half exemplifying the last 4 days before heat. Stages were judged from the appearance of the ovaries, and checked in five instances by repeated rectal examinations, and observation of behaviour during life. Of the nineteen uteri eight yielded bacteria on culture, sometimes in moderately high density; from two of them, pure cultures were recovered respectively of Pseudomonas and Neisseria catarrhalis; and in another, probably Proteus was found. No previous records of these three genera at such a site have been found. Only aerobic blood agar plate cultures, and those for tuberculosis organisms were made. Dissection results unequivocally supported the view of Tagliavini in opposition to that taken by Hammond, that the sanguineous elements in post-oestral discharge originated from endometrial extravasation. The cow slaughtered 4 days after heat indicated that congestion disappears from the caruncles before leaving the areas between them. Microscopically, no mast cells, as observed by the Italian workers, could be seen; it appeared that a ‘proliferative phase’ occurs in every cycle during the three pre-oestral days, when gland tissue proliferates from its nadir of development, surface epithelium grows in height, and vascularization progresses. The rate and interrelations of these changes seemed variable. Arterioles appeared to be withdrawn from the superficial mucosa during the secretory phase. Tagliavini's claim to have observed sloughing of epithelium about the 17th day, strictly equivalent to the process of menstruation in the Primates, must on the evidence be regarded with considerable reserve.


Author(s):  
L.A. Maldonado ◽  
M.E. Hamid ◽  
O.A. Gamal El Din ◽  
M. Goodfellow

Fifteen of 100 mastitic milk samples from goats suffering from mastitis were tentatively identified as members of the genus Nocardia on the basis of selected phenotypic and chemotaxonomic characteristics. Six of the 15 strains were confirmed as Nocardia farcinica by 16S rDNA gene sequencing and subsequent aligning with relevant actinomycetes found in electronic databases and 2 by other identification criteria. N. farcinica is a serious cause of mastitis with a significant prevalence (15%) among the examined goats. Efforts are needed to optimise and simplify isolation and identification methods.


2010 ◽  
Vol 2010 ◽  
pp. 1-8 ◽  
Author(s):  
Gizele Cardoso Fontes ◽  
Priscilla Filomena Fonseca Amaral ◽  
Marcio Nele ◽  
Maria Alice Zarur Coelho

In order to improve biosurfactant production byYarrowia lipolyticaIMUFRJ 50682, a factorial design was carried out. A24full factorial design was used to investigate the effects of nitrogen sources (urea, ammonium sulfate, yeast extract, and peptone) on maximum variation of surface tension (ΔST) and emulsification index (EI). The best results (67.7% of EI and 20.9 mNm−1ofΔST) were obtained in a medium composed of 10 g 1−1of ammonium sulfate and 0.5 g 1−1of yeast extract. Then, the effects of carbon sources (glycerol, hexadecane, olive oil, and glucose) were evaluated. The most favorable medium for biosurfactant production was composed of both glucose (4% w/v) and glycerol (2% w/v), which provided an EI of 81.3% and aΔST of 19.5 mN m−1. The experimental design optimization enhancedΔEI by 110.7% andΔST by 108.1% in relation to the standard process.


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