Sabouraud Glucose Research Articles

Evaluation of microbiological purity of nasal ointment "Mnemastym"

The aim of this work was the determination of microbiological purity of nasal ointment “Mnemastym” with arginine-vasopressin (AVP). Materials and methods. For the microbial contamination control the inoculations were made on the nutrient medium set: for colibacillus – Endo agar, for staphylococcus – vitelline-saline agar and for fungi – Sabouraud's glucose agar. Petri dishes with inoculations were incubated during 48 hours at the tempereture 37 °C. Next identification was carried out by the traditional method. Results . It was determined that amount of microorganisms (bacteria and fungi) in 1 g of composition isn’t more than allowable standard by State Pharmacopoea of Ukraine for this class of dosage forms, but lies near critical value. It is sufficient for extemporaneous compounding of nasal ointment “Mnemastym” but at the same time development of further manufacturing of drug with the adding of antiseptic excipients is necessary. On the base of complex pharmaco-technological, biopharmaceutical, physical-chemical, rheological and biological investigations the optimal composition and technology for compounding of nasal ointment “Mnemastym” for the therapy of cognitive consequences of cerebrovascular pathology were developed. Conclusions . It was determined that manufacturing of nasal dosage form “Mnemastym” needs an adding of excipients with antimicrobial activity for stabilization of microbial contamination process. It was revealed that for the minimization of this standardization value for the ointment on lipophilic base in pharmacopoeia limit using of polyhexamethylenguanidin phosphate of triclozane or mixture of nipagin: nipazole 8:2 in 0.15 % concentration is the most rationale. Adding of preservatives in nasal ointment with vasopressin on lipophilic base for extemporaneous compounding isn’t need.

Prevalence of vulvovaginal candidiasis in pregnancy at three health centers in Burkina Faso

Pregnant women are more susceptible to vaginal colonization and infection by yeast. The role of Candida colonization in the occurrence of preterm birth is well established. The knowledge of local epidemiology and identification of risk factors for preterm birth is important for the prevention and management strategies. The purpose of the study was to determine the prevalence of Candidasp. in vaginal swabs of pregnant women. Pregnant women attending routine antenatal visits in three primary health centres in Bobo-Dioulasso (Burkina Faso) were enrolled into a cross-sectional study carried out from February to April 2015. Vaginal swabs samples were taken from participants after obtaining oral consent. The swabs were inoculated into Sabouraud's glucose agar supplemented with chloramphenicol and incubated at 37°C for 24 to 48hours under aerobic conditions in order to perform fungal culture. The identification of the Candida species was done by culture on HiCrome Candida Differential Agar at 35°C for 48h for production of species-specific colors. A total of 229pregnant women were included. The prevalence of vulvovaginal candidiasis (VVC) was 22.71%, (95% CI [17.45-28.69]). Candidaalbicans accounted for 40.39% and non-Candidaalbicans species for 59.61% of the isolates, with mainly C.glabrata (32.69%), C.tropicalis (15.38%) and C.krusei (11.54%). This study revealed a high prevalence of non-C.albicans species. The syndromic management guidelines for VVC in Burkina Faso will be revised to include a specific protocol for pregnant women.

Inhibition of dermatophytes by photodynamic treatment with curcumin.

Treatment of dermatophytoses with currently available antimycotic agents is often tedious and sometimes unsatisfactory. A search for better therapeutic methods-ideally with an immediate fungicidal effect-has, among others, lead to photodynamic procedures as a promising alternative, and recently curcumin was found to be a suitable agent for this application. In this study the effect of photodynamic treatment with curcumin on dermatophytes was tested in vitro. Wells of microtiter plates were filled with conidia of Trichophyton rubrum, Trichophyton interdigitale, Trichophyton terrestre, Microsporum canis, Microsporum gypseum and Epidermophyton floccosum in buffer. Then curcumin was added to the conidia and after 20min the assays were irradiated one time only with visible light (peak wave length 367nm, 5J/cm2). Thereafter the wells were filled up with Sabouraud's glucose broth and in the following fungal growth was measured photometrically. The results showed that all dermatophytes were markedly inhibited depending on the concentration of curcumin. With 5.4mg/l curcumin plus irradiation fungal growth was significantly suppressed over a period of 96h (P < .001). Even after 96h inhibition of T. rubrum was still complete and marked for all other species as well. M. gypseum was least susceptible. Our results are very encouraging to pursue the development of a photodynamic therapy of tinea with curcumin. The outstanding tolerance of curcumin and the innocuousness of the required light are favorable preconditions for this task.

Analysis of Black Fungal Biofilms Occurring at Domestic Water Taps (II): Potential Routes of Entry

Formation of tenacious and massive black biofilms was occasionally observed at the water-air interphase of water taps and in associated habitats at several locations in Germany. Exophiala lecanii-corni was proven to be the dominant component of these biofilms. Water utility companies were interested to understand by which route fungi building these black biofilms enter their habitat at affected sites in domestic sanitary. A wide variety of fungi is known to be common in wet indoor environments, as well as in the drinking water resources. Two possible routes of entry are therefore considered as follows: (a) distribution by the drinking water system or (b) a retrograde route of colonisation. Previous compositional analysis revealed that the black constituents of biofilms primarily belong to the herpotrichiellaceous black yeast and relatives. Therefore, a systematic search for black fungi in the drinking water system was performed using Sabouraud's glucose agar medium with chloramphenicol and erythritol-chloramphenicol agar as isolation media. Cadophora malorum was the dominant fungus in the investigated drinking water systems, and samples taken from the house connections (n = 50; 74 %, <200 cfu/L), followed by a so far undescribed Alternaria sp. (28 %; <10 cfu/L) and E. castellanii (26 %; <10 cfu/L). Of note, C. malorum was not present in any previously analysed biofilm. Since E. lecanii-corni was not found in any water sample from the distribution system tested, but represented the most abundant species in dark biofilms previously analysed, a retrograde route of contamination in case of E. lecanii-corni can be assumed.

First report of aCryptococcus magnusinfection in a cat

This report describes an uncommon case of cryptococcosis in an apparently immunocompetent cat caused by Cryptococcus magnus. An amputation of the complete left foreleg and excision of the ipsilateral cervical lymph node were performed in a young-adult male Domestic Shorthair cat due to suspicion of a tumor. Granulomatous dermatitis, panniculitis, myositis, and lymphadenitis were diagnosed histologically. Intralesional, numerous round-to-ovoid yeast cells showing no capsule were detected within macrophages using special staining methods. The tissue material cultured on Sabouraud's glucose agar at 26&#x00B0;C yielded abundant growth of yeast colonies. Morphological, physiological, and molecular analyses of the yeasts demonstrated that the fungus was C. magnus. Response to treatment with fluconazole was fast and effective, and one year after the end of the therapy no further clinical signs of infection were observed.

Assessment of growth-inhibiting effect of some plant essential oils on different Fusarium isolates

Essential oils (EO) of five medicinal plants were tested for anti-Fusarium activity against 10 non-toxigenic (Fusarium solani and Fusarium oxysporum) and 11 toxigenic (Fusarium verticillioides, Fusarium poae and Fusarium equiseti) isolates. Different dilutions of EO were prepared and 5 × 103 conidia of each fungal suspension were inoculated into Sabouraud's glucose broth tubes. The cultures were incubated at 28 °C for 4 days. Mean concentrations of the EO of Zataria multiflora (165.4 and 88.9 μg/ml), Cuminum cyminum (159 and 185.3 μg/ml), Foeniculum vulgare (496.4 and 532.9 μg/ml), Pinaceae (869.7 and 852.43 μg/ml) and Heracleum persicum (753.5 and 1492.6 μg/ml) completely inhibit all the non-toxigenic and toxigenic isolates, respectively. Z. multiflora and H. persicum showed the highest and lowest activity against toxigenic Fusarium isolates, whereas C. cyminum and H. persicum had the highest and lowest effect on non-toxigenic isolates, respectively. However, F. vulgare and Pinaceae had moderate effects against tested fungi. The results indicated that non-toxigenic and toxigenic Fusarium isolates were sensitive to the five EO, particularly sensitive to C. cyminum and Z. multiflora, respectively. Les huiles essentielles (essential oils [EO]) de cinq plantes médicinales ont été testées pour leur activité antifongique contre diverses souches de Fusarium: dix non toxigènes (Fusarium solani et Fusarium oxysporum) et 11 toxinogènes (Fusarium verticillioides, Fusarium poae and Fusarium equiseti). Les dilutions différentes d’EO ont été préparées et 5 × 103 conidies de chaque suspension fongique a été ensemençées dans les tubes de bouillon de glucose de Sabouraud contenant les EO. Les cultures ont été incubé à 28 °C pendant quatre jours. Les concentrations moyennes de l’EO de Zataria multiflora (165,4 et 88,9 μg/ml), Cuminum cyminum (159 et 185,3 μg/ml), Foeniculum vulgare (496,4 et 532,9 μg/ml), Pinaceae (869,7 et 852,43 μg/ml), Heracleum persicum (753,5 et 1492,6 μg/ml) inhibent complètement tous les isolats toxigènes et non toxigènes. Z. multiflora et H. persicum ont montré respectivement la plus forte et la plus faible activité contre les isolats toxigènes de Fusarium, tandis que C. cyminum et H. persicum ont eu respectivement la plus forte et la plus basse activité sur les isolats non toxigènes. Cependant, F. vulgare et Pinaceae ont eu un effet modéré contre les mycètes essayés. Les résultats ont indiqué que les isolats de Fusarium toxigènes et non toxigènes testés étaient sensibles au cinq EO, et notamment sensibles à celles de C. cyminum et de Z. multiflora.

Malassezia cuniculisp. nov., a novel yeast species isolated from rabbit skin

Members of the genus Malassezia have rarely been associated with lagomorphs. During the course of an investigation of the lipophilic mycobiota of rabbit skin, two lipid-dependent isolates which could not be identified were recovered on Leeming and Notman agar medium from different animals. No growth of Malassezia yeasts was obtained either on Sabouraud's glucose agar or modified Dixon agar media. In this study, we describe a new taxon, Malassezia cuniculi sp. nov., including its morphological and physiological characteristics. The validation of this new species was supported by analysis of the D1/D2 regions of the 26S rRNA gene and the ITS-5.8S rRNA gene sequences. The results of these studies confirm the separation of this new species from the other species of the genus Malassezia, as well as the presence of Malassezia yeasts on lagomorphs.

Nondermatophytic moulds as a causative agent of onychomycosis in Tehran

Background:In the last few years the number of cases of nondermatophytic onychomycosis has greatly increased.Aim:To evaluate the incidence, the clinic characteristics, and predisposing factors of nondermatophytic onychomycosis.Materials and Methods:All collected specimens were analyzed by direct microscopy and culture. Microscopic examination of these specimens was carried out in potassium hydroxide solution (20%) with dimethyl sulfoxide (4%). These specimens were cultured on sabouraud's glucose agar with chloramphenicol and sabouraud's glucose agar with chloramphenicol and cycloheximide. Cultures were incubated at 25°C for up to 28 days and checked twice weekly for growth.Results:Nondermatophytic onychomycosis were 11.5% of all onychomycosis. We found that Aspergillus spp. were the more responsible etiologic agents of nondermatophytic onychomycosis, resulting in a total of 28 patients (59.6%). In our study other causative agents were Acremonium spp. (17%), Fusarium spp. (12.7%), Geotrichum spp. (4.2%), Trichosporun spp., (4.2%) and Scopulariopsis spp (2.1%). In our patients moulds onychomycosis developed mainly in toenails (74.5%).Conclusion:Knowing the exact pathogen is important and has implications in therapy and prognosis.

Case of chromoblastomycosis appearing in an Okinawa patient with a medical history of Hansen's disease

Chromoblastomycosis is one of several chronic infectious skin diseases caused by various species of dematiaceous fungi. It is clinically characterized by verrucous skin eruptions and occurs most commonly in tropical and subtropical regions. In Okinawa, a subtropical area, there have been only three reported cases of chromoblastomycosis including the present one. Direct microscopic examination of crust specimens and findings of sclerotic cells in histopathology can confirm the diagnosis, and cultures of crust and/or tissue specimens can identify the causative fungi. We herein report the third case of chromoblastomycosis in Okinawa; it arose in an 87-year-old Japanese woman with a history of Hansen's disease, who lived in a leprosarium in Miyako Island. To identify the causative agent as Fonsecaea pedrosoi, we used the polymerase chain reaction and direct sequencing analysis in addition to the usual methods, which include 20% potassium hydroxide microscopy, histopathological confirmation of sclerotic cells by periodic acid-Schiff stain, culture by Sabouraud's glucose agar, slide culture method, and observation of conidia by scanning electron microscopic examination.

Evaluation of Mueller‐Hinton‐agar as a simple medium for the germ tube production of Candida albicans and Candida dubliniensis

Candida albicans is the most frequently isolated yeast species from clinical specimens. A classical rapid presumptive differentiation from non-albicans species is based on its ability to produce germ tubes after incubation in human serum. The only non-albicans Candida species producing germ tubes is Candida dubliniensis. In this study, we evaluated Mueller-Hinton-agar (MH-agar) as a medium for germ tube formation of C. albicans and C. dubliniensis. A total of 859 yeast isolates from stool samples, including 632 strains of C. albicans, 10 C. dubliniensis and 217 other yeast strains from 20 different species, were grown on Sabouraud glucose (2%) agar at 37 degrees C for 24-72 h. Species were identified by standard methods. For the germ tube test (GTT), an inoculum from a single colony was streaked onto a MH-agar plate and covered by a sterile coverslip. After incubation at 37 degrees C for 2 h, the MH plates were examined using a light microscope at x200. The GTT was positive in 578 of 632 C. albicans strains (sensitivity 91.5%), in six of 10 C. dubliniensis strains (sensitivity 60.0%), and in none of the other yeast strains. MH-agar is a suitable medium for the GTT and the presumptive identification of C. albicans. It is safer to use than human serum and is widely available in microbiology laboratories.

Comparison of hairbrush, toothbrush and cotton swab methods for diagnosing asymptomatic dermatophyte scalp carriage

Tinea capitis may also present as a minimal infection, termed carrier state. Anthropophilic dermatophytes (i.e. Trichophyton tonsurans and Trichophyton violaceum) have been generally associated with high rates of asymptomatic carriage. The aim of this study was to compare the efficacy of the hairbrush, toothbrush and cotton swab methods for diagnosing scalp carriage as well as to determine the prevalence and related dermatophyte species for both asymptomatic and symptomatic tinea capitis in Adana Province, Turkey. A screening study was carried out between February 2006 and May 2006, covering three schools and a total of 1560 children with 857 (54.9%) boys and 703 (45.1%) girls, aged between 7 and 17 years (10.6 +/- 2.3 years). The diagnosis was made by using three of the methods mentioned above with inoculation onto Sabouraud glucose agar. Symptomatic tinea capitis was not detected in the study; however, 21 (1.3%) asymptomatic carriers, with 9 (42.9%) boys and 12 (57.1%) girls, aged 7 to 13 years (9.7 +/- 1.9 years) were detected. The diagnosis was made via hairbrush in 13, via cotton swab in 4 and via toothbrush in 4. The mean age (P = 0.075) and gender differences were found to be statistically insignificant (P = 0.26). The most common isolated species was Trichophyton mentagrophytes var. mentagrophytes (90.4%) followed by Trichophyton audouinii (4.8%) and Microsporum gypseum (4.8%). Nine children had Arab origin (P = 0.005), and 12 had immigrated from the south-eastern region of Anatolia, Turkey. The screening of 32 households of 21 children with asymptomatic carriage enabled the researchers to detect the carrier state in three mothers and one sister, resulting in a total of four households (12.5%), with T. mentagrophytes var. mentagrophytes isolated, by hairbrush method in three cases and cotton swab in one case. If the methods were to be used alone, the prevalence of asymptomatic carriage would be found as 1.0% (16 of 1592) in the hairbrush, 0.3% (4 of 1592) in the toothbrush and 0.3% (5 of 1592) in the cotton swab methods; whereas the combined use of these three methods could reveal a total prevalence of 1.6% (25 of 1592). The hairbrush method was significantly found to be more effective in detecting dermatophyte fungi than the toothbrush (P < 0.01) and the cotton swab methods (P < 0.05). There was also a statistically significant difference between the use of a single method and the combination of all other three methods (P < 0.005). In summary, it was found that the prevalence of asymptomatic carriage did not cover symptomatic tinea capitis prevalence (1.6% vs. 0%), and the dominant species was zoophilic T. mentagrophytes (92%, 23 of 25). Asymptomatic carriage was not found to be related to age, gender and the coexistence of other dermatophytoses; however, race (Arab origin) was found to be the only risk factor. For laboratory diagnosis, no method was found to be nominated as a gold standard; hence, a combined use of diagnosing methods was suggested.

Keratitis Caused by a Rare Fungus, Malassezia restricta

Malassezia species rarely cause keratitis, and, thus, the clinical manifestations of Malassezia keratitis are not well known. We report the clinical findings in a 70-year-old woman who complained of pain in her left eye. Slit-lamp biomicroscopy showed a corneal ulcer with irregular infiltration, which resembled keratitis caused by filamentous fungi. KOH Parker ink stain of a corneal scraping showed mold hyphae and yeast, but cultures on Sabouraud's glucose agar plates and blood agar plates were negative. Treatment with antibacterial agents failed. Polymerase chain reaction (PCR) and DNA typing of the fungal gene between the internal transcribed spacer 2 (ITS2) and the 5.8S ribosomal DNA of the scraping were performed. PCR amplified a band with a sequence that was 99% homologous with Malassezia restricta. Antifungal agents, topical 5% pimaricin ointment and 0.2% miconazole, and oral itraconazole 150 mg/day, were applied, and the corneal ulcer disappeared within 5 weeks. Malassezia restricta can cause keratitis, and the clinical findings resemble keratitis caused by filamentous fungi. PCR and DNA typing of ITS2 and 5.8S ribosomal DNA are valuable techniques for detecting and identifying Malassezia species. Proper identification of Malassezia keratitis permits a prompt and successful treatment by antifungal agents.

Isolation of Sporothrix schenckii from the environmental sources of cutaneous sporotrichosis patients in Himachal Pradesh, India: results of a pilot study

Himachal Pradesh, India is a known endemic area for cutaneous sporotrichosis. No attempt has been made to isolate Sporothrix schenckii, the causative fungus, from environmental sources in this region or in India as such. This prospective study was carried out to isolate Sporothrix schenckii from different environmental samples collected from the vicinity of cutaneous sporotrichosis patients. All patients of cutaneous sporotrichosis diagnosed during March 2005-February 2006 were studied. Twenty-one biopsy specimens and 62 environmental samples of soil, various thorns, corn-stalk, grass-blades and sphagnum moss were subjected to mycologic culture on Sabouraud's glucose agar. Sporothrix schenckii was identified by colony characteristics, lacto-phenol cotton blue mounts and demonstration of temperature dimorphism. These patients (F : M 15 : 6) were between 12 and 72 years of age and had cutaneous lesions for 45 days to 4 years. Lymphocutaneous and fixed cutaneous sporotrichosis was seen in 14 (66.6%) and 7 (33.3%) patients respectively. Extremities were involved in 16 (76.2%); and 5 (23.8%) patients had facial lesions. Ten (47.4%) biopsy specimens and six environmental (three soil, three corn-stalk) samples were culture-positive, which showed morphological characteristics suggesting Sporothrix schenckii. No variation in colony characteristics and mycelial morphology was observed in growth isolates from clinical or environmental samples. Temperature dimorphism was observed in all the 10 isolates obtained from the clinical specimens and in two isolates cultured from corn-stalk. Corn-stalks are evidently important sources of Sporothrix schenckii infection although subsequent contamination of wounds appears more important for development of clinical disease. Culture of Sporothrix schenckii from environmental sources may not be always possible to correlate with profile of injuries.

爪白せんからの起因菌同定における培養法とＰＣＲ‐ＲＦＬＰ法の比較検討

To identify the pathogenic fungi of dermatophytosis, restriction fragment length polymorphism (RFLP) analysis of PCR amplified ribosomal DNA including internal transcribed spacers (ITS) has been established in Japan. Our purpose was to evaluate the usability of PCR-RFLP analysis to identify the causative agent of tinea unguium directly from a nail sample. Samples of tinea unguium from 100 nails were collected and cultured on Sabouraud's glucose agar and observed for 2 months. DNA was extracted from these samples, and the PCR product was digested with restriction enzymes Mva I and Hinf I. Weight of the samples was determined. Sensitivity of PCR-RFLP analysis (73%) was higher than that of culture (20%) showing that PCR is more advantageous for identification of the causative agent of tinea unguium. Sensitivity of PCR-RFLP did not depend on weight of the nail sample.

Importance of the direct fresh examination in the diagnosis of cutaneous sporotrichosis

To date the direct fresh examination has not been considered, except by a few authors, as a valid laboratory procedure for the diagnosis of cutaneous sporotrichosis. Forty-two patients with cutaneous sporotrichosis (36 lymphangitic and six fixed) were studied. Pus was obtained through digital compression of opened lesions followed by collection with a spatula and examination of the material between the slide and the coverslip. Cultures on Sabouraud's glucose agar slants with cloramphenicol and cicloheximide were made in all cases. Direct, fresh examination asteroid bodies of Sporothrix schenckii were found in 85.7% of the cases, which allowed the authors to immediately diagnose the disease. Cultures confirmed the diagnosis in 95.2% of the patients. Fastness, simplicity and low cost of the fresh examination lead us to recommend systematic use of the method for primary diagnosis of the disease, mainly at first level public health laboratories.

Otomycoses of candidal origin in eastern Slovakia

Mycological analysis of swabs and scraping samples from the external ear canals of 40 patients with clinically diagnosed otomycosis (10 neonates, 30 adults) revealed the presence of fungi as etiological agents. They were investigated microscopically using 20 % potassium hydroxide, and by cultivation on Sabouraud's glucose agar. The Candida species were identified using the germ-tube test, micromorphology observations of colonies on rice agar, and particularly by the commercial kit AUXAcolor. The following Candida species were identified in the aural material examined: C. albicans (n = 21; 52.5 %), C. parapsilosis (11; 27.5), C. tropicalis (3; 7.5), C. krusei (3; 7.5), C. guilliermondii (2; 5.0). The above yeasts were present in samples together with Staphylococcus epidermidis (31), S. aureus (16), alpha-hemolytic streptococci (14), Neisseria spp. (14), Proteus mirabilis (3), Pseudomonas aeruginosa (3), Escherichia coli (1) and Haemophilus influenzae (1). The most frequent predisposing factors for otomycosis were swimming in public pools and/or bath, spa and diabetes mellitus.

Superficial mycoses and HIV infection in Yaounde.

The incidence of superficial infections in patients with human immunodeficiency virus (HIV) is increasing in Yaounde. To determine the prevalence of superficial mycoses in HIV-positive subjects, a study was carried out in different hospital settings in Yaounde over a period of 18 months. Clinical observations were followed by the culture of samples on Sabouraud's glucose agar. Of the 148 HIVab-positive patients examined, 79 (44 males and 35 females) had at least one superficial mycosis (53%). The clinical presentations and the causative organisms did not differ from those found in immunocompetent individuals. The main lesions were oral candidiasis (77%), tinea corporis (21%), tinea versicolor (15%), tinea pedis (13%) and tinea inguium (12%). Trichophyton rubrum and Candida albicans were the organisms most commonly isolated. These results indicate the benefit of studying superficial mycoses for optimal management of HIV patients.

A simple method to identify pathogenic fungi in Sabouraud's glucose agar slant culture using fungi-tape and MycoPerm-Blue

Pathogenic fungi can be identified by growth in special culture medium, colony appearance based on microscopic examination of conidia and hyphae, and by molecular biological techniques. However, these methods are time-consuming and labor-intensive. We describe a simple method for identification of pathogenic fungi from Sabouraud's glucose agar slant culture, using Fungi-Tape and MycoPerm-Blue. It is rapid and easy, and permits visualization of fungal morphology. Using the Fungi-Tape and MycoPerm-Blue technique, we correctly identified 47 of 66 samples, for a 73.4% concordance with conventional identification methods. It is also noteworthy that slides prepared using this method can be stored for long periods without deterioration.

Oral manifestation of sporotrichosis in AIDS patients

A wide spectrum of oral lesions has been associated with human immunodeficiency viral infection (HIV), or AIDS. This report describes the case of an HIV-infected patient who developed a case of disseminated sporotrichosis whose first clinical sign was the presence of orofacial lesions. A histopathological study of this patient's biopsy specimens taken from the oropharyngeal lesions revealed a number of rounded and/or oval free-spore forms of Sporothrix schenkii, the identification of which was corroborated by culturing skin lesion exudate on Sabouraud's glucose agar. To the best of our knowledge to date, this is the first time a case of the oral manifestation of sporotrichosis in association with HIV infection has been described in the dental literature.

Microbiological profile of crude oil in storage tanks

Microbiological quality of crude oil storage tanks was determined. The samples were taken from crude oil storage tanks in three stations, at Ughelli, Escravos and Forcados tank farms in the Delta State of Nigeria. Two tanks were sampled at each station with samples collected from three levels of the tank, namely the oil layer, oil water interface, and effluent layer. Samples from the inner walls and bottom sediment of the only empty tank in Ughelli during the study were also taken. The total heterotrophic count of bacteria and total fungal count were obtained by plating samples on nutrient agar and sabouraud's glucose agar respectively and incubated for 14 days at 28 °C±2 °C. Oilutilizing bacteria and fungi were isolated on oil agar using fungizone and antibiotics to inhibit fungal and bacterial growth respectively. Pure cultures of bacteria and fungi were prepared on nutrient agar and sabouraud's glucose agar respectively at 28 °C±2 °C for 4 days. Isolates were identified using approved standard methods. Three bacterial genera, Pseudomonas, Proteus and Bacillus, and one actinomycete, Actinomyces and two fungal genera, Penicillium and Cunninghamella, were isolated. Pseudomonas was dominant among the bacteria (41.62%) and Penicillium dominant among the fungi (94%). It was also found that the total microbial load of the effluent layer was higher than that of the oil layer.