CHARACTERIZATION OF CHITINASE FROM THE AFRICAN CATFISH, CLARIAS GARIEPINUS (BURCHELL, 1822)

Chitinases are hydrolytic enzymes that break down the glycosidic bonds in chitin. The role of Chitinases in the treatment and prevention of various diseases have been reported. They have been implicated in the human health care for the treatment of fungal infections, in Asthma and in the control of mosquito which causes the deadly malaria disease accounting for about 70% of infant mortality in Africa. Chitinase was obtained from chitinolytic bacteria inhabiting the skin and gut of the African Catfish (Clarias gariepinus). Bacterial population Isolated from catfish was screened on colloidal-chitin agar medium. The ability to produce Chitinase was determined by zones of hydrolysis produced after 96h of incubation at 37oC. Isolation of chitinase was carried out with colloidal chitin as substrate in sodium phosphate buffer. Optimum conditions were therefore ascertained at a temperature of 500C and a substrate concentration of 0.15g for chitinase produced by bacteria spp (isolate code 17 and 36) while pH 5.5 was obtained for isolate code 36 and pH 6.0 for isolate code 17. The Michaelis –Mentens constant (Km) which is also known as the dissociation constant is the substrate concentration at half maximum velocity. Calculated from the Lineweaver-Burk plot, the apparent Km values for the hydrolysis of chitin by chitinolytic bacterial isolate code 36 and isolate code 17 were approximately 0.09mg/ml and 0.007mg/ml respectively. Isolation of DNA and PCR amplification carried out identified the bacteria as a member of the genus Bacillus. This study established that species of Bacillus inhabiting the gut and skin of the African catfish can be used for Chitinase production in appreciable quantity

Studies on Staphylococcus aureus Isolated from Pimples

Background and Objective: Pimples (acne) are small skin lesions or inflammations of the skin. The most common factor causing acne is the hormonal changes that occur during adolescent and teenage years. Antibiotics are becoming less effective in the treatment of pimples due to increasing concerns of antibiotic resistance. This study was therefore carried out to characterize the isolates from the pimples of Covenant University Students and to determine their antibiotics sensitivity pattern. Materials and Methods: A total of 20 swab samples were obtained from male and female students with obvious signs of pimples in Covenant University, Ota, Ogun State, Nigeria. The samples obtained were cultured on Mannitol Salt Agar and incubated at 37EC. Pure isolates obtained were subjected to Gram staining and other biochemical tests for identification. The isolates were further subjected to antibiotics sensitivity tests using antibiotic dics. Results: Macroscopic examination indicated that the organisms were convex, smooth and shiny. Microscopic examination revealed that the isolates were positive after employing the Gram Staining technique and they appeared as grape-like clusters. Biochemical tests revealed that the isolates were Coagulase positive, Catalase positive, Urease positive, Citrate positive, Methyl-Red positive, Voges-Proskauer negative and negative upon starch hydrolysis. The sugar fermentation tests revealed that the isolates fermented Glucose, Maltose, Galactose, Sucrose and Lactose, respectively. The antibiotic susceptibility test showed that isolates were resistant to Cotrimazole, Cloxacillin, Erythromycin, Gentamycin, Augmentin, Streptomycin, Tetracycline and Chloramphenicol. Conclusion: The results therefore indicated that the isolates were Staphylococcus aureus and other staphylococci species. Indiscriminate use of antibiotics should be avoided to prevent the development of resistant strains of the Staphylococci genera and other pathogenic organisms

Assessment of Microbiological Qualities and Iodine Contents of Some Brands of Domestic Salt Available in South-eastern Nigeria

Domestic salt is a food condiment, thus, a veritable tool for food contamination. Salt iodisation provides iodine an essential micronutrient and a key component of the thyroid hormones that regulate vital metabolic activities in the body. Insufficiency of iodine results in iodine deficiency disorders (IDD) which affect the functions of vital organs and systems of the body, leading to damaging effects particularly in pregnancy and early childhood, causing miscarriages, stillbirth, mental retardation, and increased infant mortality. Thirty samples of domestic salt made up of ten each of three popular brands in Nigerian markets were obtained from retail stores and evaluated for microbial qualities and iodine contents. Standard microbiological methods and iodometric titration method were employed for sample analysis. Bacillus and fungal species were isolated after sample pre-enrichment and within counts ( 30 ppm iodine at distributor and retail levels and > 50 ppm iodine at port of entry and salt factory level. This could indicate none compliance to standard specifications. There is need for effective legislation and strict monitoring of food fortification at all levels to ensure compliance to standards and adherence to good manufacturing practices/hazard analysis and quality control precepts which are imperative to effective food fortification programmes

An Overview of Enzyme Immobilization

The use of enzymes as biological catalysts has gained increasing importance in industries. Although enzymes can be obtained from plant and animal origin, microbial enzymes have several advantages over enzymes derived from other sources. Due to the high cost of separation of enzymes from product, the instability of enzymes and reduced enzyme activity, several strategies are now been explored to develop immobilized enzymes. Immobilized enzymes have been produced by cell immobilization techniques. Immobilized enzymes have found several industrial applications where they provide the advantages of easy separation of the enzyme from the product, reuse of the enzyme, convenient handling, high stability under extreme physical and chemical conditions, being applicable for all types of reactors with varied interior design, and provides easier process control. However, despite these advantages, enzyme immobilization techniques continue to pose some challenges. These challenges notwithstanding, the development of industrial by-products based on immobilization techniques is very promising

SCREENING AND PARTIAL PURIFICATION OF AMYLASE FROM ASPERGILLUS NIGER ISOLATED FROM DETERIORATED TOMATO (LYCOPERSICON ESCULENTUM MILL.) FRUITS

Amylases (EC 3.2.1.1) are cellwall degrading enzymes associated with the pathogenicity of microorganisms in the spoilage of tomato fruits. The use of amylase in many industries has made it very important to optimize production process to achieve maximum yields. Screening and partial purification of Amylase from Aspergillus niger isolated from tomato (Lycopersicon esculentum Mill.) fruits was studied. Amylase producing fungi were isolated from fresh tomatoes kept at ambient temperature (28±1˚C). Isolates were characterized on the basis of their morphological and cultural techniques. Partial purification of amylase was carried out by ammonium sulphate precipitation. The enzyme activity was determined and optimum conditions were obtained. The molecular weights of the crude and partially purified Amylase were determined by SDS PAGE method. A total of five isolates were obtained using basic screening technique for amylase activity, one of the isolates (Isolate code F2) exhibited maximum amylase activity. The fungi isolate code F2 was identified as Aspergillus niger. Optimum conditions for Amylase AMY F2 were ascertained at pH 6.0; temperature 30°C; substrate concentration of 0.3mg/ml, and time of heating of less than 10min. The molecular weights of the crude and partially purified Amylase AMY F2 were found to be 55kDa and 35kDa respectively by SDS PAGE method. Microorganisms had been an encouraging means of economical production of enzymes in large scale for the food and drug industry

Screening and partial purification of amylase from Aspergillus Niger isolated from deteriorated tomato (Lycopersicon Esculentum mill.) fruits

Amylases (EC 3.2.1.1) are cellwall degrading enzymes associated with the pathogenicity of microorganisms in the spoilage of tomato fruits. The use of amylase in many industries has made it very important to optimize production process to achieve maximum yields. Screening and partial purification of Amylase from Aspergillus niger isolated from tomato (Lycopersicon esculentum Mill.) fruits was studied. Amylase producing fungi were isolated from fresh tomatoes kept at ambient temperature (28±1˚C). Isolates were characterized on the basis of their morphological and cultural techniques. Partial purification of amylase was carried out by ammonium sulphate precipitation. The enzyme activity was determined and optimum conditions were obtained. The molecular weights of the crude and partially purified Amylase were determined by SDS PAGE method. A total of five isolates were obtained using basic screening technique for amylase activity, one of the isolates (Isolate code F2) exhibited maximum amylase activity. The fungi isolate code F2 was identified as Aspergillus niger. Optimum conditions for Amylase AMY F2 were ascertained at pH 6.0; temperature 30°C; substrate concentration of 0.3mg/ml, and time of heating of less than 10min. The molecular weights  f the crude and partially purified Amylase AMY F2 were found to be 55kDa and 35kDa respectively by SDS PAGE method. Microorganisms had been an encouraging means of economical production of enzymes in large scale for the food and drug industry. Keywords: Amylase, Partial Purification, Enzyme, Tomato Fruits Rendement et purification partielle de l'amylase de Aspergillus Niger isolé à partir de tomate déterioré (Lycopersicon Esculentum mill.) fruitsLes amylases (EC 3.2.1.1) sont des enzymes dégradant les parois cellulaires associées à la pathogénicité des microorganismes dans la détérioration des fruits à la tomate. L'utilisation de l'amylase dans de nombreuses industries a rendu très important d'optimiser le processus de production pour obtenir des rendements maximaux. Le dépistage et la purification partielle de l'amylase d'Aspergillus niger isolés à partir des fruits à la tomate (Lycopersicon esculentum Mill.) Ont été étudiés. Les champignons producteurs d'amylase ont été isolés à partir de tomates fraîches conservées à température ambiante (28 ± 1 ° C). Les isolats ont été caractérisés en fonction de leurs techniques morphologiques et culturelles. La purification partielle de l'amylase a été réalisée par précipitation au sulfate d'ammonium. L'activité enzymatique a été déterminée et des conditions optimales ont été obtenues. Les poids moléculaires de l'Amylase brut et partiellement purifiée ont été déterminés par un procédé SDS PAGE. Au total, cinq isolats ont été obtenus en utilisant une technique de dépistage basique pour l'activité amylase, l'un des isolats (code isolé F2) présentait une activité amylase maximale. Le code isolant F2 des Fusions a été identifié comme Aspergillus niger. Les conditions optimales pour Amylase AMY F2 ont été déterminées à pH 6,0; température 30 ° C; concentration de substrat de 0,3 mg / ml et temps de chauffage de moins de 10 min. On a trouvé que les poids moléculaires de l'amylase brute et partiellement purifiée étaient respectivement de 55 kDa et 35 kDa par le procédé SDS PAGE. Les microorganismes ont été un moyen encourageant de production économique d'enzymes à grande échelle pour l'industrie alimentaire et pharmaceutique.Mots-clés: Amylase, Purification partielle, Enzyme, Fruits tomate

Repair of spontaneous perineal laceration at delivery, a cultural taboo: a case report

Although genital trauma is a recognized maternal complication of vaginal birth, the presence of skilled birth attendants at delivery and judicious use of episiotomy has been shown to reduce this risk to the barest minimum. Prompt repair of these traumas averts the resultant complicationsthat may arise. A case of a booked 18-year-old nulliparous Guinea-Conakry woman with a  second-degree perineal tear who declined repairdue to a cultural reason is presented. The need for supervised delivery as well as immediate and long-term health implications of her decision isdiscussed.Keywords: Perineal laceration, Genital trauma,Skilled/unskilled birth attendant, vaginaldelivery/childbirth, custom, belief, haemorrhag

Studies on Staphylococcus aureus Isolated from Pimples

Background and Objective: Pimples (acne) are small skin lesions or inflammations of the skin. The most common factor causing acne is the hormonal changes that occur during adolescent and teenage years. Antibiotics are becoming less effective in the treatment of pimples due to increasing concerns of antibiotic resistance. This study was therefore carried out to characterize the isolates from the pimples of Covenant University Students and to determine their antibiotics sensitivity pattern. Materials and Methods: A total of 20 swab samples were obtained from male and female students with obvious signs of pimples in Covenant University, Ota, Ogun State, Nigeria. The samples obtained were cultured on Mannitol Salt Agar and incubated at 37EC. Pure isolates obtained were subjected to Gram staining and other biochemical tests for identification. The isolates were further subjected to antibiotics sensitivity tests using antibiotic dics. Results: Macroscopic examination indicated that the organisms were convex, smooth and shiny. Microscopic examination revealed that the isolates were positive after employing the Gram Staining technique and they appeared as grape-like clusters. Biochemical tests revealed that the isolates were Coagulase positive, Catalase positive, Urease positive, Citrate positive, Methyl-Red positive, Voges-Proskauer negative and negative upon starch hydrolysis. The sugar fermentation tests revealed that the isolates fermented Glucose, Maltose, Galactose, Sucrose and Lactose, respectively. The antibiotic susceptibility test showed that isolates were resistant to Cotrimazole, Cloxacillin, Erythromycin, Gentamycin, Augmentin, Streptomycin, Tetracycline and Chloramphenicol. Conclusion: The results therefore indicated that the isolates were Staphylococcus aureus and other staphylococci species. Indiscriminate use of antibiotics should be avoided to prevent the development of resistant strains of the Staphylococci genera and other pathogenic organisms

Isolation and Screening of Fungal Isolates from Bambara (Vigna Subterranea) Nuts for Tannase Production

Tannase (Tannin acyl hydrolase, EC 3.1.1.20) is an enzyme produced in the presence of tannic acid by various filamentous fungi. They are produced principally by fungi of the genus Aspergillus and Penicillium. The enzyme is used in the food and beverage industry as a clarifying agent for wines, beers and fruit juices. In Africa, billions of dollars are expended yearly on the importation of commercial enzymes for the food and pharmaceutical industries and this increases the cost of production and the finished goods. This study was carried out to isolate tannase producing fungal species using Bambara nuts as a substrate in a bid to finding alternatives to the importation of tannase. Fresh Bambara nuts were collected from different locations in Nigeria. They were cleaned, sorted and intermittently moistened with water to encourage fungal growth for fourteen days. The different fungi obtained after fourteen days were inoculated onto Potato Dextrose Agar plates and incubated at 25°C for five days. Subculturing of fungal isolates was carried out to obtain pure cultures of isolates. Tannilytic activity (hydrolysis of tannin) of isolates was assessed by inoculating them in media containing tannin. The plates were incubated at 25°C for 2-5 days after which the plates were observed and zones of hydrolysis measured. A total of eighteen isolates were obtained. They were all members of the Aspergillus genus. 56% (10) of the isolates were able to degrade tannin acid with mean zone of hydrolysis of 39mm ±23.7 mm (Range 10-70mm). This study established members of the Aspergillus genus isolated from Bambara nuts as viable fungi for application in the production of tannase. This study adds to existing reports on fungal production of tannase