Keratinous poultry wastes valorization through novel keratinases of Chryseobacterium cucumeris and Sphingobacterium multivorum isolated from poultry sludge
- Hendrick, Qaphela https://orcid.org/0000-0001-7529-8129
- Authors: Hendrick, Qaphela https://orcid.org/0000-0001-7529-8129
- Date: 2021-02
- Subjects: Agricultural wastes , Factory and trade waste
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21400 , vital:48537
- Description: Annually, about 55percent of keratinous wastes are generated from various agro-industrial processing farms in South Africa. These wastes are difficult to handle due to structural integrity; hence, they constitute environmental issues due to the disposal means. Degradation of keratinous wastes using microbial-based technology has been deemed advantageous as it generates products with high-end values. Therefore, in this study, chicken feather and soil samples were collected from a local poultry farm, and bacteria were isolated using basal salt media supplemented with chicken feathers. The isolates were evaluated for proteolytic and keratinolytic potentials. The potent isolates were identified through 16S rDNA sequence and phylogenetic analysis. Fermentation media were optimized for enhanced keratinase production, and the amino acids liberated in the media during feather biodegradation were quantified. The biochemical properties of the keratinases produced were likewise determined. Ten (10) proteolytic bacteria were obtained from 20 isolates recovered from the samples with a diameter of halo on skimmed milk agar plate ranging from 15.5 ± 0.71 (mm) for isolate coded as PSW-15 to 28 ± 1.41 (mm) for isolate coded as PSW-08. The proteolytic bacteria showed variable keratinolytic potentials with percentage feather degradation that ranged from 29percent for PSW-11 to 84percent for PSW-14, and keratinase activity ranging from 99.99 U/mL for PSW-15 to 761.82 U/mL for PSW-14. The most potent isolates coded as PSW-14 and PSW-16 were identified as Chryseobacterium cucumeris FHN1 and Sphingobacterium multivorum HNFx. Their nucleotide sequences were submitted to the GenBank as MW16587 and MK82939, respectively. The optimization of fermentation conditions; C. cucumeris FHN1 showed improved activity at pH 5 - 6, inoculum size (4percent, v/v), chicken feather concentration (1percent, w/v), fermentation temperature (25o C). Similarly, S. multivorum HNFx showed optimal activity at pH 4.0, inoculum size (5percent, v/v), chicken feather concentration (2.5percent, w/v), and fermentation temperature (25-30 oC). C. cucumeris FHN1 and S. multivorum HNFx showed maximum keratinase production of 485.54 U/mL and 526.36 U/mL at 96 h and 72 h of incubation period respectively. Serine, aspartic acid, glutamic acid, and proline were the most abundant amino acids in the degraded chicken feathers, and upon quantitation, the following concentration was respectively obtained; 3.71, 3.4, 4.19 and 4.35 (g/100g sample) against C. cucumeris FHN1. While S. multivorum HNFx yielded aspartic acid (2.04 g/100g sample) and glutamic acid (2.0 g/100g sample) in high concentration. The keratinases showed optimal catalytic efficiency at pH and temperature of 8.0 and 90 oC, respectively. C. cucumeris FHN1 keratinase was inhibited by metal ion chelating agents; EDTA and 1,10-phenanthroline, suggesting a metallo-type of protease. The enzyme showed remarkable stability after pre-treatment with DTT, Fe2+, Fe3+ and Cu2+, with respective residual activity of 108percent, 102percent, 114percent, and 104percent. The S. multivorum HNFx keratinase; activity was not inhibited by serine- and metallo-protease inhibitors. It maintained the following residual activity against the following chemical agents; DTT (124percent), hydrogen peroxide (152percent), DMSO (161percent), triton X-100 (152percent), tween-80 (101percent), and metal ions; Fe2+ (128percent), Fe3+ (104percent), K+ (117percent), Ca2+ (104percent), Na+ (103percent), Ba2+ (115percent), Al3+ (126percent). The enzyme showed a substantial loss of catalytic efficiency after pre-incubation with various laundry detergents. The keratinases' remarkable stability in the presence of various chemical agents and metal ions tested suggests biotechnological and industrial application potentials. Consequently, the isolates portend industrial relevance for keratinous waste valorization and an excellent source of keratinases of industrial relevance. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-02
- Authors: Hendrick, Qaphela https://orcid.org/0000-0001-7529-8129
- Date: 2021-02
- Subjects: Agricultural wastes , Factory and trade waste
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/21400 , vital:48537
- Description: Annually, about 55percent of keratinous wastes are generated from various agro-industrial processing farms in South Africa. These wastes are difficult to handle due to structural integrity; hence, they constitute environmental issues due to the disposal means. Degradation of keratinous wastes using microbial-based technology has been deemed advantageous as it generates products with high-end values. Therefore, in this study, chicken feather and soil samples were collected from a local poultry farm, and bacteria were isolated using basal salt media supplemented with chicken feathers. The isolates were evaluated for proteolytic and keratinolytic potentials. The potent isolates were identified through 16S rDNA sequence and phylogenetic analysis. Fermentation media were optimized for enhanced keratinase production, and the amino acids liberated in the media during feather biodegradation were quantified. The biochemical properties of the keratinases produced were likewise determined. Ten (10) proteolytic bacteria were obtained from 20 isolates recovered from the samples with a diameter of halo on skimmed milk agar plate ranging from 15.5 ± 0.71 (mm) for isolate coded as PSW-15 to 28 ± 1.41 (mm) for isolate coded as PSW-08. The proteolytic bacteria showed variable keratinolytic potentials with percentage feather degradation that ranged from 29percent for PSW-11 to 84percent for PSW-14, and keratinase activity ranging from 99.99 U/mL for PSW-15 to 761.82 U/mL for PSW-14. The most potent isolates coded as PSW-14 and PSW-16 were identified as Chryseobacterium cucumeris FHN1 and Sphingobacterium multivorum HNFx. Their nucleotide sequences were submitted to the GenBank as MW16587 and MK82939, respectively. The optimization of fermentation conditions; C. cucumeris FHN1 showed improved activity at pH 5 - 6, inoculum size (4percent, v/v), chicken feather concentration (1percent, w/v), fermentation temperature (25o C). Similarly, S. multivorum HNFx showed optimal activity at pH 4.0, inoculum size (5percent, v/v), chicken feather concentration (2.5percent, w/v), and fermentation temperature (25-30 oC). C. cucumeris FHN1 and S. multivorum HNFx showed maximum keratinase production of 485.54 U/mL and 526.36 U/mL at 96 h and 72 h of incubation period respectively. Serine, aspartic acid, glutamic acid, and proline were the most abundant amino acids in the degraded chicken feathers, and upon quantitation, the following concentration was respectively obtained; 3.71, 3.4, 4.19 and 4.35 (g/100g sample) against C. cucumeris FHN1. While S. multivorum HNFx yielded aspartic acid (2.04 g/100g sample) and glutamic acid (2.0 g/100g sample) in high concentration. The keratinases showed optimal catalytic efficiency at pH and temperature of 8.0 and 90 oC, respectively. C. cucumeris FHN1 keratinase was inhibited by metal ion chelating agents; EDTA and 1,10-phenanthroline, suggesting a metallo-type of protease. The enzyme showed remarkable stability after pre-treatment with DTT, Fe2+, Fe3+ and Cu2+, with respective residual activity of 108percent, 102percent, 114percent, and 104percent. The S. multivorum HNFx keratinase; activity was not inhibited by serine- and metallo-protease inhibitors. It maintained the following residual activity against the following chemical agents; DTT (124percent), hydrogen peroxide (152percent), DMSO (161percent), triton X-100 (152percent), tween-80 (101percent), and metal ions; Fe2+ (128percent), Fe3+ (104percent), K+ (117percent), Ca2+ (104percent), Na+ (103percent), Ba2+ (115percent), Al3+ (126percent). The enzyme showed a substantial loss of catalytic efficiency after pre-incubation with various laundry detergents. The keratinases' remarkable stability in the presence of various chemical agents and metal ions tested suggests biotechnological and industrial application potentials. Consequently, the isolates portend industrial relevance for keratinous waste valorization and an excellent source of keratinases of industrial relevance. , Thesis (MSc) -- Faculty of Science and Agriculture, 2021
- Full Text:
- Date Issued: 2021-02
Knowledge and attitudes of professional nurses towards HIV and AIDS patients at the Libode District Health Services in the Eastern Cape Province
- Authors: Gedu, Grace Nontuthuzelo
- Date: 2011-12
- Subjects: Rural health services , AIDS (Disease)
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24610 , vital:63213
- Description: This study was conducted at the Libode District Health Services amongst professional nurses who render services to HIV and AIDS patients. Generally, caring for HIV positive patients, nurses need to be knowledgeable about the transmission of the HIV virus, in order to render quality care to the patients. They also need to be sensitive and to demonstrate positive attitudes towards the patients. It was unknown whether the professional nurses at the Libode District Health Services are knowledgeable or not regarding HIV and AIDS. Their attitudes towards the HIV positive patients, were also unknown. Not knowing the knowledge and attitude of professional nurses regarding HIV and AIDS has the potential to compromise the quality of nursing care rendered to the patients. The purpose of the study was to explore and describe the level of knowledge of professional nurses regarding HIV and AIDS well as their attitudes towards the HIV-positive patients so as to make recommendations for quality patient care based on the results. A quantitative explorative descriptive research design was used to examine the level of knowledge about HIV and AIDS as well as the attitudes of professional nurses to HIV and AIDS patients. The target populations were the 218 professional nurses working at the Libode District Health services who had nursed HIV positive patients. A simple random sampling method was used to select a sample of 120 participants. A structured self-administered questionnaire was used to obtain data. The questionnaire consisted of a section on the demographic profile of the participants, and two other sections for responses on knowledge and attitudes. Data were analyzed using Statistical Package for the Social Sciences (SPSS) version 17.0 software for consistency of the twenty (20) items in the questionnaire. Findings showed that nurses of Libode District Health Services had an approximately fair amount of knowledge. The majority (79percent) of participants scored above the cut-off point of 24. Twenty one percent (21percent) scored below 24. On attitude, the majority (76percent) had scored below the cut-off point of 36. Recommendations were that professional nurses of Libode District Health Services, need to be exposed to ongoing training on HIV and AIDS to increase their knowledge about HIV and AIDS and to ensure that they demonstrate positive attitudes towards HIV and AIDS patients. , Thesis (MSc) -- Faculty of Science and Agriculture, 2011
- Full Text:
- Date Issued: 2011-12
- Authors: Gedu, Grace Nontuthuzelo
- Date: 2011-12
- Subjects: Rural health services , AIDS (Disease)
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24610 , vital:63213
- Description: This study was conducted at the Libode District Health Services amongst professional nurses who render services to HIV and AIDS patients. Generally, caring for HIV positive patients, nurses need to be knowledgeable about the transmission of the HIV virus, in order to render quality care to the patients. They also need to be sensitive and to demonstrate positive attitudes towards the patients. It was unknown whether the professional nurses at the Libode District Health Services are knowledgeable or not regarding HIV and AIDS. Their attitudes towards the HIV positive patients, were also unknown. Not knowing the knowledge and attitude of professional nurses regarding HIV and AIDS has the potential to compromise the quality of nursing care rendered to the patients. The purpose of the study was to explore and describe the level of knowledge of professional nurses regarding HIV and AIDS well as their attitudes towards the HIV-positive patients so as to make recommendations for quality patient care based on the results. A quantitative explorative descriptive research design was used to examine the level of knowledge about HIV and AIDS as well as the attitudes of professional nurses to HIV and AIDS patients. The target populations were the 218 professional nurses working at the Libode District Health services who had nursed HIV positive patients. A simple random sampling method was used to select a sample of 120 participants. A structured self-administered questionnaire was used to obtain data. The questionnaire consisted of a section on the demographic profile of the participants, and two other sections for responses on knowledge and attitudes. Data were analyzed using Statistical Package for the Social Sciences (SPSS) version 17.0 software for consistency of the twenty (20) items in the questionnaire. Findings showed that nurses of Libode District Health Services had an approximately fair amount of knowledge. The majority (79percent) of participants scored above the cut-off point of 24. Twenty one percent (21percent) scored below 24. On attitude, the majority (76percent) had scored below the cut-off point of 36. Recommendations were that professional nurses of Libode District Health Services, need to be exposed to ongoing training on HIV and AIDS to increase their knowledge about HIV and AIDS and to ensure that they demonstrate positive attitudes towards HIV and AIDS patients. , Thesis (MSc) -- Faculty of Science and Agriculture, 2011
- Full Text:
- Date Issued: 2011-12
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