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1.
Heliyon ; 7(6): e07241, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34189300

RESUMO

A consortium of microbial community was used for the treatment of acid mine drainage wastewater laden with sulphate and heavy metals. The wastewater was treated in an anaerobic continuously stirred tank bioreactor. The microbial community activity increased the pH from 5.6 to 6.5, and improved sulphate removal up to 85% from an initial sulphate concentration of 8080 mg S O 4 2 - /L in a continuous mode, following enrichment for 21 d. The maximum heavy metal removal percentage was observed for Cd (98%), Al (97%), Mn (95%), Pb (94%), Sr (94%) and Cu (91%). The microbial community showed synergy between strictly anaerobic and facultative Firmicutes sp., which were responsible for the bioreactor performance. The biochemical reaction indicated the microbial community has a wider range of substrates dominated by metallo-aminopeptidases.

2.
Chemosphere ; 277: 130310, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33774241

RESUMO

Sewage sludge has long been regarded as a hazardous waste by virtue of the loaded heavy metals and pathogens. Recently, more advanced technologies are introduced to make use of the nutrients from this hazardous sludge. Successful recovery of sludge's carbon content could significantly convert waste to energy and promote energy sustainability. Meanwhile, the recovery of nitrogen and trace minerals allows the production of fertilizers. This review is elucidating the performances of modern thermal treatment technologies in recovering resources from sewage sludge while reducing its environmental impacts. Exhaustive investigations show that most modern technologies are capable of recovering sludge's carbon content for energy generation. Concurrently, the technologies could as well stabilize heavy metals, destroy harmful pathogens, and reduce the volume of sludge to minimize the environmental impacts. Nevertheless, the high initial investment cost still poses a huge hurdle for many developing countries. Since the initial investment cost is inevitable, the future works should focus on improving the profit margin of thermal technologies; so that it would be more financially attractive. This can be done through process optimization, improved process design as well as the use of suitable co-substrates, additives, and catalyst as propounded in the review.


Assuntos
Metais Pesados , Esgotos , Fertilizantes , Nitrogênio
3.
Environ Technol ; 42(25): 3955-3962, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32419642

RESUMO

This study investigated the effect of carbon sources (n = 2) on the performance of a microbial community in an anaerobic moving-bed biofilm reactor (MBBR) treating acid mine drainage (AMD). The 1.5 L anaerobic MBBR was operated across a range of hydraulic retention times - HRT's (3-18 days), using different substrates, i.e. brewing wastewater and lactate as sole carbon sources and electron donors. Maximum sulphate reduction and chemical oxygen demand (COD) consumption rate was 21.94 and 24.28 mg SO42- L-1 h-1, and 0.473 and 0.697 mg COD L-1 d-1 for brewing wastewater and lactate supplemented bioreactors, respectively, at an HRT of 3 days. The maximum COD/SO42- ratio was found to be 2.564 in the bioreactor supplemented with brewing wastewater at an HRT of 15 days. The metal removal above 70% in the system supplemented with brewing wastewater followed the order; Be2+ > Fe2+ > Sr2+ > Pb2+ > Mg2+ > Cu2+ > Zn2+ > Li1+ > Ca2+ in comparison to the system supplemented with lactate, Be2+ > Fe2+ > Sr2+ > Mg2+ > Cu2+ > Li1+ > Zn2+ > Pb2+ after an HRT of 18 days. Complete removal of beryllium (II) was observed irrespective of the carbon source used. The results clearly showed that brewing wastewater can be deployed as a nutritional supplement in environmental remediation of AMD.


Assuntos
Microbiota , Águas Residuárias , Anaerobiose , Biofilmes , Reatores Biológicos , Carbono , Ácido Láctico , Eliminação de Resíduos Líquidos
4.
Artigo em Inglês | MEDLINE | ID: mdl-33255455

RESUMO

Dyslipidaemia, an irregular aggregate of lipids in the blood is common in diabetes and cardiovascular disease sufferers. A cross-sectional study on the prevalence of dyslipidaemia was performed among type 2 diabetes mellitus (T2DM) patients in the Western Cape, South Africa. Patients (n = 100) that participated in the study were within the age range of 19-68 years, of whom 89% were observed to have serum lipid abnormalities. Out of the 100 patients, 56%, 64%, 61%, and 65% were recorded to have high total cholesterol (TC), hypertriglycemia, increased low-density lipoproteins cholesterol (LDL-C), and reduced high-density lipoproteins cholesterol (HDL-C), respectively. In male diabetic patients, a marked prevalence of (94%) dyslipidemia was noted, of which 52% were affected by high TC (5.3-7.9 mmol/L), with 70% having a high level of triglyceride (TG) [1.72-7.34 mmol/L], while 60% had a high LDL-C (3.1-5.5 mmol/L), including 78% with low HDL-C (0.7-1.1 mmol/L). In comparison, 84% of diabetic females had dyslipidemia, with high TC (5.1-8.1 mmol/L), hypertriglycemia (1.73-8.63 mmol/L), high LDL-C (3.1-5.6 mmol/L), and low levels of HDL-C (0.8-1.1 mmol/L) affecting 60%, 58%, 62%, and 52% of the patients, respectively. This study showed the importance of screening and the regular surveillance of dyslipidaemia in T2DM patients as there is a paucity of data on it in Africa.


Assuntos
Diabetes Mellitus Tipo 2 , Dislipidemias , Adulto , Idoso , HDL-Colesterol , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/epidemiologia , Dislipidemias/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , África do Sul/epidemiologia , Triglicerídeos , Adulto Jovem
5.
Environ Sci Pollut Res Int ; 27(19): 24574-24581, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32350833

RESUMO

The anaerobic decomposition of coconut endosperm waste (CEW), residue derived from cooking, has been insidiously spewing greenhouse gasses. Thus, the bioconversion of CEW via in situ fermentation by exo-microbes from commercial Rid-X and subsequent valorization by black soldier fly larvae (BSFL) was the primary objective of the current study to gain sustainable larval lipid and protein. Accordingly, various concentrations of exo-microbes were separately homogenized with CEW to perform fermentation amidst feeding to BSFL. It was found that 2.50% of exo-microbes was the threshold amount entailed to assuage competition between exo-microbes and BSFL for common nutrients. The presence of remnant nutrients exuded from the fermentation using 2.50% of exo-microbes was confirmed to promote BSFL growth measured as maximum larval weight gained and growth rate. Although the BSFL could accumulate the highest protein (16 mg/larva) upon feeding with CEW containing 2.50% of exo-microbes, more lipid (13 mg/larva) was stored in employing 0.10% of exo-microbes because of minimum loss to metabolic processes while prolonging the BSFL in its 5th instar stage.


Assuntos
Simuliidae , Animais , Cocos , Endosperma , Larva , Lipídeos
6.
Proteomes ; 8(2)2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32326470

RESUMO

A reference range is an essential part of clinical laboratory test interpretation and patient care. The levels of total serum protein (TSP) are measured in sera to assess nutritional, liver, and kidney disorders. This study determined the TSP reference range with respect to gender, age, and region in Namibia. A retrospective cross-sectional study was conducted to determine the TSP reference range among 78,477 healthy participants within the ages of less than one year to more than 65 yrs in 14 regions of Namibia. The reference range of TSP was 51-91 g/L for females and 51-92 g/L for males. A reduced TSP range of 48.00-85.55 g/L (2.5-97.5 percentiles) was established at <1-5 years and increased towards adolescence. An uttermost range of 54-93 g/L was observed from 36-65 years of age. At the age >65 years; a steady decline in the reference range (51.00-89 g/L) was recorded. An upper TSP range of 53-92 g/L (2.5-97.5 percentiles) was detected in Erongo, Zambezi, Hardap, Kavango East, and a comparable trend was also seen in Omusati with a 54-91 g/L range. Meanwhile; a reduced TSP range of 50-89 g/L was identified in Ohangwena. This study showed that gender, age, and geographical location can impact TSP levels with a significant clinical difference (p < 0.05) between each category.

7.
Foods ; 8(8)2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31374870

RESUMO

Optimum fermentor conditions are essential for desired microbial growth and activity in fermentations. In balsamic vinegar fermentation systems, the microorganisms used must endure several stressful conditions including high sugar concentration, low water activity, high osmotic pressure and high acetic acid concentration. Consequently, the present study was aimed at improving the performance of a microbial consortium of non-Saccharomyces yeast and acetic acid bacteria during balsamic-styled vinegar fermentation. Cell immobilization via adsorption on corncobs and oak wood chips in combination with aeration and agitation effects, have never been tested during balsamic-styled vinegar fermentation. Therefore, fermentations were initially conducted under static conditions without aeration with successive fermentations also being subjected to low (0.15 vvm min-1) and high (0.3 vvm min-1) aeration. The results showed improved acetification rates when cells were immobilized on corncobs under static conditions. Low aeration showed better acetification rates (1.45-1.56 g·L·day-1), while only free-floating cells were able to complete fermentations (1.2 g·L·day-1) under high aeration conditions. Overall, cells immobilized on corncobs showed higher acetification rates of 1.56 and 2.7 g·L·day-1 under low aeration and static fermentations, respectively. Oak wood chips were determined to be less efficient adsorbents due to their relatively smooth surface, while the rough surface and porosity of corncobs led to improved adsorption and, therefore, enhanced acetification rates.

8.
Data Brief ; 25: 104135, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31294068

RESUMO

The metagenomic data presented herein contains the bacterial community profile of a drinking water supply system (DWSS) supplying O'Kiep, Namaqualand, South Africa. Representative samples from the source (Orange River) to the point of use (O'Kiep), through a 150km DWSS used for drinking water distribution were analysed for bacterial content. PCR amplification of the 16S rRNA V1-V3 regions was undertaken using oligonucleotide primers 27F and 518R subsequent to DNA extraction. The PCR amplicons were processed using the illumina® reaction kits as per manufactures guidelines and sequenced using the illumina® MiSeq-2000, by means of MiSeq V3 kit. The data obtained was processed using a bioinformatics QIIME software with a compatible fast nucleic acid (fna) file. The raw sequences were deposited at the National Centre of Biotechnology (NCBI) and the Sequence Read Archive (SRA) database, obtaining accession numbers for each species identified.

9.
Foods ; 8(2)2019 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-30717320

RESUMO

Microbial spoilage causes food losses in the food industry and as such, the use of synthetic chemical preservatives is still required. The current study proposes the use of agro-waste, i.e., grape pomace extracts (GPE), as production medium for biopreservation compounds. Production kinetics, subsequent to optimization using response surface methodology (RSM) for biopreservation compounds production was studied for three yeasts using GPE broth as a fermentation medium. The results showed that the highest volumetric zone of inhibition (VZI) was 1.24 L contaminated solidified media (CSM) per mL biopreservation compounds used (BCU) when Candida pyralidae Y1117 was inoculated in a pH 3-diluted GPE broth (150 g L-1) incubated at 25 °C for 24 h. Similar conditions were applied for Pichia kluyveri Y1125 and P. kluyveri Y1164, albeit under slightly elongated fermentation periods (up to 28 h), prior to the attainment of a maximum VZI of only 0.72 and 0.76 L CSM mL-1 ACU, respectively. The potential biopreservation compounds produced were identified to be isoamyl acetate, isoamyl alcohol, 2-phenyl ethylacetate and 2-phenyl ethanol.

10.
Data Brief ; 17: 275-278, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29876392

RESUMO

This data article presents the utilization of sulphates as an indirect technique for the assessment of microbial growth, activity and SCN- biodegradation efficiency since the TDO were observed to be unable to utilise the produced sulphates as a source of sulphur (Mekuto e al., 2017) [1] The TDO demonstrated complete SCN- biodegradation while also utilizing the produced ammonium. The production of SO42- from SCN- biodegradation had a good correlation in comparison to the traditional methods of assessing microbial growth and activity i.e. direct cell counts (DCC), heterotrophic counts (CFU) and fluorescein production from fluorescein diacetate (FDA). The concentration of the produced SO42- demonstrated a similar logarithmic trend with the FDA, DCC and CFU techniques, thus confirming that the production of SO42- from SCN- biodegradation systems can be utilised as an indirect technique for the assessment of microbial growth, activity and SCN- biodegradation performance.

11.
Data Brief ; 14: 84-87, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28861443

RESUMO

Sustainability of nutrient requirements for microbial proliferation on a large scale is a challenge in bioremediation processes. This article presents data on biochemical properties of a free cyanide resistant and total nitrogen assimilating fungal isolate from the rhizosphere of Zeamays (maize) growing in soil contaminated with a cyanide-based pesticide. DNA extracted from this isolate were PCR amplified using universal primers; TEF1-α and ITS. The raw sequence files are available on the NCBI database. Characterisation using biochemical data was obtained using colorimetric reagents analysed with VITEK® 2 software version 7.01. The data will be informative in selection of biocatalyst for environmental engineering application.

12.
Data Brief ; 13: 738-741, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28748209

RESUMO

The data presented in this article contains the bacterial community structure of the free cyanide (CN-) and thiocyanate (SCN-) degrading organisms that were isolated from electroplating wastewater and synthetic SCN- containing wastewater. PCR amplification of the 16S rRNA V1-V3 regions was undertaken using the 27F and 518R oligonucleotide primers following the metacommunity DNA extraction procedure. The PCR amplicons were processed using the illumina® reaction kits as per manufacturer׳s instruction and sequenced using the illumina® MiSeq-2000, using the MiSeq V3 kit. The data was processed using bioinformatics tools such as QIIME and the raw sequence files are available via NCBI׳s Sequence Read Archive (SRA) database.

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