Elie F. Itoba Tombo | Cape peninsula University of technology (original) (raw)

Papers by Elie F. Itoba Tombo

7th International Conference on Latest Trends in Engineering and Technology (ICLTET'2015) Nov. 26-27, 2015 Irene, Pretoria (South Africa), Nov 26, 2015

An endophytic cyanide resistant fungus Cunninghamella bertholletiae was isolated from cassava (Ma... more An endophytic cyanide resistant fungus Cunninghamella bertholletiae was isolated from cassava (Manihot esculenta) and cassava attached silt. The Cunninghamella sp. was sub-cultured into nutrient broth containing KCN (4mg/40mL) as a source of free cyanide. Samples were placed in an orbital (incubator) shaker at 30°C and 130rpm for 120 h. The cyanide resistant isolate was then successfully sub-cultured on PDA for 168 h at room temperature to determine if it can be regenerated after exposure to free cyanide. The fungus identification was based on; plate morphology, microscopic structure observation, nucleotide sequences and phylogenetic analysis. The identification revealed the fungus was Cunninghamella bertholletiae species from the Cunninghamella genus. The fungus has potential to be used as a free cyanide and total nitrogen degrader for environmental engineering applications. Cyanide, ammonium nitrogen and nitrate-nitrogen removal achieved were; 80%, 77.5% and 72.5%, within 120 h respectively.

BioResources

Grape pomace (GP) generated from the winery industry is one of the abundant agro-waste in the Wes... more Grape pomace (GP) generated from the winery industry is one of the abundant agro-waste in the Western Cape, South Africa and other regions globally. GP contains a significant quantity of holocelluloses that can be converted into fermentable total reducing sugars (TRS). This study reports on the recovery of TRS from GP treated Nepenthes mirabilis digestive fluids for mediated biovalorisation in comparison to a combination of conventional pretreatment methods (hot water pretreatment, dilute acid pretreatment, and cellulase pretreatment) in a single pot system. The recovery of TRS was facilitated while also reducing total residual phenolics (TRPCs) in the samples. Furthermore, powder X-ray diffraction (pXRD) was used to measure the crystallinity index and the functional groups of pre- and post-pre-treated GP were determined using Fourier-transform infrared spectroscopy (FTIR) to ascertain the efficiency of the pre-treatment methods, with quantification of lignin, holocellulose and ash ...

Fieldwork is known as a practical/physical way of teaching and learning. Thus, fieldwork is a com... more Fieldwork is known as a practical/physical way of teaching and learning. Thus, fieldwork is a complementary learning opportunity for students to participate in order to augment their theoretical learning. This research investigated the effectiveness of fieldwork as a tool to enhance the understanding of the Environmental Geology subject for the first year students in the Extended Curriculum Programme (ECP) at Cape Peninsula University of Technology in 2018. There were (n=39) students in the first year class. During the first semester, the students were exposed to theoretical learning only while, during the second semester, practical learning (fieldwork) was included to support theoretical learning. The results revealed a failure rate of 53% in the first semester. However, during the second semester the students' performance improved after exposure to fieldwork, which culminated in a pass rate of 76.7%. Therefore, the study concluded that fieldwork was critical in enhancing the students understanding, knowledge as well as skills and contributed enormously in improving the subject's pass rate.

Processes, 2019

To sustainably operate a biorefinery with a low cost input in a commercial setting, the hydrolysi... more To sustainably operate a biorefinery with a low cost input in a commercial setting, the hydrolysis of lignocellulosic biomass must be undertaken in a manner which will impart environmental tolerance while reducing fermenter inhibitors from the delignification process. The challenge lies with the highly recalcitrant lignin structure, which limits the conversion of the holocelluloses to fermentable total reducing sugars (TRS). Due to these challenges, sustainable and innovative methods to pre-treat biomass must be developed for delignocellulolytic operations. Herein, Nepenthes mirabilis digestive fluids shown to have ligninolytic, cellulolytic and xylanolytic activities were used as an enzyme cocktail to hydrolyse mixed agro-waste constituted by Citrus sinensis (orange), Malus domestica (apple) peels, cobs from Zea mays (maize) and Quercus robur (oak) yard waste. The digestive fluids contained carboxylesterases (529.41 ± 30.50 U/L), β-glucosidases (251.94 ± 11.48 U/L) and xylanases (3...

International Journal of Environmental Studies, 2016

Freshwater scarcity and river pollution has become a serious challenge for governments and

Environmental Monitoring and Assessment, 2017

Between the late 1940s and early 1950s, humans manufactured polyfluoroalkyl compounds (PFCs) usin... more Between the late 1940s and early 1950s, humans manufactured polyfluoroalkyl compounds (PFCs) using electrochemical fluorination and telomerisation technologies, whereby hydrogen atoms are substituted by fluorine atoms, thus, conferring unnatural and unique physicochemical properties to these compounds. Presently, there are wide ranges of PFCs and, owing to their bioaccumulative properties; they have been detected in various environmental matrices and in human sera. It has thus been suggested that they are hazardous. Hence, this review aims at highlighting the recent development in PFC research, with a particular focus on perfluorooctanoate (PFOA) and perfluorooctane sulfonate (PFOS), the most studied and predominantly found PFC in various environmental matrices, although recent reports have included perfluorobutane sulfonate (PFBS), which was previously regarded as innocuously harmless, when compared to its counterparts, PFOA and PFOS. As such, proper investigations are thus required for a better understanding of short-chain PFC substitutes, which have been suggested as suitable replacements to longchained PFCs, although these substitutes have also been suggested to pose various health risks comparable to those associated with long-chain PFCs. Similarly, several novel technologies, such as PFC reduction using Zero Valent Iron, including removal at point of use, have been proposed.

Toxics, 2019

It has been extensively demonstrated that plants accumulate organic substances emanating from var... more It has been extensively demonstrated that plants accumulate organic substances emanating from various sources, including soil and water. This fact suggests the potentiality of contamination of certain vital bioresources, such as medicinal plants, by persistent contaminants, such as perfluorooctanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and perfluorobutane sulfonate (PFBS). Hence, in this study, the propensity of Tagetes erecta L. (a commonly used medicinal plant) to accumulate PFOA, PFOS, and PFBS was determined using liquid chromatography/tandem mass spectrometry (LC–MS/MS-8030). From the results, PFOA, PFOS, and PFBS were detected in all the plant samples and concentration levels were found to be 94.83 ng/g, 5.03 ng/g, and 1.44 ng/g, respectively, with bioconcentration factor (BCF) ranges of 1.30 to 2.57, 13.67 to 72.33, and 0.16 to 0.31, respectively. Little evidence exists on the bioaccumulative susceptibility of medicinal plants to these persistent organic pollutants ...

Aflatoxin-Control, Analysis, Detection and Health Risks, Aug 30, 2017

SN Applied Sciences

Concerns for the environment and the desire to secure sustainable development are often too diffi... more Concerns for the environment and the desire to secure sustainable development are often too difficult to achieve considering the pressure put on natural environment. Worldwide, environment must be protected to ensure social and economic development for the benefit of the existing and forthcoming generations. Developing countries ought to prioritise the protection of the environment over the exploitation of natural resources and environmental pollution. South Africa has incorporated the concept of sustainable development in the Bill of Rights in the Constitution although the country is still facing difficulties. This research article aims to analyse environmental obligations and liabilities of an Electricity Distribution Company to improve sustainable development. Environmental obligations, liabilities and sustainable development are identified to realize research objectives and respond to research questions. A correlation coefficient test is performed to determine relationship between variables. Positive (+ 1) relationship between variables was identified. The results demonstrated the electricity distribution company's performance on environmental obligations and liabilities for environmental damaged caused. The results help to understand how to protect the environment, prevent financial liabilities and improve sustainable development. The Electricity Distribution Company had environmental incidents, which triggered environmental obligations and associated liabilities to which hinders the ability to achieve sustainable development in a comprehensive scale such as killing and endangering of protected bird species. Sustainable development will be negatively impacted as the results demonstrated that some environmental incidents were not reported and incidents occurrence hotspots not identified. Consequently, this impacts negatively on the environmental integrity. Environmental Management System could assist to address environmental obligations and associated liabilities to improve sustainable development. The system provide an international standard that ensure proper processes, risk identification, environmental aspects with the sole purpose to enhance environmental performance, achieve environmental obligations and fulfil environmental compliance obligations.

Environmental Monitoring and Assessment

Type 2 diabetes mellitus (T2DM) is the most common form of diabetes and it is characterized by hi... more Type 2 diabetes mellitus (T2DM) is the most common form of diabetes and it is characterized by high blood sugar and abnormal sera lipid levels. Although the specific reasons for the development of these abnormalities are still not well understood, traditionally, genetic and lifestyle behavior have been reported as the leading causes of this disease. In the last three decades, the number of diabetic patients has drastically increased worldwide, with current statistics suggesting the number is to double in the next two decades. To combat this incurable ailment, orthodox medicines, to which economically disadvantaged patients have minimal access to, have been used. Thus, a considerable amalgamation of medicinal plants has recently been proven to possess therapeutic capabilities to manage T2DM, and this has prompted studies primarily focusing on the healing aspect of these plants, and ultimately, their commercialization. Hence, this review aims to highlight the potential threat of pollutants, i.e., polyfluoroalkyl compounds (PFCs), endocrine disrupting chemicals (EDCs) and heavy metals, to medicinal plants, and their prospective impact on the phytomedicinal therapy strategies for T2DM. It is further suggested that auxiliary research be undertaken to better comprehend the factors that influence the uptake of these compounds by these plants. This should include a comprehensive risk assessment of phytomedicinal products destined for the treatment of T2DM. Regulations that control the use of PFC-precursors in certain developing countries are also long overdue.

In recent years, developing countries have increased their cassava (Manihot esculenta) production... more In recent years, developing countries have increased their cassava (Manihot esculenta) production for food security. Cassava contains cyanogen glycosides, mainly as linamarin, which through biocatalysis, i.e. enzyme hydrolysis, results in hydrogen cyanide (HCN). HCN is released into the environment through numerous ways with subsequent volatilisation. Thus, the HCN released during the period 2002-2013 was estimated between 0.025 × 10 −3 to 6.71 ppq (African), 0.012 × 10 −3 to 1.01 ppq (Asian) and 0.007 × 10 −3 to 0.920 × 10 −3 ppq (South American). Furthermore, a decade's (2014-2024) projection of HCN volatilisation displays increases of 60.5% (Africa), 57.7% (Asia) and 50.5% (South America) when compared with the current production. Furthermore, gas released during cassava plants' growth, i.e. HCN, NH 3 , and NO 2 , was quantified in healthy plants. Varying concentrations of HCN were released. These further indicated the presence of a pseudohalogenic gas in the environment -a contributor to climate change.

Eminent Association of Researchers in Engineering & Technology (EARET), 2019

Worldwide, cassava (Manhiot esculenta Crantz) is used for a multitude of reasons; as a main food ... more Worldwide, cassava (Manhiot esculenta Crantz) is used for a multitude of reasons; as a main food staple in Africa (Nigeria, Ghana, Cameroun etc.), Asia (Indonesia, Thailand, Cambodia etc.) and South America (Bazil, Paraguay etc.) as well as a source of energy for biogas and biofuel in Asia (China, Indonesia etc), South America (Brazil, Columbia etc.). A high demand of energy due to rapid urbanisation and development in developing countries, prompted governments, scientists and NGOs to seek other environmentally benign methods of energy production than fossil fuel based energy production systems. Thus, cassava has been identified as one of the suitable crops for biogas and biofuel production in order to mitigate the ensuing high energy demand. Like many developing countries, South Africa is interested in achieving sustainable energy and food supply, and cassava can serve as a source of both bioenergy bioethanol and biogas as well as food. However, the establishment/perennial production of cassava in developing countries generally and in South Africa particularly is facing potential challenges such as infertile land, pests problems, climate change and land availability for cultivation. However, some of this challenges can be overcome through availability of land for cassava cultivation, pest (insects) control, creation of local markets leading to job opportunities and communities acceptance of the crop for self-nourishment and industrial use.

A decade's (2014–2024) perspective on cassava's (Manihot esculenta Crantz) contribution to the gl... more A decade's (2014–2024) perspective on cassava's (Manihot esculenta Crantz) contribution to the global hydrogen cyanide load into the environment. online access on eprint link: http://www.tandfonline.com/eprint/IJdCxicbxuka3QMP2d6V/full

—An endophytic cyanide resistant fungus Cunninghamella bertholletiae was isolated from cassava (M... more —An endophytic cyanide resistant fungus Cunninghamella bertholletiae was isolated from cassava (Manihot esculenta) and cassava attached silt. The Cunninghamella sp. was sub-cultured into nutrient broth containing KCN (4mg/40mL) as a source of free cyanide. Samples were placed in an orbital (incubator) shaker at 30°C and 130rpm for 120 h. The cyanide resistant isolate was then successfully sub-cultured on PDA for 168 h at room temperature to determine if it can be regenerated after exposure to free cyanide. The fungus identification was based on; plate morphology, microscopic structure observation, nucleotide sequences and phylogenetic analysis. The identification revealed the fungus was Cunninghamella bertholletiae species from the Cunninghamella genus. The fungus has potential to be used as a free cyanide and total nitrogen degrader for environmental engineering applications. Cyanide, ammonium nitrogen and nitrate-nitrogen removal achieved were; 80%, 77.5% and 72.5%, within 120 h respectively.

Freshwater scarcity and river pollution has become a serious challenge for governments and scient... more Freshwater scarcity and river pollution has become a serious challenge for governments and scientists. Worldwide, governments have a responsibility to provide their populations with enough clean water for their domestic needs. Scientists will have an enormous task to find a way to purify polluted water, because of its vital role in human lives and an increasing demand for water consumption due to population growth. Although the water from the Bottelary River is used on a daily basis for farming activities, its pollution level as well as spatial distribution of effluents in the catchment is unknown. In the present study, I took monthly water samples from six sampling points for laboratory analysis. The laboratory determined concentration levels of phosphorous, chloride, nitrate, and nitrate nitrogen (NO 3 -N), as well as the chemical oxygen demand (COD) and suspended solids from the samples. On the same occasion's pH, dissolved oxygen, electrical conductivity and temperature were...

Cyanogen loading effects on terrestrial ecosystem and groundwater quality in agricultural soil E.... more Cyanogen loading effects on terrestrial ecosystem and groundwater quality in agricultural soil E. F. Itoba Tombo, S.K.O. Ntwampe, J.B. Mudumbi Faculty of Applied Sciences, Bioresource Engineering Research Group (BioERG), P.O. Box 652 Cape Town, 8000, South Africa; *Corresponding author: NtwampeS@cput.ac.za, Tel: +27 (0)21- 460 3430; Fax: +27 (0)21-460 3282 Abstract Cyanogen are important in inhibiting predation in various plant species; however, an increase in the concentration of these compounds in certain ecosystems (i.e. agricultural soil) can lead to soil degradation due the hydrolysis of these compounds to produce hydrogen cyanide (HCN). This paper focuses on cyanogenic glycosides’ movement in soil and groundwater, as well as the effects of these compounds on terrestrial ecosystems and the environment. Cyanogen loading in agricultural soil, impact negatively on the soil’s physical, chemical and biological properties. These compounds move from the subsurface through deposition, ...

Freshwater scarcity and river pollution has become a serious challenge for governments and

7th International Conference on Latest Trends in Engineering and Technology (ICLTET'2015) Nov. 26-27, 2015 Irene, Pretoria (South Africa), Nov 26, 2015

BioResources

Processes, 2019

International Journal of Environmental Studies, 2016

Freshwater scarcity and river pollution has become a serious challenge for governments and

Environmental Monitoring and Assessment, 2017

Toxics, 2019

Aflatoxin-Control, Analysis, Detection and Health Risks, Aug 30, 2017

SN Applied Sciences

Environmental Monitoring and Assessment

Eminent Association of Researchers in Engineering & Technology (EARET), 2019

Freshwater scarcity and river pollution has become a serious challenge for governments and

NOVA Science Publishers- Inc., New York, 2019

South Africa generally and Cape Town particularly is under fresh water stress and water sources s... more South Africa generally and Cape Town particularly is under fresh water stress and water sources such as the bottelary river requires pollutants management in order to sustain fresh in the city. Non Point Sources (NPS) pollution from the surface runoff and flowing water from the land use that enter the Bottelary river sytem is a matter of concern. The river receives diverse pollutants from the different land uses of the catchment, thereby negatively affecting its water quality. This study aim is to assess/compare the concentration of compounds such as; chloride, nitrate, total nitrogen, total phosphorus and water quality parameters (total suspended solids, electrical conductivity, dissolved oxygen) obtained from the NPS study area and the predicted concentrations generated by the model through GIS using ArcMap (ArcView). Prior to modelling and the analysis of the pollutants concentrations in the catchment, a land use/land cover map of the catchment was prepared using an integrated approach. The results of the study revealed differences between the modelled concentrations of pollutants and the measured water quality parameters. For example the concentration (C) of TSS and chloride obtained from the model were 55 mg/l and 10 mg/l, respectively, while the concentration for same elements measured from the river water samples are 196.2 mg/l TSS and 16.3 mg/l. The discrepancy could be due to contributions from point sources, interflow and ground water discharge into the river as well as the influence of seasonal variations since the study took place between the end of spring to the beginning of autumn.

Conference proceedings, 2020