International Science and Technology Journal of Namibia

Microbial load and mycotoxins from malted pearl millet and sorghum

Werner Embashu, Komeine K.M Nantanga — Wed, 12 Feb 2025 00:00:00 +0200

Microbial contamination of pearl millet and sorghum grains during the process of malting can compromise the safety of their resulting products. In Namibia, malts of pearl millet and sorghum are used in making oshikundu/ontaku, omalovu (opaque beer) and exclusively sorghum malts for other alcoholic traditional brews. There is limited research on microbial load and mycotoxins from malts of pearl millet intended for making oshikundu and possibly omalovu. Varieties of pearl millet (Okashana2, Kantana, and Kangara) and sorghum (Macia and Red sorghum) grains were germinated at 30°C for 4 days before drying at 50–55°C for 24 hours. Results showed that malts total microbial load was above the South African recommended limit 6.3 Log cfu/g (2 ×10⁷ cfu/g). However, cereal malts showed no contamination by Salmonella spp., Shigella and coliforms. Regulated mycotoxins aflatoxin, deoxynivalenol, fumonisin and zearalenone were detected from malts irrespective of the cereal. However, detected mycotoxins were below the legal limit set by the European Commission. These suggests that malts may potentially not be of safety concern when it comes to coliforms. Nonetheless, aerobic bacterial load, fungal load and mycotoxins need to be further reduced should the malt be used for oshikundu, omalovu and other low alcoholic brews.

Physico-chemical characteristics of soils at selected water-points in the Etosha National Pan, Namibia

Simon T. Angombe, Rosemary Shikangalah, Ezekeil G. Kwembeya — Fri, 13 Dec 2024 00:00:00 +0200

National parks are important systems for protecting biodiversity and ecosystems around the world. In Namibia, approximately 19% of the country’s land surface is proclaimed for protected areas including Etosha National Park (ENP). Managing the protected areas effectively and sustainably requires a great understanding of various components of the park, including the soils. This study aimed to understand the soil properties at different water-points in ENP (at Mushara, Rietfontein and Ombika water-points). Ten plots from each site were sampled, at different soil depths. Soil parameters such as soil texture, pH, electronic conductivity (EC), Cation Exchange Capacity (CEC), phosphorus (P), potassium (K) and organic matter content (OM) were measured and analysed. The results show that soils were poorer at Mushara than at Rietfontein and Ombika, in terms of OM, Zinc (Zn), EC, Iron (Fe), and CEC. Furthermore, Mushara had significantly more sand content than both Ombika and Rietfontein. However, there were no significant differences between Rietfontein and Ombika in terms of CEC, Zn, Calcium (Ca), pH, OM, iron, manganese, sodium (Na) and soil texture. All sites were largely dominated by sandy soil. However, Mushara had significantly more sand than both Ombika and Rietfontein, and significantly lower clay and silt content than Ombika and Rietfontein. The study concludes that the soil properties at assessed water-points might be influenced by vegetation communities, soil type and the total annual precipitation. Therefore, the results of this study can be used to refine conservation strategies and develop long-term monitoring programs. We recommend that future studies focus on the link between vegetation composition, above and below ground biomass and soil properties in ENP.

Exploring Methodologies for Assessing Land Degradation: A Comprehensive Review with Insights from Namibia

Tangeni Nakapipi, Ezequiel C Fabiano, Simon T Angombe — Wed, 12 Feb 2025 00:00:00 +0200

Land degradation represents a significant global environmental challenge, posing threats to ecosystem integrity, food security, and sustainable development. In this comprehensive review, we examine the methodologies employed for assessing land degradation, drawing insights from studies conducted in various regions, with a particular focus on Namibia. The study conducted a systematic literature search to gather information on land degradation assessment methods applied, 159 publications were reviewed. Utilizing the Mann-Kendall trend test, the study discerns notable trends in the publication landscape, providing valuable insights into the evolving research trajectories within this field. A prominent finding of this review is the dominance of remote sensing as the primary method utilized for assessing land degradation. In conclusion, this review underscores the imperative for future research endeavours to prioritize an in-depth exploration of land degradation processes, mechanisms, impacts as well as advocates for the adoption of innovative technologies and monitoring methods, the advancement of theoretical frameworks, and the promotion of multidisciplinary integrated system research. By embracing these recommendations, stakeholders can effectively address the multifaceted challenges posed by land degradation and advance towards sustainable land management practices.

A systematic literature review on blockchain-based titles registries for transparent land administration

Johannes Paavo, Rafael Rodríguez-Puentes — Wed, 12 Feb 2025 00:00:00 +0200

Traditional land registration processes in many countries are vulnerable and lack transparency, resulting in fraud, delays, and costs, especially in developing countries, and blockchain integration has been proposed as a potential solution in land administration systems. This paper addresses the challenges of the conventional system in its examination of this integration. Sweden stands out for its successful implementation of blockchain in land registry, owing to its advanced digital landscape. In contrast, developing countries such as Namibia face limited internet access, particularly in rural areas, which can hinder blockchain adoption. Georgia, Honduras, and Ghana have had success combating corruption through blockchain in land titling, while Kenya, Dubai, and several other countries are all actively exploring various blockchain applications in land administration. Despite its potential, this systematic literature review identifies a few challenges, such as identity verification, contract legality, co-ownership management, and adaptation to legal frameworks, that must be addressed before widespread blockchain implementation. The successes of Sweden, Georgia, Honduras, and Ghana illustrate both the potential and limitations of utilizing blockchain technology for land registry purposes. This study concludes that while blockchain's potential in land administration is evident, its realization requires careful consideration of legal, technological, and governmental complexities.

Determination of some selected heavy metals in catfish samples collected from some dams in Katsina state, Nigeria.

Mustapha Aminu, Abdulhamid Dahiru — Fri, 06 Dec 2024 00:00:00 +0200

This study was conducted to determine the concentrations of Cadmium, Cobalt, Copper, Nickel, Lead and Zinc in the Gill, Muscle and Tails of African catfish collected from Gwaigwaye, maska and Zobe dams in Katsina state, Nigeria across the dry and wet seasons. The collected tissues of African catfish were digested and analyzed for the toxic metals using microwave plasma atomic emission spectroscopy (MPAES). The levels of the metals obtained were compared with acceptable limits of world health organization(WHO) and Standard organization of Nigeria(SON).The metal levels were found in the following ranges, 0.0132±0.01 to 0.057±0.02 mg/kg for Cd, 0.00±0.00 to 0.887±0.01 mg/kg for Co, 0.090±0.00 to 0.26±0.00 mg/kg for Cu, 0.00±0.00 to 0.138±0.01 mg/kg for Ni, 0.00±0.00 to0.003±0.00 mg/kg for Pb and 0.133±0.04 to 0.855±0.01mg/kg for Zn for catfish gill in dry and wet seasons. Likewise, the concentration levels of the metals in catfish muscle in the following ranges were as follows 0.01±0.00 to 0.076±0.01 mg/kg for Cd, 0.00±0.00 to 0.048±0.01 mg/kg for Co, 0.066±0.04 to 0.108±0.03 mg/kg for Cu, 0.01±0.00 to 0.096±0.03 mg/kg for Ni, 0.00±0.00 to 0.01±0.00 mg/kg for Pb and 0.036±0.05 to 0.411±0.04 mg/kg for Zn . Similarly, 0.019±0.01 to 0.029±0.03 mg/kg for Cd, 0.00±0.00 to 0.091±0.01 mg/kg for Co, 0.079±0.01 to 0.133±0.03 mg/kg for Cu, 0.016±0.03 to 0.116±0.01 mg/kg for Ni, 0.00±0.00 to 0.023±0.03 mg/kg for Pb and 0.323±0.03 to1.08±0.01 mg/kg for Zn in catfish tail in both dry and wet seasons. The levels of the metals were found to be below the safe limits set by both WHO and SON. African catfish from gwaigwaye, maska and zobe dams are therefore safe for human consumption. The results of statistical analysis and P values<0.05 indicated no significant difference between the tissues of African catfish analyzed across all the dams in both seasons.