Mohammad Hssanabadi, Mohammad Sadegh Hassanvand, Mohammad Khanizadeh, Sasan Faridi, Adel Mokammel, Bita Malekian Esfahani, Ali Ahmadi Orkomi, Fatemeh Momeniha,
Volume 17, Issue 3 (12-2024)
Abstract
Background and Objective: The initial step in managing methane emissions is quantification. This study aims to comprehensively investigate the methods for estimating and measuring methane gas emissions in municipal solid waste landfills.
Materials and Methods: This systematic review includes studies published in English and Farsi between January 2005 and May 2023. English-language articles were included from PubMed, Web of Science, and Scopus databases, while Persian-language articles were included from SID, Majiran and Google Scholar.
Results: After evaluating the studies, 90 studies providing information on methods for measuring and estimating methane gas emissions in urban landfills were selected. The results showed that emission estimates based on widely used models like LandGEM and IPCC, despite being lower in cost and providing faster results, are often associated with relatively high uncertainty. Therefore, quantitative and qualitative methods of direct measurement are preferred for accurately determining methane emissions from landfills. The most commonly used methods for measuring greenhouse gases, especially methane from landfills, include direct reading equipment and closed flux determination chambers.
Conclusion: Estimating greenhouse gas emissions from primary sources allows responsible authorities to understand the current status of methane emissions and to formulate reduction strategies. The findings of estimated methane emissions from landfills can differ significantly from the actual measurements in some situations. Therefore, while these estimation methods are useful, fast and cost-effective tools, their inherent uncertainties should be considered when using them.
Kiandokht Ghanati, Amirali Aghamohammadi, Nader Akbari, Gazal Mirzaei, Mahsa Karimi-Sarzameleh, Mohammad Hadi Dehghani, Parisa Sadighara,
Volume 18, Issue 2 (9-2025)
Abstract
Background and Objective: A large amount of waste is generated from shrimp farming, primarily consisting of shrimp heads and shells. These wastes are often discharged into aquatic environments, where they act as pollutants and threaten the survival of other aquatic organisms. Therefore, reusing shrimp waste can help reduce water pollution and mitigate its environmental impact.
Material and Methods: In this study, carotenoids from shrimp waste were extracted using three methods: acidic, enzymatic, and alkaline. The amount of carotenoids was quantified for each extraction method. Their antioxidant effects on crude sunflower oil, in the presence of copper sulfate, were then evaluated using the TBARS assay. In this method, malondialdehyde levels are measured as an indicator of lipid oxidation. For this purpose, equal amounts of the extracted carotenoids were added to crude sunflower oil along with copper sulfate and placed on a shaker for 24 hours. Subsequently, the malondialdehyde content was measured.
Results: The highest carotenoid yield was obtained using the alkaline extraction method. In the TBARS assay, the alkaline method also demonstrated the greatest inhibition of lipid peroxidation in the presence of copper sulfate.
Conclusion: It can be concluded that the alkaline method is a simple and cost-effective approach for extracting carotenoids from shrimp waste. These carotenoids are bioactive and valuable compounds with potential applications in the pharmaceutical and food industries.
