From natural methane sinks to the immobilisation of harmful heavy metals in rubber - a round-up of the latest research from SCI's journals
Taro in the limelight
The tuber crop taro is a staple food in Africa and parts of Asia. It is an important source of carbohydrate and valuable functional food, containing polysaccharide, vitamins, minerals and other substances. Taro polysaccharides, as a significant active ingredient in taro, have antioxidant, lipid-lowering, and immunomodulatory effects. Today, people are increasingly interested in food containing natural ingredients, making taro polysaccharides an attractive feedstock in the food, pharmaceutical, medical, and other fields.
This study reviews the extraction and purification, structural characterisation, functional activity, and application of taro polysaccharides.
Preparation, structural characteristics, and application of taro polysaccharides in food doi.org/10.1002/jsfa.12058
Keeping the clams clean
From Roman oyster farms to 11th Century American clam gardens, bivalve aquaculture is centuries old. Pests of bivalve aquaculture are a challenging problem that can reduce productivity, profitability and sustainability. A range of pest management approaches have been developed but a general absence of guiding frameworks has limited the scale and permanency of their implementation.
This review article looks at existing research and tools for pest management in bivalve aquaculture with a view to developing and implementing an integrated pest management (IPM) framework. Priorities for addressing data gaps and barriers to implementation include establishing meaningful pest-crop bioeconomic relationships for various bivalve farming systems and improving the efficacy and operational scale of treatment approaches.
Toward integrated pest management in bivalve aquaculture doi.org/10.1002/ps.7057
Rubber to the rescue
In recent years, there has been an increasing ecological and global public health concern associated with environmental contamination by heavy metals. Biosorption is a promising, cost-effective clean-up technology for treating wastewater laden with heavy metals. However, the commercial application of biosorption technologies has been limited because a large amount of toxic waste is left behind in this process.
Researchers at the University of Novi Sad, Serbia, have proposed and developed a possible solution: incineration of used adsorbent, followed by the use of the obtained ash as a filler in rubber production, immobilising the harmful substance from the environment. Analysis of the resultant rubber’s various properties reveals this novel approach is acceptable from an environmental safety perspective.
Use of exhausted biosorbent ash as ecofriendly filler in natural rubber doi.org/10.1002/pi.6423
Microbial astaxanthin, which is a high-value antioxidative pigment, is widely used in aquaculture for pigmentation, immunity enhancement and disease resistance. This novel model is regarded as an emerging way to alleviate environmental pollution and ecological problems that arise from the overuse of antibiotics or medicines in fish rearing. Therefore, cultivation of astaxanthin-rich microorganisms for aquaculture merits the attention of researchers and technicians.
This paper presents research progress in microbial strain screening, astaxanthin formation pathways and inducing conditions, and provides an in-depth discussion of the effect of extracted astaxanthin or astaxanthin-rich biomass on fish/shrimp rearing.
Microalga- and yeast-based astaxanthin production via nutrient recovery from wastewater for aquaculture practice: an emerging technology for sustainable development doi.org/10.1002/jctb.7164
Harnessing the potential of cow dung and leaves
Simultaneous thermochemical processing of waste biomass has the potential to reduce environmental pollution and create valuable products. This study examines the thermochemical conversion of African balsam (Daniella oliveri) leaves and cow dung – waste products commonly accessible in Africa.
The researchers produced biochar – a product advantageous for various agricultural and environmental applications – in a non-electrically powered, top-lit updraft reactor from the waste biomass at a 70% yield.
Characterisation of the resulting biochar revealed it to be thermally stable, with properties adequate for use as a soil additive. The findings of this study are helpful for attempts to manage solid wastes, reduce environmental pollution and produce valuable products, even in remote areas with no power supply.
Thermochemical Conversion of African balsam leaves-cow dung hybrid wastes into biochar doi.org/10.1002/bbb.2453
The natural methane sink
Methane (CH4) is a potent greenhouse gas, with a contribution to global warming of 0.5°C, according to the latest reports from the intergovernmental panel on climate change. To limit global warming to 1.5°C, as targeted by the Paris Agreement, the most effective strategy would be to rapidly reduce CH4 emissions, with a complementary strategy being the development of large-scale atmospheric CH4 removal methods.
This review article summarises methods for atmospheric CH4 removal, based on the hydroxyl radical (°OH), which is the principal natural sink of many gases in the atmosphere and on many water surfaces. It proposes several methods to enhance the °OH sink by physical means using water vapour and artificial UV radiation.
Atmospheric Removal of Methane by enhancing the natural hydroxyl radical sink doi.org/10.1002/ghg.2191
Significant reliability on imports and competency in energy efficiency activities may play a crucial role in determining an uninterrupted energy supply in the future. This article is related to the thermal engineering aspect of the hybrid heating unit that can be operated either by shallow geothermal heat or natural gas.
The thermal investigation is related to determining the fluctuation in the energy requirement if the unit is coupled with the gas boilers. The system was examined based on the thermodynamic principle, and a brief heat transfer analysis was performed to determine the convective heat gain/loss by the building along with the effectiveness of the heat exchangers involved in space heating.
Investigation of a Vertical Closed-loop Geothermal System for Heating an Educational Building doi.org/10.1002/ese3.1341