The future feasibility of bioethanol as an alternative to fossil fuels will largely depend on its economic advantages. At present, microalgae biomass production does not permit commercial production of bioethanol [99]. The low carbohydrate content in algal biomass is a strong limitation. The amount of algal carbohydrate can be induced to reach a higher level than normal, either by controlling environment conditions or by introducing genetic modifications. Growing algal cells under certain stress conditions can alter certain biochemical pathways, leading to enhanced synthesis of carbohydrates [100, 101]. These stress conditions may be limitation of nutrients, such as nitrogen and phosphorus; change in light intensity, salinity of the growth media, or pH; or application of UV radiation. Regarding genetic modification, metabolic pathways inside the algal cell can be modified to increase the production of carbohydrates, lipids, and other important compounds of interest [102, 103]. It is important to select microalgae strains that allow easy, multidimensional modification of biochemical pathways. This novel approach uses new, powerful, rapidly evolving genetic engineering tools to identify and selectively modify the right genes.
Weeds are a significant problem in crop production and their management inmodern agriculture is crucial to avoid yield losses and ensure foodsecurity. Intensive agricultural practices, changing climate, and naturaldisasters affect weed dynamics and that requires a change in weed managementprotocols. The existing manual control options are no longer viable becauseof labor shortages; chemical control options are limited by ecodegradation,health hazards, and development of herbicide resistance in weeds. We aretherefore reviewing some potential nonconventional weed managementstrategies for modern agriculture that are viable, feasible, and efficient.Improvement in tillage regimes has long been identified as an impressiveweed-control measure. Harvest weed seed control and seed predation have beenshown as potential tools for reducing weed emergence and seed bank reserves.Development in the field of allelopathy for weed management has led to newtechniques for weed control. The remarkable role of biotechnologicaladvancements in developing herbicide-resistant crops, bioherbicides, andharnessing the allelopathic potential of crops is also worth mentioning in amodern weed management program. Thermal weed management has also beenobserved as a useful technique, especially under conservation agriculturesystems. Last, precision weed management has been elaborated with sufficientdetails. The role of remote sensing, modeling, and robotics as an integralpart of precision weed management has been highlighted in a realisticmanner. All these strategies are viable for today's agriculture; however,site-specific selection and the use of right combinations will be the key tosuccess. No single strategy is perfect, and therefore an integrated approachmay provide better results. Future research is needed to explore thepotential of these strategies and to optimize them on technological andcultural bases. The adoption of such methods may improve the efficiency ofcropping systems under sustainable and conservation practices.
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The production of free radicals is an integral part of metabolism, which if unchecked, cause oxidative stress. Oxidative stress damage to lipid, protein, nucleic acids and carbohydrates are deleterious and concomitant. There are substantial accumulation of data suggest that oxidative stress biomarkers can not only determine the extent of oxidative injury, but also indicate the source of oxidant [5]. Biomarkers of oxidative stress are also important for predicating the consequences of oxidation and for providing a basis for designing appropriate intervention to prevent or alleviate injury. The most intuitive goals for a biomarker are to help the diagnose symptomatic and pre-symptomatic disease and to provide surrogate endpoints to demonstrate clinical efficacy of new treatments. In the diverse nature of disease like SLE, single biomarker analysis can not reflect the whole body oxidative damage and a series of biomarkers may be required and each needs to validate in prospective clinical studies. A valid biomarker should be [78, 79]:
HNE is a major and toxic aldehyde generated by free radical attack on polyunsaturated fatty acids (arachidonic, linoleic, and linolenic acids) and is considered a second toxic messenger of oxygen free radicals [85]. It is enduringly formed at basal concentrations under physiologic conditions, but its production is greatly enhanced in lipid peroxidation condition. Level of HNE can be measured by methods like HPLC, GM-CS, however, ELISA is the most used method in SLE patients due to the simplicity of the assay. Increased levels of HNE have been demonstrated in the MRL/lpr as well as in SLE and associated with increased onset of disease [86, 87]. Increased HNE has been shown to exhibit facile reactivity with various biomolecules, including proteins and DNA, and is regarded as a sensitive marker for evaluating oxidative stress in disease state [65, 87]. However, a longitudinal study may be helpful to understand its association with clinical feature in SLE patients. 2ff7e9595c
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