LAUSR

The global outbreak of the infectious coronavirus has brought upon detrimental impacts, both good and bad, to the environment. During the initial stages of the virus spread, lockdown measures were put in place in countries worldwide, resulting in a mass drop of air pollution from the industries that have halted goods production. The sudden pause to human activities led to less transport movements which provided a beneficial short-term effect on the environment from cleaner air to less noise generations.[1] However, the impact on the economy and livelihood of citizens took a major blow and the eventual easing of lockdown measures equalled to life returning to normalcy. In just the short span of the lockdown period, the levels of air pollutions have reduced significantly, reflecting the influence of the world’s manufacturing andprocessing capacity to the environment.[2] Thus, the emphasize of urban sustainability in future developments are called-for. One solution to improve and protect the environment and biodiversity, is the creation of green cities. A green city will have adequatewater storage, reduced pollutions and provides a climate-proof and sustainable setting for nature to thrive. Green cities, or also known as sustainable cities, are a prospective solution to lower the environmental impacts caused by daily human activities. Many urban areas across the world strive to be part of an eco-city that consider the social, economic, environmental impact and welfare of the populations, in order to provide a better quality of life for the future generations.[3] The essential elements to create a green city is to reduce the waste produced, promote recycling, lower emissions, improve housing density and develop the local business in a sustainable manner. The classification of a green city varies in each continent. Some citiesmay adapt efficient transportation systems that will lead to reduced traffic, energy consumption and pollution.While, other citiesmay shift towards renewable energy sources, such as geothermal and hydropower, to supply for the city’s heat and electricity. There are also cities that have ban plastic usage to reduce pollution, while others have invested in solar equipment utilization to generate clean energy. Nevertheless, all these cities have taken part in some form of environmental policy with the common interest to preserve the natural environment and achieve the sustainability goals. While there are various systems that can be implemented in the bid to develop a green city, one of the interesting ways to create a selfsustained green city is to make use of plant sources which can provide cleaner air quality and reduce the carbon footprint in the city. A suitable plant that is renewable and could potentially be part of the creation of a green city is microalgae. Unlike common plant and tree species, microalgae are aquatic organisms that work like plants, where microalgae conduct photosynthesis to produce oxygen and energy. Microalgae are themicroscopic versionof algae andhave long emerged as a promising source for biomass production, which are then processed into biofuels, food biomolecules, nutritional feed and other biochemical ingredients.[4] The requirements for microalgae survival are simply water, carbon dioxide, sunlight, and minimal nutrients, where most of these are easily available. This renewable plant source can provide a breakthrough in green chemical synthesis, contributing to the sustainable development of chemical processes, energy conser-