introduction

Different ecological problems have been brought about by the growth of moss and algae in

different environments, significantly affecting water bodies, where these organisms interfere with water

and biodiversity. Chemical treatments conventionally used have adverse side effects on the surrounding

ecosystem. Ecological-friendly solutions are, therefore, emerging, among which is the use of natural

extracts. Citrus limon, or lemon, is one of the promising candidates as it has an extensive phytochemical

profile and documented antimicrobial properties. In this review, we try to synthesize current literature

findings related to lemon extract as a possible material in moss-algae removal, indicate gaps in the

knowledge, and suggest future directions.

Antimicrobial Properties of Lemon Extract

Studies have shown that lemon extract has high contents of phenolic compounds and essential

oils, which have been proven to possess various biological activities, including antimicrobial properties.

Such properties may be very useful in discovering a moss-algae remover since it can evade the

development of unwanted moss and algae by decomposing their cellular structures. The existence of

flavonoids and phenolic acids suggests that lemon extract could be applied usefully in breaking the

integrity of these organisms and improving the removal process (Klimek-Szczykutowicz et al., 2020).

Biotechnological Applications and Optimization

The implementation of lemon extract in environmentally friendly preparations follows the idea

of sustainable control practices for algae and moss. Researches in C. limon through biotechnologies can

unveil the best techniques for extraction and application to produce a strong remover (Maleki et al.,

2019). Implementation of advanced analytical techniques would therefore help determine some

metabolites in lemons, which function as algicidal or inhibitors to moss activity thereby enhancing the
preparation efficiency (Fang & Luo, 2018).

Synergistic Effects with Bio stimulants

While the antimicrobial efficacy of lemon is high, merging bio stimulants from seaweed with

microbial fermentation could enhance its strength (Bhatia, 2016). The mixture of lemon extract with

these bio stimulants is observed to promote plant health and their intrinsic ability to thwart the

establishment and growth of moss and algae, which may even result in a synergistic effect. Future

studies can research the interaction of lemon extract with various types of bio stimulants to make for a

more potent moss-algae remover.

Nutrient Control and Eutrophication

Nutrient over-enrichment is the most important cause of algal blooms, so it needs to be

adequately managed with suitable techniques. According to research, the antimicrobial property of

lemon extract could possibly be used to resist or decrease the impact of nutrient load in aquatic systems

(Wang et al., 2017). Control of nutrient loadings and utilization of a remover based on lemon can,

therefore, maintain the quality of water and prevent harmful blooms that present a key environmental

issue.

Photocatalytic Properties and Nanoparticle Synthesis

Recent studies in nanotechnology suggest that even lemon peel extract can be made use of to

synthesize TiO2 nanoparticles with photocatalytic properties (Nabi et al., 2020). The synthesized

particles were found to be very highly active for the degradation of organic materials and such

mechanisms could be employed with good success to the removal of moss and algae. Therefore, the

formulation could thus bring new methods to the treatment of algae and moss.
Knowledge Gaps and Future Directions

Although the preliminary results appear promising for the lemon extracts, there is still a whole

lot of information that has to be looked into. To start with, despite all the known antimicrobial

properties of lemons, not much work has been done regarding specifically testing its effectiveness for

various species of moss and algae. It would be excellent if in those studies, the researchers came up with

more knowledge about which species are mostly sensitive and which are less so, as well as the optimal

concentrations of lemon extracts necessary to remove the algal scum effectively.

It was never studied in depth how such an extract of lemon interacts with a set of other natural

compounds, including the bio stimulants. So, further studies might focus on the synergistic effect of

supplementing the lemon extract with other eco-friendly agents to increase its removing abilities of

moss and algea

Also, the environmental implications of the use of lemon extract solutions applied in the natural

ecosystem should be evaluated further. Long-term research should also be done to identify the

ecological consequences of the application of lemon extract on non-target organisms and the overall

health of the ecosystem.

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