Algae as an attractive source for cosmetics to counter environmental stress.

In recent times, a considerable amount of evidence has come to light regarding the effect that air pollution has on skin conditions. The human skin is the chief protection we have against environmental harm, whether biological, chemical, or physical. The stress from these environmental factors, along with internal influences, can be a cause of skin aging and enlarged pores, thinner skin, skin laxity, wrinkles, fine lines, dryness, and a more fragile dermal layer. This knowledge has led to greater demand for skin cosmetics and a requirement for natural raw ingredients with a high degree of safety and efficiency in combating skin complications. Recent developments in green technology have made the employment of naturally occurring bioactive compounds more popular, and novel extraction methods have ensured that the use of these compounds has greater compatibility with sustainable development principles. Thus, there is a demand for investigations into efficient non-harmful naturally occurring raw ingredients; compounds derived from algae could be beneficial in this area. Algae, both macroalgae and microalgae, consists of waterborne photosynthetic organisms that are potentially valuable as they have a range of bioactive compounds in their composition. Several beneficial metabolites can be obtained from algae, such as antioxidants, carotenoids, mycosporine-like amino acids (MAA), pigments, polysaccharides, and scytonemin. Various algae strains are now widely employed in skincare products for various purposes, such as a moisturizer, anti-wrinkle agent, texture-enhancing agents, or sunscreen. This research considers the environmental stresses on human skin and how they may be mitigated using cosmetics created using algae; special attention will be paid to external factors, both generally and specifically (amongst them light exposure and pollutants).

Synergistic effect of alkaline pretreatment and magnetite nanoparticle application on biogas production from rice straw.

Agricultural residues have high potential for biogas production, complex lignocellulosic structure is however the main hindrance in their bioconversion. This research focuses on combined effect of alkaline pretreatment of rice straw and magnetite (Fe3O4) nanoparticle application. Four doses of magnetite nanoparticles viz. 60, 80, 100 and 120 ppm were used in the anaerobic digestion of untreated and 2% NaOH pretreated rice straw. Compared to control, 2% NaOH pretreatment alone increased biogas and methane yield by 57 and 60% respectively. Magnetite nanoparticle (MNP) application alone gave maximum yield at 100 ppm which consisted of 37 and 33% more biogas and methane yield respectively. Combining the effect of 2% NaOH pretreatment and 120 ppm MNPs synergistically increased biogas and methane yield by 100 and 129% as compared to control. In addition, an energy assessment indicated a positive net gain of 3765 kJ for 2% NaOH pretreated rice straw with 120 ppm MNPs.