Mycosporine-like Amino Acids and their Biomolecular Properties
Page: 1-8 (8)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010003
PDF Price: $15
Abstract
Mycosporine-like amino acids (MAAs) are natural ultraviolet (UV)-
absorbing compounds that are attracting attention in the industrial field including
cosmetics and pharmaceuticals. This book provides a wide range of descriptions of
MAAs, from fundamentals to applications. In order to discuss the properties of MAAs,
an understanding of their chemical structures would be required. The purpose of this
chapter is to understand the basic molecular structure of MAAs. In general, MAAs
have structures in which amino acids are bound to the core structures of cyclohexenone
or cyclohexenimine. In addition to the basic structure, the resonance hybrid structures
of MAAs are also described here. Delocalization of electrons is considered to affect the
stability and the absorption maximum wavelength of MAA molecules. We will also
discuss the environmental factors that can affect the structure of MAAs. Finally,
databases of molecular structure information of MAAs will be described.
Distribution of MAAs
Page: 9-23 (15)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010004
PDF Price: $15
Abstract
Accumulation of mycosporine-like amino acids (MAAs) has been reported
in a wide range of species in nature, including microalgae, macroalgae, cyanobacteria,
phytoplankton, fungi, and some animals. This chapter describes the distribution of
MAAs with a focus on macroalgae and cyanobacteria. MAAs biosynthesized by
macroalgae have already been applied in cosmetic products, such as Helioguard 365
and Helinori. Macroalgae tend to accumulate multiple types of MAAs, and the types
and accumulation levels are affected by changes in environmental factors. Regarding
cyanobacteria, we focus on UV, salt, and osmotic stresses, temperature changes, and
drought stress as environmental factors, and describe the species in which the
accumulations of MAAs are induced by these stresses. UV-B irradiation is a common
environmental factor that can induce the accumulation of MAAs in cyanobacteria, but
induction by other abiotic stresses has been reported. These findings suggest that
MAAs act as a multifunctional molecule that responds to a variety of environmental
factors, not just as a UV absorber.
Biosynthetic Pathways of MAAs and their Regulatory Mechanisms
Page: 24-50 (27)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010005
PDF Price: $15
Abstract
The biosynthetic mechanism of mycosporine-like amino acids (MAAs) has
been roughly elucidated. In 2010, the genes responsible for MAA biosynthesis were
identified in cyanobacteria. In this chapter, first, we will describe the reaction
mechanisms responsible for the biosynthetic pathways of MAAs, mainly based on
results from cyanobacteria. Next, as a regulatory mechanism for MAA biosynthesis,
the response patterns of MAA accumulation in response to abiotic stresses, such as UV
irradiation, salt, and osmotic pressure, will be explained. There are many points to be
clarified regarding the detailed regulatory mechanisms, and further analyses are
awaited in the future. Because MAAs have useful activities in addition to UV
absorption, they are substances that are expected to be used in cosmetics and
pharmaceuticals. This chapter also includes discussions from the perspective of future
industrial production.
Analytical and Preparative Methods for MAAs
Page: 51-67 (17)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010006
PDF Price: $15
Abstract
This chapter describes the basics of analytical and preparative methods for
mycosporine-like amino acids (MAAs). For samples whose molecular structures are
known, high-performance liquid chromatography is widely used as a simple
quantitative or qualitative analytical method for MAAs. However, if the molecular
structures are unknown, they are often identified by combining several analytical
methods, such as liquid chromatography-mass spectrometry and nuclear magnetic
resonance analysis. In MAA preparation, the first key factor is how efficiently MAAs
can be obtained in the extraction process from biological samples. The second key
factor is how efficiently high-purity MAAs can be obtained from the separation
process. This chapter also discusses the production of MAAs from an industrial
perspective.
Biological Activities of MAAs and their Applications 1: UV-protective Activity of MAAs and their Application as Sunscreens
Page: 68-76 (9)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010007
PDF Price: $15
Abstract
In this chapter, we focus on the UV absorption characteristics of MAAs and
describe the application examples. UV rays that pass through the ozone layer and the
atmosphere and reach the surface of the Earth consist of UV-A and UV-B. Because
these rays are harmful to biomolecules, MAAs, which can efficiently absorb these
wavelength regions and detoxify their by-products, are promising natural organic
compounds such as sunscreens. Products containing MAAs extracted from red algae
are already on the market. With a focus on Helioguard 365 and HELINORI, the
biological effects of MAAs against UV irradiation will be described.
Biological Activities of MAAs and their Applications 2: Antioxidative Properties
Page: 77-87 (11)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010008
PDF Price: $15
Abstract
It is known that the generation of reactive oxygen species (ROS) caused by
UV irradiation and oxidative reactions accelerate skin aging. Substances that suppress
or eliminate the generation of ROS are called antioxidants. So far, various
mycosporine-like amino acids (MAAs) have been reported to have antioxidative
activities. To prevent damage to the skin caused by ROS and maintain the homeostasis
of the epidermis, skin cells have an endogenous antioxidant system consisting of
enzymatic reactions. Although many points are unclear about the regulatory
mechanisms, it has been suggested that MAAs are involved in the regulation of genes
encoding enzymes that are involved in this system. This chapter provides a
comprehensive overview of the antioxidant activities of MAAs.
Biological Activities of MAAs and their Applications 3: Anti-inflammatory Effects
Page: 88-93 (6)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010009
PDF Price: $15
Abstract
Inflammation is the defensive reaction system that occurs when the body
receives a harmful stimulus and tries to remove it. In general, the area where the
reaction occurs has a fever, swelling, redness, and pain. The stimuli that cause
inflammation are diverse but include UV irradiation and reactive oxygen species. This
chapter briefly describes the inflammatory response pathways caused by these stimuli.
After that, it outlines the effects of mycosporine-like amino acids (MAAs) on the
accumulation, activity, and regulation of factors contained in the inflammatory
pathway. Although research findings are accumulating, the molecular mechanisms are
still unknown. Details of the relationship between the molecular structures of MAAs
and their functions in the inflammatory pathway await further study.
Biological Activities of MAAs and their Applications 4: Anti-glycative Properties
Page: 94-101 (8)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010010
PDF Price: $15
Abstract
Advanced glycation end products (AGEs) are formed by a series of chemical
reactions initiated by non-enzymatic glycation reactions. In this process, the reducing
sugar binds to the free amino group of the protein. The formation of AGEs that
accompany the aging process is thought to be associated with various diseases such as
diabetes and Alzheimer's disease. A number of inhibitors derived from synthetic
compounds and natural products have been developed and evaluated to prevent the
formation of AGEs. Compared to synthetic compounds, natural products are
considered to be relatively safe for human consumption, so there is an increasing
demand for compounds derived from natural products. From this perspective, this
chapter focuses on mycosporine-like amino acids as naturally occurring inhibitors
against AGEs formation.
Biological Activities of MAAs and their Applications 5: Inhibition of Collagenase Activity
Page: 102-106 (5)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010011
PDF Price: $15
Abstract
Enzymes involved in the degradation of the extracellular matrix (ECM) are
deeply involved in skin aging. Compounds that suppress the degradation of collagen
and elastin, constituents of the ECM, are of significant value to the cosmetics field. So
far, more than 10 types of MAAs have been reported to inhibit the activity of
collagenase, which belong to the family of matrix metalloproteinases. It has been
suggested that the metal-chelating activity of MAAs is involved in these mechanisms
of action. However, MAAs have not been reported to have an inhibitory activity on
elastase. This chapter briefly summarizes these observations.
Biological Activities of MAAs and their Applications 6: Metal Chelating Abilities
Page: 107-110 (4)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010012
PDF Price: $15
Abstract
As mentioned in Chapters 8 and 9, the useful functions of MAAs, such as
the anti-glycative property and collagenase inhibitory activity, might be associated with
their metal chelating activity. Although there are few reports on the metal-chelating
activity of MAAs, a chelating model of MAAs and metal ions has recently been
proposed. This chapter briefly summarizes these observations.
Biological Activities of MAAs and their Applications 7: DNA Protective Property, Wound Healing Effects, Anti-Cancer Effects, And Applications in Horticulture and as a Film Material
Page: 111-114 (4)
Author: Hakuto Kageyama*
DOI: 10.2174/9789815136081123010013
PDF Price: $15
Abstract
This chapter describes the research findings on the DNA protection, wound
healing, and anti-cancer effects of MAAs and their use in horticulture and as a raw
material for film-type UV-blocking materials. These applications are additional to the
use of MAAs as sunscreen agents and pharmaceuticals applied to humans.
Introduction
Mycosporine-like amino acids (MAAs), have the property of absorbing ultraviolet rays, and are widely used as active ingredients in cosmetics such as sunscreens. They also have many bioactive properties that make them an attractive ingredient for pharmaceuticals and functional food. This book summarizes information about the molecular structures, activities and applications of mycosporine-like amino acids (MAAs). It aims to be an introductory book for undergraduate and graduate students in applied sciences, or as a handbook for researchers in pharmaceutical chemistry and cosmetics. Key features - 11 structured chapters covering the biochemistry of MAAs - Introduces readers to biochemical and synthetic pathways of MAAs - Presents information on many bioactive properties of MAAs including helioprotective, anti-inflammatory, antioxidant and anti-collagenase effects - Simple, clear explanations for learners - Academic and scholarly references for advanced readers - Illustrated appendices