There are three chief categories of photosynthetic, pigments, chlorophylls ( ch1 ) ( including bacteriochlorophylls, Bch1 ) , carotenoids and phycobilins ( Phycobilipoteins, PBPS ) . All species capable of transporting out photosynthesis contain one or more type of chlorophyll or bacterio-chlorophyll and carotenoids. Phycobilins are found merely in the ruddy algae and bluish green algae or blue-green algae.
Chlorophyll
The alone reactions of photosynthesis are mediated by a category of molecules termed chlorophyll. Green algae and higher workss contain two types of chlorophylls, Chl a and Chl B. Both are soluble in organic dissolvers. Chl a is present in all photosynthetic beings in which there is development of O during photosynthesis.
The undermentioned types of Chl a are known. Chl a 660, Chl a 670, Chl a 680, Chl a 685, Chl a 690 and Chl a 700 – 720. The short wavelength signifiers of Chla are chiefly presented in PSII, while the long wavelength signifiers are chiefly present in PSI. Chl B is present in all green algae and higher workss. Most of the Chl B is present in PSII. There are two signifiers of chlorophyll-b, Chlb640 and Chlb650.
Carotenoids
The carotenoids are found in about all photosynthetic beings. They are xanthous and orange pigments which are soluble in organic dissolvers. There are two types of carotenoids, viz. provitamin As and carotenols. Provitamin as, eg. ?-carotene and hydrocarbons. Most of the provitamin As are present in PSI. Carotenols ( Xanthophylls ) are alcohol. Most of the luteins are present in PSII. Carotenoids, chlorophyll, xanthophylls etc. are widely distributed in workss.
In the last two decennaries, there has been a great concern, about the depletion of stratospheric ozone bed ( O3 ) , caused chiefly by the extended release of chlorofluro C compounds and other ozone consuming substances. Stratospheric ozone, a thin gaseous bed, strongly attenuates UV ( UV ) radiation shorter than 310 nanometer. Decrease in stratospheric ozone allow the incursion of more solar UV radiation into the ambiance to make the Earth ‘s surface for every 1 % of ozone loss, 1 – 2 % more UV reaches the land ( Santhi, 2004 ) .
Due to optical features of ozone, it is the UV-B radiation, which is likely to increase at the Earth ‘s surface as a effect of a lessening in stratospheric ozone concentration ( Frederick et al. , 1989 ) . The effects of UVB on aquatic ecosystems are strongly dependent on the optical belongingss of the H2O organic structure ( Holm-Hansen et al. , 1993 ; Hanelt et al. , 2001 ) . In coastal saltwaters, UV radiation is strongly attenuated due to fade out organic affair and this depends mostly on the input of this stuff from the tellurian ecosystem.
Most of the surveies pertain to the consequence of UV-B radiation merely without taking into consideration, of UV-A, is a another constituent of solar UV radiation. UV-B exhibits both positive and negative effects on works photosynthesis ( Wellmann, 1983 ) , whereas UV-B activates cistron look from PSII reaction Centre proteins ( Christopher and Mullet, 1994 ) it inflicts harm to photosynthetic setup ( Joshi et al. , 1997 ; Turcsanyi and Vass, 2000 ) .
Seaweeds ( besides referred to as ‘Marine Macroalgae ‘ ) represent cardinal constituents within coastal ecosystems ( Luning, 1990 ) . They are harvested by adult male for centuries, peculiarly in Japan and China where they form a portion of the stable diet. The utilizations of seaweeds as nutrient, fresh fish and manure are good known in many states. These seaweeds are autophytic, non-vascular, benthal macroscopic algae which forms an of import constituent of the Marine populating resource. They are available mostly in shallow coastal Waterss wherever there is a substrate on which they can turn and boom. Seaweeds are marine workss because they use the light energy to bring forth saccharides from C dioxide and H2O.
Seaweeds are chlorophyll bearing workss with a works organic structure demoing no distinction into true tissues. It ne’er form true, roots, stems, foliages and so it called a thallus on fond. The thallus has no elements for the conveyance of fluids. Seaweeds exhibit a great diverseness in organisation of their organic structure. These are co-enocytic signifiers on siphonaceous signifier in which the cells are multinucleate without cross walls so that the full works consists of a diversely ramified hallow tubing.
Marine macroalgae contain more than 60 hint elements in a concentration much higher than tellurian workss. They besides contain protein, I, Br, vitamins and substances of stimulating and antibiotic nature. Seaweeds are the lone beginning for the production of agar, alginate and carrageenin. The phytochemicals are extensively used in assorted industries such as nutrient, confectionery, fabric, pharmaceutical, dairy and paper industries largely as gelling, stabilising and inspissating agents. Apart from these, biochemicals other merchandises such as Osmitrol, laminarin and fucadin are besides obtained from marine algae. New efforts are being made for testing pharmaceutically active compounds from seaweeds. Seaweeds are applied as manure in agribusiness workss, which can keep a high degree of available N in dirts. Therefore to name these marine workss ‘weeds ‘ is wrong, because they are indispensable in nature and straight valuable to worlds ( Santhi, 2004 ) .
Based on their pigmentation, morphology and anatomy, seaweeds are classified into three groups viz. Chlorophyceae ( Green algae ) , Rhodophyceae ( Red algae ) and Phaeophyceae ( Brown algae ) . As primary manufacturers these viridities, ruddy and brown algae serve a battalion of ecosystem maps. Pigments are present in the petroleum infusion of these marine macroalgae and are represented by chlorophylls and carotenoids ( Smith, 1964 ) .
Seaweeds are chlorophyll bearing workss with a works organic structure demoing no distinction into true tissues. chlorophylls in Marine algae are of three types viz. , chlorophyll-a, chlorophyll-b and chlorophyll-c. Basically chlorophyll is a big conjugated macro-cycle incorporating four convoluted nitrogen sub-cycles. The conjugated dual bonds or negatron system consequence in strong soaking up of visible radiation, which in convoluted ring construction and the interior N atom produce a rich optical spectrum and even rich supply of oxidation-reduction degrees. The chelated metal in chlorophyll is Mg2+ ion ( Santhi, 2004 ) .
Carotenoids are a category of natural fat soluble pigments by and large found in workss, algae and photosynthetic bacteriums, where they play a critical function in the photosynthetic procedure ( Joseph et al. , 2000 ) . They are normally thought of as works pigments, but besides occur widely in micro-organisms and animate beings. Among the assorted categories of natural pigments such as the anthocyanins, flavonoids, pyrroles, blood and bile pigments ; the carotenoids are the most widely dispersed and structurally diverse pigment agents. To day of the month, approximately 600 different natural carotenoids have been identified ( Latscha, 1990 and 1991 ) . Carotenoids are besides known as lipochromes, produced in nature via isoprenoid tract. Carotenoids are xanthous to orange ruddy pigments that are omnipresent in nature ( Guyomalch et al. , 2000 ) . Carotenoids besides play an of import possible function in wellness by moving as biological antioxidants, protecting cells and tissues from the detrimental effects of free groups and vest O ( Di Mascio et al. , 1989 ) .
Carotenoids are synthesized by all photosynthetic beings from bacteriums to workss where they play atleast three indispensable maps: foremost, they act as accessary light reaping pigments by absorbing visible radiation in the 450 – 570 nm parts. Second, they are of import for the assembly and stableness of some of light reaping composites. Finally they operate as photoprotectors by straight slaking both three excited chlorophylls and vest O.
Carotenoids are structurally related to retinol and b-carotene the chief beginning of vitamin A for animate beings ( Latscha, 1991 ) . Carotenoids are defined by their chemical construction. The bulk carotenoids are derived from a 40-carbon polyene concatenation, which could be considered the anchor of the molecule. This concatenation may be terminated by cyclic terminal groups ( rings ) and may be complemented with O incorporating functional groups ( Joseph et al. , 2000 ) . The hydrocarbon carotenoids are known as provitamin As, while oxygenated derived functions of these hydrocarbons are known as luteins.
The typical form of jumping individual and dual bonds in the polyene anchor of carotenoids is what allows them to absorb extra energy from other molecules, while the nature of the specific terminal groups on carotenoids may act upon their mutual opposition. The former may account for the antioxidant belongingss of biological carotenoids, while the latter may explicate the differences in the ways that single carotenoids interact with biological membranes ( Britton, 1995 ) .
The natural functions of carotenoids is color, photosynthesis and photoprotection are good established and of major biological importance. The construction of the carotenoid finally determines what possible biological maps that pigments may posses. The maps, applications and utilizations of carotenoids are due to the light absorbing belongingss of the polyene chromatophore ( Joseph et al. , 2000 ) . Carotenoids are responsible to supply bright color, serve as antioxidants and can be a beginning for vitamin A activity ( Ongand, 1992 and Britton et al. , 1995 ) . They besides play an of import function in medical every bit good as in industrial field.
The xanthous orange carotenoid pigments of workss lessening during the aging or the decease stage of workss but do non ever diminish to the point of close extinction as do the chlorophyllic pigments ( Leffingwell, 2001 ) . Carotenoids transportation most of the captive energy to12 chlorophyll-a for photosynthesis. In add-on, the carotenoids protect the chlorophyll molecules from photooxidation under strong visible radiation. The presence of carotenoids in thylakoids is usually made by the co-existence of chlorophylls. All the chlorophylls and most of the carotenoids nowadays in the thylakoid membrane are not covalently bound to protein organizing pigment protein composites ( Thornber et al. , 1979 ) .
It is good known that visible radiation is one of the of import physical factor which preponderantly influences the architecture of the photosynthetic setup. In the procedure of photosynthesis, photoautotrophic beings ( like seaweeds ) convert light energy into chemically bound energy, which is used for biomass production ; as a basic for all heterotrophic beings. Changes in irradiance and light quality can either promote photosynthesis, but can besides suppress many biological procedures, if radiation becomes inordinate, or if short wavelength radiation with high energy content, such as UV radiation, is absorbed by biomolecules. Consequently, harm to of import constituents in works metamorphosis consequences in decreased photosynthetic and general metabolic activity and therefore lead to a lessening in biomass production ( Santhi, 2004 ) .
In seaweeds, carotenoids, chlorophyll, luteins are widely distributed. Carotenoids are responsible to supply bright color, serve as antioxidants and can be beginning for vitamin A activity ( Ong and Tee, 1992 ; Britton et al. , 1995 ) . Carotenoids are responsible for many of the ruddy, orange and xanthous chromaticities of works foliages, fruit and flowers every bit good as the colors of some birds, fish and crustaceans. E.g. carotenoids color: orange coloring material of carrots and citrous fruit fruits and the pink of flamingoes and salmon ( Pfander, 1992 ) .
Carotenoids are xanthous to orange ruddy pigments that are omnipresent in nature ( Guyomarch et al. , 2000 ) . Carotenoids besides play an of import possible function in human wellness by moving as biological antioxidants, protecting cells and tissues from the detrimental effects of free groups and vest O ( Di Mascio et al. , 1989 ) .
Biological maps of carotenoids
Growth
Vitamin activity Cancer bar
Protection Biological map s Water balance
Antioxidants Immune response
The decorative and nutrient industries take advantages of the antioxidant belongingss of some carotenoids, which can lade to their inclusion into nutraceutics or drug, since some carotenoids may forestall diseases like malignant neoplastic disease or coronary artery disease, excite antibody response ( Astrong, 1997 ; Clinton, 1998 ; Johnson and Schroeder, 1995 ) .
Carotenoids have of import maps in photosynthesis, food and protection against photoxidative harm. Due to their tremendous importance within coastal ecosystems a lessening in seaweed copiousness related to environmental alteration e.g. under increased UV-irradiance. The physiological and ecological effects of present UV-B-irradiance is a stipulation in order to be able to gauge future effect of ozone depletion and increased UV-B degrees.
Solar radiation is the most of import requirement for life on Earth. In the procedure of photosynthesis, photoautotrophic beings ( like seaweeds ) convert light energy into chemically bound energy, which is used for biomass production ; as a side consequence, molecular O is generated as a footing for all heterotrophic beings. Changes in irradiance and light quality can either promote photosynthesis, but can besides suppress many biological procedures if radiation becomes inordinate ( Barber and Anderson, 1992 ) , or if short wavelength radiation with high energy content, such as UV-B radiation, is absorbed by biomolecules ( Vass, 1997 ) . Consequently, harm to of import constituents in works metamorphosis consequence in reduced photosynthetic and general metabolic activity and therefore lead to a lessening in biomass production.
Ever since the find of stratospheric ozone depletion in the Antartic in the 1970s ( Farman et al. , 1985 ) , serious concerns have arisen about the impacts of increasing UV radiation on biosphere ( Mandronich et al. , 1998 ; Bjorn et al. , 1999 ) . Ozone is preponderantly generated in the low latitudes, by photolysis of molecular O. In the stratospere, ozone molecules are capable to UV-mediated photolysis and may besides be degraded due to the reaction within catalytic rhythms with No, Cl or Br functioning as accelerators ( Langer, 1999 ) . The concentration of these compounds in the ambiance increases chiefly due to anthropogenetic emanations, therefore taking to ozone depletion.
Ultraviolet radiation includes the wavelengths below those seeable to the human oculus. Therefore spectral scope is harmonizing to the CIE definition divided into 3 wave sets: 315 – 400 nm UVA, 280 – 315 nm UVB and 190 – 280 nm UVC, which does non make the Earth ‘s surface as it is wholly absorbed on its manner through the ambiance. Due to the optical feature of ozone, it is the UVB scope, which is likely to increase at the Earth ‘s surface, as a effect of a lessening in stratospheric ozone concentration. Calculation based on the soaking up features of O3 indicate that a 10 % diminution in column ozone would ensue in an approximative 5 % addition of surface irradiance at 320 nanometers while the same diminution would be accompanied by a 100 % addition at 300 nanometer ( Frederic et al. , 1989 ) .
Biological effects of UV-B
The consequence of UV-B exposure on the biological systems are multiplex and range from the molecular to the being degree, thereby impacting growing and production and accordingly, ecosystem construction and map.
The physiological effects are besides reflected on the ultrastructural degree. UV-B radiation can take to dramatic alterations of the all right construction of chloroplast and chondriosome. Mild UV emphasis leads to a wrinkly visual aspect of the thylakoids, lms distensions and harm of the outer membranes. In the chondriosome, a puffiness of the gistal is frequently observed ( Poppe et al. , 2003 ; Holzinger et al. , 2004 ) .
On the being degree, the effects mentioned above can ensue in decreased growing and production, as shown in higher workss, seaweeds, phytoplankton and ice algae ( Caldwell, 1971 ; Worrest, 1983 ; Ekelond, 1995 ; Karentz et al. , 1991a, B ; Makarou, 1999 ; Aguilera et al. , 2000 ; Altamirano et al. , 2000a, B ) . Other effects include the damage of generative success on may even been deadly effects. Consequently, all facets mentioned may besides impact ecosystem constructions ( Holm-Hansen et al. , 1993 ; Johanson et al. , 1995 ; Caldwell et al. , 1998 ) .
CONCLUTION
Now a twenty-four hours, the Marine workss such as seaweeds, seagrasses, Rhizophora mangles and microalgae etc. , are found to be the beginning for nutrient, medical specialties, oil and other economically of import merchandises. In this context, the universe states should conserve these marine vegetation from the hurtful effects of ultraviolet radiation every bit good the International nature preservation organic structures should impart custodies to manus in order to protect the most cherished Marine vegetations and zoologies for the benefit of the future coevalss.
