Effect of Global Warming Scenarios on Carotenoid Pigments Gracilaria changii

The phenomenon of global warming is an increase in the earth's temperature due to the greenhouse effect where 50% of the main contributors to the greenhouse effect are carbon dioxide (CO2). Carbon dioxide is one of the ingredients needed for photosynthesis. Photosynthesis is carried out by plants that have chloroplasts. Plants in the waters are Seaweed. Gracilaria changii is a type of red seaweed (Rhodophyceae). The dominant pigment from Gracilaria changii is carotenoids. Carotenoid serves as a light energy absorbent for photosynthesis and serves to protect chlorophyll from light damage. Seeing the important role of carotenoids in Gracilaria changii so that this study aims to determine the effect of increasing temperature and carbon dioxide on carotenoid pigments. Research on the scenario of global warming in this region was first carried out on a laboratory scale, many previous studies were carried out in the cultivation area. This study was conducted for 40 days, seaweed that has been cleaned is put into an aquarium and given an injection of CO2. We were exposed to present-day control seawater (400 ppm pCO2 ) and seawater treated with CO2 to simulate ocean conditions predicted for the next 50–100 years (700 ppm, 1000 ppm, and 1300 ppm) and temperature treatment (30 oC, 32 oC, 34 oC). The research design applied in this study is a Completely Randomized Design consisting of nine treatments with three replications. Data analysis used is Analysis of Variance (ANOVA) continued by Post hoc Test. The results obtained from this study there were significant differences (P


I. INTRODUCTION
Global warming is an increase in earth temperature due to the greenhouse effect, which is 50% caused by Carbon dioxide (CO2) (Prasad et al. 2017;Forster, P., et al. 2007). So that this phenomenon has a major impact on living things and the environment (Fabry et al. 2008). The high CO2 in the atmosphere will diffuse into the seawaters and cause chemical changes so that it makes the ocean acidic (Auerbachu et al. 1997). The absorption of carbon dioxide is indicated to cause a reduction of 0.1 units of sea surface pH which is equivalent to a 30% increase in the concentration of hydrogen ions in the sea (Caldeira, et.al 2005) so that it can cause ocean acidification (Doney et al. 2009). Carbon dioxide is one of the materials in the process of photosynthesis by plants that have chloroplasts (Joseph et al, 1982; Richter 2018). One of the plants that live in waters is seaweed. Based on the pigment seaweed is divided into 3 major classes namely red seaweed (Rodophyceae), green seaweed (Chlorophyceae), and brown seaweed (Phaeophyceae) (Aryee et al. 2018). Gracilaria changii is a type of red seaweed (Rhodophyceae) with carotenoids as the dominant pigment (Chan & Matanjun, 2016). Seaweed is resistant to environmental conditions compared to other types of grass (Wei et al. 2015). The colors produced by carotenoids range from pale yellow, bright orange, to deep red, depending on the chemical structure of each. Carotenoid functions as an absorbent light energy for photosynthesis and functions to protect chlorophyll from O2 damage caused by oxidation when the radiation level is high (Richter 2018). Based on the fact that there is an association between carotenoids and CO2, this study was conducted to determine the effect of increasing carbon dioxide and temperature on the amount of carotenoid pigments. Research on the scenario of global warming in this region was first carried out on a laboratory scale, many previous studies were carried out in the cultivation area.

II. METHODS AND MATERIAL
Gracilariia changii samples were obtained from cultivation sites in Ujung Baji Village, Takalar Regency, Indonesia.  The research sample was dried using an oven with a temperature of 50 o C. Then take 2 grams and add 10 ml acetone, let stand for a day in a dark room. After that, absorbance is measured using a spectrophotometer. Data analysis used is Analysis of Variance (ANOVA) followed by Post hoc Test.

III. RESULTS AND DISCUSSION
Based on statistical analysis with ANOVA the initial carotenoid pigment content of 0.24 ± 0.51 μg / g showed a significant (P <0.05) difference in the content of late carotenoid pigments. At the end of the study the highest carotenoid pigment was found in the injection treatment of pCO2 700 ppm with a temperature of 34 o C having a pigment content of 2.05 ± 1.32 μg / g followed by a temperature of 32 o C with a pigment content of 1.66 ± 1.28 μg / g and temperature 30 o C has a pigment content of 1.66 ± 1.43 μg / g. The carotenoid pigment content at injection of pCO2 1000 ppm with a temperature of 32 o C was 1.34 ± 1.04 μg / g whereas at 34 o C the carotenoid pigment content was 1.26 ± 1.24 μg / g and at a temperature of 30 o C the carotenoid pigment content amounting to 1.22 ± 0.79 μg / g. pCO2 1300 ppm at 30 o C has a pigment content of 0.94 ± 0.91 μg / g, the pigment content at 34 o C is 0.91 ± 0.86 μg / g, and at 32 o C has a pigment content of 0.73 ± 0.86 μg / g. The carotenoid pigment content at the end of the study showed that injection of pCO2 700 ppm had a significant difference (p <0.05) for injection of pCO2 1000 ppm and injection of pCO2 1300 ppm. Variations in carotenoid pigment content in this research experiment are shown in Figure 2.

Fig.2: Carotenoid pigments in carbon sequestration treatment
This study showed an increase in the amount of carotenoid pigment Gracilaria changii after being given the addition of CO2 and temperature. During the experiment, the control experienced an increase in pigment levels when compared with the initial levels of the sample before the experiment was carried out. The level of carotenoid pigment increases with the addition of pCO2 700 ppm and then decreases slightly with the addition of 1000 ppm pCO2. The carotenoid pigment content at the addition of pCO2 1300 ppm has decreased and returned to the same as the control but the carotenoid pigment levels have all increased when compared to the initial pigment of the study. Carotenoid pigments are one of the pigments found in chloroplasts which play a role in photosynthesis (Salisbury, F. B. & Cleon, W. R., -). Photosynthesis is the process of compiling organic compounds from CO2 and Water that require light (Loveless, A.R., 1991). Light is very closely related to chloroplasts because light has the nature of wavelengths and properties of particles which are energy. The chloroplast pigment absorbs more than 90% of the purple and blue wavelengths that hit it and is almost as big as the percentage of orange and red wavelengths (Loveless, A.R., 1991).
Addition of carbon dioxide concentration to 700 ppm and supported by photoperiod 24 L caused an increase in photosynthesis (Loveless, A.R., 1991). This is because Gracilaria changii will take more carbon dioxide because the Rubisco enzyme that functions to hold CO2 becomes active in the presence of light (Caemmere, S Von; G.D. 1981; Salisbury, F. B. & Cleon, W. R., -). The temperature of 34 o C is the optimum temperature in the tropics for increasing the speed of photosynthesis. Temperatures above about 35 o C cause temporary damage or permanent damage to the protoplasm, which causes a decrease in the speed of photosynthesis (Loveless, A.R., 1991). At the end of the study the addition of pCO2 of 1000 ppm and pCO2 of 1300 ppm showed an increase in carotenoid pigment content when compared with the levels of carotenoid pigments at the beginning of the study, but rather decreased compared to the addition of pCO2 700 ppm due to the high addition of carbon dioxide can affect pH levels in water. Low pH in water makes work function Rubisco enzymes found in inactive chloroplasts and decreases in pH greatly influence the transfer of electrons from polypeptides with molecular weights around 33kDa to P680 (Conjeaud 1980 CONCLUSIONS The conclusion of this study: 1. shows effect of the scenario of global warming on carotenoid pigment. 2. Treatment of carbon dioxide injection and temperature differences indicate an increase in amount of carotenoid pigments and the highest increase occurs in the injection of carbon dioxide 700 ppm with a pigment content of 2.05 ± 1.32 μg / g.