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International Journal of ChemTech Research CODEN (USA): IJCRGG, ISSN: 0974-4290, ISSN(Online):2455-9555 Vol.9, No.11 pp 229-234, 2016
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Analysis of Caulerpa sp Quality Cultivated with Different Harvesting Age
Darmawati1, 2*, Andi Niartiningsih3, Rajuddin Syamsuddin3
and Jamaluddin Jompa3
1Doctoral Program of Agricultural Science, University of HasanuddinMakassar Jl. PerintisKemerdekaanKM.10 Makassar 92 045, Indonesia
2Faculty of Agriculture, University of Muhammadiyah Makassar Jl. Sultan Alauddin No. 259 Makassar 90221, Indonesia
3Faculty of Marine Science and Fishery, HasanuddinUniversity Makassar Jl. PerintisKemerdekaanKM.10 Makassar 92 045, Indonesia
Abstract : A high variability of seaweed quality might be influenced by duration of rearing (harvesting age). This study aimed to investigate the appropriate harvesting age for the best quality, that be conducted on Lagurudav illage’s waters, Takalar regency(05º26'07.9"S and 119º22'29.9"W) by using floating monoline method. A 50 grams of each seed’s initial weight was set with 30 cm space each seed, kept submerged at the depth of 50cm above seawater surface. The quality of Caulerpa sp measured at different harvesting age includes: moisture, protein, fat, crude fiber, carbohydrate and ash content. The quality Caulerpa sp and water quality were analyzed descriptively. The quality of Caulerpa sp (protein, crude fiber, carbohydrate, ash content) was observed increase in line with the increase of harvesting age. Several observed nutrient contents, such as protein (13.80%), crude fiber (15.72%), NFE (10.75%), and ash content (29.01%), were quite high. The moisture was monitored in the range of 42.98%-48.77%. the fat content was fluctuated in the range of 0.17%-0.29%. Water quality parameters, such as light intensity, temperature, pH, salinity, turbidity, nitrate and phosphate, were observed in the ideal condition for the growth of Caulerpa sp.
Keywords : seaweed Caulerpa sp, quality, harvesting age.
Introduction
Caulerpa sp, one of green seaweed species with many potential benefits for human, begins to be utilized as a food ingredient, being freshly raw-consumed or as a vegetable. It has been proven to have high nutritional contents –plant-based protein, carbohydrates, minerals, vitamins5,19 and polyphenols21.Besides, the edible alga contains Insoluble Dietary Fiber or IDF12,generally composed of cellulose and hemicellulose, pharmaceutical, and cosmetic industries23,26.
Many benefits of Caulerpa sp make it begins to be exploited, generally obtained from nature that depends on natural conditions and seasons. Therefore, the effort to increase production is important to fulfill the ever-increasing requirement. Aquaculture is expected to fulfill the requirement, obtain maximum and continuous production, and well-organized supply, either quantity or quality.
The explained condition, nowa days, trigs to the production-based study which tend to the importance for good quality through aquaculture. The quality produced by seaweed is greatly environment-influenced,
might be geared by location and duration of rearing which is associated with the availability of nutrients. Seaweed growth is entirely dependent on the availability of nutrients and environmental conditions as aquaculture. In addition, the duration of rearing could affect to the nutrient content, both quantity and quality13. It can be understood that the nutritional content of seaweed is a product of photosynthesis that is very dependent on the duration, direct on the nutrient accumulation in thallus. Therefore, the nutrient content is highly depended by the duration of rearing. The harvesting age should be well-noted to ensure the quality seaweed cultivated for resulting the maximum quality.
Based on the above, it is necessary to measure the quality of the different harvest time so it can be determined when Caulerpa must be harvested with the best quality.
Materials and Methods
Seed of Caulerpa sp.
The fresh seeds, identified by characteristic green color, fresh appearance of branch and stolon, were obtained from the waters around the Spermonde islands, Makassar. The young seed, characterized by white/clear color, was avoided18.
Preparation
The study took a place on the waters of village Laguruda, Takalar, considering of lots of seaweed farming activities. The initial stages were preparation of aquaculture floating raft sized 3x2m2 which consist of beams, bamboos, PE plastic rope (Ǿ 2.7 and 10mm), icestrap, net, and anchor.
Cultivation of Caulerpa sp.
The study employed the floating monoline method, performing to adjust the sea level change. The floating method made it fixed on the sea surface. Seeds of seaweed, initially weighted 50 grams each, were set 30cm every clump of treatments, planted at 50cm depth-from-sea surface. Seaweed were reared for 42 days, and sampled with an interval of 14 days (0, 14, 28, and 42 days after planting). Samples were weighed and performed for proximate analysis to determine nutrient levels (seaweed quality).
Quality Analysis of Caulerpa sp.
Quality analysis of Caulerpa sp was performed by using proximate analysis, which include: content of protein, moisture, ash, fat, crude fiber and carbohydrate.
Protein content2,24 :
where: a = ml NaOH for the blank titration, b = ml titration NaOH for sample titration, N = normality of NaOH, W = weight of sample (g)
Moisture content1 :
Description: W1 = initial sample weight, W2 = final sample weight
Ash content2:
Description: A = cup + dry sample (g), B = empty cup (g), C = sample’s cup (g)
Fat content2 :
Crude fiber content2 :
Where: a = weight of fiber residue in the filter paper (grams), b = weight of dry filter paper (grams), c = initial weight of the sample (gram)
Carbohydrate content2 :
Carbohydrate content (%dw) = 100% - (A+B+C+D+E)
Where: A = moisture content, B = ash content, C = fat content, D = protein content, E = crude fiber content.
Water Quality Analysis
Water quality parameter measurements were conducted every week until the end of rearing period, include: light intensity, temperature, pH, salinity, turbidity, nitrates and phosphates.
Data Analysis
Data of Caulerpa sp quality were analyzed descriptively, while water quality data were analyzed descriptively according to the ideal condition for the growth of Caulerpa sp.
Results and Discussion
Quality of Caulerpa sp
Data of Caulerpa sp quality during the study were presented by the proximate analysis result, showed in Table 1 below.
Table 1. Quality of Caulerpa sp during the study
Proximate Analysis |
Age of harvesting |
|||
0DAP |
14DAP |
28DAP |
42DAP |
|
Moisture (%) |
46.09 |
48.77 |
43.65 |
42.98 |
Protein (%) |
6.30 |
6.63 |
9.60 |
13.80 |
Crude fiber (%) |
8.75 |
9.00 |
10.83 |
15.72 |
Fat (%) |
0.17 |
0.29 |
0.13 |
0.17 |
NFE (%) |
6.20 |
6.29 |
7.58 |
10.75 |
Ash (%) |
27.86 |
28.01 |
28.56 |
29.01 |
*) DAP: Day(s) After Planting
The result (indicated in Table 1) shows that harvesting age affects the quality of Caulerpa sp. Quality of Caulerpa sp, described by protein, crude fiber, fat, carbohydrate and ash content, increased in line with the increase of the harvesting age. This finding is consistent with8,16, stated that the chemical content of seaweed is very varied, whose influence are species and harvesting age.
Moisture content of Caulerpa sp.was observed in the range of 42.98%-48.77%. The highest value was obtained at 14 days of harvesting age, 48.77%. At 28 days of harvesting age, it began to decline, then got the lowest at 42 days of harvesting age, to 42.98%. The low moisture at 42 days might be caused by the late-harvesting, makes polysaccharide in cells growing up and reduce the moisture. The high moisture of seaweed makes the soften-texture, resulting in the ease-to-consume as a fresh vegetable.
An increase of protein content of Caulerpa sp was found linearly with an increase of harvesting age with a range of 6.30%-13.80%. The highest was observed at 28 days and 42 days of harvesting age, respectively 9.60% and 13.80%. This finding is in accordance with6, stated that the wet weight of green seaweed contains 6-20% protein.While17the protein content of Caulerpaspranged10-13%. The protein content of green seaweed is higher than red seaweed and brown seaweed4. Protein content of seaweed is also influenced by the availability of nitrogen in water8.The algal cell walls are also rich in proteins, which are embedded in the matrix polysaccharide phase26.
Crude fiber content was observed to increase with an increase of harvesting age. Started at 8.75% in the beginning, it then increased to 15.72% after 42 days. This might be due to high polysaccharide content of seaweed when the harvesting age increased. Polysaccharides of seaweed are hardly digestedby human’s digestion system, make it suitable as a fiber source, which means it can stimulate the fiber intake. Total crude fiber is an amount of dietary fiber and functional fiber6,17.
Fat content of this study was observed to be fluctuated, ranged 0.17-0.29%. This is in accordance with6,20, that seaweed contains a low fat content, ranged 1-5%. Furthermore6,22,stated that the seaweed is poor in fat, generally less than 4%.. Fat content of seaweed are mostly composed by poly unsaturated fatty acids, generally essential for humans and animals16,16,27.
Nitrogen-Free Extract (NFE) content also increased with the increase of harvesting age, dramatically at 42 days, overall ranged 6.20%-10.75%. Seaweeds are generally storing food in the form of carbohydrates, especially polysaccharides19. The building compound of carbohydrates is the further product of photosynthesis, the content depends on the photosynthesis rate and accumulation time of assimilate in thallus cells. It is mostly in the form of fiber, an undigested by human digestive enzymes, that plays a small role of calories intake and makes it suitable for a diet food20..Furthermore, 6stated that xylan and ulvan are easy-to-find polysaccharides of green algae and easy-to-digest by intestinal bacteria. The cell wall of Caulerpa is described as a branched polymer containing 3-linked galactose, terminal-and 4-linked xylose, as well as 4-and 3,4-linked arabinose residues. Sulfate groups, when present, are linked to C-3 of 4-linked arabinose and C-6 of 3-linked galactose units. No pyruvic acid has been reported3.
Ash content in this study increased with the increase of harvesting age but not significant. This is due to the increase of nutrients level in line with the harvesting age. Ash is an essential component in a dietary, determining the mineral level. Ash content in seaweed consists of macro-minerals and trace elements6.Absorption of minerals in seaweed was carried through whole surface of thallus, making it more effective. The amount of mineral absorbed influences of ash content in seaweed tissues.
Photosynthesis affects the quality of seaweed, the longer the harvesting age the longer it lasts, consequently affected on the high nutritional content of seaweed that becomes higher when harvested at 42 days. Quality of Caulerpa sp obtained in this study is higher than25from ManokwariArowicoastlineand7from Tongkeina waters, Manado.
This study indicates the increase on quality of Caulerpa sp until42 days of harvesting age. However, 5argued that the growth rate for various rearing methods of Caulerpa sp began to decline when the rearing age reach 5 weeks (35 days). Quality of Caulerpa sp at harvesting age of 6 weeks (42 days) was higher than 42 days. It could be used as a basis for determining the harvesting age of Caulerpa sp. to obtain the best quality.
Several water quality parameters, such as temperature, salinity, pH, and CO2 were observed in the ideal condition for Caulerpa sp. The nitrate level was relatively low, ranged 0.01-2.6 ppm, but still within the limits of seaweedviability10,14that ranged 0.9-3.5 ppm. The phosphate level was also low (0,16-0.62 ppm) but still possible to support the survival of Caulerpa. Nitrogen and phosphorus are two essential nutrients for the growth of algae. Nutrients are needed for the growth of seaweed so that nutrients must be in accordance with the needs of seaweed. Nutrient deficiencies will inhibit the growth of seaweed while the excess nutrients will affect the growth of seaweed11.
Conclusion
Harvesting age affects the quality of Caulerpa sp. Quality of Caulerpa sp. (contains the content of protein, crude fiber, carbohydrate, and ash) increases in line with the increase of harvesting age. The highest
water content was obtained at the harvesting age of 14 days, while the lowest at 42 days. Fat content was fluctuated. Water quality parameters (light intensity, temperature, pH, salinity, turbidity, nitrate and phosphate) were still in the ideal condition for Caulerpa sp.
We would like to suggest that the Caulerpa sp. harvesting should be done after 42 days of rearing. Research on the exploration and processing needs to be developed considering the high potential of Caulerpa sp. as an food ingredient and nutrient source.
References
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