Nutrients content of four tropical seaweed species from Kelapa Beach, Tuban, Indonesia and their potential as ruminant feed

Abstract

Abstract. Kustantinah, Hidayah N, Noviandi CT, Astuti A, Paradhipta DHV. 2022. Nutrients content of four tropical seaweed species from Kelapa Beach, Tuban, Indonesia and their potential as ruminant feed. Biodiversitas 23: 6191-6197. Indonesia is one of the tropical countries with the largest diversity of seaweed, but studies on identifying the nutrients content of numerous seaweed species from tropical oceans and their potential as ruminant feed have not been widely reported. This study was designed to evaluate the nutrient, macro and micromineral content of brown (Laminaria sp. and Padina australis) and red seaweed (Eucheuma cottonii and Gracilaria sp.) from Kelapa Beach, Tuban, East Java. All tests were carried out in duplicate from individual seaweed and data were analyzed descriptively by calculating the average of data obtained. The result showed that all of the seaweed species in this experiment had a high content of water (69.41-86.33%) and ash/mineral (23.42-65.63%). The brown seaweed Padina australis had the highest dry matter (30.59%) and crude protein (12.57%). The red seaweed of Gracilaria sp. had the highest ash (65.63%) and the lowest organic matter (34.37%), ether extract (0.21%), crude fiber (2.49%), nitrogen-free extract (19.95%), neutral detergent fiber (21.74%), acid detergent fiber (5.46%), and gross energy (1,083 Cal/g); however, in contrast, Eucheuma cottonii had the highest organic matter (76.58%), ether extract (2.85%), crude fiber (8.80%), nitrogen-free extract (56.38%), neutral detergent fiber (56.93%), acid detergent fiber (11.44%), and gross energy (2,911 Cal/g) but the lowest dry matter (13.67%) and crude protein (8.55%). The brown seaweed Padina australis had the highest Na (0.89%), Mg (4.90%), and Cd (3.73 ppm) contents. The red seaweed of Gracilaria sp. had the highest K (2.18%), Ca (5.80%), Fe (7,596 ppm), Mn (818 ppm), Cu (5 ppm), Zn (52 ppm), and Pb (60.38%); however, in contrast, Eucheuma cottonii had the lowest P (0.01%), K (2.02%), Ca (0.64%), Mg (1.09%), Fe (400 ppm), Mn (38 ppm), Pb (17.31 ppm), and Cd (1.53 ppm) but the highest S (0.46%). Based on this study, brown seaweed (Laminaria sp and Padina australis) and red seaweed (Eucheuma cottonii and Gracilaria sp.) from Tuban Regency, East Java, Indonesia have the potential as ruminant feed, especially as soluble carbohydrates and an organic mineral source that requires attention for heavy metals to prevent toxicity to ruminants.