The objectives of this study were to evaluate the effect of different dietary levels of tropical marine brown macroalgae, Sargassum cristaefolium meal (SCM) on growth performance and feed utilization ...efficiency of juvenile white shrimp, Litopenaeus vannamei (mean initial weight 2.65±0.1 g). The algae were collected from Bandengan Coast, Jepara, Indonesia. The study used a completely randomized design with 5 treatments of dietary different S. cristaefolium meal levels (0, 10, 20, 30, and 40 g algae meal/kg feed) in triplicates. The results showed that the different levels of dietary SCM did not significantly affect (P>0.05) average daily growth (ADG;.204-224 mg/day) and survival (80-97%) of the shrimp after a 42-day feeding period. However, the test diets significantly affected (P<0.05) feed intake (FI), feed conversion ratio (FCR), and protein efficiency ratio (PER). Better FCR (2.13) and PER (1.34) was found by the diet with 2% SCM compared to the control diet (no SCM) (FCR 3.42 and PER 0.81). This finding indicates that the supplement of dietary 2% SCM (20 g/kg feed) can increase the feed utilization efficiency up to 62% or reduce the FCR up to 38% without any adverse in growth performance.
Macroalgae is one of renewable marine biomass feedstocks for substituting land biomass. With the use of anaerobic digestion (AD) technology, macroalgae has been greatly acknowledged for bioenergy ...production resources, including biogas. On the other hand, Batik wastewater contains chemical dyes and organic pollutants, which potentially cause environmental pollution if disposed without a proper treatment. The aims of this research were to evaluate the potential of biogas and methane production using different ratio of Batik wastewater: macroalgae (i.e. Gracilaria verrucosa fresh and dried samples) and to estimate the electrical potential generated. A biochemical methane potential (BMP) test was carried out at temperature of 37 °C for 28 days under batch condition. The results indicated that digesting Batik wastewater alone, without dilution, showed an inhibition process as indicated by a negative net biogas and methane production as well as the specific methane production (SMP). Co-digesting Batik wastewater with fresh marine G. verrucosa samples at ratio of 50:50 cannot produce a high amount of biogas or methane. All samples showed a similar biogas or methane volume compared to that of the inoculum sample. This indicated that an inhibition was occurred limiting the microbial consortia in inoculum to breakdown the organic matter in the feedstock material. This could be due to the salinity of macroalgae and the high organic pollutant concentration in Batik wastewater. However, co-digestion of Batik wastewater with dried marine G. verrucosa produced higher SMP. Further alternative options to enhance to utilisation of Batik wastewater are needed.
Coral reefs in Kapoposang Islands have been degraded for years due to environmental pressures and human activities. After designated as marine protected area (MPA), coral reefs conditions (e.g. ...living coral coverage - both hard and soft corals) were monitored regularly since 2015 by several agencies. This study aims to evaluate the effectiveness of MPA management in Kapoposang by analyzing changes of coral reef coverage in its two core zones. The survey was conducted in July 2019 using Line Intercept Transect (LIT), video transect, and satellite imagery analysis, then compared to data from the previous assessment. Results of recent survey, i.e.: living coral reefs coverage ranged from 46.73% - 73.08%; 21 genera found with 10 dominant genera, which Porites sp., is a resistant coral genus and the most dominant genus in Kapoposang MPA; the highest coral recruitment was found in Suranti island at a depth of 10 meters, while the lowest is in Papandangan island; several genera in the form of recruitment (e.g. Acropora sp., Goniopora sp., Fungia sp., Favona sp., and Porites sp.); percentage of macroalgae is 2.95% of total coral reef substrate cover; the most densely macroalgae coverage is found in Suranti, while the lowest is in Kapoposang island.
The bioremoval potential of brown marine macroalga Padina pavonia for the uranium ions from aqueous solutions was studied under different experimental conditions with respect to the influences of pH, ...initial uranyl concentration, contact time, biomass dosage, and temperature of solution. Langmuir, Freundlich, Dubinin–Radushkevich, Flory–Huggins, and Brunauer–Emmett–Teller models were applied to describe the biosorption isotherm of uranium ions by P. pavonia biomass. Thermodynamic parameters such as biosorption enthalpy, entropy and free energy transition have been calculated. Biosorption from simulated artificial wastewater by P. pavonia was also investigated. Bioremoval efficiency and distribution coefficient of biomass, under the optimum biosorption conditions were calculated as 98 ± 1% and 5257 ± 312 mL/g, respectively. The Dubinin–Radushkevich isotherm model better fits the biosorption data and the experimental biosorption capacity was found to be 162 mg UO22+/g.
Brown marine macroalga Padina pavonia was used as a novel biosorbent for uranium removal, which has chemical and radiological toxicity. Five isotherm models, thermodynamics and different experimental conditions were studied by batch technique. Several mechanisms are simultaneously active in this process. P. pavonia biomass appeared to be an effective and alternative technique.
Environmental pollution, caused by the introduction of hazardous substances such as heavy metals into coastal waters, affects not only the condition of the waters but also the source of food that ...will be contaminated by hazardous metals, one of them is mercury (Hg). Mercury is toxic metal which could cause damage to the human body in certain threshold amounts. The aim of this study was to determin the content of mercury in several species of algae from Burung and Tikus Island, Jakarta. This study was using a descriptive method. The samples were collected from Burung and Tikus Island by simple rundown sampling. Mercury level was measured by NIC3000 mercury analyzer tool. The results showed that none of the mercury levels have passed 0.5 mg/kg (the safety standart level of mercury by SNI (Indonesian National Standard)7387 in 2019) mangrove. From tikus Island had lower total mercury than the ones from Burung Island. Burung Island is located near Pari Island which is a residential area, where pollution is more likely to occur.
The present article reports a green and cost effective route for the synthesis of gold nanoparticles (AuNPs) using aqueous extract of marine macroalgae Padina Tetrastromatica. The biosynthesized ...AuNPs were characterized using UV-Visible spectroscopy, XRD, TEM, SAED, EDAX and FTIR techniques. The prepared AuNPs were found to be more or less spherical with an average size of 11.43nm.They were crystalline in nature, and showed a surface plasmon resonance peak at 532 nm.The biosynthesized AuNPs were used as nanocatalyst in the reduction of anthropogenic organic pollutant, 4-nitrophenol to beneficial 4-aminophenol using NaBH4, which followed a pseudo-first-order kinetics
In global world, increasing needs of energy is parallel to the increase of population. The limitation of land availability and change of land use has turning the focus into marine biomass, especially ...macroalgae, as renewable energy feedstocks. Indonesia is one of the biggest countries producing marine macroalgae. The aim of this research was to evaluate the impact of washing pre-treatment on the characteristics of macroalgae and its biodegradability in anaerobic digestion process. In this study, a biochemical methane potential (BMP) test was carried out using fresh macroalgae, specifically Gracilaria verrucosa. The ratio of inoculum to substrate was 6:1 with operation temperature of 37 °C and incubated for 28 days. Prior the BMP test, the G. verrucosa samples were washed with flowing water for 10 minutes. The findings confirmed for washing pre-treatment was significantly enhance cumulative biogas and methane production by more than 50%. The specific methane potential (SMP) of washed G. verrucosa increased by six-fold, with the value of 0.108 m3 CH4 / kg VS. In this case, reduction of salinity concentration after washing may play an important role in increasing the anaerobic degradability. It was estimated that a high electricity potential is generated from anaerobic digestion of G. verrucosa after washing pre-treatment.
The effect of dissolved organic matter (DOM) and oil on the removal of the water-soluble compounds benzene, toluene, ethylbenzene, and xylene isomers (BTEX) by two low-cost biosorbents
Macrocystis ...pyrifera
and
Ulva expansa
) was evaluated. DOM decreased the adsorption capacity of toluene, ethylbenzene, and xylenes of the two biosorbents. In contrast, the removal of benzene increased under the same conditions in single and multi-solute systems: this effect was dominant in
U. expansa
biomass treatments. In the presence of DOM and oil in solutions, the removal of BTEX notoriously increased, being oil that contributed the most. Solubility and hydrophobicity of pollutants played a key role in the adsorption process. The attractions between BTEX molecules and biosorbents were governed by π–π and hydrophobic interactions. Affinities of biosorbents for BTEX were mainly in the order of X > E > T > B. The Langmuir and Sips equations adjusted the adsorption isotherms for BTEX biosorption in deionized and natural water samples, but in the case of oily systems, the Freundlich equation seemed to have a better fit. The biosorption processes followed a pseudo-second-order rate in all the cases.
Marine macroalgae (seaweeds) as one of important groups of biopolymers play an important role in human life. Biopolymers have been studied regarding their film-forming properties to produce edible ...films intended as food packaging and active ingredient carriers. Edible film, a thin layer or which is an integral part of food and can be eaten together with, have been used to avoid food quality deterioration due to physico-chemical changes, texture changes, or chemical reactions. Film-forming materials can be utilized individually or as mixed composite blends. Proteins and polysaccharides used for their mechanical and structural properties, and hydrophobic substances (lipids, essential oils, and emulsifiers) to provide good moisture barrier properties. In addition, bioactive substances from marine natural products, including seaweeds, have been explored for being used in the fields of medicine, food science, pharmaceutical science, biochemistry, and glycobiology. Among them, lectins or carbohydrate-binding proteins from seaweeds have recently been remarked. Lectins (hemagglutinins) are widely distributed in nature and also good candidates in such prospecting of seaweeds. They are useful as convenient tools to discriminate differences in carbohydrate structures and reveal various biological activities through binding and interacting to carbohydrates, suggesting that they are promising candidates for medicinal and clinical application.