The brown macroalgae Sargassum has been reported for its anti-UV and photoprotective potential for industrial applications. This study evaluated the melanin inhibition activity of Sargassum cristaefolium (SCE) ethanol extract. Melanogenesis inhibition by SCE was assessed in vitro with B16-F10 melanoma cell models and in silico against melanin regulatory proteins Tyrosinase (TYR) and Melanocortin 1 Receptor (MC1R). The regulatory properties evaluated were the melanin content, intracellular tyrosinase activity and cellular antioxidant activities. In addition, the bioactive compounds detected in SCE were subjected to molecular docking against TYR and MC1R. Based on the results, 150 µg/mL SCE effectively inhibited the production of melanin content and intracellular tyrosinase activity. Cellular tyrosinase activity was reduced by SCE-treated cells in a concentration-dependent manner. The results were comparable to the standard tyrosinase inhibitor kojic acid. In addition, SCE effectively decreased the intracellular reactive oxygen species (ROS) levels in B16-F10 cells. The antioxidant properties may also contribute to the inhibition of melanogenesis. In addition, LCMS UHPLC-HR-ESI-MS profiling detected 33 major compounds. The results based on in silico study revealed that the bioactive compound putative kaurenoic acid showed a strong binding affinity against TYR (−6.5 kcal/mol) and MC1R (−8.6 kcal/mol). However, further molecular analyses are needed to confirm the mechanism of SCE on melanin inhibition. Nevertheless, SCE is proposed as an anti-melanogenic and antioxidant agent, which could be further developed into cosmetic skin care products.

The vulnerability of less developed regions is exacerbated by a lack of information to inform appropriate adaptation planning. We addressed this challenge in the islands of Lombok and Sumbawa (Nusa Tenggara Barat Province, Indonesia) by combining multiple sources of knowledge to develop a typology of natural resource use by communities of the province. This enabled an assessment of future impacts of drivers of change such as population growth and climate change. The typology was developed by cluster analysis of an inventory of the use of ecosystem goods and services (EGS) by the 105 rural subdistricts in the province. The data were largely elicited from expert knowledge, augmented by a rapid rural appraisal of communities’ marine resource use in Sumbawa. Exploratory analysis of existing secondary data on livelihoods and land use provided context and skeleton data, which were developed further by experts. Overall, 82 EGS were identified from nine terrestrial, coastal, marine and freshwater habitats. EGS included livestock, cropping, forestry, wildlife hunting, fishing, aquaculture, mining, water (for drinking and agriculture) and tourism. The typology comprised seven types that captured 42% of the variation in the data matrix. The types were moderately spatially aggregated and showed some congruence with administrative (district) boundaries. We discuss the implications of the results for planning livelihood adaptation strategies, and out-scaling these among subdistricts of matching types

This study presents a LoRaWAN-based IoT framework for robust data aggregation in Sargassum sp. cultivation, integrating multi-sensor monitoring and Kalman filter-based data enhancement. The system employs water quality sensors—including temperature, salinity, light intensity, dissolved oxygen, total dissolved solids, and pH—deployed in 6 out of 14 cultivation containers. Sensor data are transmitted via LoRaWAN to The Things Network (TTN) and processed through an MQTT-based pipeline in Node-RED before visualization in ThingSpeak. The Kalman filter is applied to improve data accuracy and detect faulty sensor readings, ensuring reliable aggregation of environmental parameters. Experimental results demonstrate that this approach effectively maintains optimal cultivation conditions, reducing ecological risks such as eutrophication and improving Sargassum sp. growth monitoring. Findings indicate that balanced light intensity plays a crucial role in photosynthesis, with optimally exposed containers exhibiting the highest survival rates and biomass. However, nutrient supplementation showed limited impact due to uneven distribution, highlighting the need for improved delivery systems. By combining real-time monitoring with advanced data processing, this framework enhances decision-making in sustainable aquaculture, demonstrating the potential of LoRaWAN and Kalman filter-based methodologies for environmental monitoring and resource management.

alvarezii is a superior product of Indonesian fisheries, producing carrageenan which is used as a food, cosmetic, and medicinal ingredient. K. striatus is a carrageenan-producing red alga that began to be cultivated in the Ekas waters of East Lombok in 2023. K. striatus is more resistant to epiphytes and sudden climate change. The purpose of this study was to analyze the growth of Kappaphycus alvarezii and Kappaphycus striatus. The research was conducted in Ekas Bay, Jerowaru District, East Lombok Regency. The research was conducted from November 8, 2023, to January 8, 2024. This research used an experimental method with T-test analysis. Treatments in this research are the cultivation of K. alvarezii and K. striatus. Cultivation was carried out at Ekas Bay. Analysis of seaweed carrageenan was carried out in the Laboratory of Fish Production and Reproduction, Aquaculture Study Program, Faculty of Agriculture, Mataram University. The result of this research is K. striatus has a higher absolute weight of 154 g compared to K. alvarezii seaweed which is 72 g. The specific growth rate K. striatus higher at 2,98 % / day compared to K. alvarezii is 1, 98 % / day. The yield of carrageenan of K. alvarezii is 1,95% and K. striatus 0,88%. Antioxidant of K. alvarezii is 5,46 % and K. striatus is 7,42%. Chlorophyll K. alvarezii is 5,77 mg/l and K. striatus is 3,51 mg/l. The conclusion of this study is the growth of K. striatus is faster than K. alvarezii.

The potential area of Lombok seaweed cultivation is 5490 Ha. The area utilized is 2039.63 Ha. The purpose of this paper is to review the diversity, cultivation activities, production and potential of seaweed to be developed, specifically focusing on aspects of cultivation and production on the island of Lombok, Indonesia. Macroalgae that have been cultivated on Lombok are Kappaphycus alvarezii morphotype brown and green and Gracilaria verucosa. The decline and the amount of uncertainty in production were caused by several problems in seaweed cultivation, weather changes, limited capital for production and decreased quality of seaweed seeds. The species that have the potential to be developed are Sargassum aquifolium, Caulerpa sp., Ulva sp., Eucheuma spinosum, and Gelidium sp. Development Locations are located throughout the waters in the shape of a bay and are by the stipulated water utilization spatial plan. Developing seaweed aqua tourism and institutional arrangements related to seaweed production is necessary.

Abstrak: Pertumbuhan Kappaphycus alvaerzii dipengaruhi oleh jumlah klorofil-a, fioeritrin serta faktor kualitas lingkungan perairan. Penelitian ini bertujuan untuk mengetahui pengaruh jarak tanam yang berbeda terhadap kandungan klorofil-a dan fikoeritrin pada Kappaphycus alvarezii hasil kultur jaringan yang dibudidayakan pada patok dasar. Penelitian ini dilakukan di Perairan Pantai Siwak Desa Gerupuk Kecamatan Sengkol Kabupaten Lombok tengah. Budidaya Kappaphycus alvarezii dilakukan selama tiga puluh hari yaitu pada tanggal 10 Maret sampai dengan 9 April 2020 dengan menggunakan metode patok dasar. Rancangan penelitian yang digunakan adalah Rancangan acak lengkap dengan empat perlakuan yaitu perlakuan A (jarak tanam 10 cm), B (jarak tanam 15 cm), C (jarak tanam 20 cm), D (jarak tanam 25 cm sebagai kontrol). Bibit Kappaphycus alvarezii yang digunakan adalah hasil kultur jaringan yang telah diadaptasikan di pantai. Pengukuran klorofil-a dan fikoeretrin dilakukan dengan menggunakan spektrofotometri dan selanjutnya data dianalisa secara statistik. Hasil penelitian ini mendapatkan bahwa jarak tanam 25 cm (kontrol) menghasilkan kandungan klorofil-a tertinggi yaitu 5,4986 mg/l dengan kandungan fikoeritrin 0,0049 mg/l. Kandungan fikoeritrin tertinggi adalah jarak tanam 10 cm yaitu 0,0057 mg/l dengan kandungan klorofil-a sebanyak 4,7662 mg/l. Jarak tanam 25 cm dapat meningkatkan kandungan klorofil-a yang lebih baik karena dengan jarak tanam tersebut memberikan ruang bagi semua bagian thallus rumput laut K. alvarezii untuk bisa menerima cahaya matahari yang cukup dan sesuai untuk kebutuhannya. Jarak tanam 10 cm memberikan kandungan fikoeritrin yang tertinggi, yaitu 0,0057 mg/l karena terlalu rapatnya jarak ini menyebabkan semakin banyak terbentuknya naungan sehingga mengurangi intensitas cahaya yang masuk ke dalam dinding sel rumput laut. Pada bagian thallus yang sedikit atau tidak menerima cahaya matahari ini diduga terjadi pembentukan fikoeritrin yang lebih banyak sebagai bentuk adaptasi thallus rumput laut pada kondisi tidak mendapatkan cahaya matahari yang optimal. Kesimpulan penelitian ini adalah jarak tanam mempengaruhi kandungan klorofil-a dan fikoeritrin. Jarak tanam yang ideal adalah 25 cm untuk menghasilkan kandungan klorofila-a yang optimum untuk mendukung pertumbuhan. Kata kunci: Fotosintesis, cahaya matahari, talus, pertumbuhan, unsur hara. Abstract: The growth of Kappaphycus alvarezii is influenced by the amount of chlorophyll-a, phycoerythrin and the quality factors of the aquatic environment. This study aims to determine the effect of different plant spacing on the content of chlorophyll-a and phycoerythrin on Kappaphycus alvarezii tissue culture results that are cultivated on the bottom-off method. This research was conducted in the waters of Siwak Beach, Gerupuk Village, Sengkol District, Central Lombok Regency. Kappaphycus alvarezii cultivation is conducted for thirty days, from March 10 to April 9, 2020, using the bottom-off method. The study design used was a completely randomized design with four treatments, namely treatment A (10 cm spacing), B (15 cm spacing), C (20 cm spacing), D (25 cm spacing as a control). Kappaphycus alvarezii seeds used are the result of tissue culture that has been adapted on the beach. Measurements of chlorophyll-a and phycoerythrin were carried out using spectrophotometry and then the data were analyzed statistically. The results of this study found that the spacing of 25 cm (control) resulted in the highest chlorophyll-a content of 5.4986 mg/l with a phycoerythrin content of 0.0049 mg/l. The highest content of phicoeritrin is a spacing of 10 cm which is 0.0057 mg/l with a chlorophyll-a content of 4.7662 mg/l. A spacing of 25 cm can increase the chlorophyll-a content better because the spacing gives space for all parts of the Kappaphycus alvarezii thallus to be able to receive sufficient sunlight and is suitable for their needs. A spacing of 10 cm gives the highest content of phycoerythrin, which is 0.0057 mg / l because of the too-close this distance causes more shading to form and thus reduces the intensity of light entering the seaweed cell wall. On the part of the thallus that receives little or no sunlight, it is thought that the formation of phycoerythrin is more likely to occur as a form of adaptation of the seaweed thallus in conditions that do not get optimal sunlight. This study concludes that the spacing affects the chlorophyll-a and phicoeritrin content. The ideal spacing is 25 cm to produce the optimum chlorophyll-a content to support growth. Keywords: Photosynthesis, sunlight, thallus, growth, nutrients