Preparasi dan Karakterisasi Senyawa Tanin dari Daun Stevia (Stevia Rebaudiana) Menggunakan Instrumen HPLC sebagai Gula Pereduksi dalam Pembuatan Sukrosa

Daun stevia merupakan salah satu jenis tanaman herbal yang menghasilkan sukrosa alami yang dapat dimanfaatkan dalam aplikasi pemanis dalam skala industri maupun rumah tangga. Metode penelitian yang digunakan dalam penelitian ini adalah ekstraksi senyawa tannin menggunakan karbon aktif. Karbon aktif dianalisis senayawa kimianya dan diidentifikasi gugus fungsi menggunakan FTIR. Senyawa tannin dari daun stevia dilakukan proses ektraksi dengan menggunakan perut etanol dan dianalisis senyawa kandungan tannin dengan menggunakan HPLC. Karbon aktif yang digunakan dalam proses ekstraksi sesuai dengan standar SNI dalam batas pemakaian penggunaanya sebagai adsorben dalam proses adsorpsi senyawa tannin. Gugus fungsiyang dihasilkan dari karbon aktif adalah vibrasi ulur O-H, C-O, C=O, C-H aromatik dan C-H finger print. Kadar senyawa kandungan tannin dari daun stevia yaitu 0,0122% dan 0,0123% dengan menggunakan pelarut etanol 30% dan 70%

Preparasi dan Karakterisasi Senyawa Tanin dari Daun Stevia (Stevia Rebaudiana) Menggunakan Instrumen HPLC sebagai Gula Pereduksi dalam Pembuatan Sukrosa

Daun stevia merupakan salah satu jenis tanaman herbal yang menghasilkan sukrosa alami yang dapat dimanfaatkan dalam aplikasi pemanis dalam skala industri maupun rumah tangga. Metode penelitian yang digunakan dalam penelitian ini adalah ekstraksi senyawa tannin menggunakan karbon aktif. Karbon aktif dianalisis senayawa kimianya dan diidentifikasi gugus fungsi menggunakan FTIR. Senyawa tannin dari daun stevia dilakukan proses ektraksi dengan menggunakan perut etanol dan dianalisis senyawa kandungan tannin dengan menggunakan HPLC. Karbon aktif yang digunakan dalam proses ekstraksi sesuai dengan standar SNI dalam batas pemakaian penggunaanya sebagai adsorben dalam proses adsorpsi senyawa tannin. Gugus fungsiyang dihasilkan dari karbon aktif adalah vibrasi ulur O-H, C-O, C=O, C-H aromatik dan C-H finger print. Kadar senyawa kandungan tannin dari daun stevia yaitu 0,0122% dan 0,0123% dengan menggunakan pelarut etanol 30% dan 70%

PENGARUH PROFITABILITAS TERHADAP RETURN SAHAM PADA PERUSAHAAN MANUFAKTUR DIBURSA EFEK INDONESIA (BEI)

Penehtian mi bertujuan untuk mengetahui bagaimana pengaruh Profitabilitas terhadap Return Saham pada perusahaan manufaktur Di Bursa Efek Indonesia (BEI). Variabel bebas (X) yang digunakan dalam penelitian ini adalah Profitabilitas dengan menggunakan indikator Return On Equity dan Earning Per Share, sedangkan variabel tenkat (Y) diwakili oleh return saham dengan menggunakan indikator selisih harga saham (Actual Return). Metode penelitian yang digunakan dalam penelitian ini adalah metode desknptif-venfikatif. Teknik sampling yang digunakan oleh penulis adalah purposive sampling. Sedangkan hipotesis yang diajukan dalam penelitian ini adalah. 'Profitabilitas mempunyai pengaruh positif terhadap Return Saham " Berdasarkan perhitungan yang telah dilakukan diperoleh hasil koefisien regresi masing-masing indikator variabel independen (Return On Equity dan Earning Per Share) menunjukkan angka yang bermlai positif masing-masmg sebesar 0,353 dan 4,714E-5. Berdasarkan uraian di atas dapat disimpulkan bahwa pada rtaftun ^009 profitabilitas berpengaruh positif terhadap return saham perusahaan manufaktur yang terdaftar di Bursa Efek Indonesia. Kata kunci: Profitabilitas, Return On Equity, Earning per share Actual Return dan return saha

Vegetation structure, biomass, and carbon of Mangrove Forests in Ambon Bay, Maluku, Indonesia

Mangrove forests serve a substantial part in coastal areas as high-carbon-storage woody vegetation ecosystems that grow on muddy and anaerobic soils. This study determined the species composition and estimated the biomass production and storage of carbon in Ambon Bay mangrove forests. Vegetation surveys for species composition were conducted using the square plot technique by making standard observation plots for density, frequency, dominance, and important value index data analysis. We used Allometric equations and the Loss-on-ignition method to calculate the biomass and soil carbon. Vegetation surveys revealed eight species of tree-habitus mangroves, and Sonneratia alba was a mono-dominant species with an important value index of more than 100%. The study revealed the highest average potential of biomass and carbon in Passo Village with AGB 280.47±168.94 Mg ha-1, BGB 83.06±55.1 Mg ha-1, and sediment carbon 320.03±106.97 Mg C ha-1. The carbon stock of the mangrove forest in Ambon Bay was estimated at 400.67±166.25 Mg C ha-1. We conclude that mangrove forest carbon stores in Ambon Bay had relatively high values. Passo Village has the largest carbon store compared to other locations in the Ambon Bay mangrove forest.Hutan mangrove berperan penting di wilayah pesisir sebagai ekosistem vegetasi berkayu penyimpan karbon tinggi yang tumbuh pada tanah berlumpur dan anaerobik. Penelitian ini dilaksanakan pada bulan November 2021 sampai dengan Januari 2022 bertujuan untuk mengetahui komposisi jenis dan menduga biomassa dan simpanan karbon hutan mangrove di Teluk Ambon, untuk dijadikan acuan dalam pengelolaan hutan mangrove. Survei vegetasi dilakukan dengan teknik petak persegi dengan membuat petak pengamatan standar untuk analisis data kerapatan, frekuensi, dominansi, dan indeks nilai penting. Persamaan alometrik digunakan untuk pendugaan biomassa pohon. Metode loss-on-ignition digunakan untuk memperkirakan karbon tanah. Hasil penelitian menemukan 8 spesies mangrove dengan habitus pohon. Sonneratia alba ditemukan sebagai spesies monodominan dengan indeks nilai penting lebih dari 100%. Penelitian menemukan rata-rata potensi biomassa dan karbon tertinggi di Desa Passo dengan AGB 280,47±168,94 Mg ha-1, BGB 83,06±55,1 Mg ha-1, dan karbon sedimen 320,03±106,97 Mg C ha-1. Stok karbon hutan mangrove di Teluk Ambon diperkirakan sebesar 400,67±166,25 Mg C ha-1. Kami menyimpulkan simpanan karbon hutan mangrove di Teluk Ambon cukup tinggi, terutama di Desa Passo yang merupakan lahan simpanan karbon terbesar

Evaluation of Land Suitability for Brackishwatershrimp Farming using GIS in Mahakam Delta, Indonesia

This paper briefly described land evaluation of shrimp farming development in Mahakam Delta, discusses its ecological and socio-economic impacts and recommends measures to achieve long term sustainability using Geographic Information System (GIS). The objectives of this research were to know land evaluation based on suitability for brackish water aquaculture and optimal utilazation level. This reserarch was conducted at Mahakam Delta Sub Distric Kutai Kartanegara; East Kalimantan. Surveys have been done collected primary data, while secondary data was obtained from related institution and needed maps for GIS analysis, with overlying map and primary data in each station observation with considering and assessment scale value of determining land suitability for brackish water pond using  AHP method.The result of GIS analysis had been obtained the land suitability at Mahakam Delta, area of highly suitable for shrimp pond was 1,185 ha (3.02%), suitable was 32,137 ha (81.93%), and not suitable was 5,905 ha (15.05 %) of 39,226 ha total land area that was studied. It can be concluded the sites with generality were suitable based on potential for pond construction, water availability, and water quality but not suitable for soil quality and infrastructure facilities. Keywords: GIS, Land suitability, Shrimp pond, Analytic Hierarchy Process (AHP), Land use evaluatio

Adaptive Mangrove Ecosystem Rehabilitation Plan based on Coastal Typology and Ecological Dynamics Approach

Mangrove rehabilitation has implications for important ecological, social and economic values for coastal communities. The mangroves ecosystem Karawang Regency is still under pressure due to the management and utilization that does not pay attention to the sustainability aspect. The rehabilitation plan to mangrove management must be adapted to the nature and characteristics of the habitat. This study aims to formulate technical considerations for the direction of a rehabilitation plan based on an ecological approach and the dynamics of the mangrove ecosystem. The methods used in this study were geospatial approach that integrated with field quanitative and qualitative data. The results show that the total of mangrove potential area in Karawang Regency was 19,139.53 ha, consisting of 421.95 ha (2.2%) of vegetated area and 18,717.58 ha (97.8%) of unvegetated area. We integrate mangrove typology, mangrove stand density, physical parameters, and land use as the basis for determining the direction of rehabilitation planning. In the estuarine deltaic mangrove typology, we aim at protecting with natural regeneration. In infringe areas, we recommend constructing natural coastal structures before planting. On the backward for intensive planting. Furthermore, mangroves with low density, medium density, and high density are recommended for planting, species enrichment, and protecting respectively, and on the pond with implementing the mixed mangrove-aquaculture system to bridge between rehabilitation effort and economic needs of coastal communities

Vegetation structure, biomass, and carbon of Mangrove Forests in Ambon Bay, Maluku, Indonesia

Mangrove forests serve a substantial part in coastal areas as high-carbon-storage woody vegetation ecosystems that grow on muddy and anaerobic soils. This study determined the species composition and estimated the biomass production and storage of carbon in Ambon Bay mangrove forests. Vegetation surveys for species composition were conducted using the square plot technique by making standard observation plots for density, frequency, dominance, and important value index data analysis. We used Allometric equations and the Loss-on-ignition method to calculate the biomass and soil carbon. Vegetation surveys revealed eight species of tree-habitus mangroves, and Sonneratia alba was a mono-dominant species with an important value index of more than 100%. The study revealed the highest average potential of biomass and carbon in Passo Village with AGB 280.47±168.94 Mg ha-1, BGB 83.06±55.1 Mg ha-1, and sediment carbon 320.03±106.97 Mg C ha-1. The carbon stock of the mangrove forest in Ambon Bay was estimated at 400.67±166.25 Mg C ha-1. We conclude that mangrove forest carbon stores in Ambon Bay had relatively high values. Passo Village has the largest carbon store compared to other locations in the Ambon Bay mangrove forest

Application of Tank Model for Predicting Water Balance and Flow Discharge Components of Cisadane Upper Catchment

The concept of hydrological tank model was well described into four compartments (tanks). The first tank (tank A) comprised of one vertical (qA0) and two lateral (qA1 and qA2) water flow components and tank B comprised of one vertical (qB0) and one lateral (qB1) water flow components. Tank C comprised of one vertical (qC0) and one lateral (qC1) water flow components, whereas tank D comprised of one lateral water flow component (qD1).  These vertical water flows would also contribute to the depletion of water flow in the related tanks but would replenish tanks in the deeper layers. It was assumed that at all lateral water flow components would finally accumulate in one stream, summing-up of the lateral water flow, much or less, should be equal to the water discharge (Qo) at specified time concerns. Tank A received precipitation (R) and evapo-transpiration (ET) which was its gradient of (R-ET) over time would become the driving force for the changes of water stored in the soil profiles and those water flows leaving the soil layer.  Thus tank model could describe th vertical and horizontal water flow within the watershed. The research site was Cisadane Upper Catchment, located at Pasir Buncir Village of Caringin Sub-District within the Regency of Bogor in West Java Province.  The elevations ranged 512 –2,235 m above sea level, with a total drainage area of 1,811.5 ha and total length of main stream of 14,340.7 m.  The land cover was dominated by  forest  with a total of 1,044.6 ha (57.67%),  upland agriculture with a total of 477.96 ha (26.38%), mixed garden with a total of 92.85 ha(5.13%) and semitechnical irigated rice field with a total of 196.09 ha (10,8%).  The soil was classified as hydraquent (96.6%) and distropept (3.4%).  Based on the calibration of tank model application in the study area, the resulting coefficient of determination (R2) was 0.72 with model efficiency (NSE)of= 0.75, thus tank model could well illustrate the water flow distribution of Cisadane Upper Catchment. The total water yield was 2.789 mm year-1 from 3,624 mm year-1 of total annual precipitation.  The total water yield comprised of a total runoff of 47.39% and  49.23%  of sub surface flow and base flow