Electronic Theses and Dissertation

Penelitian ini bertujuan mengevaluasi toksisitas ekstrak bakteri endofit bacillus sp. beds3 yang diisolasi dari daun singkong (manihot esculenta crantz), yang diketahui menghasilkan metabolit sekunder seperti flavonoid, fenolik, dan karotenoid dengan potensi sebagai agen antikanker. ekstraksi dilakukan menggunakan pelarut metanol (polar), etil asetat (semipolar), dan n-heksana (nonpolar). uji toksisitas dilakukan dengan metode brine shrimp lethality test (bslt) terhadap larva artemia salina, dan hasilnya dianalisis menggunakan regresi probit untuk menentukan nilai lc50. nilai lc50 masing-masing ekstrak yaitu 626,3 ppm (metanol), 777,6 ppm (etil asetat), dan 746,6 ppm (n-heksana), menunjukkan bahwa ekstrak metanol memiliki toksisitas paling tinggi. berdasarkan kategorisasi, ketiga ekstrak tergolong bersifat toksik. hasil ini menunjukkan bahwa polaritas pelarut berpengaruh terhadap efektivitas ekstraksi senyawa bioaktif dan mendukung potensi metabolit dari daun singkong sebagai kandidat agen terapeutik, termasuk antikanker. kata kunci:toksisitas, bakteri endofit, manihot esculenta, bslt, artemia salina

This study aimed to evaluate the toxicity of the endophytic bacterial extract Bacillus sp. BEDS3 isolated from cassava leaves (Manihot esculenta Crantz), which is known to produce secondary metabolites such as flavonoids, phenolics, and carotenoids with potential as anticancer agents. Extraction was carried out using methanol (polar), ethyl acetate (semipolar), and n-hexane (nonpolar) solvents. Toxicity testing was conducted using the Brine Shrimp Lethality Test (BSLT) on Artemia salina larvae, and the results were analyzed using probit regression to determine LC₅₀ values. The LC₅₀ values for each extract were 626.3 ppm (methanol), 777.6 ppm (ethyl acetate), and 746.6 ppm (n-hexane), indicating that the methanol extract had the highest toxicity. Based on the toxicity categorization, all three extracts were classified as toxic. These findings indicate that solvent polarity affects the effectiveness of bioactive compound extraction and support the potential of cassava leaf-derived metabolites as candidates for therapeutic agents, including anticancer. Keywords: Toxicity, endophytic bacteria, Manihot esculenta, BSLT, Artemia salina