?url_ver=Z39.88-2004&rft_id=2117061007&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Adc&rft.title=UJI+AKTIVITAS+ANTIOKSIDAN+EKSTRAK+METANOL+DAN+ETIL+ASETAT+Gracilaria+sp.+MENGGUNAKAN+METODE+DPPH+(2%2C2-difenil-1-pikrilhidrazil)&rft.creator=PUZA+%2C+WIDIYA+NINGSIH&rft.subject=570+Biologi&rft.description=Radikal+bebas+adalah+molekul+yang+tidak+stabil+dan+memiliki+elektron+yang+tidak+berpasangan.+Antioksidan+adalah+senyawa+yang+memiliki+kemampuan+untuk+menghambat+reaksi+oksidasi+dengan+mengikat+radikal+bebas+dan+molekul+yang+sangat+reaktif.+Antioksidan+dari+luar+dapat+diperoleh+dalam+bentuk+sintetik+dan+alami.+Adanya+dampak+negatif+pada+antioksidan+sintetik+membuat+penelitian+antioksidan+alami+semakin+berkembang.+Salah+satu+tanaman+yang+dapat+diteliti+sebagai+antioksidan+alami+adalah+Gracilaria+sp.+yang+merupakan%2C+salah+satu+jenis+alga+yang+memiliki+potensi+sebagai+antibakteri%2C+antijamur+dan+antioksidan.+Penelitian+ini+menggunakan+pelarut+ekstraksi+metanol+dan+etil+asetat+karena+polaritas+yang+berbeda%2C+penggunaan+pelarut+dengan+polaritas+yang+berbeda+akan+mempengaruhi+hasil+ekstraksi.+Tujuan+penelitian+ini+adalah+untuk+mengetahui+senyawa+metabolit+sekunder+yang+terkandung+pada+Gracilaria+sp.+dan+mengetahui+aktivitas+antioksidan+dari+ekstrak+metanol+dan+etil+asetat+Gracilaria+sp.+menggunakan+metode+DPPH+(2%2C2-difenil-1-pikrilhidrazil).+Kemudian%2C+diukur+menggunakan+Spektrofotometer+UV-Vis+pada+panjang+gelombang+maksimum+517+nm.+Data+dianalisis+dengan+menggunakan+persamaan+regresi+linear+untuk+menemukan+IC50.+Hasil+penelitian+menunjukkan+Gracilaria+sp.+mengandung+senyawa+alkaloid%2C+flavonoid%2C+tanin%2C+saponin%2C+fenol%2C+dan+steroid.+Aktivitas+antioksidan+Gracilaria+sp.+ekstrak+metanol+dengan+nilai+IC50+158%2C91%2C+tergolong+lemah.+Sementara+itu%2C+ekstrak+etil+asetat+memiliki+nilai+IC50+sebesar+252%2C07+yang+tergolong+kedalam+kategori+sangat+lemah.%0D%0A%0D%0AKata+Kunci%3A+Antioksidan%2C+Radikal+bebas%2C+DPPH+(2%2C2-difenil-1-pikrilhidrazil)+Gracilaria+sp.%0D%0A%0D%0A%0D%0A%0D%0A%0D%0A%0D%0A%0D%0A%0D%0Aabstract%0D%0A%0D%0AFree+radicals+are+unstable+molecules+and+have+unpaired+electrons.+Antioxidants+are+compounds+that+have+the+ability+to+inhibit+oxidation+reactions+by+binding+free+radicals+and+highly+reactive+molecules.+External+antioxidants+can+be+obtained+in+synthetic+and+natural+form.+The+negative+impact+of+synthetic+antioxidants+has+made+research+on+natural+antioxidants+increasingly+developed.+One+plant+that+can+be+studied+as+a+natural+antioxidant+is+Gracilaria+sp.+which+is+a+type+of+algae+that+has+potential+as+an+antibacterial%2C+antifungal+and+antioxidant.+This+research+uses+methanol+and+ethyl+acetate+extraction+solvents+because+of+different+polarities%2C+the+use+of+solvents+with+different+polarities+will+affect+the+extraction+results.+The+aim+of+this+research+is+to+determine+the+secondary+metabolite+compounds+contained+in+Gracilaria+sp.+and+determine+the+antioxidant+activity+of+methanol+and+ethyl+acetate+extracts+of+Gracilaria+sp.+using+the+DPPH+(2%2C2-diphenyl-1-picrylhydrazyl)+method.+Then%2C+it+was+measured+using+a+Spectrophotometer+UV-Vis+at+a+maximum+wavelength+of+517+nm.+Data+were+analyzed+using+a+linear+regression+equation+to+find+IC50.+The+results+showed+that+Gracilaria+sp.+contains+alkaloids%2C+flavonoid%2C+tannin%2C+saponin%2C+phenol+and+steroid.+Antioxidant+activity+of+Gracilaria+sp.+methanol+extract+with+an+IC50+value+of+158.91%2C+classified+as+weak.+Meanwhile%2C+ethyl+acetate+extract+has+an+IC50+value+of+252.07+which+is+classified+as+very+weak.%0D%0A%0D%0AKeywords%3A+Antioxidants%2C+Free+radicals%2C+DPPH+(2%2C2-diphenyl-1-picrylhydrazyl)+Gracilaria+sp.&rft.publisher=FAKULTAS+MATEMATIKA+DAN+ILMU+PENGETAHUAN+ALAM+&rft.date=2025-03-12&rft.type=Skripsi&rft.type=NonPeerReviewed&rft.format=text&rft.identifier=http%3A%2F%2Fdigilib.unila.ac.id%2F86259%2F1%2FABSTRAK.pdf&rft.format=text&rft.identifier=http%3A%2F%2Fdigilib.unila.ac.id%2F86259%2F2%2FSKRIPSI%2520FULL.pdf&rft.format=text&rft.identifier=http%3A%2F%2Fdigilib.unila.ac.id%2F86259%2F3%2FSKRIPSI%2520TANPA%2520BAB%2520PEMBAHASAN.pdf&rft.identifier=++PUZA+%2C+WIDIYA+NINGSIH++(2025)+UJI+AKTIVITAS+ANTIOKSIDAN+EKSTRAK+METANOL+DAN+ETIL+ASETAT+Gracilaria+sp.+MENGGUNAKAN+METODE+DPPH+(2%2C2-difenil-1-pikrilhidrazil).++FAKULTAS+MATEMATIKA+DAN+ILMU+PENGETAHUAN+ALAM+%2C+UNIVERSITAS+LAMPUNG.+++++&rft.relation=http%3A%2F%2Fdigilib.unila.ac.id%2F86259%2F