east biomass is often used in the fermentation of bread dough. Dough fermentation can be maximized by adding a nitrogen source. This study used yeast isolates from salak pondoh (YIS-3, YIS-4, and ...YIS-7). The purpose of this study was to determine the effect of nitrogen addition on yeast growth and bread quality. This study used an experimental approach. The results of the growth study showed that all isolates treated with 0.05% urea produced higher biomass and cell counts than those treated with control. The highest biomass was produced by YIS-7, which was 3.81 g/300mL, while the highest number of cells was produced by YIS-3, which was 29.02x106 cells/mL. The percentage of proofing results showed that all yeast isolates treated with 0.05% urea needed a longer time to achieve the highest proofing. However, the volume of bread after baking showed better results than those treated with control. The largest volume of bread produced by YIS-3, was 972.14 cm3. The results of the organoleptic test showed that P<5%, which means that all treatments had a significant effect on the taste, aroma, color, and texture of the bread. Overall, the panelists gave good acceptance of the bread fermented by YIS-3 with 0.05% urea treatment. So it can be concluded that the addition of urea with a concentration of 0.05% in YIS-3 gave the best effect on the yeast growth and bread quality.
Beberapa jenis mikroba dapat menyebabkan patologis yang cukup serius bagi manusia ataupun makhluk hidup lainnya, salah satunya adalah Staphylococcus aureus dan Escherichia coli. Senyawa aktif dari ...daun sukun Artocarpus altilis memiliki aktivitas antimikroba, namun eksploitasi tanaman dapat mengakibatkan ketidakseimbangan ekosistem. Fungi endofit hidup di dalam sel jaringan tanaman sehat dan dapat menghasilkan jenis metabolit sekunder yang sama dengan tanaman inangnya. Tujuan penelitian ini adalah untuk mengisolasi dan menyeleksi fungi endofit dari daun A. altilis yang memiliki potensi sebagai agen antibakteri terhadap S. aureus dan E. coli. Metode yang digunakan yaitu isolasi fungi endofit dari daun A. altilis dan mengidentifikasinya secara makroskopis dan mikroskopis. Uji aktivitas antibakteri terhadap S. aureus dan E. coli dilakukan ekstraksi metabolit sekunder bakteri endofit dan uji fitokimia menggunakan metode difusi, pengenceran cair, dan padat. Berdasarkan hasil analisis didapatkan empat isolat fungi endofit daun A. altilis yang diberi kode IS01, IS02, IS03 dan IS04. Fungi endofit IS01 memiliki aktivitas antibakteri sangat kuat, IS03 kuat, IS02 sedang, dan IS04 lemah terhadap patogen E. coli dan kuat terhadap patogen S. aureus. Fungi endofit daun A. altilis dapat berperan sebagai antibakteri terhadap S. aureus dan E. coli.
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