Judul: Antibacterial Activity Test of Maggot (Hermetia illucens) Extract Against Respiratory Pathogenic Bacteria
Abstrak: Bakteri yang dapat menyebabkan pneumonia adalah bakteri Streptococcus pneumoniae, Haemophilus influenzae, dan Staphylococcus aureus. Maggot (Hermetia illucens) mengandung asam lemak melimpah yang berpotensi sebagai antimikroba dan belum pernah diteliti aktivitas antibakterinya terhadap bakteri patogen pernapasan. Penelitian ini bertujuan melakukan prediksi aktivitas biologis senyawa menggunakan PASS online dan analisis in vitro ekstrak maggot terhadap S. pneumoniae, H. influenzae, dan S. aureus. Ekstrak maggot diperoleh dari proses maserasi dengan pelarut metanol dan etil asetat. Fase atas dan fase bawah terbentuk setelah ekstrak etil asetat disentrifugasi. Hasil uji menunjukkan bahwa ekstrak etil asetat maggot memiliki aktivitas antibakteri terhadap ketiga bakteri uji. Mekanisme antibakteri berdasarkan analisis PASS adalah sebagai inhibitor peptidoglikan glikosiltransferase. Secara statistika, aktivitas antibakteri ekstrak etil asetat fase bawah terhadap S. pneumoniae adalah tidak berbeda nyata dengan antibiotik kloramfenikol, dan aktivitasnya terhadap H. influenzae lebih tinggi dibandingkan antibiotik kloramfenikol. Konsentrasi hambat minimum dan konsentrasi bunuh minimum oleh ekstrak etil asetat fase bawah terhadap ketiga bakteri uji sebesar 0,625% (v/v), serta fase atas sebesar 1,25-2,5% (v/v). Keseluruhan hasil pengujian menunjukkan potensi ekstrak maggot untuk dikembangkan sebagai kandidat antibakteri patogen pernapasan., The bacterias that cause pneumonia are Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus. Maggot extract (Hermetia illucens) contain fatty acids and has antimicrobial potency. Studies regarding its antibacterial activity against respiratory pathogenic bacterias have not been reported. This research aimed to predict biological activity of maggot extract through PASS online and in vitro study against S. pneumoniae, H. influenzae¸ and S. aureus. Maggot extract was obtained from maceration using methanol and ethyl acetate. Upper and lower phases were formed after the ethyl acetate extract was centrifuged. The result showed ethyl acetate extract has antibacterial activity against three tested bacterias. PASS analysis predicted its antibacterial mechanism as peptidoglycan glycosyltransferase inhibitor. Antibacterial activity of lower phase extract against S. pneumoniae is not significantly different from chloramphenicol, and its activity against H. influenzae is higher than chloramphenicol. Minimum inhibitory concentration and minimum bactericidal concentration the lower phase extract against three tested bacterias was 0,625% (v/v), and the upper phase was 1,25-2,5% (v/v). Overall results indicate potential of maggot extract to be further developed as respiratory pathogenic antibacterial candidate.
Keyword: antibacterial, H. influenzae, maggot, S. pneumoniae, S. aureus

Judul: Viability of Probiotics Fermentation Maggot (Hermetia illucens) on Temperature and Storage Time
Abstrak: Maggot (Hermetia illucens) merupakan insekta yang berpotensi dijadikan sebagai probiotik karena memiliki kandungan antimicrobial peptide (AMP) yang mampu menghambat pertumbuhan bakteri patogen pada saluran pencernaan inang. Masa simpan merupakan hal yang harus diperhatikan supaya menjaga kualitas suatu produk. Penelitian ini bertujuan menganalisis viabilitas probiotik fermentasi maggot yang diberi pengaruh lingkungan khususnya suhu dan lama waktu penyimpanan. Penelitian ini menggunakan 48 sampel probiotik fermentasi maggot, terdiri dari 12 perlakuan dan 4 ulangan yang dianalisis menggunakan Rancangan Acak Lengkap (RAL) pola faktorial yang terdiri dari 2 faktor. Faktor I merupakan perlakuan lama waktu penyimpanan dengan taraf B1: bulan ke-1, B2: bulan ke-2, dan B3: bulan ke-3. Faktor II merupakan suhu penyimpanan dengan taraf yaitu S1: 4°C, S2: 28°C, S3: 38°C, dan S4: 48°C. Parameter yang diamati yaitu kualitas fisik, populasi mikroba, total asam tertitrasi (TAT), dan zona hambat. Hasil penelitian menunjukkan adanya penurunan pada viabilitas probiotik seiring dengan lamanya penyimpanan. Masa simpan bepengaruh pada nilai total asam dan populasi bakteri asam laktat tapi tidak pada populasi mikroba lainnya dan zona hambat., Maggot (Hermetia illucens) is an insect that has potential to be used as a probiotic because it contains antimicrobial peptide (AMP) which can inhibit the growth of pathogenic bacteria in the digestive tract of the host. Shelf life is something that must be considered to maintain the quality of a product. This study aimed to analyze the viability of maggot probiotics which are influenced by the environment, especially temperature and storage time. This study used 48 maggot probiotic samples, consisting of 12 treatments and 4 replications which were analyzed using a completely randomized design (CRD) factorial pattern consisting of 2 factors. First factor was long storage time treatment with levels B1: 1st month, B2: 2nd month, and B3: 3rd month. Second factor is storage temperature with levels S1: 4°C, S2: 28°C, S3: 38°C, and S4: 48°C. The parameters observed were physical quality, population of microbes, titratable acidity (TA), and antimicrobial activity of maggot probiotics. The results showed that there was a decrease in the viability of probiotics along with the length of storage. Shelf life has an effect on the total acid and lactic acid bacteria, but has no effect on the population of other microbes and antimicrobial activity.
Keyword: maggot, probiotics, storage time, temperature, viability

Judul: Bifurkasi Hopf pada Model Siklus Bisnis Kaldor Kalecki tanpa dan dengan Waktu Tunda
Abstrak: Business cycle model is one of dynamical system models in economic. One of the business cycles model is Kaldor-Kalecki model. Kaldor-Kalecki business cycle model that is written in delayed defferential equations, is a business cycle model that involves gross product and capital stock of a company. In this paper Kaldor-Kalecki business cycle model is analyzed using both nondelay and delay in time of capital stock. By Taylor expansion for the time delayed model, an analysis of stability around the fixed points has been done. Furthermore, by using Hopf bifurcation theorem, it can be shown that there exists periodic orbits and limit cycle. In the nondelayed model, changing the parameter of goods market could lead to the occurrence of Hopf bifurcation and the existence of limit cycle. Similarly, for the delayed model, it has been shown that changing the time delay parameter may result in the occurrence of Hopf bifurcation and limit cycle.
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