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Masih rendahnya kemampuan pemecahan masalah matematika siswa SD dan masih belum optimalnya penggunaan media pembelajaran matematika di SD. Maka salah satu upayanya adalah dengan penggunaan media smart book. Tulisan ini bertujuan untuk mengetahui pengaruh media Smart Book terhadap kemampuan pemecahan masalah matematika SD dengan pokok bahasan bangun datar yang berfokus pada kemampuan kognitif siswa. Metode penelitian yang digunakan adalah metode eksperimen (pre-eksperimen) dari pendekatan kuantitatif dengan desain one group pretest-posttest design. Teknik pengambilan sampel dalam penelitian ini adalah Non Probality Sampling yaitu sampling jenuh dengan sampel sebanyak 21 siswa. Penelitian dilaksanakan di SDN Sindanghurip kecamatan Salawu. Instrumen yang digunakan adalah tes tulis berbentuk essay. Hasil penelitian menunjukan nilai rata-rata pretest =50,79 dan nilai rata-rata posttest =78,50. Hasil perhitungan uji t diperoleh = 11,51 dan = 2,08596, karena nilai = 11,51 diluar daerah penerimaan H₀ maka H₀ ditolak dan H₁ diterima. Sehingga dapat disimpulkan bahwa penggunaan media smart book dapat mempengaruhi kemampuan pemecahan masalah matematika siswa SD pada materi bangun datar yang berfokus pada kemampuan kognitif siswa tepatnya terhadap siswa kelas V SDN Sindanghurip

Background: Increased lipase activity can increase the amount of monoglycerides and fatty acids absorbed by the body, this is what affects obesity. If pancreatic lipase activity is inhibited, the production of fatty acids will decrease, consequently the level of fat in the blood will also decrease. Objective: To study anti obesity potential of a single herb or a mixture of green tea and other herbs (Syzygium polyanthum. Lv, Artocarpus communis.Lv, Cinnamomum verum..Lv, Manilkara zapota.Lv, Tectona grandis.Lv) by the in vitro inhibition assay of the lipase enzyme activity Method : A single (8 herbs) or a mixture of three herbs powder (12 formulas) was put into a tea bag with a total weight of 1.5 g to be brewed in 100 mL bottled mineral water at 70⁰-90⁰C for 10 minutes. In vitro lipase enzyme inhibition assay were conducted to measure the ability of these samples as lipase inhibitor. Orlistat used as positive lipase inhibitor. Results : There wa s a difference results of lipase inhibition activity between the sample of a single and a mixture of herbs. I nterestingly, the results shows that formula 3 (mixture of green tea, Manilkara zapota and cinnamon) . has 53.942 % inhibition , formula 9 ( a mixture of green tea, Syzygium polyanthum and cinnamon) has 67.322 % inhibition and formula 12 ( a mixture of green tea, Tectona grandis and cinnamon) has 56.612 % inhibition which close to lipase inhibitory activity by standard Orlistat. Conclusion: The mixture of green tea and two other herbs has a lipase inhibitory activity similar to Orlistat , when compared to the single herb. The highest lipase inhibitory activity is found in formula 9 .

Physics learning barriers have been studied quite a lot, one of which is epistemological learning barriers. This study aims to determine the epistemological learning barriers and what the percentage of epistemological learning barriers on Newton’s law material about motion in one of the engineering class at one of the vocational high school in Indonesia. Therefore, the researchers reported the results of research related to epistemological learning barriers. This research was qualitative descriptive research. The subjects of this research were 65 students with an age range of 14-15 years. The data was collected using tests and interviews, then analyzed using data reduction, data presentation, and conclusions. The data validity was determined using technical triangulation. The results of this research indicated that high epistemological barriers were found in two indicators, namely the incorrect calculation and the difficulty to determine the right calculation units on the Newton’s First, Second, and Third Laws with the percentages of 88.75%, 6.87%, and 98.45% respectively. The average percentage epistemological learning barriers on the Newton’s First Law was 61.7% within the moderate category and the average percentages of epistemological learning barriers on Newton’s Second and Third Laws were 70.61% and 76.50% within the high categories. Based on these results, it can be concluded that students had difficulty calculating and determining Newton’s Laws’ unit of calculation. It indicated that the students experience epistemological learning barriers with a high category.

Pada pembuatan yogurt terjadi konversi gula susu (laktosa) menjadi asam laktat melalui proses fermentasi oleh bakteri asam laktat (BAL). Konsentrasi stater dan waktu fermentasi yang digunakan akan mempengaruhi kecepatan perombakan laktosa menjadi asam laktat. Penelitian ini bertujuan untuk mengetahui pengaruh penambahan stater dengan variasi sebesar : 1, 5, 10, 15 dan 20% dan waktu fermentasi pada 24 jam dan 48 jam terhadap asam laktat. Parameter yang diuji diantaranya adalah pH, kadar laktosa, kadar protein, kadar asam lakat, dan aktivitas antioksidan. Parameter yang diuji dari hasil proses fermentasi adalah pH, laktosa, asam laktat, protein terlarut. Pengujian laktosa dan asam laktat dilakukan dengan menggunakan HPLC, pengujian konsentrasi protein terlarut dengan menggunakan metode Lowry. Asam laktosa dan asam laktat tertinggi diperoleh dari fermentasi dengan variasi konsentrasi BAL starter 15% dalam waktu fermentasi selama 24 jam. Hasil analisis % inhibisi pada yogurt konsentrasi stater 10% dan waktu fermentasi 48 jam tanpa penambahan dark coklat dan penambahan dark coklat menunjukkan % inhibisi antioksidan paling tinggi dibandingkan dengan yang lainnya sebesar 20,84 % dan 95,58%. Hasil penelitian Variasi starter konsentrasi BAL dan lamanya proses fermentasi tidak mempengaruhi pH dan kadar protein terlarut.

The aim of this study is to make a formula of green tea that is enriched by other herbs. Green tea drinks are made using the basic ingredients of gambung (THG) green tea enriched with sapodilla leaves ( Manilkara zapota (Aw) bay leaves ( Syzygium polyanthum (Am), Artocarpus communis (Un) breadfruit leaves, and cinnamon leaves ( Cinnamomum verum (K)). The composition of gambung herbal green tea is made by reference to the antidiabetic activity of each herb. All the samples were tested for inhibition of α-glucosidase enzymes and toxicity using the lethality test method for brine shrimp. All samples showed good inhibition of the α-glucosidase enzyme barriers of gamboeng green tea (THG) 82.05%, sapodilla leaves (Aw) 97.81%, breadfruit leaves (Un) 73.34%, bay leaves (Am) 93.80%, cinnamon leaves (K) 91.24 %. The inhibition value of α-glucoside enzymes in the formulation of gamboeng herbal green tea drinks: 96.203% (GKUn) is higher when compared to the GKAm formula (94.78%) and GKAw (62.487%).

This study aims to determine the effect of liquid media composition on the inhibitory activity of α-glucosidase from endophytic fungus Aspergillus elegans SweF9 isolated from seaweed (Macroalgae Euchema sp). Fermentation was carried out in three types of liquid media, namely: potato dextrose broth (PDB), potato malt peptone (PMP), and Czapek-dox broth (CDB), which was incubated for 10 days at room temperature, with static conditions. Ethyl acetate solvents were used to extract active metabolites from fungal biomass and filtrate from each media. Antidiabetic activity was measured based on inhibition of enzyme α-glucosidase. The results showed that filtrate extract of A. elegans SweF9 which was cultured on the media PDB showed highest inhibitor activity to the α-glucosidase enzyme with an IC50 value of 1.74 µg / mL compared to other extracts. Based on these results, the PDB media is an appropriate medium for culturing A. elegans SweF9 to produces secondary metabolites that can be used as a new source of antidiabetic agents.

Use of I±-glucosidase inhibitorsis one of the therapeutic approaches for decreasing postprandial hyperglycemia. Sulochrin (1) from Aspergillus terreus as well as two synthetic sulochrin derivatives were assessed for antidiabetic activity against yeast and rat intestine I±-glucosidase. Sulochrin showed potential inhibition against yeast I±-glucosidase, through a non-competitive mode with an IC50 value of 133.79 µM, and rat intestine I±-glucosidase by uncompetitive mode with an IC50 value of 144.59 µM.. Two synthetic derivatives of sulochrin were also prepared by bromination which resulted in dibromo-sulochrin (2) and tribromo-sulochrin (3). Preliminary SAR studies of sulochrin derivatives revealed that the yeast I±-glucosidase inhibitory activity of compound 2 and 3 increased than 1 due to substitution of hydrogen atom with bromine with IC50 values of 122.65 and 49.08 µM, respectively. However, the inhibitory activity against rat intestine I±-glucosidase of 2 and 3 was decreased compared to 1. To the best our knowledge, this is the first report of structure-activity relationship of sulochrin and its derivatives as I±-glucosidase inhibitors. These results suggested that sulochrin can potentially be used as a lead compound to develop new I±-glucosidase inhibitor from microorganisms. Keywords: Aspergillus terreus, I±-glucosidase inhibitory activity, sulochrin, bromination

Folic acid (Vitamin B9) involved in numerous metabolisms. Folate deficiency is responsible for some negative health problems. The fermentation of foodstuffs to produce rich content of folic acid beverages using lactic acid bacteria (LAB) is an effort to overcome the health issues. This study aimed to determine the effect of banana juice fermentation using LAB on the folic acid content of the banana juice. Banana juice was fermented for 48 hours at 37 o C with monoculture of Lactobacillus plantarum and mixed LAB cultures of Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus plantarum, Bifidobacterium bifidum and Bifidobacterium breve. The changes of folic acid characteristics were observed every 8 hours during 0 – 48 hours of fermentation, as well as the change in pH, total acid, soluble protein, and reducing sugar. The identification of folic acid monomers was conducted at the most optimal condition of the fermentation by using LC-MS. The result showed fermentation affect the folic acid content, pH, total acid, reducing sugar and soluble protein of banana juice. During fermentation, pH of the sample decreased with the increasing of total acid. Reducing sugar and soluble protein content tended to fluctuate. Optimal condition for folic acid enhancement was obtained by 32 hours of fermentation with mixed LAB, in which it yielded folic acid 34 . 07 μg/mL, pH . ,00, total acid 0 . 51%, reducing sugar 119 . 17 mg/L, dissolved protein 0 . 43 mg/mL. Folic acid identification on the optimal condition revealed that it was dominated by compound with a molecular weight of 441.49 Dalton. Keywords: banana, fermentation, folic acid, lactic acid bacteria ABSTRAK Asam folat (Vitamin B9) terlibat dalam berbagai metabolisme. Kekurangan folat bertanggung jawab atas beberapa masalah kesehatan. Fermentasi bahan pangan untuk menghasilkan minuman kaya asam folat menggunakan bakteri asam laktat (BAL) merupakan upaya untuk mengatasi masalah kesehatan akibat defisiensi folat. Penelitian ini bertujuan untuk mengetahui pengaruh fermentasi jus pisang menggunakan BAL terhadap kandungan asam folat jus pisang. Jus pisang difermentasi selama 48 jam pada suhu 37 o C dengan kultur tunggal Lactobacillus plantarum dan kultur campuran BAL yaitu Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus plantarum, Bifidobacterium bifidum dan Bifidobacterium breve. Perubahan karakteristik asam folat diamati setiap 8 jam selama 0-48 jam fermentasi. Selain itu, diamati pula perubahan pH, total asam, protein terlarut dan gula pereduksi. Identifikasi monomer asam folat dilakukan pada kondisi fermentasi paling optimum dengan menggunakan LC-MS. Hasil penelitian menunjukkan bahwa fermentasi dapat mempengaruhi kandungan asam folat, pH, total asam, gula pereduksi dan protein terlarut dari jus pisang. Selama fermentasi, pH sampel menurun diikuti dengan peningkatan total asam. Nilai gula pereduksi dan protein terlarut cenderung berfluktuasi. Kondisi optimum peningkatan kandungan asam folat diperoleh pada fermentasi menggunakan mix kultur LAB selama 32 jam dengan kandungan asam folat 34,07 mg/mL, pH 4,00, total asam 0,51%, gula pereduksi 119,17 mg/L dan protein terlarut 0,43 mg/mL. Identifikasi monomer asam folat pada kondisi optimum fermentasi didominasi senyawa dengan berat molekul 442,49 Dalton (Da). Kata kunci: asam folat, bakteri asam laktat, fermentasi, pisang

Butyrolactone I (BL-I) has been reported as inhibitor of α-glucosidase and antioxidant compound isolated from culture broth of Aspergillus terreus. The purpose of this study was to determine the effect of various liquid media compositions on production of BL-I from A. terreus LS07. Fermentation was conducted in four liquid medium: potato dextrose broth (PDB), potato malt peptone (PMP), malt extract (ME), and Czapek-Dox broth (CDB), which were incubated for seven days at room temperature, with agitation of 70 rpm. Ethyl acetate (EtOAc) was used to extract the active metabolite from each broth. Glucosidase inhibitory activity was measured by the inhibition of yeast α-glucosidase, while antioxidants measured by testing the total phenol and DPPH free radical scavenger activity. The results showed that the EtOAc extract on CDB had strong inhibition activity against the enzyme α-glucosidase and strong antioxidant with IC50 values 6.45 and 24.05 μg/mL, respectively. The CDB extract also showed the highest content of total phenols (349.66 mg Gallic Acid Equivalent (GAE)/g extract) and BL-I (58.5% w/w). Based on these results, among the four kinds of medium used, Czapek-Dox broth is an ideal culture medium of A. terreus LS07 that could be applied for increase production of BL-I as natural antidiabetic source from terestrial fungi

The antibiotic resistance of bacterial pathogens has become a serious health concern and encouragement to search for novel and efficient antimicrobial metabolites. On the other hand, endophytic fungi have great potential as a natural source for antimicrobial agents. The objective of this study was to isolation antibacterial compound from endophytic fungi of A.elegans SweF9. The fungus was stationarily cultured at 30°C for 12 days in potato malt peptone (PMP) medium, then extracted with ethyl acetate. The antibacterial activities of the extract were evaluated by agar well diffusion method against Gram-poitive ( Bacillus subtilis and Staphylococcus aureus) and Gram-negative ( Escherichia coli ) bacterial strains. The broth extract was able to inhibit the growth of E. coli , S. aureus and B. subtilis with antibacterial activity index compared to streptomycin sulfate were 84.6%, 91.6%, and 90% respectively. The active compound (1) was purified to yield amorphous white and identified using FTIR, NMR, and EI-MS analyses, revealed identified as (+) - epi-Epoformin. The compound showed an antibacterial activity index of E. coli , S. aureus and B. subtilis bacterial were 38%, 45%, and 47%, respectively. Based on these results endophytic fungi A. elegans SweF9 can be used as a new source of potential antibacterial compounds

Lovastatin is an anti-cholesterol agent that was produced by Aspergillus terreus using solid state fermentation (SSF). During this fermentation process, sulochrin is also produced as an unwanted co-metabolite. However, our previous result showed that sulochrin had potential as antidiabetes because it is an inhibitor agent of α-glucosidase. In this paper, we reported our observation on lovastatin and sulochrin production pattern in relation with inhibitor α-glucosidase activity during eleven days fermentation of A. terreus koji (SSF) ethyl acetate extract. Koji obtained from solid state fermentation with rice as the substrate and incubated at room temperature, sample is taken daily for eleven day (D-1 to D-11). Lovastatin and sulochrin production was measured by Liquid Chromatography- Mass Spectrometer based on their molecular weight m/z 404.5 and 332.3 respectively. The inibitory activity is measured by inhibition model of koji extract against α-glucosidase (EC 3.2.1.20) from Saccharomyces cereviceae. The results show that lovastatin production was started on the day 2 (0.04 mg/g) and achieving the optimal production on day 7 (11.46 mg/g), while sulochrin production was started on day 4 (0.60 mg/g) and keep produced until the end of fermentation period at Day 11 (3.11 mg/g). Koji extract was started to show inhibitory to α-glucosidase activity on Day 5 (IC50= 23.34 μg/mL) and keep showed activity until Day 11 (IC50=3.33 μg/mL). These results suggest that inhibitory activity of koji extract to α- glucosidase activity have relation with sulochrin biosynthesis production.

A crude peroxidase biocatalyst extracted from sawi hijau ( Brassica juncea ) was used to produce dimerization phenolic synthesized from eugenol. The result from MS and NMR analysis showed that the reaction between eugenol substrate and H 2 O 2 with crude extract enzyme produced a new chemical compound. The chemical structure of new compound showed coupled result in ortho-ortho position with C-C coupled derivative, dehydrodieugenol. It was obtained as brownish white crystal needles with yield 10%. This compound displayed higher cytotoxicity effect on T47D breast cancer cell compared to the eugenol monomer.

Ethanol is a potential industrial chemical as a very promising biofuel to replace fossil fuels. Its capability to increase octane number and improve the emissions quality of gasoline drives the researches in efficient ethanol production. A rapid fermentation leading to high ethanol concentration; therefore a yeast strain with a good specific ethanol production rate becomes the main consideration. Due to several advantages presenting by the using of cell immobilization, such as increased productivity, reduced risk of contamination, biocatalyst recycling, rapid product separation and others, the interest of cell immobilization for ethanol production has increased in the last decades. The great importance to find cheap, abundant, and non-destructive immobilization supports, rice flour and white glutinous rice flour were tested as support for yeast immobilization in the present work. Three commercial yeast strains were used in the experiments, labelled A, B, and C. The fermentation runs were carried out with glucose as substrate in 250 mL Erlenmeyer flask containing 100 mL of medium and 5% of immobilized enzyme loading and statically incubated at 32oC for 72 hours. Fermentations were carried out in duplicate and fermentations under the same conditions described above were also performed without support addition for comparison. The results showed that white glutinous rice flour was great potential for use as immobilization support during the ethanol production by the C yeast strain culture.