Chlorophyll is one of the most used coloring materials derived from green leaves and other parts of almost all green plants. It contains several components that are beneficial to health: vitamins, antioxidants, antibacterial, anti-inflammatory; hence, chlorophyll is a nutraceutical. Chlorophyll has been developed by extracting green plants, for instance, katuk leaves (Sauropus androgynous). A review of various chlorophyll extraction methods from natural ingredients was done to obtain the most suitable katuk leaves. Preliminary experiments had been carried out to develop the chlorophyll stability of katuk leaves on the influence of temperature, pH, and storage time. The chlorophyll content of katuk leaves decreased at high temperatures. Extraction using supercritical/subcritical CO2 can extract components selectively so that it is suitable for extraction applications for products that are not heat resistant. Meanwhile, carbon dioxide (CO2) as a supercritical/subcritical solvent has several advantages, including producing an inert gas that is non-toxic, non-flammable, and cheap. Under normal gas conditions, it is straightforward to separate CO2 and dissolved components without heating and producing extracts free of solvents. The most suitable chlorophyll extraction method of katuk leaves was supercritical/subcritical CO2 extraction because it could prevent chlorophyll degradation.
This study focused in the effect of water content on biofilm and bio-corrosion, and knowing its influence on biodiesel-diesel blends’ quality. Biodiesel is hygroscopic and less stable, makes this fuel needs more attention in storing. Fuel is usually stored in a storage tank of carbon steel which easily corroded by microorganisms, such as Bacillus megaterium. Corrosion occurs because microorganisms use fuel as nutrients and water content in hygroscopic biodiesel supports to grow and metabolize. Experiments were carried out by immersing carbon steel in medium 30% biodiesel (B30) for 21 days with water content variation of 0%, 5%, and 10% volume. The number of colonies in biofilms increased up to 1,3 times in a 10% water content. A uniform biofilm provides an inhibitory effect on corrosion per time, also layer of iron phosphate formed on water content variation, so the highest 0.642 ± 0.28 mm/year on 0% water content. Fe2O3, Fe3O4, and FeOOH are the corrosion product by Bacillus megaterium. The highest biodegradation efficiency achieved by variation water content both 5% and 10% were 68.5% and 67.23%, and then followed by no water content at 60.40%.
<p class="Default"><em>Agricultural waste</em> adalah limbah yang dihasilkan dari sektor pertanian, seperti limbah jerami, ampas tebu, dan pelepah sawit. Limbah pertanian tersebut mengandung lignoselulosa. Lignoselulosa adalah komponen yang terdiri atas selulosa, hemiselulosa, dan lignin. Adanya kandungan selulosa dapat dimanfaatkan menjadi berbagai produk, namun kandungan lignin dan hemiselulosa dapat menghambat proses hidrolisis lignoselulosa. Selulosa memiliki banyak kegunaan seperti bahan baku propelan atau bahan peledak, serta turunan dari alfa-selulosa dapat diproses menjadi produksi bioetanol, asam glutamat, <em>biosolvent</em> alkohol, dll. Metode hidrolisis lignoselulosa sangat mempengaruhi kadar <em>fermentable</em><em> sugar</em> yang dihasilkan. Upaya penelitian telah dilakukan untuk meningkatkan hidrolisis lignoselulosa. <em>Pretreatment</em> bahan untuk menghilangkan lignin dan hemiselulosa serta optimasi enzim xilanase dan selulase secara signifikan meningkatkan kemampuan hidrolisis lignoselulosa. Sakarifikasi dan hidrolisis simultan efektif meningkatkan hasil dan laju hidrolisis lignoselulosa. Sehingga perlu pendekatan lebih lanjut untuk mengetahui efektifitas berbagai metode yang digunakan dalam melakukan optimasi pemecahan rantai lignoselulosa. Fokus pada review paper ini adalah metode yang dapat digunakan dalam hidrolisis lignoselulosa <em>agricultural waste </em>sebagai optimasi produksi <em>fermentable</em><em> sugar</em>, diantaranya: metode <em>pretreatment</em><em>,</em> delignifikasi, hidrolisis dan sakarifikasi. Selanjutnya dilakukan pengolahan lanjut dari <em>fermentable</em><em> sugar.</em></p>
<div class="WordSection1"><p><strong>Abstract.</strong> Petroleum based fuel is the main energy source used in the world. However, there is a future problem with the declined petroleum reserves. Therefore changing to alternative energy resource is a must. This reserach was to investigate the effects of feed flowrate and recycle flow rate on bioethanol fermentation process using integrated aerobic-anaerobic baffled reactor, especially on bioethanol production and sugar consumption. Start up process was run with working volume of 25 L medium for 54 hours incubation. The recycle flow varried into 5 L/h and 10 L/h when the feed rate was 12.6 L/h. In other experiments, the feed flow rate was run at 5 and 12.6 L/h when the recycle flow rate was 10 L/h. The broth samples were taken out periodically for measurements of bioethanol concentration, yeast population and residual sugar of consumptions. The experiments results in the highest bioethanol concentration of 14% v/v at the effluent of reactor. It is higher from the process without recyle of process medium. Nevertherless, no difference effect of the recycle flow rate of 5 L/h and 10 L/h on the bioethanol production.</p><p> <strong>Keywords:</strong> Bioethanol, Baffled Reactor, Feed, Recycle</p></div>
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.