scholarly journals Efek Pretreatment Microwave-NaOH Pada Tepung Gedebog Pisang Kepok terhadap Yield Selulosa

2018 ◽  
Vol 38 (2) ◽  
pp. 133
Author(s):  
Dewi Maya Maharani ◽  
Khulafaur Rosyidin

Carbon sources in the form of sugar to be converted into bioethanol are rapidly developed, they are so called as the first generation, the second generation, and the third generation. The petiole of banana is the second generation of lignocellulose which is a waste and potential in Indonesia to be used as the raw material of bioethanol production. This study aimed to determine the effect of the microwave to the content of petiole`s flour of “gepok” varieties and to know the effect of pretreatment time as well as the ratio of petiole mass to the resulted flour with the solvent of NaOH for bioethanol production. The 20 g of petiole with the size of 60 mesh was dissolved into NaOH 0.5 M with the variation of solvent volume 150 mL, 200 mL and 250 mL then was pretreated with microwave as long as 20, 30, and 40 minutes. Annova resulted that time variable affected the cellulose content however the volume didn`t. Cellulose is a compound which is going to be converted into glucose. Hence, in this study, the lowest decrease of cellulose 350,20 mg/g was chosen from the microwave pretreatment with a yield of 93,10% at 20 g: 250 mL for 30 minutes.  ABSTRAKSumber karbon dalam gula untuk dikonversi menjadi bioetanol banyak mengalami perkembangan, mulai dari sumber bioetanol generasi satu, generasi dua dan generasi tiga. Gedebog pisang merupakan salah satu limbah berlignoselulosa generasi dua yang potensial di Indonesia dan memiliki kandungan selulosa tinggi yang dapat dimanfaatkan sebagai bahan baku produksi bioetanol. Penelitian ini bertujuan untuk mengetahui pengaruh gelombang microwave terhadap kandungan selulosa tepung (gedebog) pisang kepok dan mengetahui pengaruh lama pretreatment serta perbandingan massa bahan dengan volume pelarut NaOH terhadap kandungan selulosa tepung (gedebog) pisang kepok pada proses pretreatment yang dimanfaatkan untuk produksi bioetanol. Gedebog pisang ukuran 60 mesh sebanyak 20 g dilarutkan pada larutan NaOH 0,5 M dengan variasi volume pelarut 150 mL, 200 mL, dan 250 mL, selanjutnya diberi perlakuan (pretreatment) gelombang microwave dengan variasi waktu 20, 30 dan 40 menit. Pada hasil uji lanjut Annova menyatakan bahwa variabel waktu memberikan pengaruh nyata terhadap kandungan selulosa sedangkan interaksi antara variabel dan volume tidak memberikan pengaruh nyata terhadap kandungan selulosa. Selulosa merupakan senyawa yang akan dikonversi lebih lanjut menjadi glukosa. Sehingga pada penelitian ini memilih penurunan selulosa terendah yaitu menjadi 350,20 mg/g akibat pretreatment microwave-NaOH dengan rendemen 93,10% pada perlakuan massa bahan dengan volume pelarut 20 g:250 mL dengan waktu 30 menit.

2013 ◽  
pp. 71-75
Author(s):  
Zoltán Balla

The biomass is such a row material that is available in large quantities and it can be utilizied by the biotechnology in the future. Nowadays the technology which can process ligno cellulose and break down into fermentable sugars is being researched. One possible field of use of biomass is the liquid fuel production such as ethanol production. Based on the literary life cycle analysis, I compared the starch-based (first generation) to cellulose-based (second generation) bioethanol production in my study considering into account various environmental factors (land use, raw material production, energy balance). After my examination I came to the conclusion that the use of bioethanol, independent of its production technology, is favorable from environmental point of view but the application of second generation bioethanol has greater environmentally benefits.


1965 ◽  
Vol 97 (12) ◽  
pp. 1303-1318 ◽  
Author(s):  
H. J. Herbert

AbstractIn Nova Scotia one leaf cluster with an adjoining 1 inch of twig taken from the inside of each of 10 apple trees replicated four times is an adequate sample unit to measure the density of the brown mite.The brown mite has one generation with a partial second in some orchards and one with a partial second and partial third in others. The first generation adults in the bivoltine and trivoltine populations lay summer eggs on the leaves and twigs, and diapause eggs on tin twigs. The second generation adults in the bivoltine populations lay only diapause eggs; in the trivoltine populations they lay both summer and diapause eggs. The adults of the third generation lay only diapause eggs.The brown mite is found on both the leaves and woody parts of the tree. In orchards with bivoltine populations the proportion of mites on leaves reached a peak of 80% by mid-July, but thereafter gradually decreased to 10% by the end of August. However, in orchards with trivoltine populations the proportion of mites on leaves reached a peak of 80 to 90% by mid-July, remained constant until mid-August, and thereafter decreased to approximately 40% by the end of August.The number of diapause eggs laid by adults of each generation in both the bivoltine and trivoltine populations varies widely. The eggs are deposited on the trunk as well as on the branches, with the heaviest deposition in the central area of the tree. The diapause eggs laid by adults of the first generation are the last to hatch and those laid by the third generation are the first to hatch the following spring.The factors responsible for the differences in the number of generations and in the number of diapause eggs laid are unknown.


REAKTOR ◽  
2019 ◽  
Vol 19 (3) ◽  
pp. 101-110
Author(s):  
Dian Burhani ◽  
Eka Triwahyuni ◽  
Ruby Setiawan

Butanol, a rising star in biofuel, can be produced by two approaches, petrochemically and biologically. Currently, the most promising route for butanol production is by fermentation using Clostridium species through an anaerobic condition. However, similar to other biofuels, feedstock has greatly influenced the production of biobutanol and the search for inexpensive and abundant raw material is an absolute requirement for a cost-effective process. Second-generation biobutanol which is produced from lignocellulosic biomass of agricultural and forestry waste not only meets the requirement but also alleviates competition with food crops and thereby solves the problems of food scarcity from the first generation biobutanol. This paper delivered the latest and update information regarding biobutanol production specifically second-generation biobutanol in terms of production method, recovery, purification, status, and technoeconomic.  Keyword: biobutanol, lignocellulose, purification, recovery, technoeconomic


2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Forough Nazarpour ◽  
Dzulkefly Kuang Abdullah ◽  
Norhafizah Abdullah ◽  
Nazila Motedayen ◽  
Reza Zamiri

Rubberwood (Hevea brasiliensis), a potential raw material for bioethanol production due to its high cellulose content, was used as a novel feedstock for enzymatic hydrolysis and bioethanol production using biological pretreatment. To improve ethanol production, rubberwood was pretreated with white rot fungusCeriporiopsis subvermisporato increase fermentation efficiency. The effects of particle size of rubberwood (1 mm, 0.5 mm, and 0.25 mm) and pretreatment time on the biological pretreatment were first determined by chemical analysis and X-ray diffraction and their best condition obtained with 1 mm particle size and 90 days pretreatment. Further morphological study on rubberwood with 1 mm particle size pretreated by fungus was performed by FT-IR spectra analysis and SEM observation and the result indicated the ability of this fungus for pretreatment. A study on enzymatic hydrolysis resulted in an increased sugar yield of 27.67% as compared with untreated rubberwood (2.88%). The maximum ethanol concentration and yield were 17.9 g/L and 53% yield, respectively, after 120 hours. The results obtained demonstrate that rubberwood pretreated byC. subvermisporacan be used as an alternative material for the enzymatic hydrolysis and bioethanol production.


2013 ◽  
Vol 109 ◽  
pp. 84-89 ◽  
Author(s):  
Marina O.S. Dias ◽  
Tassia L. Junqueira ◽  
Carlos Eduardo V. Rossell ◽  
Rubens Maciel Filho ◽  
Antonio Bonomi

2014 ◽  
Vol 153 (5) ◽  
pp. 853-861
Author(s):  
C. E. VLACHOS ◽  
N. A. MARIOLIS ◽  
G. N. SKARACIS

SUMMARYAccording to the EU 28/2009 directive, member states are mandated to substitute 10% of fossil fuels used in transportation with biofuels by the year 2020. Bioethanol production is expected to contribute significantly towards fulfilling Greece's obligations. First-generation bioethanol, produced from amylaceous and sugar crops, is the most important biofuel globally. Maize (Zea mays L.) is the main feedstock for production worldwide, while sweet sorghum (Sorghum bicolor L. Moench), although a promising raw material source, has not yet enjoyed substantial commercial exploitation due to the high seasonality of the crop. Sustainability criteria set by the EU constitute a key factor in the characterization and future use of biofuels. A 3-year study including 20 maize and 4 sweet sorghum varieties was conducted in order to compare these two crops in terms of emitted greenhouse gases (GHG) during the cultivation phase as well as regarding emission savings by substituting bioethanol for petrol/gasoline. Both crops demonstrated promising bioethanol yields reaching 5235·7 and 6443·7 l/ha/yr for maize and sweet sorghum, respectively, and showed that they could be employed towards first-generation bioethanol production in Greece. Sweet sorghum varieties produced higher bioethanol yields per hectare coupled with lower emissions during the cultivation phase and better overall GHG savings compared to maize.


Author(s):  
В.И. Щуров ◽  
А.С. Замотайлов

Развитие первой генерации Corythucha arcuata в предгорьях и низкогорьях Северо-Западного Кавказа начинается в первых числах мая. При нижнем пороге пост-диапаузного развития имаго +11°С и при естественной длине дня ей требуется не менее 43 суток (аккумуляция 333-404 гр.-дн.). Гибель перезимовавших самок в этой зоне наблюдается к концу июня, совпадая с сокращением общей доли самок до 2-7%. В высокогорьях перезимовавшие имаго расселяются и в июне, доживая до июля на ивах и березах. Пик выхода имаго первого поколения приходится на конец июня. Массовая яйцекладка самками первого поколения (начало второго поколения) предваряется миграцией оплодотворенных самок на новые кормовые растения. Развитие преимагиальных стадий второго поколения (без смены кормовых растений) протекает с середины июня. Метаморфоз длится не менее 16-23 суток (361-430 гр.-дн.). Пик выхода имаго второго поколения в конце июля совпадает с массовым расселением, в котором всегда преобладают самки. Третье поколение развивается в августе. Метаморфоз занимает 19-28 суток (329-350 гр.-дн.). Пик выхода имаго третьего поколения приходится на первую декаду сентября. Его предваряет более ранний выход самцов, определяемый по их локальным и региональным миграциями с конца августа. Четвертое поколение является факультативным и развивается (без смены кормовых растений) с конца августа до третьей декады сентября. Развитие преимагиальных стадий этого поколения занимает не менее 26 суток (378 гр.-дн.). Последняя миграция клопов наблюдается в начале-середине октября. Самки третьего поколения первыми уходят в места зимовки в предгорьях и низкогорьях уже в середине сентября. Здесь, в дубовых лесах, зимуют имаго третьего и четвертого поколений обычно с преобладанием самок. В среднегорьях с ними могут зимовать особи-иммигранты второго поколения, но с преобладанием самцов, сохраняющимся с сентября. Development of the first generation of Corythucha arcuata in the climate of the foothills and lowlands of the Northwest Caucasus starts in the early May. With a natural day length and the threshold for post-diapause imago development of 11 °C, it requires 333-404 degree-days and at least 43 days. The death of the overwintered females in this zone is observed by the end of June, coinciding with the reduction of the total portion of females to 2-7%. In the highlands imagoes are dispersing in June as well, surviving until July on willows and birch trees. Peak of the first-generation imago outcome occurs at the end of June. Migration of fertilized females of the first generation to new forage plants is followed by mass egg laying (i.e. beginning of the second generation). During the formation of large nests in the foothills, the flight of bugs is observed even in treeless highlands. Development of the preadult stages of the second generation (without changing feed plants) takes place starting at mid-June. Metamorphosis requires 361-430 degree-days and takes at least 16-23 days. The peak of the emergence of the second generation imagoes at the end of July coincides with their dispersal, which is also dominated by females. The third generation develops in August. It requires 329-350 degree-days and takes 19-28 days. The peak of the emergence of the G3 imagoes falls on the first third of September. It is preceded by anearlier emergence of males, determined by their mass local and regional migrations since the end of August. The fourth generation is obligated and develops (without changing feed plants) from the end of August to the end of September. It requires at least 378 degree-days and takes at least 26 days. Late nymphs resulting from female immigrant of the third generation (on new trees) give imagoes only by mid-October. The last migration of bugs is observed in early to mid-October. Imagoes of the third and fourth generations with the predominance of females hibernate in the oak forests of the foothills and low-mountain. In the midlands they may be accompanied by the overwintering immigrants of the second generation, with the predominance of males, formed in September.


HortScience ◽  
2000 ◽  
Vol 35 (3) ◽  
pp. 416E-417
Author(s):  
Norberto Maciel ◽  
Richard A. Criley

Heliconia rostrata is a herbaceous-musoid sympodial rhizomatous plant that grows as clump. After three leaves are produced, each shoot of the clump may bear an inflorescence if it is induced by short days (SD). However, the relationship between shoot density and flowering has not been quantified. To evaluate the effects of the inductive period, number of shoots, and leaf removal on flowering, rhizomes were planted in 120 pots (8 L). One-third of the pots were planted with two rhizomes, while the remainder was planted with one. One-half of the pots with one rhizome were allowed to develop all their shoots for three generations, while in the remaining pots only one shoot per generation was allowed to grow. In addition, one-half of the plants in all the treatments were subjected to selective leaf removal. The plants were grown under long days (LD) >13 h in a glasshouse until four leaves were produced. Inductive SD was supplied to all the plants from 5:00 pm to 8:00 am. After 8 weeks of SD, one-half of the plants were given LD, while the other half continued under SD (conSD) until flowering. The highest percentage of flowering shoots (39% to 35%) was observed in plants under conSD; plants under SD-LD were 10% to 9%. The second generation of shoots showed the highest flowering (74% conSD and 21% SD-LD), followed by the first (62% conSD and 18% SD-LD), and third (31% conSD and 0% SD-LD) generations. Non-flowering shoots of the first generation were aborted or dead. Shoots of the third were still vegetative, since they had few leaves to be induced. Fewer flowers occurred in clumps allowed to develop all their shoots. Intact plants from rhizomes with one shoot per generation flowered more than the partially defoliated ones under conSD.


2012 ◽  
Vol 2012 ◽  
pp. 1-7
Author(s):  
Anna Pérez-Beloborodova ◽  
Adriana Artiles-Valor ◽  
Lourdes Pérez-Jar ◽  
Damir Hernández-Martínez ◽  
Missael Guerra-Aznay ◽  
...  

Four microsatellite loci were used to achieve genetic characterization of six stocks fromLitopenaeus vannameiused for aquaculture in Cuba: second generation from first introduction (S2-1), first generation from the second one (S1-2), from the third one (S1-3), and the fourth one (S1-4) and the crossings from two parental population: first generation from the first with first generation from the third (S1-1 × S1-3) and first generation from the second with first generation from the third (S1-2 × S1-3). 66% (16/24) of genetic systems in total loci were in genetic disequilibrium. The four microsatellite loci were polymorphic for all six stocks. Major quantities of allelic variants correspond to locus Pvan 1758, which is at the same time that one where there are private alleles from first generation of the third. All Fst comparisons were significant. This indicates big differences between stocks. The highest values are those in which there is presence of the second introduction. This introduction and its descendants are also more consanguineous.


2009 ◽  
Vol 83 (3) ◽  
pp. 245-254 ◽  
Author(s):  
D. Rondelaud ◽  
M. Belfaiza ◽  
P. Vignoles ◽  
M. Moncef ◽  
G. Dreyfuss

AbstractAn update on the redial generations ofFasciola hepaticawas carried out to highlight the different developmental patterns of rediae, the effects of some factors on these generations, and the consequences of such developmental patterns on cercarial productivity. The development of generations is dependent on the behaviour of the first mother redia of the first generation. If this redia remains alive throughout snail infection, it produces most second-generation rediae. In contrast, if it dies during the first weeks, daughter redia formation is ensured by a substitute redia (the second mother redia of the first generation, or the first redia of the second generation). Environmental and biotic factors do not modify the succession of redial generations, but most act by limiting the numbers of rediae, either in all generations, or in the second and/or third generations. An abnormal development of rediae reduces the number of cercariae and most are formed by the second cohort of the first generation. By contrast, most cercariae are produced by the first cohort of the second generation when redial development is normal. The mother rediae described by previous authors might correspond to the first generation and the second cohort of the second generation, while daughter rediae would be the second cohort of the second generation and the first cohort of the third generation. Under certain circumstances, daughter redia formation is ensured by the first two mother rediae or all first-generation rediae, thus demonstrating that the first mother redia is not the only larva to ensure daughter redia formation.


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