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Records with Subject: Biosystems
Showing records 1 to 25 of 185. [First] Page: 1 2 3 4 5 Last
Integrated Bioethanol Fermentation/Anaerobic Digestion for Valorization of Sugar Beet Pulp
Joanna Berlowska, Katarzyna Pielech-Przybylska, Maria Balcerek, Weronika Cieciura, Sebastian Borowski, Dorota Kregiel
December 10, 2019 (v1)
Subject: Biosystems
Keywords: bioethanol, Hydrogen, hydrolysis, methane, stillage, sugar beet pulp
Large amounts of waste biomass are generated in sugar factories from the processing of sugar beets. After diffusion with hot water to draw the sugar from the beet pieces, a wet material remains called pulp. In this study, waste sugar beet pulp biomass was enzymatically depolymerized, and the obtained hydrolyzates were subjected to fermentation processes. Bioethanol, biomethane, and biohydrogen were produced directly from the substrate or in combined mode. Stillage, a distillery by-product, was used as a feedstock for anaerobic digestion. During biosynthesis of ethanol, most of the carbohydrates released from the sugar beet pulp were utilized by a co-culture of Saccharomyces cerevisiae Ethanol Red, and Scheffersomyces stipitis LOCK0047 giving 12.6 g/L of ethanol. Stillage containing unfermented sugars (mainly arabinose, galactose and raffinose) was found to be a good substrate for methane production (444 dm³ CH₄/kg volatile solids (VS)). Better results were achieved with this medium tha... [more]
Predicting the Longitudinally and Radially Varying Gut Microbiota Composition using Multi-Scale Microbial Metabolic Modeling
Siu H. J. Chan, Elliot S. Friedman, Gary D. Wu, Costas D. Maranas
December 10, 2019 (v1)
Subject: Biosystems
Keywords: genome-scale metabolic model, gut microbiome, multi-scale modeling, spatial heterogeneity
Background: The gut microbiota is a heterogeneous group of microbes that is spatially distributed along various sections of the intestines and across the mucosa and lumen in each section. Understanding the dynamics between the spatially differential microbial populations and the driving forces for the observed spatial organization will provide valuable insights into important questions such as the nature of colonization of the infant gut and different types of inflammatory bowel disease localized in different regions of the intestines. However, in most studies, the microbiota is sampled only at a single site (often feces) or from a particular anatomical site of the intestines. Differential oxygen availability is putatively a key factor shaping the spatial organization. Results: To test this hypothesis, we constructed a community genome-scale metabolic model consisting of representative organisms for the major phyla present in the human gut microbiome. By solving step-wise optimization... [more]
Detoxification of a Lignocellulosic Waste from a Pulp Mill to Enhance Its Fermentation Prospects
Tamara Llano, Natalia Quijorna, Alberto Coz
December 10, 2019 (v1)
Subject: Biosystems
Keywords: biorefinery, detoxification, Fermentation, inhibitors, spent sulfite liquor, sugars
Detoxification is required for sugar bioconversion and hydrolyzate valorization within the biorefining concept for biofuel or bio-product production. In this work, the spent sulfite liquor, which is the main residue provided from a pulp mill, has been detoxified. Evaporation, overliming, ionic exchange resins, and adsorption with activated carbon or black carbon were considered to separate the sugars from the inhibitors in the lignocellulosic residue. Effectiveness in terms of total and individual inhibitor removals, sugar losses and sugar-to-inhibitor removal ratio was determined. The best results were found using the cation exchange Dowex 50WX2 resin in series with the anion exchange Amberlite IRA-96 resin, which resulted in sugar losses of 24.2% with inhibitor removal of 71.3% of lignosulfonates, 84.8% of phenolics, 82.2% acetic acid, and 100% of furfurals. Apart from exchange resins, the results of evaporation, overliming, adsorption with activated carbon and adsorption with black... [more]
Effects of Biogas Substrate Recirculation on Methane Yield and Efficiency of a Liquid-Manure-Based Biogas Plant
Frauke P. C. Müller, Gerd-Christian Maack, Wolfgang Buescher
December 10, 2019 (v1)
Subject: Biosystems
Keywords: biogas, hydraulic retention time (HRT), methane output, organic loading rate (OLR), recirculation
Biogas plants are the most complex systems and are heavily studied in the field of renewable energy. A biogas system is mainly influenced by biological and technical parameters that strongly interact with each other. One recommended practice when operating a biogas plant is the recirculation of the substrate from the second fermenter into the first fermenter, which extends the recirculation amount (RA) and, in turn, the recirculation rate (RR). This technique should be applied to support and secure the biogas process. In this investigation, the RA was varied, starting with the recommended “best practice” of 10.0 m³/d (RR 40%). Every ten days, the RA was reduced in steps of 1.5 m³/d, with 5.5 m³/d (RR 27%) being the final value. The basic question to be addressed concerns to what extent the RR influences the methane yield and thereby influence the efficiency of a manure-based biogas plant in practice. Diverting the “best practice” to a RR of 27% stabilised the fermentation process and l... [more]
High-Titer Methane from Organosolv-Pretreated Spruce and Birch
Leonidas Matsakas, Christos Nitsos, Dimitrij Vörös, Ulrika Rova, Paul Christakopoulos
December 10, 2019 (v1)
Subject: Biosystems
Keywords: anaerobic digestion, biogas, birch, lignocellulosic biomass, methane, organosolv pretreatment, spruce
The negative impact of fossil fuels and the increased demand for renewable energy sources has led to the use of novel raw material sources. Lignocellulosic biomass could serve as a possible raw material for anaerobic digestion and production of biogas. This work is aimed at using forest biomass, both softwood (spruce) and hardwood (birch), as a raw material for anaerobic digestion. We examined the effect of different operational conditions for the organosolv pretreatment (ethanol content, duration of treatment, and addition of acid catalyst) on the methane yield. In addition, we investigated the effect of addition of cellulolytic enzymes during the digestion. We found that inclusion of an acid catalyst during organosolv pretreatment improved the yields from spruce, but it did not affect the yields from birch. Shorter duration of treatment was advantageous with both materials. Methane yields from spruce were higher with lower ethanol content whereas higher ethanol content was more benef... [more]
LC-ESI-QTOF/MS Profiling of Australian Mango Peel By-Product Polyphenols and Their Potential Antioxidant Activities
Danying Peng, Hafza Fasiha Zahid, Said Ajlouni, Frank R. Dunshea, Hafiz A. R. Suleria
December 10, 2019 (v1)
Subject: Biosystems
Keywords: antioxidant activity, HPLC-PDA, LC-ESI-QTOF/MS, mango peels, polyphenols
Mango (Mangifera indica L.) is one of the most important fruits in the world. Mango peel is an important by-product that is rich in polyphenols and it could have high economic value if it is effectively utilized. Phenolic characterization is an essential step in the commercial utilization of mango peel by-products as food ingredients. Herein, qualitative and quantitative analyses of two Australian mango peel “Keitt” and “Kensington Pride” (K&P) by-products were conducted while using liquid chromatography coupled to electrospray ionisation and quadrupole time of flight mass spectrometry (LC-ESI-QTOF/MS) and high-performance liquid chromatography coupled to photodiode array detector (HPLC-PDA). A total of 98 polyphenols compounds were tentatively identified in both Keitt peel and K&P peel extracts, with greater concentrations of these compounds being detected in Keitt peel. The total phenolic content (TPC), total flavonoid content (TFC), and a total tannin content (TTC) were determined.... [more]
Effect of Enzyme Interaction with Lignin Isolated from Pretreated Miscanthus × giganteus on Cellulolytic Efficiency
Woochul Jung, Ratna Sharma-Shivappa, Praveen Kolar
December 10, 2019 (v1)
Subject: Biosystems
Keywords: hydrolysis, inhibition, lignin, miscanthus, pretreatment
The effect of binding between the lignin isolates from an alkali (NaOH)− and an acid (H2SO4)− pretreated Miscanthus and cellulolytic enzymes in Cellic® CTec2 was investigated. Additonally, cellobiose and Avicel were enzymatically hydrolyzed with and without lignin isolates to study how enzyme binding onto lignin affects its conversion to glucose. Three carbohydrate−lignin loadings (0.5:0.25, 0.5:0.5, and 0.5:1.0% (w/v)) were employed. The results indicated that β-glucosidase (BG) had a strong tendency to bind to all lignin isolates. The overall tendency of enzyme binding onto lignin isolate was similar regardless of pretreatment chemical concentration. Though enzyme binding onto lignin isolates was observed, hydrolysis in the presence of these isolates did not have a significant (p > 0.05) impact on glucose production from cellobiose and Avicel. Cellobiose to glucose conversion of 99% was achieved via hydrolysis at both 5 and 10 FPU/g carbohydrate. Hydrolysis of Avicel with 5 and 10 FP... [more]
Ultrasound-Assisted Phytochemical Extraction Condition Optimization Using Response Surface Methodology from Perlette Grapes (Vitis vinifera)
Muhammad Kaleem, Asif Ahmad, Rai Muhammad Amir, Ghazala Kaukab Raja
December 10, 2019 (v1)
Subject: Biosystems
Keywords: antioxidants, flavonoids, phytochemicals, ultrasound, Vitis vinifera
In the current study, bioactive compounds of Vitis vinifera (Perlette) were extracted using an ultrasound-assisted extraction technique. The central composite design of response surface methodology (RSM) was used to determine the effect of time, temperature, and concentration of acetic acid on response variables that include extract yield, total phenolic content (TPC), total flavonoid content (TFC), and antioxidant activity of Vitis vinifera extracts. The results of the central composite design of RSM revealed that the quadratic polynomial model is best fitted to experimental results, with all the responses having a regression coefficient greater than 0.9. Optimized extraction levels include 26.5 min, an extraction temperature of 59 °C, and an acetic acid concentration of 62.9% with good extraction yield results of 34.95 g/100 g dry weight (DW) of grapes, TPC 34.38 mg gallic acid equivalent per gram (GAE/g) DW, flavonoid content 10.21 mg quercetin equivalents per gram (QEQ/g) DW, and a... [more]
Stimuli-Sensitive Cell Penetrating Peptide-Modified Nanocarriers
Federico Perche
December 10, 2019 (v1)
Subject: Biosystems
Keywords: cellular uptake, peptides, responsive
The integration of drugs into nanocarriers favorably altered their pharmacodynamics and pharmacokinetics compared to free drugs, and increased their therapeutic index. However, selective cellular internalization in diseased tissues rather than normal tissues still presents a formidable challenge. In this chapter I will cover solutions involving environment-responsive cell-penetrating peptides (CPPs). I will discuss properties of CPPs as universal cellular uptake enhancers, and the modifications imparted to CPP-modified nanocarriers to confine CPP activation to diseased tissues.
Production Process and Optimization of Solid Bioethanol from Empty Fruit Bunches of Palm Oil Using Response Surface Methodology
Nurfahmi, M. Mofijur, Hwai Chyuan Ong, Badrul Mohamed Jan, Fitranto Kusumo, Abdi Hanra Sebayang, Hazlina Husin, Arridina Susan Silitonga, Teuku Meurah Indra Mahlia, S. M. Ashrafur Rahman
December 10, 2019 (v1)
Subject: Biosystems
Keywords: bioethanol production, calorific value, enzyme hydrolysis, organosolv pretreatment, response surface methodology, solid bioethanol
This study aimed to observe the potential of solid bioethanol as an alternative fuel with high caloric value. The solid bioethanol was produced from liquid bioethanol, which was obtained from the synthesis of oil palm empty fruit bunches (PEFBs) through the delignification process by using organosolv pretreatment and enzymatic hydrolysis. Enzymatic hydrolysis was conducted using enzyme (60 FPUg−1 of cellulose) at a variety of temperatures (35 °C, 70 °C, and 90 °C) and reaction times (2, 6, 12, 18, and 24 h) in order to obtain a high sugar yield. The highest sugars were yielded at the temperature of 90 °C for 48 h (152.51 mg/L). Furthermore, fermentation was conducted using Saccharomyces cerevisiae. The bioethanol yield after fermentation was 62.29 mg/L. Bioethanol was extracted by distillation process to obtain solid bioethanol. The solid bioethanol was produced by using stearic acid as the additive. In order to get high-quality solid bioethanol, the calorific value was optimized using... [more]
Antibacterial and Antifungal Activity of Novel Synthesized Neodymium-Substituted Cobalt Ferrite Nanoparticles for Biomedical Application
Suriya Rehman, Mohammad Azam Ansari, Mohammad A. Alzohairy, Mohammad N. Alomary, B. Rabindran Jermy, Raheem Shahzad, Neda Tashkandi, Zainab Hassan Alsalem
December 10, 2019 (v1)
Subject: Biosystems
Keywords: antibacterial activity, bioactivity, magnetic nanomaterials, neodymium, spinel ferrites, yeast
Neodymium (Nd)-substituted cobalt ferrite nanoparticles (NPs), i.e., CoNdxFe2−xO4 (0.0 ≤ x ≤ 0.2) NPs, were synthesized by the sonochemical method. The compositional characterization was done by scanning electron microscopy (SEM) equipped with energy-dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). Antistaphylococcal activity was found to be enhanced, i.e., survival rate was 50%, 45%, 40%, and 30% with the increase in the ratio of Nd (0.0 ≤ x ≤ 0.2), whereas anticandidal activity was found efficient, i.e., 9%, 20%, 22%, and 40% survival rate at all the four ratios. The morphogenesis studies indicated that the synthesized metal−ligand, improves the antimicrobial capacity by binding them strongly to the microbial walls. To the best of our knowledge, this is the first report which demonstrates the series of CoNdxFe2−xO4 (0.0 ≤ x ≤ 0.2) NPs being active towards Staphylococcus aureus and Candida albicans and encourages its potential candidature for pharmaceuti... [more]
Chemically Enhanced Primary Sludge as an Anaerobic Co-Digestion Additive for Biogas Production from Food Waste
Xiaorong Kang, Yali Liu
December 9, 2019 (v1)
Subject: Biosystems
Keywords: chemically enhanced primary sedimentation, food waste, Renewable and Sustainable Energy, VFAs
In order to overcome process instability and buffer deficiency in the anaerobic digestion of mono food waste (FW), chemically enhanced primary sludge (CEPS) was selected as a co-substrate for FW treatment. In this study, batch tests were conducted to study the effects of CEPS/FW ratios on anaerobic co-digestion (coAD) performances. Both soluble chemical oxygen demand (SCOD) and protease activity were decreased, with the CEPS/FW mass ratio increasing from 0:5 to 5:0. However, it was also found that the accumulation of volatile fatty acids (VFAs) was eliminated by increasing the CEPS/FW ratio, and that corresponding VFAs concentrations decreased from 13,872.97 to 1789.98 mg chemical oxygen demand per L (mg COD/L). In addition, the maximum value of cumulative biogas yield (446.39 mL per g volatile solids removal (mL/g VSsremoval)) was observed at a CEPS/FW ratio of 4:1, and that the tendency of coenzyme F420 activity was similar to biogas production. The mechanism analysis indicated that... [more]
A Comparative Study of Biogas Reactor Fluid Rheology—Implications for Mixing Profile and Power Demand
Luka Šafarič, Sepehr Shakeri Yekta, Jörgen Ejlertsson, Mohammad Safari, Hossein Nadali Najafabadi, Anna Karlsson, Francesco Ometto, Bo H. Svensson, Annika Björn
December 9, 2019 (v1)
Subject: Biosystems
Keywords: anaerobic digestion, Computational Fluid Dynamics, stirring, substrate, viscosity
Anaerobic digestion (AD) is an established process for integrating waste management with renewable energy and nutrient recovery. Much of the research in this field focuses on the utilisation of new substrates, yet their effects on operational aspects such as fluid behaviour and power requirement for mixing are commonly overlooked, despite their importance for process optimisation. This study analysed rheological characteristics of samples from 21 laboratory-scale continuous stirred-tank biogas reactors (CSTBRs) digesting a range of substrates, in order to evaluate substrate effect on mixing efficiency and power demand through computational fluid dynamics (CFD). The results show that substrate and process parameters, such as solids content and organic loading, all have a significant effect on CSTBR fluid rheology. The correlation levels between rheological and process parameters were different across substrates, while no specific fluid behaviour patterns could be associated with substra... [more]
Antifungal Activity of Euclea divinorum Root and Study of its Ethnobotany and Phytopharmacology
Mohamed Al-Fatimi
December 9, 2019 (v1)
Subject: Biosystems
Keywords: antifungal, antioxidant, ethnobotany, Euclea divinorum, naphthoquinones, Soqotra
The ethnobotanical survey of Euclea divinorum Hiern (Ebenaceae) was conducted on Soqotra Island, Yemen. The root bark is used to treat mouth, dental, dermal and blood diseases in the traditional medicine of the island. The study is the first report about the effect of the plant root barks against six human pathogenic fungi. The non-polar dichloromethane extract of Euclea divinorum root bark showed stronger antifungal activities compared to polar direct and sequential methanolic extracts. These extracts showed significant broad antifungal activity against Absidia corymbifera, Aspergillus fumigatus, Candida krusei, Microsporum gypseum, Mucor sp. and Trichophyton mentagrophytes compared to the standard antibiotic drug nystatin. Thin-layer chromatography (TLC) revealed the presence of the naphthoquinones in the extracts. The results showed an extraction process to separate most antifungal naphthoquinones from the root bark by using non-polar solvent dichloromethane, while flavonoids remain... [more]
Effects of Conventional Flotation Frothers on the Population of Mesophilic Microorganisms in Different Cultures
Mohammad Jafari, Mehdi Golzadeh, Sied Ziaedin Shafaei, Hadi Abdollahi, Mahdi Gharabaghi, Saeed Chehreh Chelgani
December 3, 2019 (v1)
Subject: Biosystems
Keywords: bioleaching, flotation, frother, Machine Learning, mixed culture
Bioleaching is an environment-friendly and low-investment process for the extraction of metals from flotation concentrate. Surfactants such as collectors and frothers are widely used in the flotation process. These chemical reagents may have inhibitory effects on the activity of microorganisms through a bioleaching process; however, there is no report indicating influences of reagents on the activity of microorganisms in the mixed culture which is mostly used in the industry. In this investigation, influences of typical flotation frothers (methyl isobutyl carbinol and pine oil) in different concentrations (0.01, 0.10, and 1.00 g/L) were examined on activates of bacteria in the mesophilic mixed culture (Acidithiobacillus ferrooxidans, Leptospirillum ferrooxidans, and Acidithiobacillus thiooxidans). For comparison purposes, experiments were repeated by pure cultures of Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans in the same conditions. Results indicated that increasing... [more]
Enhancement of Bacillus subtilis Growth and Sporulation by Two-Stage Solid-State Fermentation Strategy
Zhi-Min Zhao, Jun-Ting Xi, Ji-Fei Xu, Li-Tong Ma, Ji Zhao
December 3, 2019 (v1)
Subject: Biosystems
Keywords: agro-industrial residues, Bacillus subtilis, low-field nuclear magnetic resonance (LF-NMR), microbial ecological agents, solid-state fermentation, sporulation
Two-stage solid-state fermentation strategy was exploited and systematically optimized to enhance Bacillus subtilis growth and sporulation for increasing effective cell number in B. subtilis microbial ecological agents. The first stage focused on improving cell growth followed by the second stage aiming to enhance both cell growth and sporulation. The optimal fermentation condition was that temperature changed from 37 °C to 47 °C at a fermentation time of 48 h and Mn2+ content in medium was 4.9 mg MnSO4/g dry medium. Solid medium properties were improved by the optimal two-stage fermentation. HPLC results demonstrated that glucose utilization was facilitated and low-field nuclear magnetic resonance (LF-NMR) results showed that more active sites in medium for microbial cells were generated during the optimal two-stage fermentation. Moreover, microbial growth and sporulation were enhanced simultaneously during the second stage of fermentation through delaying microbial decline phase and... [more]
Techno-Economic Analysis and Physicochemical Properties of Ceiba pentandra as Second-Generation Biodiesel Based on ASTM D6751 and EN 14214
N.A.M. Jamaluddin, Teuku Meurah Indra Riayatsyah, Arridina Susan Silitonga, M. Mofijur, Abd Halim Shamsuddin, Hwai Chyuan Ong, Teuku Meurah Indra Mahlia, S.M. Ashrafur Rahman
November 24, 2019 (v1)
Subject: Biosystems
Keywords: Ceiba pentandra, non-edible oil, sensitivity analysis, techno-economic: life cycle cost
Processing biodiesel from non-edible sources of feedstock seems to be thriving in recent years. It also has also gathered more attention than in the past, mainly because the biodiesel product is renewable and emits lower pollution compared to fossil fuels. Researchers have started their work on various kinds of biodiesel product, especially from a non-edible feedstock. Non-edible feedstocks such as Ceiba pentandra show great potential in the production of biodiesel, especially in the Southeast Asia region because the plants seem to be abundant in that region. Ceiba pentandra, also known as the Kapok tree, produces hundreds of pods with a length of 15 cm (5.9 in) and diameter 2−5 cm (1−2 in). The pods consist of seeds and fluff in the surrounding areas inside the pod, which itself contains yellowish fibre, a mixture of cellulose and lignin. The seeds of Ceiba pentandra can be used as feedstock for biodiesel production. The study for Ceiba pentandra will involve techno-economic, as well... [more]
Green and Facile Synthesis of Dendritic and Branched Gold Nanoparticles by Gelatin and Investigation of Their Biocompatibility on Fibroblast Cells
Quoc Khuong Vo, My Nuong Nguyen Thi, Phuong Phong Nguyen Thi, Duy Trinh Nguyen
November 24, 2019 (v1)
Subject: Biosystems
Keywords: fibroblast cells, gelatin, nanodendrites, nanostar, one-pot synthesis
In this work, gold nanostar (AuNPs) and gold nanodendrites were synthesized by one-pot and environmentally friendly approach in the presence of gelatin. Influence of gelatin concentrations and reaction conditions on the growth of branched (AuNPs) were investigated further. Interestingly, the conversion of morphology between dendritic and branched nanostructure can be attained by changing the pH value of gelatin solution. The role of gelatin as a protecting agent through the electrostatic and steric interaction was also revealed. Branched nanoparticles were characterized by surface plasmon resonance spectroscopy (SPR), transmission electron microscopy (TEM), XRD, dynamic light scattering (DLS) and zeta-potential. The chemical interaction of gelatin with branched gold nanoparticles was analyzed by Fourier transform infrared spectroscopy (FT-IT) technique. Ultraviolet visible spectroscopy results indicated the formation of branched gold nanoparticles with the maximum surface plasmon reson... [more]
Improvement of the Quality of Ginkgo biloba Leaves Fermented by Eurotium cristatum as High Value-Added Feed
Minmin Zou, Xiaohan Guo, Yan Huang, Fuliang Cao, Erzheng Su, Jiahong Wang
November 24, 2019 (v1)
Subject: Biosystems
Keywords: active constituents, E. cristatum strain, ginkgo leaves, nutrients, solid-state fermentation
Ginkgo biloba leaves are well known for their high content of nutrients and bioactive substances. However, unpleasant smell and a small number of ginkgolic acids greatly reduce the utilization of the leaves. In this work, solid-state fermentation of G. biloba leaves using Eurotium cristatum was studied by investigation of the nutrient changes and its feasibility as a functional feed. E. cristatum could grow on pure G. biloba leaves and the addition of excipients could significantly improve the growth of E. cristatum. The optimal medium was with 10% (w/w) of whole G. biloba seeds and the optimized water content, pH, inoculum size and fermentation time were 45% (w/w), 4.5, 4.76 × 107 CFU/100 g wet medium, and eight days, respectively. Under the optimal conditions, the spore number increased by about 40 times. The content of flavonoids was greatly increased by 118.6%, and the protein and polyprenyl acetates (PPAs) were increased by 64.9% and 10.6%, respectively. The ginkgolic acids, ligni... [more]
The Performance and Exhaust Emissions of a Diesel Engine Fuelled with Calophyllum inophyllum—Palm Biodiesel
Natalina Damanik, Hwai Chyuan Ong, M. Mofijur, Chong Wen Tong, Arridina Susan Silitonga, Abd Halim Shamsuddin, Abdi Hanra Sebayang, Teuku Meurah Indra Mahlia, Chin-Tsan Wang, Jer-Huan Jang
November 24, 2019 (v1)
Subject: Biosystems
Keywords: alternative fuel, Calophyllum inophyllum biodiesel, engine performance, exhaust emissions, palm biodiesel, transesterification
Nowadays, increased interest among the scientific community to explore the Calophyllum inophyllum as alternative fuels for diesel engines is observed. This research is about using mixed Calophyllum inophyllum-palm oil biodiesel production and evaluation that biodiesel in a diesel engine. The Calophyllum inophyllum−palm oil methyl ester (CPME) is processed using the following procedure: (1) the crude Calophyllum inophyllum and palm oils are mixed at the same ratio of 50:50 volume %, (2) degumming, (3) acid-catalysed esterification, (4) purification, and (5) alkaline-catalysed transesterification. The results are indeed encouraging which satisfy the international standards, CPME shows the high heating value (37.9 MJ/kg) but lower kinematic viscosity (4.50 mm2/s) due to change the fatty acid methyl ester (FAME) composition compared to Calophyllum inophyllum methyl ester (CIME). The average results show that the blended fuels have higher Brake Specific Fuel Consumption (BSFC) and NOx emiss... [more]
Rapid Processing of Abandoned Oil Palm Trunks into Sugars and Organic Acids by Sub-Critical Water
Hazwani Ishak, Hiroyuki Yoshida, Noor Azura Muda, Mohd Halim Shah Ismail, Shamsul Izhar
November 24, 2019 (v1)
Subject: Biosystems
Keywords: hydrolysis, oil palm trunk (OPT), organic acid, subcritical water (sub-CW), sugar
Abandoned oil palm trunk (OPT) is among the most abundant left-over biomass in Malaysia and is allowed to decompose naturally in the field. However, the recycling of OPT is less considered although OPT is a bioresource that has a high potential for conversion into value-added products. In this study, waste OPT was rapidly converted by hydrolysis using subcritical water (sub-CW). This work is the first attempt to explore the utilization of waste OPT based on the differences in moisture, cellulose and hemicellulose contents in the top and bottom segments, and from various ages of the waste OPT. 21- and 35-year-old OPTs were divided into top and bottom sections. The OPTs was subjected to sub-CW at a heating rate of 3.8 °C/s at various temperatures and times. The 21-year-old OPT was superior to the 35-year-old OPT for conversion into sugar and organic acid. The yield of the total sugar was between 0.41 and 0.77 kg/kg-OPT in the bottom and top sections. The excellent correlation between the... [more]
Synthetic Effect of EDTA and Ni2+ on Methane Production and Microbial Communities in Anaerobic Digestion Process of Kitchen Wastes
Tingting Zhong, Yali Liu, Xiaorong Kang
November 24, 2019 (v1)
Subject: Biosystems
Keywords: EDTA, kitchen waste, methane, microbial community, Ni2+
Batch tests were carried out to study the effect of simultaneous addition of ethylenediaminetetraacetic acid and Ni2+ (EDTA-Ni) on anaerobic digestion (AD) performances of kitchen wastes (KWs). The results indicated that the cumulative biogas yield and methane content were enhanced to 563.82 mL/gVS and 63.7% by adding EDTA-Ni, respectively, which were almost 1.15 and 1.07-fold of that in the R2 with Ni2+ addition alone. At the same time, an obvious decrease of propionic acid was observed after EDTA-Ni addition. The speciation analysis of Ni showed that the percentages of water-soluble and exchangeable Ni were increased to 38.8% and 36.3% due to EDTA-Ni addition, respectively. Also, the high-throughput sequencing analysis revealed that the EDTA-Ni promoted the growth and metabolism of Methanosarcina and Methanobacterium, which might be the major reason for propionic acid degradation and methane production.
Study of 4,4‘-Methylene Diisocyanate Phenyl Ester-Modified Cassava Residues/Polybutylene Succinate Biodegradable Composites: Preparation and Performance Research
Lijie Huang, Hanyu Zhao, Hao Xu, Shuxiang An, Chunying Li, Chongxing Huang, Shuangfei Wang, Yang Liu, Jie Chen
November 24, 2019 (v1)
Subject: Biosystems
Keywords: 4,4’-methylene diisocyanate phenyl ester, biodegradable, cassava residues, modification, polybutylene succinate
Biomass materials have become a research focus for humankind, due to the decreasing availability of fossil fuels and the increasing release of greenhouse gas. In this work, we prepared biodegradable composites with waste cassava residues and polybutylene succinate (PBS) by modifying cassava residues using 4,4’-methylene diisocyanate phenyl ester (MDI) and tested their properties. The effects of MDI modification on the structure, mechanical properties, water absorption, microstructure, and thermal stability of the composites were studied via Fourier transform infrared spectroscopy, contact angle measurement, mechanical property testing, water absorption analysis, scanning electron microscopy, and thermogravimetric analysis, respectively. The results showed that the tensile strength and flexural strength of the material increased by 72% and 20.89%, respectively, when the MDI-modified cassava residue content was 30%. When 10% MDI-modified cassava residues were added, the tensile strength... [more]
Pulsed Electric Field-Assisted Ethanolic Extraction of Date Palm Fruits: Bioactive Compounds, Antioxidant Activity and Physicochemical Properties
Azhari Siddeeg, Muhammad Faisal Manzoor, Muhammad Haseeb Ahmad, Nazir Ahmad, Zahoor Ahmed, Muhammad Kashif Iqbal Khan, Abid Aslam Maan, Mahr-Un-Nisa, Xin-An Zeng, Al-Farga Ammar
November 24, 2019 (v1)
Subject: Biosystems
Keywords: antioxidant activity, bioactive compounds, dates, ethanolic extraction, PEF
The current study was aimed to observe the influence of pulsed electric field (PEF) on the extraction of bioactive components; antioxidant activity and physicochemical properties of date palm fruit extract (DPFE) as compared to the extract untreated by PEF. The fruit was treated with PEF (frequency: 10 Hz, time: 100 µs, pulses number: 30, electric field strength (EFS): 1, 2, and 3 kV/cm. The results show that PEF has a positive impact on the total content of carotenoids, anthocyanins, flavonoids, and phenolics by increasing the EFS. DPFE treated with PEF exhibit a strong antioxidant activity as compared to untreated extract, while electrical conductivity, pH values, and titratable acidity were not affected by PEF. The results indicate a notable increase in the volatile components in DPFE treated with PEF at 3 kV/cm. Thus, PEF treatment can assist the ethanolic extraction of DPFE to improve the bioactivity and antioxidative activity. These findings suggest that PEF can be a more suitabl... [more]
Effect of Hydrothermal Pretreatment on Volatile Fatty Acids Production from Source-Separated Organics
Farokh laqa Kakar, Ehssan Hosseini Koupaie, Hisham Hafez, Elsayed Elbeshbishy
November 24, 2019 (v1)
Subject: Biosystems
Keywords: acidification, dark fermentation, hydrothermal pretreatment, source-separated organics, volatile fatty acids
The current study investigates the effect of hydrothermal pretreatment (HTP) on acidification of source-separated organics (SSO) in terms of volatile fatty acids (VFAs) production and solubilization. Temperature and retention time for HTP of SSO ranged from 150 to 240 °C and 5 to 30 min, respectively. The soluble substance after hydrothermal pretreatment initially increased, reaching its peak at 210 °C and then declined gradually. The highest overall chemical oxygen demand (COD) solubilization of 63% was observed at “210 °C-20 min” compared to 17% for raw SSO. The highest VFAs yield of 1536 mg VFAs/g VSS added was observed at “210 °C-20 min” compared to 768 mg VFAs/g VSS for raw SSO. Intensification of hydrothermal pretreatment temperature beyond 210 °C resulted in the mineralization of the organics and adversely affected the process.
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