N. Qureshi

• PhD, PhD [Fellow American Institute of Chemical Engineers (FAIChE)]
• Supervisory Scientist at United States Department of Agriculture

Butyric acid, a four-carbon fatty acid, is an important industrial chemical and feedstock. To produce this chemical, a control fermentation was run with a 126.5 g.L−1 glucose concentration in the feed medium. In this medium, the strain produced 44.8 g.L−1 total acid with a productivity of 0.23 g.L−1h−1 and a yield of 0.41 g.g−1. The strain (Clostri...

Presently, the world faces pressing global challenges encompassing social, economic, and sustainable development, all of which demand a growing scale of energy production and associated services. With abundant waste biomass at our disposal, there exists immense potential for harnessing it to produce biofuels. In this study, we synthesized biodiesel...

Clostridium tyrobutyricum strain NRRL B-67062 was previously isolated from an ethanol production facility and shown to produce high yields of butyric acid. In addition, the cell-free supernatant of the fermentation broth from NRRL B-67062 contained antibacterial activity against certain Gram-positive bacteria. To determine the source of this antiba...

Clostridium tyrobutyricum strain NRRL B-67062 was previously isolated from an ethanol production facility and shown to produce high yields of butyric acid. In addition, the cell-free supernatant of the fermentation broth from NRRL B-67062 contained antibacterial activity against certain Gram-positive bacteria. To determine the source of this antiba...

Presently, the world faces pressing global challenges encompassing social, economic, and sustainable development , all of which demand a growing scale of energy production and associated services. With abundant waste biomass at our disposal, there exists immense potential for harnessing it to produce biofuels. In this study, we synthesized biodiese...

This study applied concentrated xylose (60–250 g/L) medium to produce butanol (acetone butanol ethanol, or ABE). A control batch fermentation of 61 g/L initial glucose using Clostridium beijerinckii P260 resulted in a productivity and yield of 0.33 g/L·h and 0.43 g/g, respectively. Use of 60 g/L xylose in a batch system resulted in productivity and...

The conversion of sugar cane bagasse (SCB) into cellulosic ethanol by microorganism becomes challenging at high solid liquid ratio (SLR) due to high concentration of inhibitors in the liquid hot water pretreatment. Therefore, this study aims to produce cellulosic ethanol by detoxifying the high SLR hydrolysate (1:6, w/v) using SY-01 resin. The deto...

The conversion of sugar cane bagasse (SCB) into cellulosic ethanol by microorganism becomes challenging at high solid liquid ratio (SLR) due to high concentration of inhibitors in the liquid hot water pretreatment. Therefore, this study aims to produce cellulosic ethanol by detoxifying the high SLR hydrolysate (1:6, w/v) using SY-01 resin. The deto...

Renewable energy sources such as biodiesel have gained attention due to their pollution free and eco-friendly nature. The use of heterogenous nanocatalyst is preferred in biodiesel production to their ease of recovery and recyclability. In this study, biodiesel was produced from nonedible Cordia dichotoma seed oil using NiO nanocatalyst. NiO nanoca...

The goal of this study was to improve resource use efficiency in agricultural systems and agro-based industries, reduce wastes that go to landfills and incinerators, and consequently, improve the economics of 2,3-butanediol (2,3-BD) production. This study evaluated the feasibility of 2,3-BD production by replacing the mineral nutrients, and buffers...

In this study, the ability of a novel strain of Clostridium tyrobutyricum NRRL 67062 to produce butyric acid during glucose fermentation was evaluated. The strain was evaluated for substrate and product inhibition in batch experiments using anaerobic tubes. To characterize glucose inhibition, initial glucose concentrations ranging from 60 to 250 g...

Milk kefir fermentation has been used in households for generations. Consumption of milk kefir has been associated with various health benefits, presumably from the probiotics of yeast and bacteria that make up the kefir grains. In addition, many of the microbes are known to produce novel antimicrobial compounds that can be used for other applicati...

The plastic disposal problem has been augmented over the years due to the surge in utilization of single-use plastics, the indiscriminate discarding of plastics, and space limitations associated with landfill sites. Therefore, in this study the biodegradable, biorenewable, and biocompatible plastic substitutes, poly(hydroxyalkanoate) (PHA) biopolym...

Itaconic acid (IA), is a versatile platform chemical that is produced by Aspergillus terreus using glucose as carbon source. Lignocellulosic biomass can be used as a low cost source of sugars for IA production. However, A. terreus does not produce IA even after 100 fold dilution from enzymatically hydrolyzed wheat straw pretreated with dilute acid....

Butanol was produced commercially from cornstarch and sugarcane molasses (renewable re-sources) until 1983 when production plants were forced to cease due to unfavorable economics of production, caused in part by escalating prices of these feedstocks. During recent years, research focus has been on the use of economically available agricultural bio...

Butanol was produced commercially from cornstarch and sugarcane molasses (renewable resources) until 1983, when production of these plants was forced to cease because of unfavorable economics of production caused in part by escalating prices of these feedstocks. During recent years, the focus of research has been on the use of economically availabl...

Biobutanol is one of the most promising renewable biofuels, which can be produced from lignocellulosic biomass by Clostridium. However, due to the dense structure of lignin, biomass is difficult to be hydrolyzed into fermentable sugars. This study has developed a short time (90 min) and low energy consumption (120 ◦C) pretreatment process using dee...

Butanol can be produced biologically through fermentation of lignocellulosic biomass-derived sugars by Gram-positive Clostridium species. For cost-effective production, increased butanol fermentation titers are desired. However, the currently available butanol-fermenting microbes do not tolerate sufficiently high butanol concentrations; thus, new b...

We previously identified specific proteins associated with ethanol stress response in a Lactobacillus buchneri strain capable of growing in 10% ethanol. In the current study, the exceptional roles of ethanol responsive genes are examined to determine if they can increase ethanol tolerance in E. coli host cells. The recombinant strains carrying etha...

Worldwide, there are various feedstocks such as straws, corn stover, sugarcane bagasse, sweet sorghum bagasse (SSB), grasses, leaves, whey permeate, household organic waste, and food waste (FW) that can be converted to valuable biofuels such as butanol. For the present studies, an economic analysis was performed to compare butanol production from t...

Major market and technological aspects related to the fermentative production of n‐butanol by Clostridia are reviewed in this chapter. In the first section various technological aspects are provided including microbial strains, substrates, bioreactors, and product recovery techniques. In the second part of the chapter, representative and recent pro...

BACKGROUND Butanol, a superior biofuel to ethanol, can be produced by fermentation of renewable feedstocks such as corn or molasses. Since costs of these feedstocks are high, this biofuel should be produced from economic substrates. Recent studies have identified yellow top (YT) (Physaria fendleri) as an economical feedstock which is currently used...

Lactobacillus buchneri and Oenococcus oeni are two unique ethanol-tolerant Gram-positive bacteria species. Genome comparison analyses revealed that L. buchneri and O. oeni possess a pntAB locus that was absent in almost all other lactic acid bacteria (LAB) genomes. Our hypothesis is that the pntAB locus contributes to the ethanol tolerance trait of...

The decreasing supply of fossil fuels and increasing environmental concern of food waste disposal have raised interests in food waste conversation to biofuels such as butanol. Apple pomace, a food processing waste rich in carbohydrates, is a good feedstock for butanol production. The goal of this study is to present and evaluate a process to thorou...

Itaconic acid (IA; a building block platform chemical) is currently produced industrially from glucose by fermentation with Aspergillus terreus. In order to expand the use of IA, its production cost must be lowered. Lignocellulosic biomass has the potential to serve as low-cost source of sugars for IA production. It was found that the fungus cannot...

Yellow Top (Physaria fendleri) is a plant that belongs to the mustard family. This plant is used to produce seeds that are rich in hydroxy oil. After extraction of oil, the presscake is land filled. The seedcake is rich in polymeric sugars and can be used for various bioconversions. For the present case, the seedcake or presscake was hydrolyzed wit...

In these studies liquid hot water (LHW) pretreated and enzymatically hydrolyzed Sweet Sorghum Bagasse (SSB) hydrolyzates were fermented in a fed‐batch reactor. As reported in the preceding paper, the culture was not able to ferment the hydrolyzate I in a batch process due to presence of high level of toxic chemicals, in particular acetic acid relea...

In these studies we pretreated sweet sorghum bagasse (SSB) using liquid hot water (LHW) or dilute H2SO4 (2 g·L⁻¹) at 190°C for zero min (as soon as temperature reached 190°C, cooling was started) to reduce generation of sugar degradation fermentation inhibiting products such as furfural and hydroxymethyl furfural (HMF). The solids loading were 250‐...

Sweet sorghum syrups represent a renewable raw material that can be available year-round for production of biofuels and biochemicals. Sweet sorghum sugars have been used as sources for butanol production in the past but most often the studies focused on sweet sorghum juice and not on sweet sorghum syrups. Therefore, we investigated the feasibility...

The pulp and paper industry produces about 300–350 million tons of paper mill sludge (PMS) annually and majority is disposed of by landfill. PMS contains up to 75% carbohydrates. In this study, PMS was treated by de-ashing, fiber regeneration and enzymatic hydrolysis. The PMS hydrolysate was used for butyric acid production by Clostridium tyrobutyr...

This article reviews bioconversion of plant materials such as wheat straw (WS), corn stover (CS), barley straw (BS), and switchgrass (SG) to butanol and process technology that converts these materials into this superior biofuel. Successful fermentation of low-value WS makes butanol fermentation economically attractive. Simultaneous hydrolysis, fer...

This article describes the use of biofilm reactors for the production of various chemicals by fermentation and wastewater treatment. Biofilm formation is a natural process where microbial cells attach to the support (adsorbent) or form flocs/aggregates (also called granules) without use of chemicals and form thick layers of cells known as "biofilms...

This article discusses the separation of butanol from aqueous solutions and/or fermentation broth by adsorption. Butanol fermentation is also known as acetone butanol ethanol (ABE) or solvent fermentation. Adsorbents such as silicalite, resins (XAD-2, XAD-4, XAD-7, XAD-8, XAD-16), bone charcoal, activated charcoal, bonopore, and polyvinylpyridine h...

This is an overview of the butanol (usually called acetone butanol ethanol, ABE) fermentation in various types of reactor systems and recovery by gas stripping. Gas stripping is a simple technique which does not require expensive apparatus, does not harm the culture, does not remove nutrients and reaction intermediates and reduces butanol toxicity...

This is an overview of butanol separation from model solutions and fermentation broth by pervaporation. It is dicult to compare di€erent authors' work on butanol separation because of the number of variables involved. These variables include type of membrane, membrane thickness, feed temperature, condensation temperature, vacuum or sweep gas, feed...

This article describes the production of butanol (acetone–butanol–ethanol (also called AB or ABE or solvent)), by fermentation using current technologies from economically available agricultural residues (wheat, and barley straws, corn stover, sweet sorghum bagasse, switchgrass, etc.), and waste feedstocks such as food waste, municipal waste, and d...

BACKGROUND Butanol is a superior biofuel to ethanol because of its blend properties and higher energy density. However, its recovery by distillation from the fermentation broth is energy intensive. For this reason, butanol recovery by supercritical CO2 extraction from simulated and actual fermentation broths was studied. Recovery of butanol by this...

Butanol Biorefineries: Simultaneous Product Removal & Process Integration for Conversion of Biomass & Food Waste to Biofuel QURESHI1*, NASIB; HAIBO HUANG2, VIJAY SINGH3, SIQING LIU4, BADAL C SAHA1, STEPHEN R HUGHES4 1 United States Department of Agriculture (USDA), Agricultural Research Service (ARS), National Center for Agricultural Utilization R...

Butanol can be produced by fermentation from corn, molasses or lignocellulosic biomass for use as a chemical or superior biofuel [1]. However, butanol’s production is hampered by its toxicity to the microbial culture that produces it. In fermentation broths, final butanol concentrations typically range from 13-18 gL-1, which is low. Also its boilin...

In order for butanol fermentation to be a viable option, it is essential to recover it from fermentation broth using economical alternate in-situ product recovery techniques such as liquid/supercritical CO2 extraction [1] as compared to distillation [2]. This technique (liquid CO2 extraction & supercritical extraction) has advantages over others in...

Butanol production from sugars was once a commercial technology and it is once again being considered as a second generation liquid fuel after bioethanol. Sweet sorghum is a crop that when grown for sugar production generates a sugar syrup that is high in fructose, glucose, and sucrose, when compared to sugar beet syrup, which contains mainly sucro...

In order to produce butanol biofuel at a competitive price, agricultural residues such as SSB should be used. This feedstock was studied as a substitute to corn to lower feedstock costs and broaden beyond a food crop. In addition, cutting edge science & technology was applied. In these studies we used SSB at high solids concentration ranging from 8...

Itaconic acid (IA), an unsaturated 5-carbon dicarboxylic acid, is a building block platform chemical that is currently produced industrially from glucose by fermentation with Aspergillus terreus. However, lignocellulosic biomass has potential to serve as low cost source of sugars for production of IA. Research needs to be performed to find a suitab...

Inulins are polysaccharides that belong to an important class of carbohydrates known as fructans and are used by many plants as a means of storing energy. Inulins contain 20 to several thousand fructose units joined by β-2,1 glycosidic bonds, typically with a terminal glucose unit. Plants with high concentrations of inulin include: agave, asparagus...

Fermentative production of butanol for use as a biofuel or chemical feedstock is regarded as a promising renewable technology that reduces greenhouse gas emissions and has the potential to become a substitute for non-sustainable chemical production route. However, butanol toxicity to the producing microbes remains a barrier to achieving sufficientl...

A novel butanol fermentation process was developed in which sweet sorghum bagasse (SSB) was pretreated using liquid hot water (LHW) pretreatment technique followed by enzymatic hydrolysis and butanol (acetone butanol ethanol (ABE)) fermentation. A pretreatment temperature of 200 °C resulted in the generation of a hydrolyzate that inhibited butanol...

Biological pretreatment of lignocellulosic biomass by white-rot fungus can represent a low-cost and eco-friendly alternative to harsh physical, chemical or physico-chemical pretreatment methods to facilitate enzymatic hydrolysis. In this work, solid state cultivation of corn stover with Phlebia brevispora NRRL-13018 was optimized with respect to du...

A counter-current CO2 fractionation method was applied as a mean to recover n-butanol and other compounds that are typically obtained from biobutanol fermentation broth from aqueous solutions. The influence of operating variables, such as solvent-to-feed ratio, temperature, pressure and feed solution composition was experimentally studied in terms...

Economically important plants contain large amounts of inulin. Disposal of waste resulting from their processing presents environmental issues. Finding microorganisms capable of converting inulin waste to biofuel and valuable co-products at the processing site would have significant economic and environmental impact. We evaluated the ability of two...

The yajC gene (Lbuc_0921) from Lactobacillus buchneri NRRL B-30929 was identified from previous proteomics analyses in response to ethanol treatment. The YajC protein expression was increased by 15-fold in response to 10 % ethanol vs 0 % ethanol. The yajC gene encodes the smaller subunit of the preprotein translocase complex, which interacts with m...

This book is a unique guide to emerging stem cell technologies and the opportunities for their commercialisation. It provides in-depth analyses of the science, business, legal, and financing fundamentals of stem cell technologies, offering a holistic assessment of this emerging and dynamic segment of the field of regenerative medicine. Reviews the...

Energy security, environmental concerns, and business opportunities in the emerging bio-economy have generated strong interest in the production of n-butanol by fermentation. The acetone butanol ethanol (ABE or solvent) batch fermentation process is product limiting because butanol, even at low concentrations, inhibits the growth of fermenting micr...

Background Waste is currently a major problem in the world, both in the developing and the developed countries. Efficient utilization of food waste for fuel and chemical production can positively influence both the energy and environmental sustainability. This study investigated using food waste to produce acetone, butanol, and ethanol (ABE) by Clo...

Increased interest in sustainable production of renewable diesel and other valuable bioproducts is redoubling efforts to improve economic feasibility of microbial-based oil production. Yarrowia lipolytica is capable of employing a wide variety of substrates to produce oil and valuable co-products. We irradiated Y. lipolytica NRRL YB-567 with UV-C t...

These studies evaluated the economics of butanol production for a plant of annual capacity of 150 x 106 kg butanol year-1 by fermentation employing cellulosic substrates such as wheat straw and corn stover. The plant would also produce 78.1 x 106 kg of acetone and 28.5 x 106 kg of ethanol per year. It was determined that butanol production economic...

The cost of production of butanol (acetone-butanol-ethanol; or ABE) is determined by feedstock prices, fermentation, recovery, by-product credits and the waste water treatment. Along these lines, we have an intensive research program on the use of various agricultural substrates, fermentation strategies, product recovery, process integration, and p...

The cost of production of butanol (acetone-butanol-ethanol; or ABE) is determined by feedstock prices, fermentation, recovery, by-product credits and the waste water treatment. Along these lines, we have an intensive research program on the use of various agricultural substrates, fermentation strategies, product recovery, process integration, and p...

Papers presented in conferences

A yeast artificial chromosome (YAC) containing a multigene cassette for expression of enzymes that enhance xylose utilization (xylose isomerase [XI] and xylulokinase [XKS]) was constructed and transformed into Saccharomyces cerevisiae to demonstrate feasibility as a stable protein expression system in yeast and to design an assembly process suitabl...

Ethanol production from food wastes does not only solve environmental issues but also provides renewable biofuels. This study investigated the feasibility of producing ethanol from food wastes at high solids content (35%, w/w). A vacuum recovery system was developed and applied to remove ethanol from fermentation broth to reduce yeast ethanol inhib...

The production of ethanol from wheat straw (WS) by dilute acid pretreatment, bioabatement of fermentation inhibitors by a fungal strain, and simultaneous saccharification and fermentation (SSF) of the bio-abated WS to ethanol using an ethanologenic recombinant bacterium was studied at a pilot scale without sterilization. WS (124.2 g/L) was pretreat...

Transportation biofuel ethanol was produced from xylose and corn fiber hydrolyzate (CFH) in a batch reactor employing Escherichia coli FBR5. This strain was previously developed in our laboratory to use cellulosic sugars. The culture can produce up to 49.32 g L-1 ethanol from approximately 125 g L-1 xylose. Use of commercial nutrient sources such a...

Transportation biofuel ethanol was produced from xylose and corn fiber hydrolyzate (CFH) in a batch reactor employing Escherichia coli FBR5. This strain was previously developed in our laboratory to use cellulosic sugars. The culture can produce up to 49.32 g L-1 ethanol from approximately 125 g L-1 xylose. Use of commercial nutrient sources such a...

Isobutanol has particularly received strong attention due to its attributes as a potential fuel, such as relatively high energy content, diminished flammability and hygroscopicity, high octane value, and compatibility with gasoline. Whereas isobutanol is produced industrially via carbonylation (incorporation of carbon monoxide into organic compound...

Given the growing concerns about dwindling global oil deposits and greenhouse gas emissions, nations are working to produce renewable liquid biofuels with physical and chemical characteristics similar to those of gasoline. One such biofuel is butanol. Butanol is less corrosive than other biofuels and miscible with gasoline and diesel, and its energ...

In these studies, butanol (acetone butanol ethanol or ABE) was produced from concentrated lactose/whey permeate containing 211 g L(-1) lactose. Fermentation of such a highly concentrated lactose solution was possible due to simultaneous product removal using a pervaporation membrane. In this system, a productivity of 0.43 g L(-1) h(-1) was obtained...

Biorefineries outlines the processes and steps to successfully scale up production of two types of biofuels, butanol and ethanol, from cellulosic residues for commercial purposes. It covers practical topics, including biomass availability, pretreatment, fermentation, and water recycling, as well as policy and economic factors. This reflects the uni...

Currently, fermentation industries are structured around individual unit operations for the production of biofuels such as ethanol, butanol, and 2,3-butanediol. This structure is associated with increased capital and operational costs, and increased costs result in low profitability and increased prices for the consumer. The development of novel te...

This chapter describes process integration for butanol fermentation and simultaneous recovery. In unintegrated butanol fermentation, the concentration of the biofuel rarely exceeds 30 g/L due to its toxic nature. Such a low butanol concentration results in low reactor productivities of 0.30 g/L h, as well as low acetone-butanol-ethanol (ABE) yields...

This chapter discusses the importance of biomass in the development of renewable energy, the availability and allocation of biomass, its preparation for use in biorefineries, and the policies affecting biomass use. Bioenergy development depends on maximizing the amount of biomass obtained from agriculture and forestry, while prioritizing nature con...

This chapter considers the economics of producing butanol biofuel from lignocellulosic biomass and glycerol using integrated bioreactors that combine numerous unit operations. In order to compare these various processes, the authors performed evaluations using SuperPro Designer Software (version 9.0, built 8, special built 2012; Intelligen, Scotch...

Abstract In these studies concentrated sugar solutions of barley straw and corn stover hydrolysates were fermented using Clostridium beijerinckii P260 with simultaneous product recovery and compared with the performance of a control glucose batch fermentation process. The control glucose batch fermentation resulted in the production of 23.25 gL-1 A...

A simultaneous saccharification, fermentation, and recovery (SSFR) process was developed for the production of acetone-butanol-ethanol (AB or ABE), of which butanol is the main product, from corn stover employing Clostridium beijerinckii P260. Of the 86gL(-1) corn stover provided, over 97% of the sugars were released during hydrolysis and these wer...

Switchgrass (Panicum virgatum L.) is a perennial C4 grass that is being developed as a bioenergy crop because it has high production yields and suitable agronomic traits. Five switchgrass biomass samples from upland and lowland switchgrass ecotypes harvested at different stages or maturity were used in this study. Switchgrass samples contained 317....

As a result of increased gasoline prices, we focused on the production of butanol which contains more energy than ethanol on per gallon (or kg) basis from cellulosic agricultural biomass such as wheat straw using two different systems: i) separate hydrolysis, fermentation, and recovery (SHFR), and ii) simultaneous saccharification, fermentation and...

The yeast Kluyveromyces marxianus is a potential microbial catalyst for fuel ethanol production from a wide range of biomass substrates. To improve its growth and ethanol yield at elevated temperature under microaerophilic conditions, K. marxianus NRRL Y-1109 was irradiated with UV-C using automated protocols on a robotic platform for picking and s...

In these studies concentrated sugar solutions of barley straw and corn stover hydrolysates were fermented using Clostridium beijerinckii P260 with simultaneous product recovery and compared with the performance of a control glucose batch fermentation process. The control glucose batch fermentation resulted in the production of 23.25 gL−1 ABE from 5...

In these studies, concentrated xylose solution was fermented to ethanol using Escherichia coli FBR5 which can ferment both lignocellulosic sugars (hexoses and pentoses). E. coli FBR5 can produce 40-50 g L(-1) ethanol from 100 g L(-1) xylose in batch reactors. Increasing sugar concentration beyond this level results in the loss of sugar with the rea...