Biotechnology of Rhodococcus for the production of valuable compounds

Abstract Bacteria belonging to Rhodococcus genus represent ideal candidates for microbial biotechnology applications because of their metabolic versatility, ability to degrade a wide range of organic compounds, and resistance to various stress conditions, such as metal toxicity, desiccation, and high concentration of organic solvents. Rhodococcus spp. strains have also peculiar biosynthetic activities that contribute to their strong persistence in harsh and contaminated environments and provide them a competitive advantage over other microorganisms. This review is focused on the metabolic features of Rhodococcus genus and their potential use in biotechnology strategies for the production of compounds with environmental, industrial, and medical relevance such as biosurfactants, bioflocculants, carotenoids, triacylglycerols, polyhydroxyalkanoate, siderophores, antimicrobials, and metal-based nanostructures. These biosynthetic capacities can also be exploited to obtain high value-added products from low-cost substrates (industrial wastes and contaminants), offering the possibility to efficiently recover valuable resources and providing possible waste disposal solutions. Rhodococcus spp. strains have also recently been pointed out as a source of novel bioactive molecules highlighting the need to extend the knowledge on biosynthetic capacities of members of this genus and their potential utilization in the framework of bioeconomy. Key points • Rhodococcus possesses promising biosynthetic and bioconversion capacities. • Rhodococcus bioconversion capacities can provide waste disposal solutions. • Rhodococcus bioproducts have environmental, industrial, and medical relevance.

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Photocatalytic three-component asymmetric sulfonylation via direct C(sp3)-H functionalization

Nature Communications ◽

10.1038/s41467-021-22690-3 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Shi Cao ◽

Wei Hong ◽

Ziqi Ye ◽

Lei Gong

Keyword(s):

Asymmetric Catalysis ◽

Organic Synthesis ◽

Photochemical Reaction ◽

Low Cost ◽

Bioactive Molecules ◽

Atom Economy ◽

Mild Conditions ◽

Wide Range ◽

Unsaturated Carbonyl Compound ◽

Direct Functionalization

AbstractThe direct and selective C(sp3)-H functionalization of cycloalkanes and alkanes is a highly useful process in organic synthesis owing to the low-cost starting materials, the high step and atom economy. Its application to asymmetric catalysis, however, has been scarcely explored. Herein, we disclose our effort toward this goal by incorporation of dual asymmetric photocatalysis by a chiral nickel catalyst and a commercially available organophotocatalyst with a radical relay strategy through sulfur dioxide insertion. Such design leads to the development of three-component asymmetric sulfonylation involving direct functionalization of cycloalkanes, alkanes, toluene derivatives or ethers. The photochemical reaction of a C(sp3)-H precursor, a SO2 surrogate and a common α,β-unsaturated carbonyl compound proceeds smoothly under mild conditions, delivering a wide range of biologically interesting α-C chiral sulfones with high regio- and enantioselectivity (>50 examples, up to >50:1 rr and 95% ee). This method is applicable to late-stage functionalization of bioactive molecules, and provides an appealing access to enantioenriched compounds starting from the abundant hydrocarbon compounds.

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Utilization of Food Processing By-products in Extrusion Processing: A Review

Frontiers in Sustainable Food Systems ◽

10.3389/fsufs.2020.603751 ◽

2021 ◽

Vol 4 ◽

Author(s):

Debomitra Dey ◽

Jana K. Richter ◽

Pichmony Ek ◽

Bon-Jae Gu ◽

Girish M. Ganjyal

Keyword(s):

Functional Properties ◽

Low Cost ◽

Value Added ◽

Raw Material ◽

Practical Applications ◽

Extrusion Processing ◽

High Production Rate ◽

Wide Range ◽

Extruded Products ◽

By Products

The processing of agricultural products into value-added food products yields numerous by-products or waste streams such as pomace (fruit and vegetable processing), hull/bran (grain milling), meal/cake (oil extraction), bagasse (sugar processing), brewer's spent grain (brewing), cottonseed meal (cotton processing), among others. In the past, significant work in exploring the possibility of the utilization of these by-products has been performed. Most by-products are highly nutritious and can be excellent low-cost sources of dietary fiber, proteins, and bioactive compounds such as polyphenols, antioxidants, and vitamins. The amount of energy utilized for the disposal of these materials is far less than the energy required for the purification of these materials for valorization. Thus, in many cases, these materials go to waste or landfill. Studies have been conducted to incorporate the by-products into different foods in order to promote their utilization and tackle their environmental impacts. Extrusion processing can be an excellent avenue for the utilization of these by-products in foods. Extrusion is a widely used thermo-mechanical process due to its versatility, flexibility, high production rate, low cost, and energy efficiency. Extruded products such as direct-expanded products, breakfast cereals, and pasta have been developed by researchers using agricultural by-products. The different by-products have a wide range of characteristics in terms of chemical composition and functional properties, affecting the final products in extrusion processing. For the practical applications of these by-products in extrusion, it is crucial to understand their impacts on the qualities of raw material blends and extruded products. This review summarizes the general differences in the properties of food by-products from different sources (proximate compositions, physicochemical properties, and functional properties) and how these properties and the extrusion processing conditions influence the product characteristics. The discussion of the by-product properties and their impacts on the extrudates and their nutritional profile can be useful for food manufacturers and researchers to expand their applications. The gaps in the literature have been highlighted for further research and better utilization of by-products with extrusion processing.

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High Value Thin Wafer Support Technology for 3DIC

International Symposium on Microelectronics ◽

10.4071/isom-wp43 ◽

2014 ◽

Vol 2014 (1) ◽

pp. 000718-000723

Author(s):

Jared Pettit ◽

Alman Law ◽

Alex Brewer ◽

John Moore

Keyword(s):

Adhesion Force ◽

Low Cost ◽

New Technology ◽

Value Added ◽

Batch Process ◽

New Approach ◽

Wide Range ◽

Temporary Bonding ◽

Technical Challenges ◽

Conventional Practice

As the 3DIC market matures, more is understood about the technical and cost challenges [1]. At the 2013 Semicon-West gathering, a panel of global experts identified these technical challenges to represent some of the most significant barriers to the industry's efforts to maintain progress with Moore's Law [2]. Searching and achieving high value manufacturing of 3DIC devices requires wrestling with several technologies and processes, all which may assert a different value for the manufacturer [3]. Current technologies for thin wafer support use a wide range of adhesives applied to the device wafer, bonded to a carrier, backside processed, and de-bonded by an array of methods. Daetec has been investigating temporary bonding for nearly 15yrs, is producing a range of products for semiconductor (e.g. WaferBondTM (Brewer-Science, Inc.)) [4], and for the display market using a low-cost tunable adhesion-force material that is peeled by simple means [5]. Daetec has developed a new technology, DaeBond 3DTM, allowing de-bonding to occur in a batch process while thinned wafers are affixed to film frames. This new approach provides a shift in conventional practice. Our paper presents several temporary bonding options with DaeBond 3DTM in an effort to define value-added approaches for thin wafer handling.

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Green Preparation of Fluorescent Carbon Quantum Dots from Cyanobacteria for Biological Imaging

Polymers ◽

10.3390/polym11040616 ◽

2019 ◽

Vol 11 (4) ◽

pp. 616 ◽

Cited By ~ 12

Author(s):

Xi Wang ◽

Pei Yang ◽

Qian Feng ◽

Taotao Meng ◽

Jing Wei ◽

...

Keyword(s):

Quantum Dots ◽

Carbon Source ◽

Large Scale ◽

Low Cost ◽

Average Diameter ◽

Carbon Quantum Dots ◽

Water Soluble ◽

High Concentration ◽

Wide Range ◽

Low Cytotoxicity

Biomass-based carbon quantum dots (CQDs) have become a significant carbon materials by their virtues of being cost-effective, easy to fabricate and low in environmental impact. However, there are few reports regarding using cyanobacteria as a carbon source for the synthesis of fluorescent CQDs. In this study, the low-cost biomass of cyanobacteria was used as the sole carbon source to synthesize water-soluble CQDs by a simple hydrothermal method. The synthesized CQDs were mono-dispersed with an average diameter of 2.48 nm and exhibited excitation-dependent emission performance with a quantum yield of 9.24%. Furthermore, the cyanobacteria-derived CQDs had almost no photobleaching under long-time UV irradiation, and exhibited high photostability in the solutions with a wide range of pH and salinity. Since no chemical reagent was involved in the synthesis of CQDs, the as-prepared CQDs were confirmed to have low cytotoxicity for PC12 cells even at a high concentration. Additionally, the CQDs could be efficiently taken up by cells to illuminate the whole cell and create a clear distinction between cytoplasm and nucleus. The combined advantages of green synthesis, cost-effectiveness and low cytotoxicity make synthesized CQDs a significant carbon source and broaden the application of cyanobacteria and provide an economical route to fabricate CQDs on a large scale.

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Production of Bacterial Cellulose by Acetobacter tropicalis Isolated from Decaying Apple Waste

Asian Journal of Chemistry ◽

10.14233/ajchem.2022.23598 ◽

2022 ◽

Vol 34 (2) ◽

pp. 453-458

Author(s):

Lakhvinder Kaur ◽

Shachi Shah

Keyword(s):

Bacterial Cellulose ◽

Organic Waste ◽

Fruits And Vegetables ◽

Low Cost ◽

Value Added ◽

Bacterial Isolates ◽

Research Areas ◽

Wide Range ◽

Potential Alternative ◽

Value Added Products

Fruits and vegetables have the highest wastage rates of 45% of any food. One of the recent research areas is food waste valorization as a potential alternative to the disposal of a wide range of organic waste using microorganisms as one of the strategies known as microbial valorization. Bacterial cellulose is best known microbial valorization product because of its low cost, environmentally friendly nature, renewability, nanoscale dimensions, biocompatibility and extremely high hydrophilicity. Therefore, present study focuses on the isolation, characterization and identification of cellulose producing bacteria from decaying apple waste. Cellulose producers were isolated from decaying apple waste. The bacterial isolates obtained were identified through the morphological biochemical, physiological and molecular identification. The bacterial isolates exhibited potential remediation options to biovalorize decaying fruit waste by producing value added products as well as in safe disposal of waste.

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The Application of Supercritical Fluids Technology to Recover Healthy Valuable Compounds from Marine and Agricultural Food Processing By-Products: A Review

Processes ◽

10.3390/pr9020357 ◽

2021 ◽

Vol 9 (2) ◽

pp. 357

Author(s):

Jianjun Zhou ◽

Beatriz Gullón ◽

Min Wang ◽

Patricia Gullón ◽

José M. Lorenzo ◽

...

Keyword(s):

Value Added ◽

Green Technology ◽

Sustainable Growth ◽

Bioactive Molecules ◽

Food Sector ◽

Working Principle ◽

Valuable Compounds ◽

By Products ◽

Active Substances ◽

Agricultural Food

Food by-products contain a remarkable source of bioactive molecules with many benefits for humans; therefore, their exploitation can be an excellent opportunity for the food sector. Moreover, the revalorization of these by-products to produce value-added compounds is considered pivotal for sustainable growth based on a circular economy. Traditional extraction technologies have several drawbacks mainly related to the consumption of hazardous organic solvents, and the high temperatures maintained for long extraction periods which cause the degradation of thermolabile compounds as well as a low extraction efficiency of desired compounds. In this context, supercritical fluid extraction (SFE) has been explored as a suitable green technology for the recovery of a broad range of bioactive compounds from different types of agri-food wastes. This review describes the working principle and development of SFE technology to valorize by-products from different origin (marine, fruit, vegetable, nuts, and other plants). In addition, the potential effects of the extracted active substances on human health were also approached.

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Systems biology and metabolic engineering of Rhodococcus for bioconversion and biosynthesis processes

Folia Microbiologica ◽

10.1007/s12223-021-00892-y ◽

2021 ◽

Author(s):

Eva Donini ◽

Andrea Firrincieli ◽

Martina Cappelletti

Keyword(s):

Renewable Resources ◽

Rational Design ◽

Low Cost ◽

Value Added ◽

Adaptive Laboratory Evolution ◽

Toxic Compounds ◽

Laboratory Evolution ◽

Metabolic Versatility ◽

Genomic Basis ◽

Value Added Products

AbstractRhodococcus spp. strains are widespread in diverse natural and anthropized environments thanks to their high metabolic versatility, biodegradation activities, and unique adaptation capacities to several stress conditions such as the presence of toxic compounds and environmental fluctuations. Additionally, the capability of Rhodococcus spp. strains to produce high value-added products has received considerable attention, mostly in relation to lipid accumulation. In relation with this, several works carried out omic studies and genome comparative analyses to investigate the genetic and genomic basis of these anabolic capacities, frequently in association with the bioconversion of renewable resources and low-cost substrates into triacylglycerols. This review is focused on these omic analyses and the genetic and metabolic approaches used to improve the biosynthetic and bioconversion performance of Rhodococcus. In particular, this review summarizes the works that applied heterologous expression of specific genes and adaptive laboratory evolution approaches to manipulate anabolic performance. Furthermore, recent molecular toolkits for targeted genome editing as well as genome-based metabolic models are described here as novel and promising strategies for genome-scaled rational design of Rhodococcus cells for efficient biosynthetic processes application.

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Simultaneous Bioconversion of Gelatinized Starchy Waste from the Rice Noodle Manufacturing Process to Lactic Acid and Maltose-Forming α-Amylase by Lactobacillus plantarum S21, Using a Low-Cost Medium

Fermentation ◽

10.3390/fermentation5020032 ◽

2019 ◽

Vol 5 (2) ◽

pp. 32 ◽

Cited By ~ 4

Author(s):

Kridsada Unban ◽

Apinun Kanpiengjai ◽

Nuttapong Khatthongngam ◽

Chalermpong Saenjum ◽

Chartchai Khanongnuch

Keyword(s):

Lactic Acid ◽

Lactobacillus Plantarum ◽

Low Cost ◽

Corn Steep Liquor ◽

Lactic Acid Production ◽

Value Added ◽

Tween 80 ◽

Industrial Wastes ◽

Acid Yield ◽

Medium Components

A direct bioconversion of gelatinized starchy waste (GSW) to lactic acid by amylolytic lactic acid bacterium Lactobacillus plantarum S21 was investigated. Corn steep liquor (CSL) was selected as the most suitable low-cost nitrogen source for replacing yeast extract, beef extract, and peptone in De Man, Rogosa and Sharpe (MRS) medium. Plackett–Burman design results indicated that GSW and CSL were the two most nutrients that significantly influence lactic acid production, among eight medium components, including GSW, CSL, K2HPO4, CH3COONa, (NH4)2HC6H5O7, MgSO4, MnSO4, and Tween 80. A new low-cost medium containing only GSW (134.4 g/L) and CSL (187.7 g/L) was achieved as omitting other six components from the optimized medium had no effect on lactic acid yield. Batch fermentation at 37 °C both in 1 L and 10 L jar fermenters showed non-significantly different productivity. A by-product, maltose-forming α-amylase, was successfully achieved up to 96% recovery yield using an ultrafiltration unit equipped with a 50 kDa cut-off membrane. Crude lactic acid exhibited the additional benefit of antimicrobial activity against food and feed pathogens Salmonella enterica serovar Typhimurium TISTR 292, Vibrio cholerae TH-001, and also E. coli ATCC 25922. This study presents a promising bioprocess for the simultaneous production of lactic acid, and a value-added food enzyme, using only two industrial wastes, GSW and CSL, as the medium components.

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The Role of Heterotrophic Microalgae in Waste Conversion to Biofuels and Bioproducts

Processes ◽

10.3390/pr9071090 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1090

Author(s):

Teresa Lopes da Silva ◽

Patrícia Moniz ◽

Carla Silva ◽

Alberto Reis

Keyword(s):

Unsaturated Fatty Acids ◽

Waste Treatment ◽

Culture Media ◽

Low Cost ◽

Algal Growth ◽

Value Added ◽

Production Costs ◽

Microalgal Biomass ◽

Heterotrophic Microalgae ◽

Wide Range

In the last few decades, microalgae have attracted attention from the scientific community worldwide, being considered a promising feedstock for renewable energy production, as well as for a wide range of high value-added products such as pigments and poly-unsaturated fatty acids for pharmaceutical, nutraceutical, food, and cosmetic markets. Despite the investments in microalgae biotechnology to date, the major obstacle to its wide commercialization is the high cost of microalgal biomass production and expensive product extraction steps. One way to reduce the microalgae production costs is the use of low-cost feedstock for microalgae production. Some wastes contain organic and inorganic components that may serve as nutrients for algal growth, decreasing the culture media cost and, thus, the overall process costs. Most of the research studies on microalgae waste treatment use autotrophic and mixotrophic microalgae growth. Research on heterotrophic microalgae to treat wastes is still scarce, although this cultivation mode shows several benefits over the others, such as higher organic carbon load tolerance, intracellular products production, and stability in production all year round, regardless of the location and climate. In this review article, the use of heterotrophic microalgae to simultaneously treat wastes and produce high value-added bioproducts and biofuels will be discussed, critically analyzing the most recent research done in this area so far and envisioning the use of this approach to a commercial scale in the near future.

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Adsorption of Cadmium from Aqueous Solutions Using Low cost Materials-A Review

International Journal of Engineering & Technology ◽

10.14419/ijet.v7i4.2.19995 ◽

2018 ◽

Vol 7 (4.2) ◽

pp. 26 ◽

Cited By ~ 1

Author(s):

M. Padmaja ◽

R. Bhavani ◽

R. Pamila

Keyword(s):

Low Cost ◽

Industrial Wastes ◽

Anthropogenic Sources ◽

Human Consumption ◽

Nano Materials ◽

Industrial Emissions ◽

Low Concentrations ◽

Wide Range ◽

Water And Wastewater ◽

Multiple Heavy Metals

With the onset of industrialization, a lot of anthropogenic sources of cadmium, including industrial emissions, application of fertilizers and sewage sludge to farm land has lead to the contamination of water bodies, and has increased cadmium uptake by agricultural crops, grown for human consumption. Cadmium when present, even at low concentrations may pose serious health as well as environmental hazards. The use of various materials has been widely investigated as a replacement of recent expensive methods for removing cadmium from water and wastewater. Plant based natural materials, agricultural products, nano materials and industrial wastes are efficiently used as low-cost adsorbents. Until now, most of the researchers have attempted to review the literature for multiple heavy metals. In the current review, an elaborate list of literature has been compiled to provide information on a wide range of natural as well as modified adsorbent materials for the removal of Cadmium from wastewater.

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