Optimal Growth Medium Research Articles

Combining culture optimization and synthetic biology to improve production and detection of secondary metabolites in Myxococcus xanthus: application to myxoprincomide.

Microbial secondary metabolites play crucial ecological roles in governing species interactions and contributing to their defense strategies. Their unique structures and potent bioactivities have been key in discovering antibiotics and anticancer drugs. Genome sequencing has undoubtedly revealed that myxobacteria constitute a huge reservoir of secondary metabolites as the well-known producers, actinomycetes. However, because most secondary metabolites are not produced in the laboratory context, the natural products from myxobacteria characterized to date represent only the tip of the iceberg. By combining the engineering of a dedicated Myxococcus xanthus DZ2 chassis strain with a two-step growth medium protocol, we provide a new approach called two-step Protocol for Resource Integration and Maximization-Biomolecules Overproduction and Optimal Screening Therapeutics (2PRIM-BOOST) for the production of non-ribosomal peptides synthetases (NRPS)/polyketides synthases (PKS) secondary metabolites from myxobacteria. We further show that the 2PRIM-BOOST strategy will facilitate the screening of secondary metabolites for biological activities of medical interest. As proof of concept, using a constitutive strong promoter, the myxoprincomide from M. xanthus DZ2 has been efficiently produced and its biosynthesis has been enhanced using the 2PRIM-BOOST approach, allowing the identification of new features of myxoprincomide. This strategy should allow the chances to produce and discover new NRPS, PKS, and mixed NRPS/PKS hybrid natural metabolites that are currently considered as cryptic and are the most represented in myxobacteria.IMPORTANCEMicrobial secondary metabolites are important in species interactions and are also a prolific source of drugs. Myxobacteria are ubiquitous soil-dwelling bacteria constituting a huge reservoir of secondary metabolites. However, because most of these molecules are not produced in the laboratory context, one can estimate that only one-tenth have been characterized to date. Here, we developed a new strategy called two-step Protocol for Resource Integration and Maximization-Biomolecules Overproduction and Optimal Screening Therapeutics (2PRIM-BOOST) that combines the engineering of a dedicated Myxococcus xanthus chassis strain together with growth medium optimization. By combining these strategies with the insertion of a constitutive promoter upstream the biosynthetic gene cluster (BGC), the production of myxoprincomide, a characterized low-produced secondary metabolite, was successfully and significantly increased. The 2PRIM-BOOST enriches the toolbox used to produce previously cryptic metabolites, unveil their ecological role, and provide new molecules of medical interest.

Selection and evaluation of optimal medium for Eisenia fetida in sustainable waste recycling

Present study explored the optimal medium for survival, growth, and reproductive performance of Eisenia fetida using kitchen waste, cow dung mixtures, and rice straw in a volume of 3834. Experimental setups involved various combinations of different experimental set such as set I:kitchen waste alone (3 kg); set II kitchen waste:dung (2 kg:1 kg); set III kitchen waste:dung (1 kg:2 kg) set IV Kitchen waste: Dung: Rice straw (1 kg:1 kg:1 kg) and set V:dung alone (3 kg) to evaluate earthworm survival rates. Eisenia fetida were introduced three days after setup initiation, with temperatures maintained between 20 °C–28 °C and moisture levels at 50–60%. Jute cloth covers prevented external intrusion and earthworm escape. The study monitored earthworm weight, cocoon production, hatchlings, and waste in a 90 day experiment, collecting adult earthworms, cocoons, and juveniles for observation. Results revealed that specific ratios of kitchen waste and cow dung significantly influenced earthworm survival, reproduction and vermicompost quality. The study highlights the significance of optimizing waste recycling processes using earthworms and emphasizes the need for suitable mediums to improve waste conversion efficiency and vermicompost quality.

Optimization of growth media and light requirement for obtaining maximum biomass and yield of mushroom (Cordyceps militaris)

Optimization of growth media and light requirement for obtaining maximum biomass and yield of mushroom (Cordyceps militaris)

Process optimized for production of iturin A in biofilm reactor by Bacillus velezensis ND.

In this research, to provide an optimal growth medium for the production of iturin A, the concentrations of key amino acid precursors were optimized in shake flask cultures using the response surface method. The optimized medium were applied in a biofilm reactor for batch fermentation, resulting in enhanced production of iturin A. On this basis, a step-wise pH control strategy and a combined step-wise pH and temperature control strategy were introduced to further improve the production of iturin A. Finally, the fed-batch fermentation was performed based on combined step-wise pH and temperature control. The titer and productivity of iturin A reached 7.86 ± 0.23g/L and 65.50 ± 1.92mg/L/h, respectively, which were 37.65 and 65.20% higher than that before process optimization.

Development of reliable in vitro long-term culture systems for hematopoietic cells of crayfish Cherax quadricarinatus and virus susceptibility assay

Long-term in vitro cultured crayfish cells can serve as a valuable tool for investigating various aspects of crayfish biology, encompassing cell physiology and viral mechanisms. Regrettably, they are difficult to maintain a highly active state and survive during long-term and continuous culture in vitro. In order to generate highly viable crayfish cell cultures, it is crucial to optimize dependable culture conditions and utilize a suitable cell medium. In this study, we have successfully developed reliable in vitro long-term culture systems for hematopoietic (HPT) cells of crayfish Cherax quadricarinatus by formulating an optimal crayfish cell growth medium (OCCM), including under two-dimensional (2D) and three-dimensional (3D) conditions. The novel medium was optimized by a mix of exogenous nutrients, crayfish plasma (CP) and shrimp serum-derived amino acids and saccharides within the Leibovitz's L-15 (L-15) medium. Our newly developed crayfish cell growth medium (CCM-28) enabled the culturing of HPT cells for over 142 days under 2D and over 60 days under 3D conditions, with consistent active cell proliferation observed over a 30-day incubation period. This proliferation was comparable to in vivo conditions, with a cell division rate exceeding 20%, suggesting that a high mitotic rate has been successfully achieved during long-term in vitro culture. Flow cytometry analysis further elucidated the mitosis-arrest of HPT cells cultured in vitro was predominantly observed in the G0/G1 phase. Furthermore, the cell subculture techniques have been established using mechanical dissociation method (in 2D) and substrate exchange method (in 3D). Additionally, the susceptibility of these cell cultures to covert mortality nodavirus (CMNV) and white spot syndrome virus (WSSV) was confirmed by capturing cytopathic effects (CPE) and analyzing viral copy numbers. Species identification using the cytochrome oxidase subunit I (COI) gene established the origin of the cell cultures from C. quadricarinatus. In conclusion, the successful development of highly viable crayfish cells in long-term in vitro culture systems, as demonstrated in this study, will significantly advance the research on immortalization in crayfish cells and the study of mechanisms related to viruses.

Therapeutic Potential of Bacteroides fragilis SNBF-1 as a Next-Generation Probiotic: In Vitro Efficacy in Lipid and Carbohydrate Metabolism and Antioxidant Activity.

This study explores the potential of aerotolerant Bacteroides fragilis (B. fragilis) strains as next-generation probiotics (NGPs), focusing on their adaptability in the gastrointestinal environment, safety profile, and probiotic functions. From 23 healthy infant fecal samples, we successfully isolated 56 beneficial B. fragilis strains. Notably, the SNBF-1 strain demonstrated superior cholesterol removal efficiency in HepG2 cells, outshining all other strains by achieving a remarkable reduction in cholesterol by 55.38 ± 2.26%. Comprehensive genotype and phenotype analyses were conducted, including sugar utilization and antibiotic sensitivity tests, leading to the development of an optimized growth medium for SNBF-1. SNBF-1 also demonstrated robust and consistent antioxidant activity, particularly in cell-free extracts, as evidenced by an average oxygen radical absorbance capacity value of 1.061 and a 2,2-diphenyl-1-picrylhydrazyl scavenging ability of 94.53 ± 7.31%. The regulation of carbohydrate metabolism by SNBF-1 was assessed in the insulin-resistant HepG2 cell line. In enzyme inhibition assays, SNBF-1 showed significant α-amylase and α-glucosidase inhibition, with rates of 87.04 ± 2.03% and 37.82 ± 1.36%, respectively. Furthermore, the cell-free supernatant (CFS) of SNBF-1 enhanced glucose consumption and glycogen synthesis in insulin-resistant HepG2 cells, indicating improved cellular energy metabolism. This was consistent with the observation that the CFS of SNBF-1 increased the proliferation of HepG2 cells by 123.77 ± 0.82% compared to that of the control. Overall, this research significantly enhances our understanding of NGPs and their potential therapeutic applications in modulating the gut microbiome.

Optimal fermentation conditions for growth and recombinant protein production in Pichia pastoris: Strain selection, ploidy level and carbon source

High-cell-density fermentation is a critical aspect of industrial protein production, requiring the selection of an optimal growth medium and carbon source. Pichia pastoris, a methylotrophic yeast, has been established as a widespread recombinant protein expression system in the food and pharmaceutical industries. The primary objective of this work was to create a superior platform for producing alternative proteins thus contributing to future innovation in these sectors. This study compared three wild-type strains, with two of them also analyzed in their diploid versions, using shake flasks and bioreactors. It investigated glucose and glycerol as carbon sources using mCherry as a protein model. Glycerol emerged as the preferred carbon source, resulting in over 40% increase in biomass concentrations compared to glucose across all strains. Notably, wild-type strain Y-7556 reached an exceptional biomass concentration of 244 g DCW/L in just 48 h, the highest reported to date, highlighting the potential of high-cell-density fermentation in P. pastoris. Regarding protein expression, the diploid version of Y-11430 produced >43% of purified mCherry protein after 123 h of fermentation, compared to the haploid counterpart. Our findings underscore the advantages of diploid strains, optimized fermentation media, and carbon source selection, effectively addressing crucial gaps in the literature.

Optimization of Growth Medium of Bacillus sp. TTMP20 by Response Surface Methodology

High-density culture is able to obtain high concentration and activity of microbes, which is a key technology for fermentation industry. This will greatly shorten fermentation cycle and reduce production cost. Bacillus sp. TTMP20 is a strain with a high yield of 2,3,5,6-tetramethylpyrazine (TTMP). In this study, the growth medium of Bacillus sp. TTMP20 was optimized. Different carbon/nitrogen sources were investigated, and the best carbon source (glucose) and nitrogen source (yeast extract) was determined. With the concentrations of glucose, yeast extract and pH as influence factors, response surface method was used to optimize the above-mentioned influence factors to maximize cell density of the strain. The optimal growth medium is as follows: 4 g/L of yeast extract, 15.754 g/L of glucose, 2 g/L of K2HPO4, 10 g/L of NaCl, and 6.50 of pH. The predicted and actual maxima are 1.388 and 1.3, respectively. This is 61.4% higher than the cell density of the basic medium. This will provide the adequate seed culture for the subsequent fermentation of TTMP, and improve the application level of Bacillus sp. TTMP20.

Optimization of a Bacterial Cultivation Medium via a Design-of-Experiment Approach in a Sartorius Ambr® 15 Fermentation Microbioreactor System

In the evolving landscape of sustainable biopharmaceutical process development, the utilization of bacteria in the production of various compounds via fermentation has attracted extensive attention from scientists. A successful fermentation process and the release of its associated products hinge on the synergy between an efficient bacterial strain and the formulation of a suitable growth medium. Balancing all nutrient levels of a growth medium to maximize microbial growth and the product quality is quite an intricate task. In this context, significant advancements have been achieved via the strategic implementation of design-of-experiment (DOE) methodologies and the utilization of parallel microbioreactor systems. This work presents a case study of the fermentation growth medium optimization of a Gram-negative bacterium of the Neisseriaceae family that releases outer membrane vesicles (OMVs), which represent a potential vaccine platform. To achieve this, the ability of Sartorius MODDE®13 DOE software to explore multiple variables and their interactions was combined with the functionality of a Sartorius Ambr® 15F parallel microbioreactor system. The findings reported in this study have led to the design of a well-suited fermentation medium for a Gram-negative bacterium and an improvement in the quality of the OMVs produced from it.

Production of perillic acid from orange essential oil by Yarrowia lipolytica using a top-aerated bioreactor.

R-(+)-Perillic acid, a promising anticancer and immunomodulatory agent, is the major product from the biotransformation of R-(+)-limonene-rich orange essential oil by the yeast Yarrowia lipolytica. Due to the abundance and low cost of orange essential oil, which is a byproduct of the citrus industry, we attempted to improve the biotransformation process by optimizing yeast cell mass production. Then, the whole process was transposed and adapted to a 2-L instrumented bioreactor. Cell mass production was optimized in shaker flasks using a statistical experimental design. The optimized medium (g·L-1: 22.9 glucose, 7.7 peptone, 4.1 yeast extract and 1.0 malt extract) resulted in a 13.0g·L-1 final cell concentration and 0.18g cell·L-1·h-1 productivity. A further increase to 18.0g·L-1 was achieved in a 2-L bioreactor upon fed-batch culture. High-purity limonene bioconversion was performed in the same bioreactor utilizing top aeration to diminish terpene volatilization; as a result, 839.6mg·L-1 perillic acid accumulated after 48h. Under the same conditions, industrial orange essential oil afforded 806.4mg·L-1 perillic acid. The yeast growthmedium optimization resulted in a twofold increase in biomass accumulation and a reduction in growth medium nitrogen sources, which lowered the catalytic biomass production cost. Compared with conventional bottom aeration, the bioreactor top aeration strategy resulted in higher bioconversion rates. The conditions developed for high-purity limonene bioconversion were successfully applied to low-cost orange essential oil, showing the robustness ofY. lipolyticayeast.

Characteristics of Epicoccum latusicollum as revealed by genomic and metabolic phenomic analysis, the causal agent of tobacco Epicoccus leaf spot.

Epicoccum latusicollum is a fungus that causes a severe foliar disease on flue-cured tobacco in southwest China, resulting in significant losses in tobacco yield and quality. To better understand the organism, researchers investigated its optimal growth conditions and metabolic versatility using a combination of traditional methods and the Biolog Phenotype MicroArray technique. The study found that E. latusicollum exhibited impressive metabolic versatility, being able to metabolize a majority of carbon, nitrogen, sulfur, and phosphorus sources tested, as well as adapt to different environmental conditions, including broad pH ranges and various osmolytes. The optimal medium for mycelial growth was alkyl ester agar medium, while oatmeal agar medium was optimal for sporulation, and the optimum temperature for mycelial growth was 25°C. The lethal temperature was 40°C. The study also identified arbutin and amygdalin as optimal carbon sources and Ala-Asp and Ala-Glu as optimal nitrogen sources for E. latusicollum. Furthermore, the genome of E. latusicollum strain T41 was sequenced using Illumina HiSeq and Pacific Biosciences technologies, with 10,821 genes predicted using Nonredundant, Gene Ontology, Clusters of Orthologous Groups, Kyoto Encyclopedia of Genes and Genomes, and SWISS-PROT databases. Analysis of the metabolic functions of phyllosphere microorganisms on diseased tobacco leaves affected by E. latusicollum using the Biolog Eco microplate revealed an inability to efficiently metabolize a total of 29 carbon sources, with only tween 40 showing some metabolizing ability. The study provides new insights into the structure and function of phyllosphere microbiota and highlights important challenges for future research, as well as a theoretical basis for the integrated control and breeding for disease resistance of tobacco Epicoccus leaf spot. This information can be useful in developing new strategies for disease control and management, as well as enhancing crop productivity and quality.

Specific features of <i>in vitro</i> micropropagation of various representatives of the genus <i>Rhododendron</i>

One of the best plants for landscaping urban areas are representatives of the genus Rhododendron L. However, there is the problem of obtaining planting material because traditional propagation methods are inefficient or take a lot of time and resources. In vitro micropropagation can be a solution to this problem. The research objects were Rhododendron Helsinky University, Rhododendron hybrid Marianna v. Weizsacker, and Rhododendron caucasicum var. Rosea. Three variants of Woody Plant Medium (WPM) were used for the experiment: with the addition of benzylaminopurine/indolylbutyric acid or naphthylacetic acid/kinetin in the proportion of mg/l, and a control variant without hormones. The analysis of the effect of different concentrations of phytohormones has demonstrated that for different representatives there are specific combinations of growth regulators. For Rh. caucasicum var. Rosea the hormone-free medium was the most suitable for plant growth as well as the appearance of shoots of order II. For Rh. hybrid Marianna v. Weizsacker, the optimal medium for plant growth was also a hormone-free medium, but the addition of naphthylacetic acid / kinetin enhanced the tillering. The presence of benzylaminopurine / indolylbutyric in the medium had a negative effect on the species and the hybrid. The use of these hormones for Rh. Helsinky University resulted in stimulation of growth and tillering of the plant, while naphthylacetic acid / kinetin hormones caused a depressing effect.

Optimization of growth medium for microbially induced calcium carbonate precipitation (MICP) treatment of desert sand

Optimization of growth medium for microbially induced calcium carbonate precipitation (MICP) treatment of desert sand

Optimal culture medium selection and supplementation for recombinant thaumatin II production by Komagataella phaffii

Sweet protein thaumatin, a promising alternative to table sugar, can overcome several drawbacks imposed by other sugar alternatives in the market today. Recombinant technology involving Komagataella phaffii (previously known as Pichia pastoris) has the potential to facilitate a uniform and large-scale production of this protein. To ensure maximal yield from the bioprocess, this study performed a screening to identify the media composition that exhibits the highest secretion yield of recombinant thaumatin II and favourable growth of the host organism. To achieve this, the most recommended media formulations for K. phaffii namely, BSM, FM22, MGY, BMGY, MBSM and d’Anjou media were investigated. It was identified from this study that the highest yields of recombinant thaumatin II were achieved from BMGY, FM22 and BSM media, irrespective of not exhibiting the highest cell growth. Despite exhibiting a lower cell density than FM22, the BMGY medium resulted in 62.79 mg/L of recombinant thaumatin II, which is 1–2 times higher than the former. This observation facilitated an understanding that the optimal medium for cell growth is not necessarily optimal for recombinant protein production. Moreover, a comparison between baffled and non-baffled flasks demonstrated that the former leads to a higher secretion yield, thereby indicating the importance of sufficient oxygen transfer into the medium. Furthermore, casamino acids and vitamins were supplemented to the media, where the latter contributed to an increased yield of thaumatin. As such, the highest protein yield of 68.60 mg/L was achieved for BMGY supplemented with vitamins.

Unleashing the potential of Phlox (Phlox drummondii): Evaluating the influence of growth regulators and growing media

During the early spring in the woodlands of eastern North America, Phlox drummondii emerges as a perennial plant adorned with a profusion of blooms in shades of blue, purple, pink, or white. Its evergreen nature adds to its charm. To manage the growth of plants or specific plant parts, plant growth regulators (PGRs) are synthesized and employed, serving as valuable tools for controlling and directing the development of various plant species. A diverse range of ornamental plants, such as Phlox drummondii, have been documented to receive exogenous applications of plant growth regulators (PGRs). Among these regulators, gibberellins (GA) play a vital role by delaying senescence in flowers and promoting the breaking of dormancy in seeds, bulbs, and corms of ornamental plants. The experiment aimed to assess the performance and determine the optimal growth medium for Phlox. Five distinct growth media were employed as treatments during the study, which took place in the Horticulture Department of Gomal University. Collected data underwent analysis through ANOVA and Tuckey HSD tests. The study’s findings revealed that the highest plant height (16 cm) was observed in the control treatment with PGR 1, closely followed by PGR 2 (11.5 cm). The treatment labeled as T5, composed of a mixture of 1/3 sand, 1/3 poultry manure, and 1/3 soil, demonstrated the most favorable results across multiple parameters such as bud initiation (BI), first flower emergence (FFE), flowers per plant (FPP), branches per plant (BPP), leaves per plant (LPP), number of roots (NR), field life of flowers (FLF), and flower diameter (FD). T4, T3, T2, and T1 treatments also exhibited similar positive outcomes, aligning with the promising performance of T5.

Targeting the IGF-Axis in Cultured Pediatric High-Grade Glioma Cells Inhibits Cell Cycle Progression and Survival.

Pediatric high-grade gliomas (pHGG) accounts for approximately 8-12% of primary brain tumors in children. Prognosis is poor, with a median survival of 9-15 months. Insulin-like growth factor 1-receptor (IGF-1R) gene amplifications have been identified in high-grade gliomas and may contribute to its highly aggressive phenotype, but the effect of IGF inhibitors on pHGG is yet to be determined. In the present study, we analyzed the response of patient-derived pediatric high-grade glioma cells to a novel IGF-1R inhibitor, the IGF-Trap. Using immunohistochemistry, we found that IGF-1R was localized to both the nucleus and cell membrane in different pHGG patient-derived xenograft (PDX) lines under basal conditions. In response to ligand binding, nuclear levels of the receptor increased, and this was associated with the transcriptional upregulation of both the receptor and cyclin D1, suggesting that IGF-1R could regulate its own expression and cell cycle progression in these cells. Insulin-like growth factor-1 (IGF-1) increased the proliferation of the pHGG cells DIPG13 and SGJ2, and this could be blocked by the addition of the IGF-Trap. The IGF-Trap reduced the colony formation of these cells in an optimal growth medium and impeded the ability of IGF-1 to rescue DIPG13 cells from starvation-induced apoptosis. Collectively, these results implicate the IGF-1 axis in the regulation of cell cycle progression, cellular proliferation, and cell survival in pHGG, and identify the IGF-axis as a target and the IGF-Trap as a potential inhibitor of this axis in pHGG.

High Efficiency Regeneration System from Blueberry Leaves and Stems.

The main propagation approach is tissue culture in blueberries, and tissue culture is an effective and low-cost method with higher economic efficiency in blueberries. However, there is a lack of stable and efficient production systems of industrialization of tissue culture in blueberries. In this study, the high-efficiency tissue culture and rapid propagation technology system were established based on blueberry leaves and stems. The optimal medium for callus induction was WPM (woody plant medium) containing 2.0 mg/L Forchlorfenuron (CPPU), 0.2 mg/L 2-isopentenyladenine (2-ip) with a 97% callus induction rate and a callus differentiation rate of 71% by using blueberry leaves as explants. The optimal secondary culture of the leaf callus medium was WPM containing 3.0 mg/L CPPU with an increment coefficient of 24%. The optimal bud growth medium was WPM containing 1.0 mg/L CPPU, 0.4 mg/L 2-ip, with which the growth of the bud was better, stronger and faster. The optimal rooting medium was 1/2 Murashige and Skoog (1/2MS) medium containing 2.0 mg/L naphthylacetic acid (NAA), with which the rooting rate was 90% with shorter rooting time and more adventitious root. In addition, we established a regeneration system based on blueberry stems. The optimal preculture medium in blueberry stem explants was MS medium containing 2-(N-morpholino) ethanesulfonic acid (MES) containing 0.2 mg/L indole-3-acetic acid (IAA), 0.1 mg/L CPPU, 100 mg/L NaCl, with which the germination rate of the bud was 93%. The optimal medium for fast plant growth was MS medium containing MES containing 0.4 mg/L zeatin (ZT), 1 mg/L putrescine, 1 mg/L spermidine, 1 mg/L spermidine, which had a good growth state and growth rate. The optimal cultivation for plantlet growth was MS medium containing MES containing 0.5 mg/L isopentene adenine, with which the plantlet was strong. The optimal rooting medium for the stem was 1/2MS medium containing 2.0 mg/L NAA, with which the rooting rate was 93% with a short time and more adventitious root. In conclusion, we found that stem explants had higher regeneration efficiency for a stable and efficient production system of industrialization of tissue culture. This study provides theoretical guidance and technical support in precision breeding and standardization and industrialization in the blueberry industry.

Cultural and morphological features of <i>Fusarium oxysporum</i> and <i>Fusarium brachygibbosum</i> species associated with garden strawberry plants

This study is focused on two micromycetes of the genus Fusarium: the complex species F. oxysporum and F. brachygibbosum Padwick isolated from strawberry roots from different regions of Russia. Studies were performed in 2021-2022 on samples of symptomatic plants collected in the Republic of Crimea and Voronezh Oblast. The micromycetes were studied by means of a combination of classical biological methods and molecular genetic approaches with decoding of nucleotide sequences. The subject of the work was to study the biological features of F. oxysporum and F. brachygibbosum Padwick. The work included the study of macro- and micro features of the target objects. The following cultural features were determined: structure and coloring of aerial and substrate mycelium, character of colony surface, growth rate, sporulation of fungi, pigmentation of structures and nutrient media on the studied media. The species F. brachygibbosum from planting material of strawberry originating from the Republic of Crimea was isolated and identified for the first time. As a result of studies of different composition of nutrient media, it was found that potato-glucose agar (PGA) 2 % is the most optimal nutrient medium for growth and sporulation of target isolates. It was determined that the addition of citric acid to PGA altered the macro features of the mycelium of F. brachygibbosum. Universal sites of several genes (internal transcribed spacer, actin gene, elongation translation factor gene) were studied for species identification of F. oxysporum and F. brachygibbosum. Variable gene sites for identification of the species identity of Fusarium isolates were determined. It was revealed that ITS1-5.8S-ITS2 and TEF sites could be used for interspecific differentiation of Fusarium wilts.

Innovative Strategies to Overcome Antimicrobial Resistance and Tolerance.

Antimicrobial resistance and tolerance are natural phenomena that arose due to evolutionary adaptation of microorganisms against various xenobiotic agents. These adaptation mechanisms make the current treatment options challenging as it is increasingly difficult to treat a broad range of infections, associated biofilm formation, intracellular and host adapted microbes, as well as persister cells and microbes in protected niches. Therefore, novel strategies are needed to identify the most promising drug targets to overcome the existing hurdles in the treatment of infectious diseases. Furthermore, discovery of novel drug candidates is also much needed, as few novel antimicrobial drugs have been introduced in the last two decades. In this review, we focus on the strategies that may help in the development of innovative small molecules which can interfere with microbial resistance mechanisms. We also highlight the recent advances in optimization of growth media which mimic host conditions and genome scale molecular analyses of microbial response against antimicrobial agents. Furthermore, we discuss the identification of antibiofilm molecules and their mechanisms of action in the light of the distinct physiology and metabolism of biofilm cells. This review thus provides the most recent advances in host mimicking growth media for effective drug discovery and development of antimicrobial and antibiofilm agents.

Potential of Single Cell Protein Production Using Waste as Growth Medium

Feed is an important factor affecting the growth of cultured fish. Around 86.5% of the production cost of aquaculture is allocated for the purchase of feed. Good quality and efficient feed is a determinant of the success of aquaculture business. Single Cell Protein (SCP) is a dry cell product of single cell microorganisms. SCP production is generally not only protein but also free amino acids, lipids, carbohydrates, vitamins and minerals. The purpose of this study was to analyze the growth media of Bacillus Cereus which will be used as a source of SCP by using some easy-to-use waste. The research method used is an experimental method using 2 isolates of Bacillus cereus bacteria, namely B. cereus strain SN7 and a consortium of bacterial isolates. Both isolates were grown in tofu liquid waste media, sago liquid waste media, and molasses waste media as a carbon source added with egg white as a nitrogen source with 3 replications in each treatment. The results showed that the most optimal growth medium for B. cereus strain SN7 and the consortium was molasses waste modified media which was incubated for 24 hours, compared to modified media for sago waste and tofu waste. For comparison, the isolates of B. cereus and consortium still had a higher growth potential than the isolates of strain SN7 which had been incubated for 24 hours.