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Objectives: Bacillus subtilis is a plant growth promoting bacterium (PGPB) that acts as a microbial fertilizer and biocontrol agent, providing benefits such as boosting crop productivity and improving nutrient content. It is able to produce secondary metabolites and endospores simultaneously, enhancing its ability to survive in unfavorable conditions and eliminate competing microorganisms. Optimizing cultivation methods to produce B. subtilis MSCL 897 spores on an industrial scale, requires a suitable medium, typically made from food industry by-products, and optimal temperature and pH levels to achieve high vegetative cell and spore densities with maximum productivity. Results: This research demonstrates successful pilot-scale (100 L bioreactor) production of a biocontrol agent B. subtilis with good spore yields (1.5 × 109 spores mL−1) and a high degree of sporulation (>80%) using a low-cost cultivation medium. Culture samples showed excellent antifungal activity (1.6–2.3 cm) against several phytopathogenic fungi. An improved methodology for inoculum preparation was investigated to ensure an optimal seed culture state prior to inoculation, promoting process batch-to-batch repeatability. Increasing the molasses concentration in the medium and operating the process in fed-batch mode with additional molasses feed, did not improve the overall spore yield, hence, process operation in batch mode with 10 g molasses L−1 is preferred. Results also showed that the product quality was not significantly impacted for up to 12 months of storage at room temperature. Conclusion: An economically-feasible process for B. subtilis-based biocontrol agent production was successfully developed at the pilot scale. [ABSTRACT FROM AUTHOR]

Kojic acid is a valuable compound that contributes to various therapeutic and cosmetic applications. Organic nitrogen partially contributes to fermentation and mostly prefers cell growth as well as increases production costs. This study aims to find the effect of low-cost inorganic nitrogen in the form of ammonium chloride on kojic acid production from fungal isolate Aspergillus sp. BU20S. A 3.63-times increase in the kojic acid (4.43 ± 0.47 g/L) was found when only the ammonium chloride was supplemented in glucose (10 g/L) medium than other minimal salts. The product formation was 2.52 ± 0.56 g/L in ammonium chloride as compared to 2.02 ± 0.06 g/L yeast extract after 10 days. The carbon/nitrogen ratio (C/N) was found optimal as 15 (molecular C/N: 23.58) which gives a high titer of 5.17 ± 0.84 g/L from 10 g/L of glucose. At this optimal molecular nitrogen value, the nitrogen supplement cost can be reduced by 93–99% compared to yeast extract. The antimicrobial potential of kojic acid purified from the fermented broth was also studied against methicillin-resistant Staphylococcus aureus (MRSA). The purified kojic acid showed a ~ 20 mm zone of inhibition at a 2.5 mg dose loaded over 7.4 × 109 CFU/mL of MRSA. This study concludes that only ammonium chloride is a sufficient inorganic nitrogen source to produce kojic acid and is useful in reducing production costs. The purified kojic acid is also an effective antimicrobial agent. [ABSTRACT FROM AUTHOR]

The restrictions for halal and vegetarian fermented products apply not only to the food ingredients, but also to the inoculum media. The utilization of a medium for lactic acid bacteria (LAB) leads to some issues from animal-derived proteins sources that may be doubtful for halal and/or vegetarian use. This study aimed to develop a plant-based medium for culturing and maintaining LAB. The result demonstrated that 10 g/L soybean powder in sweet potato extract was suitable for cultivating Lactiplantibacillus plantarum TISTR 2075 with no significant difference (p < 0.05) from MRS (de Man, Rogosa and Sharpe) in the cell number (9.12 log CFU/mL) and specific growth rate (0.04). The feasibility of a plant-based medium to grow and maintain the LAB strains from different origins was evaluated. Compared to MRS, Lpb. plantarum TISTR 2075, Lpb. plantarum MW3, and Lacticaseibacillus casei TISTR 1463 could grow almost as well in a plant-based medium. This medium was also suitable for maintaining the viability of LAB during storage, especially when subjected to slant agar stock culture. It is practical and costs at least 10 times less than MRS. Thus, this study created a low-cost plant-based medium that could be used in laboratories, especially for applications in halal and vegetarian food products. [ABSTRACT FROM AUTHOR]

In this study, sugarcane molasses (SCM) was pre-treated in a low-cost fermentation medium to produce probiotic biomass of Lactobacillus paracasei ssp. paracasei F19 (LPPF19) with the combination of dilution, centrifugation, and acid hydrolysis (5 molar sulfuric acid, 60 °C/2 h). Microtox analysis, inductively coupled mass spectrometry (ICP-MS), and high-performance liquid chromatography (HPLC) were used to measure the effects of SCM pretreatment on the fermentation process. The results showed that the hydrolysis of sucrose into glucose and fructose was 98%, which represented an increase of 44.4% in the initial glucose content (fermentation-limiting sugar), and harmful heavy metals, such as arsenic, cadmium, and lead, were reduced by 50.3, 60.0, and 64.3%, respectively. After pretreatment, with the supplementation of only yeast extract and salts (Na, K, Mg, and Mn), a biomass of 9.58 log CFU/mL was achieved, approximately ten times higher than that for the control medium used (MRS/DeMan, Rogosa, and Sharpe). The cost reduction achieved compared to this commercial medium was 68.7% in the laboratory and 78.9% on an industrial scale. This work demonstrated that SCM could be used in a cheaper and more effective alternative fermentation to produce LPPF19. [ABSTRACT FROM AUTHOR]

Bacterial nanocellulose was produced here using static, static intermittent-fed batch (SIFB) and rotary disc bioreactor (RDB) mode. Economical black tea broth media with symbiotic consortia of bacteria and yeast (SCOBY) was used towards feasible BNC production (instead of commercial NCIM 2526 strain and conventional HS media). The physicochemical characterization of BNC produced in all three modes via FE-SEM, ATR-FTIR, XRD and TGA results showed a highly porous morphology, mostly Iα form, good crystallinity and thermal stability, respectively. BNC crystallinity lies in the range of 68 % (RDB) to 79.4 % (static and SIFB). Water retention value (86 to 93 %) and moisture content (85 to 93 %) are high for BNC produced in all three modes. Commendable difference in the BNC yield, sugar consumption, conversion yield and residual sugar was observed using different methods. Highest BNC yield 29.4 ± 0.66 gL−1 was obtained under SIFB method as compared to static mode (13.6 ± 0.32 g L−1). Under RDB, a negligible amount of BNC i.e., 1.0 ± 0.2 g L−1 was produced. SCOBY with BTB medium was found unsuitable for BNC production under RDB and needs further investigation. Thus, this comparative study offers a way to produce a commendable amount of low-priced BNC for various techno-industrial usage. [Display omitted] [ABSTRACT FROM AUTHOR]

The restrictions for halal and vegetarian fermented products apply not only to the food ingredients, but also to the inoculum media. The utilization of a medium for lactic acid bacteria (LAB) leads to some issues from animal-derived proteins sources that may be doubtful for halal and/or vegetarian use. This study aimed to develop a plant-based medium for culturing and maintaining LAB. The result demonstrated that 10 g/L soybean powder in sweet potato extract was suitable for cultivating Lactiplantibacillus plantarum TISTR 2075 with no significant difference (p < 0.05) from MRS (de Man, Rogosa and Sharpe) in the cell number (9.12 log CFU/mL) and specific growth rate (0.04). The feasibility of a plant-based medium to grow and maintain the LAB strains from different origins was evaluated. Compared to MRS, Lpb. plantarum TISTR 2075, Lpb. plantarum MW3, and Lacticaseibacillus casei TISTR 1463 could grow almost as well in a plant-based medium. This medium was also suitable for maintaining the viability of LAB during storage, especially when subjected to slant agar stock culture. It is practical and costs at least 10 times less than MRS. Thus, this study created a low-cost plant-based medium that could be used in laboratories, especially for applications in halal and vegetarian food products.

In this study, sugarcane molasses (SCM) was pre-treated in a low-cost fermentation medium to produce probiotic biomass of Lactobacillus paracasei ssp. paracasei F19 (LPPF19) with the combination of dilution, centrifugation, and acid hydrolysis (5 molar sulfuric acid, 60 °C/2 h). Microtox analysis, inductively coupled mass spectrometry (ICP-MS), and high-performance liquid chromatography (HPLC) were used to measure the effects of SCM pretreatment on the fermentation process. The results showed that the hydrolysis of sucrose into glucose and fructose was 98%, which represented an increase of 44.4% in the initial glucose content (fermentation-limiting sugar), and harmful heavy metals, such as arsenic, cadmium, and lead, were reduced by 50.3, 60.0, and 64.3%, respectively. After pretreatment, with the supplementation of only yeast extract and salts (Na, K, Mg, and Mn), a biomass of 9.58 log CFU/mL was achieved, approximately ten times higher than that for the control medium used (MRS/DeMan, Rogosa, and Sharpe). The cost reduction achieved compared to this commercial medium was 68.7% in the laboratory and 78.9% on an industrial scale. This work demonstrated that SCM could be used in a cheaper and more effective alternative fermentation to produce LPPF19.

Bio-based 2,3-butanediol (2,3-BDO) viability production on a large scale depends on the culture medium costs, fermentation broth, and bioprocess biosafety. This study investigated sugarcane molasses, corn steep liquor, and ammonium chloride to replace commercial glucose and yeast extract for 2,3-BDO production by a safe and wild-type Paenibacillus peoriae NRRL BD-62. A savings of 75.2% were achieved using sugarcane molasses and NH 4 Cl-based medium, whose final cost was 4.74 US$/kg2,3-BDO. Levo -2,3-BDO was produced with high optical purity and no acetoin accumulation in batch fermentation. The selectivity was maintained above 90% in fed-batch fermentation at constant feeding. In contrast, the yield showed a 20% reduction, indicating that this feeding strategy was less efficient than batch cultures. To the best of our knowledge, this is the first time that levo -2,3-BDO with high optical purity has been produced by a newly isolated P. peoriae strain from sugarcane molasses in a low-cost salt medium, making the large-scale process sustainably promising. [Display omitted] • First time that 2,3-BDO was produced by a P. peoriae strain from sugarcane molasses. • An inexpensive and chemically defined ammonium chloride-based medium was used. • Levo -2,3-BDO with high optical purity was produced with no acetoin accumulation. • Batch culture was more suitable for 2,3-BDO production from non-pretreated molasses. • A culture medium saving of 75.2% was achieved, with a final cost of 4.74 US$/kg 2,3-BDO. [ABSTRACT FROM AUTHOR]

A synthetic medium containing glucose, glycerol, yeast extract (YE), and ammonium sulfate (AS) was compared to several low-cost media in their ability to produce high emulsification index (EI). The goal was to reduce the production costs of an emulsifier with application in food oil-in-water emulsions. To this end, agro-industrial by-products were screened for bioemulsifier production from Yarrowia lipolytica. The statistical analysis showed that the EIs of media containing residual frying oil from palm oil (RFO_palm) or soybean oil (RFO_soy), residual liquid from butter production (butter whey, BWhey) or cheese production (cheese whey, CWhey), supplemented with YE and AS were similar to the EI of the synthetic medium. The replacement of YE by corn steep liquor (CSL) also resulted in similar EI, except for RFO_soy. BWhey was tested with CSL without AS and similar EI (66.8%) was detected in comparison to that of the same medium with AS (66.3%). The cell-free broth obtained after Y. lipolytica growth in BWhey+CSL was successfully used to obtain vegetable oil-in-water emulsions indicating its potential application in food products. [ABSTRACT FROM AUTHOR]

ABSTRACT: A synthetic medium containing glucose, glycerol, yeast extract (YE), and ammonium sulfate (AS) was compared to several low-cost media in their ability to produce high emulsification index (EI). The goal was to reduce the production costs of an emulsifier with application in food oil-in-water emulsions. To this end, agro-industrial by-products were screened for bioemulsifier production from Yarrowia lipolytica. The statistical analysis showed that the EIs of media containing residual frying oil from palm oil (RFO_palm) or soybean oil (RFO_soy), residual liquid from butter production (butter whey, BWhey) or cheese production (cheese whey, CWhey), supplemented with YE and AS were similar to the EI of the synthetic medium. The replacement of YE by corn steep liquor (CSL) also resulted in similar EI, except for RFO_soy. BWhey was tested with CSL without AS and similar EI (66.8%) was detected in comparison to that of the same medium with AS (66.3%). The cell-free broth obtained after Y. lipolytica growth in BWhey+CSL was successfully used to obtain vegetable oil-in-water emulsions indicating its potential application in food products.

Bacillus thuringiensis subspecies israelensis (Bti) has been used as a mosquito control agent in agricultural field and residences. The production of Bti by conventional medium was expensive. The objective of this study was to investigate low-cost media for Bti’s production with a cost analysis of the medium formulated. Soybean Casein Digest Medium (TSB) was used as a conventional medium to compare with Saberi medium at room temperature (approximately 21.5˚C) on static and agitation (by obituary shaker at 100 rpm). Saberi medium was also modified to vary the percentage of nitrogen and carbon source to observe the growth rate and sporulation, compared to the Saberi medium. The growth of Bti in TSB with agitation for 24 hours yielded the highest growth rate. Sporulation of Bti in TSB with agitation at room temperature was 6 days which was faster than Bti in the Saberi medium. Modified Saberi nitrogen source and carbon source medium could not support the growth of Bti due to an imbalance in the percentage of nitrogen source and carbon source. Determination of sugar utilization showed sugar in the medium was utilized mostly in the exponential phase of Bti, from 3 hours to 6 hours. The price of TSB was 76.80 Thai baht per liter while Saberi medium’s cost was 20.43 Thai baht per liter. In this study, the Saberi medium may not be able to replace TSB in terms of growth rate and period of sporulation. Further study will be needed to optimize the media that use agro-industrial wastes as ingredients following the concept of circular economy and sustainability.

To valorize starchy waste from rice noodle factory, bioconversion of gelatinized starchy waste (GSW) to value-added product as L(+)-lactic acid, the monomer for polylactate synthesis, was investigated using amylolytic lactic acid bacterium, Enterococcus faecium K-1. Screening for appropriate nitrogen source to replace expensive organic nitrogen sources revealed that corn steep liquor (CSL) was the most suitable regarding high efficacy for L(+)-LA achievement and low-cost property. The successful applying statistic experimental design, Plackett-Burman design incorporated with central composite design (CCD), predicted the maximum L(+)-LA of 93.07 g/L from the optimized medium (OM) containing 125.7 g/L GSW and 207.3 g/L CSL supplemented with CH3COONa, MgSO4, MnSO4, K2HPO4, CaCl2, (NH4)2HC6H5O7, and Tween80. Minimizing the medium cost by removal of all inorganic salts and Tween80 from OM was not an effect on L(+)-LA yield. Fermentation using the optimized medium without minerals (OM-Mi) containing only GSW (125.7 g/L) and CSL (207.3 g/L) in a 10-L fermenter was also successful. Thinning GSW with α-amylase from Lactobacillus plantarum S21 increased L(+)-LA productivity in the early stage of 24-h fermentation. Not only showing the feasible bioconversion process for GSW utilizing as a substrate for L(+)-LA production, this research also demonstrated the efficient model for industrial starchy waste valorization. [ABSTRACT FROM AUTHOR]

Bio‐based 1,3‐propanediol demand has increased in recent years; however, its production costs are still not competitive in some markets. In this study, Plackett–Burman designs were used to cost medium reduction and 1,3‐propanediol production improvement with Clostridium butyricum. A simple culture medium for 1,3‐propanediol production from crude glycerol using the strain C. butyricum NCIMB 8082 was obtained by eliminating nine components of the usual culture medium. A 5 L fermentation using this simple culture medium was carried out in two steps. The final 1,3‐propanediol concentration was 73.07 g.L−1, achieving a productivity of 3.7 g.L−1.h−1 during the fed‐batch step. The low‐cost medium resulted in a 37% reduction in culture medium cost and a saving of 31% per kg for 1,3‐propandiol produced in comparison with other non‐complex media for 1,3‐propanediol production from crude glycerol reported in the literature © 2020 Society of Chemical Industry and John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Phenyl lactic acid (PLA) is an antimicrobial agent with a broad antimicrobial spectrum produced mainly by lactic acid bacteria. This study focused in the optimization of a low-cost medium to obtain biomass and PLA production by Pediococcus (Ped.) acidilactici CRL 1753 strain and propose its use as a liquid bio-preserver in bread making to increase the shelf life of wheat bread. First, the activity of CRL 1753 strain against filamentous fungi and yeasts was study and a wide antifungal inhibitory spectrum was observed. Using a factorial design 2 9-5 an optimized and low-cost medium (10 g/L meat peptone, 5 g/L yeast extract, 10 g/L glucose, 0.0038 g/L MnSO 4 , 6 g/L K 2 HPO 4 and initial pH = 7.0) that could replace MRS was obtained. A significant increase in shelf life was observed when calcium propionate (CP) and CRL 1753 strain were combined into the bread formulation. In fact, at 18 days of storage none moulds were observed when the liquid bio-preserver was added while 70% of breads were spoilage with CP alone. In this work we report for the first time the obtaining of an optimized low-cost culture medium for biomass and PLA production by Ped. acidilactici strain. The results obtained could be very useful as a basis to design new strategies that allow improve the PLA production at a low cost. [ABSTRACT FROM AUTHOR]

The present study aims to maximize proteases production by Bacillus mojavensis SA strain and their use to produce bioactive protein hydrolysates from a meat by-product. The production of SA bacteria proteases was maximized using a culture medium based on wheat bran, which offer an advantage in minimizing the production cost and enhancing the enzyme activity by using agro-industrial wastes. The composition of media and cultural conditions for optimal proteases production by B. mojavensis SA strain were investigated. A successful and significant improvement of the alkaline proteases production (four folds) by the SA strain was achieved using the medium composed of (g/l): wheat bran, 50.0; KH2PO4, 0.5; K2HPO4, 0.5; CaCl2, 2.0; pH 6.0, where the growth conditions were monitored at 37 °C with an agitation speed of 200 rpm. Interestingly, the enzyme preparation of B. mojavensis was applied for the preparation of protein hydrolysates from a meat by-product. Hydrolysis was carried out for 180 min at pH 12.0. The resulting hydrolysate displayed an important antioxidant activity as evaluated by the radical scavenging capacity, the reducing power, and the β-carotene bleaching inhibition. The present study showed the high proteases’ producing level by B. mojavensis SA strain in a low-cost fermentation medium (wheat bran) and their potential use in the production of bioactive protein hydrolysate from meat by-products. [ABSTRACT FROM AUTHOR]

Bioflocculants are needed to replace fossil-fuel based flocculants for industrial applications. This mini-review highlights the recent research trends on bioflocculant production from isolated strains. The bioflocculant research studies are addressing the search of effective strains that can be cultivated in low-cost medium with maximum bioflocculant production rates. Also, the search of auto-flocculating strains that can be harvested in seawaters is also an attractive research topic. The extracellular polymeric substances extracted from waste sludge biomass can be an effective bioflocculant in use. Another research trend is to use bioflocculant as the template of synthesis of novel materials. Since most bioflocculant studies had applied phosphate buffers for pH control, since the phosphate salts in fermentation broth can have flocculating activities, the reported efficiencies of the so-generated bioflocculants may be overestimated. The control tests to isolate the interference role of added ingredients in the fermenting broth are advised. [ABSTRACT FROM AUTHOR]

The production of exo-polygalacturonase (exo-PG) from orange peel (OP), a food industrial waste, using Aspergillus sojae was studied in submerged culture. A simple, low-cost, industrially significant medium formulation, composed of only OP and (NH)SO (AS) was developed. At an inoculum size of 2.8 × 10 spores/mL, growth was in the form of pellets, which provided better mixing of the culture broth and higher exo-PG activity. These pellets were successfully used as an inoculum for bioreactors and 173.0 U/mL exo-PG was produced. Fed-batch cultivation further enhanced the exo-PG activity to 244.0 U/mL in 127.5 h. The final morphology in the form of pellets is significant to industrial fermentation easing the subsequent downstream processing. Furthermore, the low pH trend obtained during this fermentation serves an advantage to fungal fermentations prone to contamination problems. As a result, an economical exo-PG production process was defined utilizing a food industrial by-product and producing high amount of enzyme. [ABSTRACT FROM AUTHOR]

Interest in bacterial pigments such as prodigiosin is growing among researchers due to their antibacterial, antifungal, antiproliferative and immunosuppressive properties. However, commercial application of bacterial-based pigments such as prodigiosin is limited due to the high production cost, which is partly caused by the expensive growth medium. This study reports on the use of brown sugar for the growth of a locally isolated, red-pigment (prodigiosin)-producing bacterium, i.e. Serratia marcescens UTM1. Factors affecting prodigiosin production – notably culture conditions and the effect of lactose and L- tryptophan supplementation – were evaluated in both shake-flask and 5-l bioreactor conditions. The use of optimized conditions resulted in a high prodigiosin yield of ∼8000 mg l −1 . The TLC and column chromatography-purified fraction was confirmed as prodigiosin using FTIR, LC-MS and NMR. This study demonstrates the feasibility of using brown sugar as a potential cheap growth medium for large-scale cultivation of prodigiosin using locally isolated S. marcescens UTM1. [ABSTRACT FROM AUTHOR]

Highlights: [•] A unique CO2 conversion technology using microorganisms was demonstrated. [•] Corn steep liquor medium enhanced production of n-butanol and n-hexanol. [•] Cotton seed extract (CSE) medium promoted ethanol formation. [•] CSE medium without morpholinoethanesulfonic acid buffer reduced the cost by 99%. [ABSTRACT FROM AUTHOR]

One of the most important challenges facing the Spirulina mass cultivation industry is to find a way to reduce the high production costs involved in production. Although the most commercial medium (Zarrouk's medium) for Spirulina cultivation is too expensive to use, it contains higher amount of NaHCO3 (16.80 g L-1), trace metals and vitamin solutions. The purpose of this study was to increase the efficiency of Spirulina platensis biomass production by developing a low-cost culture medium at an isolated tropical island such as Chuuk State, Federated States of Micronesia (FSM). This study set out to formulate a lowcost medium for the culture of S. platensis, by substituting nutrients of Zarrouk's medium using fertilizer-grade urea and soil extract with a different concentration of carbon source under natural weather condition. In order to select a low-cost culture medium of S. platensis, 10 culture media were prepared with different concentrations of nitrogen (urea and NaNO3) and NaHCO3. The highest maximum specific growth rate (µmax) and mass production were 0.50 day-1 and 1.05 g L-1 in modified medium (NaHCO3 7.50 g L-1, urea 2.00 g L-1 without NaNO3) among all the synthesized media. Protein (56.14%) and carbohydrate (16.21%) concentrations of the lyophilized standard samples were estimated with highest concentration of glutamic acid (14.93%). This study revealed that the use of a low concentration of urea and NaHCO3 with soil extract was an affordable medium for natural mass cultivation in the FSM. [ABSTRACT FROM AUTHOR]

Highlights: [•] A novel microbial flocculants (MBF) was produced from a new strain. [•] The MBF can flocculate strong alkaline trona suspension. [•] The MBF can be produced using the waste from food industry as low-cost medium. [ABSTRACT FROM AUTHOR]

5-Aminolevulinic acid (ALA) is an intermediate in the biosynthesis of tetrapyrroles. Its current production is expensive. We have developed a low-cost medium for Propionibacterium acidipropionici to produce extracellular ALA. When grown at 35 °C on a medium containing 3 % (w/v) food-grade sodium lactate supplemented with 18 g glycine/l, 4.05 g succinate/l, 1.8 g glucose/l, pH 7, it produced ALA up to 7.7 g/l over 6 days. Plant-growth promoting activity assays showed that the ALA was biologically active. [ABSTRACT FROM AUTHOR]

A critical component of an in vitro production process for baculovirus biopesticides is a growth medium that is efficacious, robust, and inexpensive. An in-house low-cost serum-free medium, VPM3, has been shown to be very promising in supporting Helicoverpa armigera nucleopolyhedrovirus (HaSNPV) production in H. zea insect cell suspension cultures, for use as a biopesticide against the Heliothine pest complex. However, VPM3 is composed of a significant number of undefined components, including five different protein hydrolysates, which introduce a challenging lot-to-lot variability to the production process. In this study, an intensive statistical optimization routine was employed to reduce the number of protein hydrolysates in VPM3 medium. Nearly 300 runs (including replicates) were conducted with great efficiency by using 50 mL TubeSpin® bioreactors to propagate insect cell suspension cultures. Fractional factorial experiments were first used to determine the most important of the five default protein hydrolysates, and to screen for seven potential substitutes for the default meat peptone, Primatone RL. Validation studies informed by the screening tests showed that promising alternative media could be formulated based on just two protein hydrolysates, in particular the YST-AMP (Yeast Extract and Amyl Meat Peptone) and YST-POT (Yeast Extract and Lucratone Potato Peptone) combinations. The YST-AMP (meat-based) and YST-POT (meat-free) variants of VPM3 were optimized using response surface methodology, and were shown to be just as good as the default VPM3 and the commercial Sf-900 II media in supporting baculovirus yields, hence providing a means toward a more reproducible and scalable production process for HaSNPV biopesticides. © 2012 American Institute of Chemical Engineers Biotechnol. Prog.,, 2012 [ABSTRACT FROM AUTHOR]

For low-cost production of Photorhabdus temperata ssp. temperata strain K122 bioinsecticide, a cheap complex medium was optimized. Diluted seawater was used as the source of micronutrients, especially sodium chloride, involved in the improvement of cell density, culturability and oral toxicity of the bacterium P. temperata against Ephestia kuehniella larvae. Thus, the new formulated medium was composed only of 10 g/l of soya bean meal, used as the carbon and nitrogen main source, mixed in sevenfold diluted seawater. At such conditions, several limitations of P. temperata bioinsecticide productions were shown to be overcome. The appearance of variants small colony polymorphism was completely avoided. Thus, the strain K122 was maintained at the primary form even after prolonged incubation. Moreover, the viable but nonculturable state was partially overcome, since the ability of P. temperata cells to form colonies on the solid medium was prolonged until 78 h of incubation. In addition, when cultured in the complex medium, P. temperata cells were produced at high cell density of 12 × 10 cells/ml and exhibited 81.48% improvement of oral toxicity compared to those produced in the optimized medium. With such medium, the large-scale bioinsecticides production into 3-l fully controlled fermenter improved the total cell counts, CFU counts and oral toxicity by 20, 5.81 and 16.73%, respectively. This should contribute to a significant reduction of production cost of highly potent P. temperata strain K122 cells, useful as a bioinsecticide. [ABSTRACT FROM AUTHOR]

Abstract: The use of cellulosic biosludges generated in a Kraft pulp mill was investigated as substrate for lactic acid production by simultaneous saccharification and fermentation (SSF). The effect of the operation mode (batch or fedbatch), the initial liquid to solid ratio (12 or 30g/g) and the nutrient supplementation (MRS components or none) on several parameters including lactic acid concentration, volumetric productivity and product yields, were evaluated. When the operation was carried out in fedbatch mode with nutrient supplementation and using a LSR0 =12g/g, a broth containing 42g/L was obtained after 48h with a volumetric productivity of 0.87g/Lh and a product yield of 37.8g lactic acid/100g biosludges. In a similar experiment carried out without nutrient supplementation, a lactic acid concentration of 39.4g/L was obtained after 48h with a volumetric productivity of 0.82g/Lh and a product yield of 35.5g l-lactic acid/100g biosludges. [Copyright &y& Elsevier]

Abstract: A new medium was formulated for mass production of Spirulina sp. by incorporating selected nutrients of the standard Zarrouk''s medium (SM) and other cost-effective alternative chemicals. This newly formulated medium (RM6) contains single super phosphate (1.25gl−1), sodium nitrate (2.50gl−1), muriate of potash (0.98gl−1), sodium chloride (0.5gl−1), magnesium sulphate (0.15gl−1), calcium chloride (0.04gl−1), and sodium bicarbonate (commercial grade) 8gl−1. The alga was grown in an illuminated (50μmolphotonsm−2 s−1 white light) growth room at 30±1°C. Maximum growth rate in terms of dry biomass, chlorophyll and proteins in SM was recorded between 6 and 9 days of growth and values were 0.114, 0.003 and 0.068 as compared to 0.112, 0.003 and 0.069mgml−1 d−1 in RM6,. No significant differences were observed in the protein profiles of Spirulina sp. grown in both the media. From the scale up point of view, the revised medium was found to be highly economical, since it is five times cheaper than Zarrouk''s medium. [Copyright &y& Elsevier]

Astaxanthin production in the wild strain Xanthophyllomyces dendrorhous TISTR 5730 was investigated using different mustard waste media, including mustard waste residue extract (MRE), mustard waste residue hydrolysate (MRH), mustard waste precipitated extract (MPE), and mustard waste precipitated hydrolysate (MPH). The growth of X. dendrorhous and the production of astaxanthin were dependent on the type and initial concentrations of mustard waste media. The MPH medium was the best substrate resulting in yields of biomass and astaxanthin of 19.6 g/L and 25.8 mg/L, respectively, under optimal conditions. MPH medium improved astaxanthin production 11-fold compared to the commonly used commercial yeast malt medium, and 1.3–2.1-fold compared to other mustard waste media. [ABSTRACT FROM AUTHOR]

Microalgae are appraised as the renewable feedstock for biodiesel production. With this view, the current study examines the possibility of a locally isolated microalga, Chlorella minutissima for production of biodiesel, under batch and fed-batch cultivation modes, being subjected to seasonal variations. Effects of different culture depths (5, 10, 15, and 20 cm) on the biomass yield and lipid accumulation were investigated using the mini pond system, and alterations in different physicochemical factors were documented. Both the batch as well as the fed-batch cultivations recorded the 15 cm culture depth to be optimum for obtaining the maximum biomass and lipid production. Consequently, this optimal depth was chosen for further experimentation integrating low-dose sequential phosphate addition (LDSPA) under both batch and fed-batch modes. For batch cultivation under LDSPA mode, the estimated annual biomass productivity was 10.04 ton hectare−1 year−1, with the lipid productivity of 1.37 ton hectare−1 year−1, considering 11 cycles of cultivation per year. On the other hand, the fed-batch cultivation under LDSPA mode projected the annual biomass productivity of 15.4 ton hectare−1 year−1 and lipid productivity of 2.29 ton hectare−1 year−1, even with 10 cycles of cultivation yearly, thus, certifying the supremacy of the fed-batch cultivation with LDSPA for obtaining a higher productivity of lipid. The biodiesel generated from the produced biomass demonstrated a greater prevalence of monounsaturated and saturated fatty acid methyl esters. Additionally, the fuel characteristics of the biodiesel samples were analyzed and recorded to be at par with the national (Indian) as well as international (European and American) biodiesel standards, hence, indicating its suitability as an alternative to petroleum-based fuel. • Indigenous Chlorella minutissima was explored at outdoor for biodiesel production. • 15 cm was found optimum culture depth for maximum biomass and lipid production. • Low-dose sequential phosphate additions boosted lipid productivity significantly. • Lipid productivity of 2.29 ton hectare−1 year−1 under fed-batch mode was observed. • Fuel properties were found to be within the limits of various biodiesel standards. [ABSTRACT FROM AUTHOR]

The plant growth-promoting rhizobacterial strain Pseudomonas putida Rs-198 was isolated from salinized soils from Xinjiang Province. We optimized the composition of the low-cost medium of P. putida Rs-198 based on its bacterial concentration, as well as its phosphate-dissolving and indole acetic acid (IAA)-producing capabilities using the response surface methodology (RSM), and a mathematical model was developed to show the effect of each medium component and its interactions on phosphate dissolution and IAA production. The model predicted a maximum phosphate concentration in medium containing 63.23 mg/L inorganic phosphate with 49.22 g/L corn flour, 14.63 g/L soybean meal, 2.03 g/L K₂HPO₄, 0.19 g/L MnSO₄ and 5.00 g/L NaCl. The maximum IAA concentration (18.73 mg/L) was predicted in medium containing 52.41 g/L corn flour, 15.82 g/L soybean meal, 2.40 g/L K₂HPO₄, 0.17 g/L MnSO₄ and 5.00 g/L NaCl. These predicted values were also verified through experiments, with a cell density of 10(13) cfu/mL, phosphate dissolution of 64.33 mg/L, and IAA concentration of 18.08 mg/L. The excellent correlation between predicted and measured values of each model justifies the validity of both the response models. The study aims to provide a basis for industrialized fermentation using P. putida Rs-198.