Low-cost Culture Research Articles

Development of a low-cost cultivation medium for simultaneous production of biodiesel and bio-crude from the chlorophycean microalga Tetradesmus obliquus: A renewable energy prospective

Microalgal biodiesel production experiences hurdles in every step, beginning from cultivation of microalgal strains for biomass generation followed by harvesting, drying, oil extraction, and transesterification, leading to higher cost of production. In this study, an approach was adopted to minimize the cost of biomass production by utilizing the locally available agricultural fertilizers, viz. urea, NPK 10 26 26, diammonium phosphate, potash, superphosphate, etc. for cultivation of the green microalga Tetradesmusobliquus that can be subsequently used for biodiesel and bio-crude production. For this, an optimized urea medium (OUr) was developed, which reduced the cost of production by 47-fold as compared to the commonly used N 11 medium, formulated with the analytical grade inorganic salts. This optimized medium further enhanced the biomass yield by 32% while reducing the requirements of the major nutrients like potash, magnesium sulfate and superphosphate by 29, 25 and 25%, respectively. Urea requirement was, however, increased by 20%. Raceway pond cultivation of T. obliquus in the newly formulated medium depicted a biomass productivity of 12.6 g m−2 day−1 during winter season followed by 10. 9 g m−2 day−1 in summer and 4.8 g m−2 day−1 in rainy season at a culture depth of 30 cm, thus leading to an estimated biomass productivity of 30.04 ton hectare−1 year−1,and a biodiesel productivity of 2.07 ton hectare−1 year−1. The fuel characteristics of the biodiesel produced showed comparable characteristics with petro-diesel, and were also within the limits specified by the national and international standards. Bio-crude productivity of 10 ton hectare−1 year−1 was projected from the de-fatted biomass. This study was thus successful in utilizing >40% of the biomass for simultaneous production of biodiesel and bio-crude from the same biomass, eventually paving a path for the development of a microalgal refinery by exploring the spent biomass for further applications.

Improved low-cost tissue culture method as an alternative to high-tech micropropagation for Musa spp.

Improved low-cost tissue culture method as an alternative to high-tech micropropagation for Musa spp.

Evaluation of Sugar Mill By-product Molasses as a Low Cost Culture Media for Microalgae

Microalga Chlorella vulgaris was cultured in different concentrations of normal molasses medium (NMM0.5 g/l, NMM1.0 g/l, and NMM1.5 g/l) to evaluate growth performance of the sugar mill byproduct as a low cost culture media and Bold basal medium (BBM) as control. Maximum growth of Chlorella vulgaris was found in NMM 1.0 g/l on 8th day of the culture followed by BBM, NMM 0.5 g/l and NMM 1.5 g/l. Similar findings were also observed in determining chlorophyll a content and optical density of C. vulgaris. Maximum cell growths 191.88 (Χ 105)/mL, chlorophyll a content 10.60 (mg/l) and optical density 2.15 were recorded in NMM1.0 g/l. Maximum SGR of cell was determined 0.56 (mg/day) grown in NMM1.0 g/l followed by 0.52, 0.52 and 0.48 (mg/day) in BBM, NMM0.5 g/l and NMM1.5 g/l, respectively. Chlorophyll a content and total biomass of Chlorella vulgaris followed the similar trend. Protein (46.49%) and lipid (14.18%) of C. vulgaris was detected significantly higher (P<0.01) in NMM1.0 g/l than that grown in BBM and other concentrations of NMM. The growth performance of the investigating molasses medium (NMM1.0 g/l) indicates that the molasses may be a good low cost culture medium ingredient source for C. vulgaris or any other microalga species.

Assessing the potential of Schizochytrium sp. HX-308 for microbial lipids production from corn stover hydrolysate.

Schizochytrium sp. has received increasing attention as promising commercial resource for the sustainable production of lipids, due to their fast growth rate and high lipid content. However, the price of glucose represents a significant proportion of the total substrate cost. Therefore, in this study, the lignocellulosic hydrolysate of corn stover hydrolysate (CSH) was used as low-cost culture medium to replace glucose in Schizochytrium sp. fermentation. When Schizochytrium sp. HX-308 was fermented with 20% glucose from CSH and 80% of glucose from pure glucose, the lipid production reached 21.2gL-1 , which is lower than that of using 100% of pure glucose. However, the shifts of fatty acid composition indicated that CSH has great potential to enhance the percentage of polyunsaturated fatty acids (PUFAs) in total lipids. However, as the second largest carbon source in CSH, xylose was not utilized by the Schizochytrium sp. HX-308, and further analysis showed that probably because it does not possess a functional xylulose kinase. In addition, the degradation products in lignocellulosic hydrolysate have a strong inhibitory effect on cell growth, so it is necessary to investigate the tolerance of Schizochytrium sp. HX-308 to degradation products. Here, the effects of five typical degradation products on the growth and lipid synthesis were further investigated. Schizochytrium sp. HX-308 showed good tolerance to furan derivatives and organic acids, but low tolerance to phenolic compounds. Furthermore, in order to improve the lipid accumulation using CSH, the two-stage fermentation strategy was developed, resulting in a 54.8% increase compared to that of the one-stage strategy. In summary, this study provides a reference for further fermentation engineering with cheap lignocellulosic biomass as substrate.

ASSESSMENT OF GROWTH PARAMETERS OF SPIRULINA (Spirulina Platensis) USING DIGESTED ROTTEN MANGO (Mangifera Indica) SUPERNATANT AS A COSTEFFECTIVE CULTURE MEDIA

The culture and growth performance of Spirulina platensis in three different concentrations (25, 50, and 75 percent) of digested rotten mango media (DRMM) and Kosaric medium (KM) as control were investigated. This study intended to examine DRMM as a low cost culture media for microalgae. For 16 days, optical density, cell weight, chlorophyll a concentration, and total biomass of S. platensis under various treatments were measured in every alternate day. The growth rate of S. platensis cultured in the supernatant of DRMM and KM was varied and the maximum cell weight, chlorophyll a content and total biomass of S. platensis were 0.085 mg/L, 0.08 mg/L and 4.824±0.021 mg/L at 50% in DRMM of the culture. This study showed that the growth performance of S. platensis was higher in the supernatant of 50% DRMM than 25 and 75% of DRMM which resulted satisfactorily compared with standard KM. In the supernatant of 50% digested rotten mango medium, large volume spirulina culture may be feasible.

Rhodosporidium toruloides and Tetradesmus obliquus Populations Dynamics in Symbiotic Cultures, Developed in Brewery Wastewater, for Lipid Production.

In this work, primary brewery wastewater (PBWW) and secondary brewery wastewater (SBWW) separately, or mixed at the ratios of 1:1 (PBWW:SBWW) and 1:7 (PBWW:SBWW), with or without supplementation with sugarcane molasses (SCM), were used as culture media for lipid production by a mixed culture of the oleaginous yeast Rhodosporidium toruloides NCYC 921 and the microalgae Tetradesmus obliquus (ACOI 204/07). Flow cytometry was used to understand the dynamics of the two micro-organisms during the mixed cultures evolution, as well as to evaluate the physiological states of each micro-organism, in order to assess the impact of the different brewery effluent media composition on the microbial consortium performance. Both brewery wastewaters (primary and secondary) without supplementation did not allow R. toruloides heterotrophic growth. Nevertheless, all brewery wastewater media, with and without SCM supplementation, allowed the microalgae growth, although the yeast was the dominant population. The maximum total biomass concentration of 2.17g L-1 was achieved in the PBWW mixed cultivation with 10g L-1 of SCM. The maximum lipid content (14.86% (w/w DCW)) was obtained for the mixed culture developed on SBWW supplemented with 10g L-1 of SCM. This work demonstrated the potential of using brewery wastewater supplemented with SCM as a low-cost culture medium to grow R. toruloides and T. obliquus in a mixed culture for brewery wastewater treatment with concomitant lipid production.

Use of products of vegetable origin and waste from hortofruticulture for alternative culture media

Conventional culture media are expensive owing to their constituents. Thus, several studies have sought to develop and evaluate the efficacy of alternative, low-cost culture media, in most cases, using natural and easily accessible raw materials. The present study is a literature review, observing various formulations of culture media based on products of plant origin for the growth of microorganisms and production of microbial compounds of industrial interest. In most formulations, vegetable substrates, such as soy, certain beans, corn, and rice, were used in addition to hortofruticultural products. Compared to conventional media, the alternative culture media often present satisfactory results in terms of microbial growth efficiency and production cost.

Microalgae-based bioplastics: Future solution towards mitigation of plastic wastes

Global demand for plastic materials has severely harm the environment and marine sea life. Therefore, bioplastics have emerged as an environmentally friendly alternative due to sustainability, minimal carbon footprint, less toxicity and high degradability. This review highlights the sustainable and environmentally friendly approach towards bioplastic production by utilizing microalgae as a feed source in several ways. First, the microalgae biomass obtained through the biorefinery approach can be processed into PHA under certain nutrient limitations. Additionally, microalgae biomass can act as potential filler and reinforcement towards the enhancement of bioplastic either blending with conventional bioplastic or synthetic polymer. The downstream processing of microalgae via suitable extraction and pre-treatment of bioactive compounds such as lipids and cellulose are found to be promising for the production of bioplastics. Moving on, the intermediate processing of bioplastic via lactic acid synthesized from microalgae has favoured the microwave-assisted synthesis of polylactic acid due to cost efficiency, minimum solvent usage, low energy consumption, and fast rate of reaction. Moreover, the reliability and effectiveness of microalgae-based bioplastics are further evaluated in terms of techno-economic analysis and degradation mechanism. Future improvement and recommendations are listed towards proper genetic modification of algae strains, large-scale biofilm technology, low-cost cultivation medium, and novel avocado seed-microalgae bioplastic blend.

Recent Advancements and Future Perspectives of Microalgae-Derived Pharmaceuticals.

Microalgal cells serve as solar-powered factories that produce pharmaceuticals, recombinant proteins (vaccines and drugs), and valuable natural byproducts that possess medicinal properties. The main advantages of microalgae as cell factories can be summarized as follows: they are fueled by photosynthesis, are carbon dioxide-neutral, have rapid growth rates, are robust, have low-cost cultivation, are easily scalable, pose no risk of human pathogenic contamination, and their valuable natural byproducts can be further processed. Despite their potential, there are many technical hurdles that need to be overcome before the commercial production of microalgal pharmaceuticals, and extensive studies regarding their impact on human health must still be conducted and the results evaluated. Clearly, much work remains to be done before microalgae can be used in the large-scale commercial production of pharmaceuticals. This review focuses on recent advancements in microalgal biotechnology and its future perspectives.

Growth and Biochemical Composition Characteristics of Arthrospira platensis Induced by Simultaneous Nitrogen Deficiency and Seawater-Supplemented Medium in an Outdoor Raceway Pond in Winter.

Arthrospira platensis, a well-known cyanobacterium, is widely applied not only in human and animal nutrition but also in cosmetics for its high amounts of active products. The biochemical composition plays a key role in the application performance of the Arthrospira biomass. The present study aimed to evaluate the growth and biochemical composition characteristics of A. platensis, cultured with a nitrogen-free and seawater-supplemented medium in an outdoor raceway pond in winter. The results showed that the biomass yield could achieve 222.42 g m−2, and the carbohydrate content increased by 247% at the end of the culture period (26 d), compared with that of the starter culture. The daily and annual areal productivities were 3.96 g m−2 d−1 and 14.44 ton ha−1 yr−1 for biomass and 2.88 g m−2 d−1 and 10.53 ton ha−1 yr−1 for carbohydrates, respectively. On the contrary, a profound reduction was observed in protein, lipid, and pigment contents. Glucose, the main monosaccharide in the A. platensis biomass, increased from 77.81% to 93.75% of total monosaccharides. Based on these results, large-scale production of carbohydrate-rich A. platensis biomass was achieved via a low-cost culture, involving simultaneous nitrogen deficiency and supplementary seawater in winter.

Mixotrophic Cultivation of Microalgae in Cassava Processing Wastewater for Simultaneous Treatment and Production of Lipid-Rich Biomass

Cassava processing wastewater (CPW) is a highly polluting, liquid residue of cassava processing, usually discarded or treated anaerobically. However, it can serve as a low-cost culture medium for microalgae. After a preliminary evaluation of the growth of 10 microalgal strains in diluted CPW, the microalgae Haematococcus pluvialis SAG 34−1b and Neochloris (Ettlia) oleoabundans UTEX 1185 were selected for cultivation in CPW without a supply of additional nutrients and evaluated for their growth, lipid production, and nutrients removal. Maximal biomass concentrations of 1.79 g·L−1 for H. pluvialis and 3.18 g·L−1 for N. oleoabundans were achieved with 25% CPW medium on the 13th day of growth. The algae H. pluvialis and N. oleoabundans removed 60.80 and 69.16% of the chemical oxygen demand, 51.06 and 58.19% of total nitrate, and 54.68 and 69.84% of phosphate, respectively. On average, lipid productivities reached 0.018 and 0.041 g·L−1 day−1 for H. pluvialis and N. oleoabundans, respectively. Therefore, cultivating these microalgae in diluted CPW is a promising treatment for cassava wastewater with simultaneous valuable biomass production.

Co-production of fucoxanthin and lipid from Indonesian diatom and green algae growing on palm oil mill effluent under mixotrophic condition

Recently, the mass scale production of fucoxanthin and fatty acid from microalgae has increased. However, a new and low cost cultivation strategy is needed to enhance the production. This work investigated the potency of mixed diatom and green algae isolated from Morosari Bay, Java Sea, Indonesia, to enhance the production of fucoxanthin and lipid by employing mixotrophic condition. A four stepwise experiment was done to study the environmental and nutritional factors, as well as to optimize the selected parameters by employing Box Behnken response surface methodology. The mixed algae was found to grow well on palm oil mill effluent (POME). Changing condition from autotrophic to mixotrophic decreased the pigment content. The highest fucoxanthin concentration (6 mg L−1) was found on the glycerol addition compared to other organic carbon sources. The optimal condition to produce 160 mg L−1 d−1 biomass and 60 mg L−1 d−1 lipid was found on 30% POME, supplemented with 3 g L−1 glycerol and 200 mg L−1 urea at 30 °C. Mono unsaturated fatty acid (MUFA) was the most dominant fatty acid class found in the mixed algae.

The Role of Paclobutrazol on Production Strategy of Curcuma alismatifolia Gagnep. for Off-Season Marketing

From September 2017 through February 2018, this open field research was conducted with 6 random treatments and 10 replications. Plants grown under sunlight source with paclobutrazol (PBZ) treatments were compared to those grown under sunlight plus 2 h night break (without PBZ) (control 1) and those grown under sunlight source (without PBZ) (control 2). The results showed that PBZ treatments lowered both height and peduncle length substantially. In comparison to control 1, the 600 mg/L PBZ treatment led in non-significant changes in physical growth and anthocyanin content in coma bract and fertile bract. Plants grown under sunshine + 2 h night break without PBZ had the shortest number of days to inflorescence appearance (day 46) and first flower opening (day 72). Plants cultivated under control 2 conditions had the largest delay in inflorescence emergence (day 61) and first flower opening (day 92). These findings will aid in the low-cost cultivation of C. alismatifolia cultivated in the open field during the off-season.

Melilot of the Caspian region and prospects of their conveyor use

The data of daily conveyor production of melilot hay, harvested mainly in early highly nutritious phases of development, branching and budding, are presented. Melilot, possessing a number of important advantages over other feed crops, nevertheless, are not popular among agricultural practitioners because of their coarse stems, low feed intake and high content of coumarin in plants. Undoubted advantages of melilot include: high yield of hay, haylage and green mass, seeds; salt tolerance and possibility of reclaiming saline lands without drainage and soil leaching; sun resistance; drought resistance; winter hardiness; low irrigation rate; high nutritional value and digestibility of feed; high protein content in plants; low cost cultivation; possibility of obtaining high yields without introduction of nitrogen fertilizers, unpretentiousness to soil fertility; excellent phytomeliorant and soil orderly; soil fertility restorer and excellent precursor for many crops. The varieties of melilot created for cultivation on saline lands of the Caspian Sea region provide an extension of conveyor period of pasture use and harvesting of their raw materials up to 188 days per season.

Biosynthesis and profiling of single cell carotenoids of Phaf ia rhodozyma in waste-based cultivation media

In order to investigate the feasibility of low-cost media for producing well- characterized single-cell carotenoid, the study on biosynthesis and profiling carotenoid in the yeast of Phaf ia rhodozyma was carried out. We have successfully identified the profiles of single-cell carotenoids of P. rhodozyma, which was cultivated in glucose-based medium (MG), molasses-based medium (MM), and coconut water-based medium (MC). Cells were separately cultured in those media under aerobic batch culture system to obtain the carotenoid profiles based on high performance liquid chromatography (HPLC) analysis. The results showed that medium composition strongly affects the profiles of P. rhodozyma carotenoids represented by ratio of astaxanthin and beta-carotene (ratio A/B). Astaxanthin was highly synthesized in cells cultivated in MG with ratio A/B as much of 20:1. On the other hand, MM and MC produced a lower ratio A/B than MG as much of 0.4:1 and 0.2:1, respectively. In addition, carotenoids profiles were detected more diverse when this yeast species was cultivated in two waste-based media. This study provided a basic physiological knowledge of P. rhodozyma cells for carotenoid biosynthesis using potential low cost cultivation m

Ethnobotany, phytochemistry, pharmacology, and toxicity of Centella asiatica (L.) Urban: A comprehensive review.

The well-known medicinal plant Centella asiatica (L.) Urban is an Ayurvedic and traditional Chinese medicine used in the treatment of different health problems and as an edible vegetable in a regular diet. Ease of availability in the wide range of environmental conditions plus low-cost cultivation process has made the plant popular in ethno-medicinal healthcare systems. In the present review, phytochemical analysis of plant-extract and pharmacological activities of bioactive-compounds are discussed based upon the available reports to understand their therapeutic potentialities along with the mechanisms behind. The results exhibited that C. asiatica and its triterpenoids demonstrated an array of pharmacological effects and health benefits, some of which were confirmed in many preclinical and clinical studies. Those reports also provided considerable evidences in support of the principles of folk treatment in different countries. Increase and maintenance of the prospective plant secondary metabolites would provide an enriched resource of drug molecules. Development of suitable derivatives of the therapeutic compounds can give an assurance for getting more effective drug candidates with reduced side effects. The review also enumerates the application of advanced nanotechnology, toxicology, and clinical-trial reports on the plant with notes on the shortcomings in the present research and future perspectives of using this medicinal plant.

STUDI PENGARUH MEDIA ALTERNATIF UNTUK PERBANYAKAN PISANG BARANGAN (Musa acuminata L.) SECARA IN-VITRO

The main obstacles in the commercialization of seedlings mass propagation through tissue culture techniques is the high cost of the culture media component. therefore, the production of lowcost tissue culture is required. This study aims to develop low cost in-vitro media for the production of the seedlings of Barangan banana. The research was composed following Factorial Completely Randomized Design, the first factor was Terra Novalgro liquid fertilizer with three concentrations, namely 1, 2, and 3 ml L-1, while the second factor was Gandasil with 3 concentrations namely 1, 2, and 3 mg L-1, so obtained nine treatments, each treatment was repeated 10 times, so that there were 90 experimental units. MS media was used as control. The parameter observed was number of shoots, number of leaves and number of roots. The results of this study exhibited that the treatment of 1 ml L-1 liquid fertilizer + 2 mg L-1 foliar fertilizer produced 9.30 shoots/explant and 1.90 leaves/explant, that no significantly different from MS medium (control) which produced 9.0 shoots/explant and 0.3 leaves/explants. Therefore, the using completed liquid fertilizers and foliar fertilizers as medium in vitro propagation of barangan bananas can become an alternative replace MS medium, as well as reduced the cost of culture media as 91% -93% compared to MS media.

A new and unusual β-glucosidase from Aspergillus fumigatus: Catalytic activity at high temperatures and glucose tolerance

The demand for novel enzymes with the potential to catalyze reactions at high temperatures has encouraged the exploration of new thermophilic strains in recent years. Several fungal thermophilic β-glucosidases have been described previously. However, only a few β-glucosidases meet industrial requirements, such as hydrolytic activity at high temperatures and tolerance to glucose inhibition. Because tropical areas support high species diversity, the Atlantic Forest biome can offer great opportunities for bioprospecting new β-glucosidase producers to fulfill industrial needs. This study reports the production and biochemical characterization of an unusual thermophilic β-glucosidase produced by an Aspergillus fumigatus strain isolated from the Atlantic Forest biome. This enzyme can be produced using a low-cost cultivation medium with canola meal as the substrate. The highest β-glucosidase production (24.53 U/mL) was obtained when the fungus was cultivated in 2.9% canola meal over a period of 101 h at pH 4.2, and a temperature of 40 °C. This enzyme has an optimum temperature of 80 °C, which is higher than that of almost all its known fungal counterparts. Moreover, it is highly glucose tolerant, unlike other β-glucosidases that are inhibited by this sugar, with an inhibitory constant (Ki) of 543 mM. The combination of these attributes and their sustained activity at 80 °C distinguishes this enzyme from other A. fumigatus enzymes and almost every other β-glucosidase characterized from thermotolerant fungal species described to date. Therefore, this novel enzyme is a promising target for bioethanol production. • A new A. fumigatus thermophilic and cellulolytic strain was isolated. • Canola meal was used as the carbon source to produce β-glucosidases. • Overall the process was effective in terms of β-glucosidase yield. • An unusual fungal β-glucosidase with maximum activity at 80 °C is described. • The enzyme is highly glucose tolerant with an inhibitory constant (Ki) of 543 mM.

Bioinoculant production composed by Pseudomonas sp., Serratia sp., and Kosakonia sp., preliminary effect on Allium cepa L., growth at plot scale

Phosphorus (P) is an essential nutrient for plant’s development, and its deficiency restricts crop yield. To meet P requirements in agricultural settings, a low-cost culture medium (MT11B) was designed in which a bioinoculant was produced consisting of three bacterial isolates capable of solubilizing P from phosphoric rock (PR). Pseudomonas sp., Serratia sp., and Kosakonia sp. exhibited P solubilization in SMRS1 agar modified with PR (5.0 g L-1), as source of inorganic P. Sowings by isolation were made of the three bacteria on DNAse- and Blood-agar to rule out pathogenicity. At the interaction tests, no inhibition halos were observed; demonstrating there was no antagonism among them, thus they were used to constitute a consortium. Growth curve (12 h) in MT11B demonstrated consortium grew in presence of PR, brewer’s yeast hydrolysate, and glucose at concentrations (2.5 g L-1) fourfold lower than those in SMRS1 (10.0 g L-1); obtaining phosphate solubilizing bacteria of (10.60 ± 0.08/ log10 CFUmL-1 and, at 6 h of culture, acid and alkaline phosphatase enzyme volumetric activities of 2.3 ± 0.8 and (3.80 ± 0.13) UP, respectively. The consortium, releasing phosphorus at a rate of (45.80 ± 5.17) mg L-1 at 6 h of production, was evaluated as bioinoculant in onion plots for five months. Plants receiving a treatment that included 500 mL (10 x 107 CFU mL-1) of bioinoculant plus 100 kg ha-1 of an organic mineral fertilizer exhibited the highest determined response variables (170.1 ± 22.2) mm bulb height, (49.4 ± 6.5) mm bulb diameter, (9.0 ± 1.8) g bulb dry weight, and 15.21 mg bulb-1 total phosphorus (p < 0.05).

A new model of Algal Turf Scrubber for bioremediation and biomass production using seaweed aquaculture principles

An increase in the use of macroalgal biomass for different applications is required in development of efficient cultivation systems and low-cost culture media. With this in mind, the present work proposes modifications to the Algal Turf Scrubber (ATS) system inducing the establishment of a monospecific culture of Ulva ohnoi through a seeding process, speeding up the maturation time and increasing efficiency and productivity. Bench-scale units of Seeded Algal Turf Scrubber (sATS) were built to test different types of algal attachment substrates (nylon and jute fiber) and water flow conditions (stagnant and continuous) besides evaluating of coverage rate, daily growth rate, and nutrient removal capacity. The results were promising. The coverage rate by U. ohnoi seedlings was higher when nylon substrate was combined with continuous water flow (74.41 ± 6.79%). Changes in nutrient concentration demonstrated a dose-dependent pattern with complete removal of P-PO43− in 24 h at all concentrations tested when the system had 18 days of maturation and N-NH4+ was completely removed in 24 h at all concentrations tested in both maturation times (18 and 47 days). Daily growth rates presented satisfactory values, reaching maximum of 4.8 ± 0.6% day−1. In conclusion, it was demonstrated that the bench-scale sATS system was successful to enable cultivation of U. ohnoi by seeding, resulting in good quality biomass production and efficient nutrient removal, thus justifying upscale experiments.