Current Biotechnology - Volume 9, Issue 1, 2020

Background: Noxious effects of heavy metal pollution on environment have created an alarming situation for human life and aquatic biota and a consequent want for focus on an effort for remediation, because of its high persistence, non-degradable nature, high toxicity and bioaccumulation tendency. Further, heavy metals cannot be converted into non-toxic forms and can only be transformed into less toxic species. Cement dust includes heavy metals like nickel, cobalt, lead, chromium and many other pollutants unsafe to the biotic surroundings, with unfavorable effects on plants, human and animal fitness and ecosystems. Objectives: In the present work, research objectives were to study heavy metal pollution, with a view to establish the contamination status of soil, from cement dust contaminated soils/sediments from various locations around different cement industrial zones in Satna region. The main purpose of this research was to emphasize on the efforts and requisites towards microbial consortium-enhanced bioremediation of heavy metals by bacteria and then study microbial diversity profile through shotgun metagenomics approach. Methods: For this, the isolation of heavy metal tolerant bacterial strains, biostimulation of native strains of microorganisms (bacterial strains) for heavy metal degradation and evaluation of bioaugmented mediated microbial consortium-enhanced bioremediation potential of selected bacterial strains as individual isolates and/or their consortium at the laboratory scale level and then at a large scale were carried out. Results: Through these efforts, in the future, novel efficient tolerant species and their consortium could be explored which could have great bioremediation potential for the uptake of heavy metals from cement dust contaminated soil/sediments, near areas of cement and other industries in Satna region. This review article confirms the prognostication of bioremediation in Satna region. Conclusion: This small vision and efforts of bioremediation could prove to be a small beneficial step and lead to an overall improvement of the socio-economic condition of the locality of Satna and the nearby region. This could be very beneficial for residential people by creating a healthy environment. Soil metagenomics initiatives might be a useful resource to the scientific community and will provide a much greater understanding of microbial diversity and functions in the soil.

Some species of Lactobacillus (Gram-positive bacilli) are promising probiotics with positive physiological effects on the prevention and treatment of diseases. A critical drawback related to the action of these microorganisms refers to the sustainable viability of the cells at adverse conditions (under storage, packing and at gastrointestinal tract flux) - the high humidity conditions inhibit the prolonged viability of the cells. As a consequence, the encapsulation in oxygen-free or impermeable micro containers represents an additional protective procedure to preserve bioactive living cells, providing targeted release of microorganisms at specific parts of the organism. Herein, this mini-review investigates the alternative encapsulation of Lactobacillus spp. by polymeric electrospun fibers. The use of polymeric solutions as templates for electrospinning procedure may increase not only the stability of Lactobacillus spp. but also provide hydrophobic pockets that protect probiotics against adverse conditions. Besides, the electrospun fibers can control the release of species, favoring the therapeutic benefits of probiotics, increasing the viability and stability of Lactobacillus spp.

Background: L-asparaginase is one of the most widely used chemotherapeutic agents for the treatment of a variety of lymphoproliferative disorders and particularly acute lymphoblastic leukemia. Due to increased applications of L-asparaginase in several industrial fields including food processing and medical fields, its production needs to be increased to several folds. Objectives: The aim was (i) to identify the significant factors which affect L-asparaginase production by Streptomyces fradiae NEAE-82 and (ii) to achieve higher production of L-asparaginase. Methods: Sixteen assigned factors and three dummy factors were screened using Plackett-Burman experimental design to determine the most important factors for the production of L-asparaginase by Streptomyces fradiae NEAE-82. Results: L-asparagine was determined to be the most significant positive independent factor (P-value 0.0092) affecting L-asparaginase production by Streptomyces fradiae NEAE-82 followed by pH and NaCl with significant P-values of 0.0133 and 0.0272; respectively. These factors were further optimized by Box-Behnken experimental design. The optimized fermentation conditions, which resulted in the maximum L-asparagine activity of 53.572 UmL-1 are g/L: dextrose 4, L-asparagine 15, KNO3 2, MgSO4.7H2O 0.5, K2HPO4 1, FeSO4.7H2O 0.02, NaCl 0.2, ZnSO4 0.01 and inoculum size 2 %, v/v for 7 days incubation at temperature 37°C, agitation speed 100 rpm, pH 8.5. Conclusion: A total of 3.41-fold increase in the production of L-asparaginase was achieved in the medium after statistical improvement (53.572 UmL-1) as compared to the unoptimized basal medium used prior to the application of Plackett-Burman (15.704 UmL-1).

Background: Artemisia annua is well known for its anti-malarial bio-active compound artemisinin. Development of elite planting material of A. annua and its agro-technology can fulfill the requirement of Artemisinin-based Combination Therapy (ACT) dosages worldwide. Objectives: To develop an efficient in-vitro propagation protocol for A. annua and assess the field performance of in-vitro propagated plants for their growth and artemisinin yield. Methods: The in-vitro propagation protocol of A. annua was developed using the nodal segment in four steps viz: initiation, multiplication, rooting and hardening. In-vitro propagated plants were transplanted with open-pollinated seed raised plants in an experimental field trial having soil supplementation of Farm Yard Manure (FYM), vermicompost and NPK. Result: Maximum 92% shoots were initiated in Murashige and Skoog medium (MS) with 0.44 μM 6-benzyl aminopurine (BA) and highest 281.33 ± 09.75 micro-shoots/inoculum obtained in MS with 15.54 μM BA. The maximum number of roots was found in MS with 100 mg/L activated charcoal while 78.20% of plants survived in the sand: soil: vermicompost (1:1:1) mixture. The highest dry leaf yield (6.37 t/ha) was observed in in-vitro propagated plants grown with vermicompost, while highest artemisinin content (1.11 ± 0.10) and artemisinin yield (65.05 kg/ha) was found in the in-vitro propagated plants grown with FYM after 120 days of transplantation. Conclusion: This study reports an efficient, cost-effective and rapid in-vitro propagation protocol for A. annua as well as enhanced artemisinin yield through the cultivation of in-vitro propagated plants using organic soil supplement inputs. This would lead to an increase in the production of artemisinin yield and fulfill the demand of Artemisinin-based Combination Therapy (ACT).

Background: Synthetic dyes find usage in multiple industries such as paper, textile, food, plastic and pharmaceutical. On their release in industrial effluent and subsequently into the environment, the majority of them affect aquatic and surrounding non-aquatic life because of toxic properties. Therefore, their proper discharge and economical treatment is a matter of great concern. In this context, many enzymes have been reported to efficiently perform dye degradation. Peroxidase is one such enzyme, which causes dye degradation either by precipitation of chemical structure of aromatic dyes or by opening up their aromatic ring structure. The current paper focuses on the major impacts of industrial dyes on the surrounding environment and on exploring the use of bacterial peroxidases as alternative dye degradation compounds. Methods: A bacterial peroxidase was extracted from Bacillus sp. BTS-P5, a strain isolated from a soil sample. Various process parameters were optimized for optimal degradation of ten major industrially important dyes [Bismark Brown R (BBR), Bromophenol Blue (BB), Rhodamine B (RB), Bismark Brown Y (BBY), Direct Violet 21 (DV), Basic Fuchsin (BF), Coomassie Brilliant Blue (CBBG), Congo Red (CR), Direct Black 154 (DB) and Methylene Blue (MB)] by bacterial peroxidase. Results: Basic Fuchsin showed maximum degradation of about 95% by bacterial peroxidase while the Bromophenol Blue was least degraded (29%). Out of the ten dyes, eight dyes showed degradation over 50%. Conclusion: The findings of this research showed that bacterial peroxidase was efficient in dye degradation and hence it has potential as a potent bio-degrader of industrial dyes effluent and wastewater management.

Background: Literature on ethanol production from Lignocellulo-Starch Biomass (LCSB) containing starch besides cellulose and hemicellulose, is scanty. Fed-Batch Separate Hydrolysis And Fermentation (F-SHF) was earlier found more beneficial than Fed-Batch Simultaneous Saccharification and Fermentation (F-SSF). Objective: The study aimed at modification of the saccharification and fermentation strategies by including a prehydrolysis step prior to the SSF and compared the ethanol yields with co-culture fermentation using hexose-fermenting Saccharomyces cerevisiae and pentose-fermenting Scheffersomyces stipitis. Methods: Fed-batch hybrid-SSF and Fed-Batch Separate Hydrolysis and Co-culture Fermentation (F-SHCF) in improving ethanol yield from Steam (ST) or Dilute Sulfuric Acid (DSA) pretreated LCSBs (peels of root and vegetable crops) were studied. Results: There was a progressive build-up of ethanol during F-HSSF up to 72h and further production up to 120h was negligible, with no difference among pretreatments. Despite very high ethanol production in the initial 24h of fermentation by S.cerevisiae under F-SHCF, the further increase was negligible. A rapid hike in ethanol production was observed when S. stipitis was also supplemented because of xylose conversion to ethanol. Conclusion: While ST gave higher ethanol (296-323 ml/kg) than DSA under F-HSSF, the latter was advantageous under F-SHCF for certain residues. Prehydrolysis (24h; 50°C) enhanced initial sugar levels favouring fast fermentation and subsequent saccharification and fermentation occurred concurrently at 37°C for 120h, thus leading to energy saving and hence F-HSSF was advantageous. Owing to the low hemicellulose content in LCSBs, the relative advantage of co-culture fermentation over monoculture fermentation was not significant.