Recent Patents on Biotechnology - Volume 18, Issue 1, 2024

The last few decades have seen a rise in the number of deaths caused by neurological disorders. The blood-brain barrier (BBB), which is very complex and has multiple mechanisms, makes drug delivery to the brain challenging for many scientists. Lipid nanoparticles (LNPs) such as nanoemulsions, solid-lipid nanoparticles, liposomes, and nano lipid carriers (NLCs) exhibit enhanced bioavailability and flexibility among these nanocarriers. NLCs are found to be very effective. In the last few decades, they have been a center of attraction for controlled drug delivery. According to the current global status of specific neurological disorders, out of all LNPs, NLC significantly reduces the cross-permeability of drugs through the BBB due to their peculiar properties. They offer a host of advantages over other carriers because of their biocompatibility, safety, non-toxicity, non-irritating behavior, stability, high encapsulation efficiency, high drug loading, high drug targeting, control of drug release, and ease in manufacturing. The biocompatible lipid matrix is ideally suited as a drug carrier system due to the nano-size range. For certain neurological conditions such as Parkinsonism, Alzheimer's, Epilepsy, Multiple sclerosis, and Brain cancer, we examined recent advances in NLCs to improve brain targeting of bioactive with special attention to formulation aspects and pharmacokinetic characteristics. This article also provides a brief overview of a critical approach for brain targeting, i.e., direct nose-to-brain drug delivery and some recent patents published on NLC128;.

Light energy directly affects microalgae growth and productivity. Microalgae in natural environments receive light through solar fluxes, and their duration and distribution are highly variable over time. Consequently, microalgae must adjust their photosynthetic processes to avoid photo limitation and photoinhibition and maximize yield. Considering these circumstances, adjusting light capture through artificial lighting in the main culture systems benefits microalgae growth and induces the production of commercially important compounds. In this sense, this review provides a comprehensive study of the role of light in microalgae biotechnology. For this, we present the main fundamentals and reactions of metabolism and metabolic alternatives to regulate photosynthetic conversion in microalgae cells. Light conversions based on natural and artificial systems are compared, mainly demonstrating the impact of solar radiation on natural systems and lighting devices, spectral compositions, periodic modulations, and light fluxes when using artificial lighting systems. The most commonly used photobioreactor design and performance are shown herein, in addition to a more detailed discussion of light-dependent approaches in these photobioreactors. In addition, we present the principal advances in photobioreactor projects, focusing on lighting, through a patent-based analysis to map technological trends. Lastly, sustainability and economic issues in commercializing microalgae products were presented.

Background: Cancer is among the leading causes of death worldwide, imposing high costs on the health systems of all societies. Extensive biological studies are required to discover appropriate therapies. Escherichia coli has long been regarded as one of the main biotechnological bio-factories to produce recombinant protein-based therapeutics. In the present study, five strains of E. coli were compared to achieve the maximum production of a previously designed recombinant immunotoxin-carrying MAP30 toxin against VEGF-overexpressed cancer cells in a benchtop bioreactor.Methods: The recombinant immunotoxin coding gene sequence was extracted from the NCBI database. The host used to produce the recombinant immunotoxin were five E. coli strains of BL21 (DE3), DH5α, SHuffle^®T7, XL1-Blue, and Rosetta-gami^TM (DE3). CaCl2 method was used for bacterial transformation. Bacterial growth measurements were performed using optical density measurements at 600 nm. The immunotoxin production was measured using SDS-PAGE analysis. The best-producing strain was cultivated in a 10-L benchtop stirred tank bioreactor. Recent patents on this field were also studied.Results: The results demonstrated that the BL21 (DE3) strain had the highest expression of recombinant protein in comparison to other strains. Moreover, the cell growth of E. coli BL21 (DE3) and SHuffle^®T7 strains before transformation in the LB medium, were significantly higher in comparison to other strains. Additionally, the transformation of Rosettagami was associated with decreased cell proliferation. The transformation of the XL1-Blue strain did not effect cell growth. Analysis of the growth kinetics demonstrated appropriate proliferation of the transformed BL21 (DE3) cells in the laboratory benchtop bioreactor.Conclusions: Based on the results of this study, the BL21 (DE3) strain could be used as a suitable host for the production of the recombinant immunotoxin against VEGF in stirred tank bioreactor, which can be employed for the treatment of tumors. Yet, its precise mechanism must be explored in extensive studies.

Background: Citrus cultivar improvement via conventional breeding strategies is impeded by factors related to its reproductive biology. The orange is a hybrid between pomelo (Citrus maxima) and mandarin (Citrus reticulata). Among various orange cultivars, Valencia oranges have a bit of bitter tang mixed in with their sweetness, as Navel oranges are, the most widely cultivated citrus species, quite sweeter, and also don't contain any seeds. Tangelo mandarin orange cultivar is a hybrid of C. reticulata æ#151; C. maxima or æ#151; C. paradisi.Objective: The present study was undertaken to optimize the hormonal composition of the media with regard to plant growth regulators for in vitro propagation of sweet orange cultivars from nodal segment explants.Methods: The nodal segment explants were collected from three citrus cultivars, Washington Navel, Valencia and Tangelo. Murashige and Skoog (MS) medium supplemented with sucrose and different concentrations of growth regulators was used for shoot proliferation and root induction, and the optimum medium composition was assessed. The patent for Citrus Tissue Culture was obtained from the Office of Research Affairs, Haramaya University.Results: The results indicate that the highest shoot response was recorded for Washington's navel with maximum shoot proliferation rate (99.75%), shoot number per explant (1.76), shoot length (10.70 cm), leaf number per explants (3.54) after three weeks of culture. In all experiments, no growth was observed for the basal MS medium. Phytohormone combinations of IAA (1.2 mg/L) and kinetin (2.0 mg/L) were found to be the best for shoot proliferation. Among the cultivars, there were significant differences for the highest rooting rate (81.255), root number (2.22), and root length (2.95 cm) variables for Washington Navel. The lowest rooting rate (48.45%), root number (1.47) and root length (2.26 cm) were observed for Valencia. The highest rooting rate (84.90%), root number per microshoot (2.22) and root length (3.05 cm) was on MS medium supplemented with 1.5 mg/L NAA.Conclusion: A comparison of different concentrations of IAA and NAA on root induction of microshoots from nodal segments of citrus cultivars demonstrated NAA was a more effective hormone than IAA.

Introduction: Moloney Murine Leukemia Virus Reverse Transcriptase (MMLV RT) is a common enzyme used to convert RNA sequences into cDNA. However, it still has its shortcomings, especially in terms of processivity and thermostability. According to a previous patent, the fusion of polymerase enzyme to an archaeal DNA-binding protein has been proven to enhance its performance. Furthermore, recent studies have also stated that the fusion of a polymerase enzyme to an archaeal DNA-binding protein is predicted to improve its thermostability and processivity.Aim: As an early stage of enzyme development, this study aimed to design, express, and purify enzymatically active MMLV RT fused with archaeal DNA-binding protein.Methods: RT fusion proteins were designed and evaluated using in silico methods. The RT fusion enzyme was then expressed in Escherichia coli BL21(DE3) and purified. Its reverse transcriptional activity was proved using reverse transcription quantitative polymerase chain reaction (RT-qPCR).Results: This study showed that MMLV RT fusion with Sis7a protein at its C-terminal end using commercial linker (GGVDMI) produced the best in silico evaluation results. The RT fusion was successfully expressed and purified. It was also known that the optimal condition for expression of the RT fusion was using 0.5 mM IPTG with post-induction incubation at room temperature (± 26°C) for 16 hours. In addition, the activity assay proved that the RT fusion has the reverse transcriptional activity.Conclusion: This study shows that the designed MMLV RT Sis7a fusion can be expressed and purified, is enzymatically active, and has the potential to be developed as an improved RT enzyme. Further study is still needed to prove its thermostability and processivity, and further characterize, and plan production scale-up of the MMLV RT Sis7a fusion for commercial use.

Background: The pituitary glands normally produce and stores gonadotropic hormones (GnH) that are responsible for ovulation and spermiation in animals. However, whether fish pituitary extracts can elicit same effects in treated animals need elucidation as a prelude to their practical usage in animals.Objectives: The aim of this study was to investigate the oestrus-inducing potential of the pituitary gland extract of the Africa Catfish (Clarias gariepinus) in immature Wistar rats.Methods: The experiment involved the use of 18 immature female Wistar rats and 10 male catfish brood stocks with the use of six Wistar rats per groups as follows: Group A had human chorionic gonadotropin (hCG) treatment. Group B had only normal saline treatment as the control whereas Group C had the C. gariepinus pituitary extract administration to induce oestrus with treatments occurring twice six hours apart in each group.Results: There was an obvious expression of visible signs of heat and the presence of uterine horn oedema with significant (p < 0.05) increase in reproductive tract weight and uterine width and length. However, only progesterone levels increased significantly (p < 0.05) in the hCG and the C. gariepinus pituitary extract treated groups compared to other assayed hormones.Conclusion: These results showed that C. gariepinus pituitary extract has the capacity to induce oestrus in Wistar rats because of its gonadotropic effects, which needs further investigations at higher doses and for longer exposure periods for possible oestrus induction and synchronization in higher mammals. Further favourable results could herald the possible patent of the catfish pituitary extract for either experimental or commercial use in mammals.