Limited information is available that seed biopriming with plant growth-promoting Enterobacter spp. play a prominent role to enhance vegetative growth of plants. Contrary to Enterobacter cloacae, Enterobacter hormaechei is a less-studied counterpart despite its vast potential in plant growth-promotion mainly through the inorganic phosphorus (P) and potassium (K) solubilization abilities. To this end, 18 locally isolated bacterial pure cultures were screened and three strains showed high P- and K-solubilizing capabilities. Light microscopy, biochemical tests and 16S rRNA gene sequencing revealed that strains 15a1 and 40a were closely related to Enterobacter hormaechei while strain 38 was closely related to Enterobacter cloacae (Accession number: MN294583; MN294585; MN294584). All Enterobacter spp. shared common plant growth-promoting traits, namely nitrogen (N2) fixation, indole-3-acetic acid production and siderophore production. The strains 38 and 40a were able to produce gibberellic acid, while only strain 38 was able to secrete exopolysaccharide on agar. Under in vitro germination assay of okra (Abelmoschus esculentus) seeds, Enterobacter spp. significantly improved overall germination parameters and vigor index (19.6%) of seedlings. The efficacy of root colonization of Enterobacter spp. on the pre-treated seedling root tips was confirmed using Scanning Electron Microscopy (SEM). The pot experiment of bioprimed seeds of okra seedling showed significant improvement of the plant growth (> 28%) which corresponded to the increase of P and K uptakes (> 89%) as compared to the uninoculated control plants. The leaf surface area and the SPAD chlorophyll index of bioprimed plants were increased by up to 29% and 9% respectively. This report revealed that the under-explored species of P- and K-solubilizing Enterobacter hormaechei sp. with multiple plant beneficial traits presents a great potential sustainable approach for enhancement of soil fertility and P and K uptakes of plants.
The extraction of soluble hydrolysate protein and sugar from a biomass cocktail of defatted soybean meal (DSM) and jackfruit peel (JP) was examined using microwave-alkaline hydrolysis by varying the NaOH concentrations (0.04-0.11 M) and residence times (2-11 min). Based on the central composite design, the optimized parameters were achieved at 0.084 M NaOH concentration (100 mL), for 8.7 min at 300 W microwave power level to obtain the highest protein (5.31 mg/mL) and sugar concentrations (8.07 mg/mL) with > 75% recovery. Both raw and detoxified hydrolysate (using activated carbon) were correspondingly biocompatible with Enterobacter hormaechei strain 40a (P > 0.05) resulting in maximal cell counts of > 10 log CFU/mL. The optimized hydrolysate was prepared as an additive in molasses-alginate bead encapsulation of strain 40a. Further evaluation on phosphate and potassium solubilization performance of the encapsulated strain 40a exhibited comparable results with those of free cell counterpart (P > 0.05). The DSM-JP hydrolysate cocktail holds potential as a carrier additive of encapsulated-cell bead biofertilizers in order to sustain bacterial cell quality and consequently improve crop growth and productivity.
Mimosa pudica Linn is a well-known perennial herb and is traditionally used in ayurvedic medicine for the treatment of various illnesses. Despite its abundance in nature, the therapeutic potential of this invasive weed is deemed to be underappreciated in Malaysia. Previous studies have found an abundance of bioactive compounds associated with potent antioxidant properties in all parts of the plant. However, the optimum parameters required for the extraction of antioxidant compounds are still unknown. Therefore, the present study aimed to optimize the solvent extraction parameters of M. pudica using response surface methodology to enrich the accumulation of antioxidant compounds in the extracts. The effects of the optimized M. pudica extracts were then evaluated on the cell viability and glucose uptake ability in a 3T3-L1 adipocyte cell line. The highest total phenolic (91.98 mg of gallic acid equivalent per g of the dry extract) and total flavonoid content (606.31 mg of quercetin equivalent per g of the dry extract) were recorded when using 100% ethanol that was five-fold and three-fold higher, respectively, as compared to using 50% ethanol. The extract concentration required to achieve 50% of antioxidant activity (IC50 value) was 42.0 µg/mL using 100% ethanol as compared to 975.03 µg/mL using 50% ethanol. The results indicated that the use of 100% ethanol solvent had the greatest impact on the accumulation of antioxidant compounds in the extract (p < 0.05). Cell viability assay revealed that all extract concentration treatments recorded a viability level of above 50%. Glucose uptake assay using 2-NBDG analog showed that the cells treated with 50 µg/mL extract combined with insulin were five-fold higher than the control group. Given the high antioxidant and antidiabetic properties of this plant, M. pudica can be easily highlighted as a plant subject of interest, which warrants further investigation for nutraceutical prospects.
Aptamers are a group of synthetic single-stranded nucleic acids. They are generated from a random library of single-stranded DNA or RNA by a technology named systematic evolution of ligands by exponential enrichment (SELEX). SELEX is a repetitive process to select and identify suitable aptamers that show high affinity and specificity towards target cells. Great strides have been achieved in the design, construction, and use of aptamers up to this point. However, only a small number of aptamer-based applications have achieved widespread commercial and clinical acceptance. Additionally, finding more effective ways to acquire aptamers with high affinity remains a challenge. Therefore, it is crucial to thoroughly examine the existing dearth and advancement in aptamer-related technologies. This review focuses on aptamers that are generated by SELEX to detect pathogenic microorganisms and mammalian cells, as well as in cell-internalizing SELEX for diagnostic and therapeutic purposes. The development of novel aptamer-based biosensors using optical and electrical methods for microbial detection is reported. The applications and limitations of aptamers are also discussed.
The human microbiome has emerged as a key player in maintaining skin health, and dysbiosis has been linked to various skin disorders. Amidst growing concerns regarding the side effects of antibiotic treatments, the potential of live biotherapeutic products (LBPs) in restoring a healthy microbiome has garnered significant attention. This review aims to evaluate the current state of the art of the genetically or metabolically engineered LBPs, termed single-cell engineered LBPs (eLBPs), for skin repair and disease treatment. While some studies demonstrate promising outcomes, the translation of eLBPs into clinical applications remains a significant hurdle. Substantial concerns arise regarding the practical implementation and scalability of eLBPs, despite the evident potential they hold in targeting specific cells and delivering therapeutic agents. This review underscores the need for further research, robust clinical trials, and the exploration of current advances in eLBP-based bioengineered bacterial chassis and new outlooks to substantiate the viability and effectiveness of eLBPs as a transformative approach in skin repair and disease intervention.
Food waste (FW) minimization at the source by using food waste biodigester (FWBs) has a vast potential to lower down the impact of increasing organic fraction in municipal solid waste generation. To this end, this research sought to check the performance of locally isolated hydrolase-producing bacteria (HPB) to improve food waste biodegradation rate. Two under-explored HPB identified as Bacillus paralicheniformis GRA2 and Bacillus velezensis TAP5 were able to produce maximum amylase, cellulase, protease and lipase activities, and demonstrated a significant hydrolase synergy in co-culture fermentation. In vitro biodegradation analysis of both autoclaved and non-autoclaved FW revealed that the HPB inoculation was effective to degrade total solids (>62%), protein (>19%), total fat (>51), total sugar (>86%), reducing sugar (>38%) and starch (>50%) after 8-day incubation. All co-culture treatments were recorded superior to the respective monocultures and the uninoculated control. The results of FW biodegradation using batch-biodigester trial indicated that the 1500 mL and 1000 mL inoculum size of HPB inoculant reached a plateau on the 4th day, with gross biodegradation percentage (GBP) of >85% as compared to control (66.4%). The 1000 mL inoculum was sufficient to achieve the maximum GBP (>90%) of FW after an 8-day biodigestion in a FWB.