Bioprospecting microwave-alkaline hydrolysate cocktail of defatted soybean meal and jackfruit peel biomass as carrier additive of molasses-alginate-bead biofertilizer

Abstract

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.

Effect of Microwave Pretreatment on the Antioxidant Activity and Stability of Enzymatic Products from Milk Protein

“…The peptide content was a positive correlation with the DH of MP ( Figure 1 ). These results were similar to that of microwave pretreatment on the chicken feather [ 42 ] and defatted soybean meal [ 43 ].…”

Okra Growth, Yield and Rhizosphere Microbiome Responses to the Encapsulated Bioinoculant Application under Reduced Fertilization Regime

“…Bacterial inoculants have been shown in various studies to have a wide variety of plant-beneficial effects on plant physiology and productivity. In previous research, we found that the P- and K-solubilizing E. hormaechei strain 40a promotes the early vegetative growth of okra seedlings [ 23 , 24 , 43 ]. The purpose of this study was to assess its impact on okra growth and yield, with a focus on soil rhizosphere bacteria to gain insight into the changes that happened within the complex taxonomic systems.…”

“…For free-cell strain 40a, the cell suspensions were collected after centrifugation and adjusted to ~10 log CFU/mL in 0.8% NaCl. For encapsulated strain 40a, a ~10 log CFU/mL culture pellet was suspended after cell washing in 50 mL defatted soybean meal + jackfruit peel (DSM-JP) hydrolysate (pH 6.5–7.0) [ 24 ] and combined with 50 mL of 3% ( w / v ) homogenized sodium alginate solution (sterilized at 121 °C for 15 min). The mixture was then extruded through a silicone tube (internal diameter 3 mm) by using a microtube pump MP-3N (Eyela, Tokyo, Japan) into a sterile 100 mL of 3% ( w / v ) CaCl 2 (premixed with 1.5% molasses) with a delivery rate of 30 beads/min.…”

“…The use of bioinoculants as biofertilizers in agriculture could be made more practical thanks to bacterial encapsulation technology. Encapsulation technology provides a novel method of soil amendment that enhances the use of soil bioinoculant application through the formulation of carriers specifically for their intended uses [ 24 , 25 , 26 ]. In essence, this technology creates a barrier of protection that permits the controlled release of microorganisms and the long-term maintenance of their bioactivity [ 27 ].…”

“…In light of the above conclusions, we aimed to unravel the impacts of strain 40a application on okra grown in 60 days in greenhouse conditions under a different rate of inorganic fertilizers input. To improve bioinoculant survivability in the soil rhizosphere, we encapsulated strain 40a in the molasses-alginate bead enriched with defatted soybean meal + jackfruit peel hydrolysate (DSM-JP) cocktail, as proposed in our prior research [ 24 ]. The effects of application of both free-cell and encapsulated strain 40a on okra growth and yield will be evaluated in this research.…”