Sustainable Polyhydroxyalkanoate Production from Food Waste via Bacillus mycoides ICRI89: Enhanced 3D Printing with Poly (Methyl Methacrylate) Blend.

In view of implementing green technologies for bioplastic turning polices, novel durable feedstock for Bacillus mycoides ICRI89 used for efficient polyhydroxybutyrate (PHB) generation is proposed herein. First, two food waste (FW) pretreatment methods were compared, where the ultrasonication approach for 7 min was effective in easing the following enzymatic action. After treatment with a mixture of cellulase/amylases, an impressive 25.3 ± 0.22 g/L of glucose was liberated per 50 g of FW. Furthermore, a notable 2.11 ± 0.06 g/L PHB and 3.56 ± 0.11 g/L cell dry eight (CDW) over 120 h were generated, representing a productivity percentage of 59.3 wt% using 25% FW hydrolysate. The blend of polyhydroxybutyrate/poly (methyl methacrylate) (PHB/PMMA = 1:2) possessed the most satisfactory mechanical properties. For the first time, PHB was chemically crosslinked with PMMA using dicumyl peroxide (DCP), where a concentration of 0.3 wt% had a considerable effect on increasing the mechanical stability of the blend. FTIR analysis confirmed the molecular interaction between PHB and PMMA showing a modest expansion of the C=O stretching vibration at 1725 cm-1. The DCP-PHB/PMMA blend had significant thermal stability and biodegradation profiles comparable to those of the main constituent polymers. More importantly, a 3-Dimetional (3D) filament was successfully extruded with a diameter of 1.75 mm, where no blockages or air bubbles were noticed via SEM. A new PHB/PMMA "key of life" 3D model has been printed with a filling percentage of 60% and a short printing time of 19.2 min. To conclude, high-performance polymeric 3D models have been fabricated to meet the pressing demands for future applications of sustainable polymers.

A comparative study between two carboxymethylated polysaccharides/protein electrostatic and cross-linked nanogels constructed for caffeic acid and eugenol delivery.

In response to the pressing demand for functional nanomaterials synthesis and applications, two polyelectrolyte complexes (PECs) [electrostatic and cross-linked nanogels (NGs)] loaded individually with caffeic acid (CafA) and eugenol (Eug) demonstrating multifunctionalities were proposed for the first time. Curdlan (Curd) and glucomannan (GM) were carboxymethylated (CMCurd and CMGM) successfully and polymeric ratios of 1:1 and 4:1 (v/v) for chitosan (Cs): CMCurd and lactoferrin (Lf): CMGM were selected for the synthesis of Cs/CMCurd and Lf/CMGM NGs. Due to the use of EDC/NHS, Cs/CMCurd/CafA and Lf/CMGM/Eug NGs possessed very uniform particles sizes of 177 ± 18 and 230 ± 17 nm with marked encapsulation efficiencies (EEs) of 76 ± 4 and 88 ± 3 %, respectively. The formation of a carbonyl-amide linkage in both cross-linked NGs was confirmed by FTIR. It should be noted, the self-assembly was not reliable in retaining enough of the encapsulated compounds. Owing to the excellent physicochemical characteristics of the loaded cross-linked NGs, they were prioritized over the electrostatic ones. Both Cs/CMCurd/CafA and Lf/CMGM/Eug NGs exhibited high colloidal stability over 12 weeks, elevated hemocompatibility, and in vitro serum stability. The generated NGs were also tailored to possess controlled release profiles for CafA and Eug over 72 h. Cs/CMCurd/CafA and Lf/CMGM/Eug NGs had promising antioxidant efficacies and could remarkably inhibit 4 bacterial pathogens at low 2-16 µg/mL concentration of encapsulated NGs compared to their unencapsulated counterparts. Interestingly, the respective NGs could significantly decline the IC50 against colorectal cancer HCT-116 than conventional drugs. Based on these data, it was conferred that the investigated NGs could be promising candidates for functional foods and pharmaceutics.

Novel Biodegradable Nanoparticulate Chain-End Functionalized Polyhydroxybutyrate-Caffeic Acid with Multifunctionalities for Active Food Coatings.

The bioactivities of polyhydroxyalkanoates have been curtailed owing to the lack of bioactive functional groups in their backbones. In this regard, polyhydroxybutyrate (PHB) produced from new locally isolated Bacillus nealsonii ICRI16 was chemically modified for enhancing its functionality, stability as well as solubility. First, PHB was transformed to PHB-diethanolamine (PHB-DEA) by transamination. Subsequently, for the first time, the chain ends of the polymer were substituted by caffeic acid molecules (CafA), generating novel PHB-DEA-CafA. The chemical structure of such a polymer was confirmed by Fourier-transform infrared (FTIR) spectroscopy and proton nuclear magnetic resonance (1H NMR). The modified polyester demonstrated improved thermal behavior compared to PHB-DEA as was shown by thermogravimetric analysis, derivative thermogravimetry, and differential scanning calorimetry analyses. Interestingly, 65% of PHB-DEA-CafA was biodegraded in a clay soil environment after 60 days at 25 °C, while 50% of PHB was degraded within the same period. On another avenue, PHB-DEA-CafA nanoparticles (NPs) were successfully prepared with an impressive mean particle size of 223 ± 0.12 nm and high colloidal stability. The nanoparticulate polyester had powerful antioxidant capacity with an IC50 of 32.2 mg/mL, which was the result of CafA loading in the polymer chain. More importantly, the NPs had a considerable effect on the bacterial behavior of four food pathogens, inhibiting 98 ± 0.12% of Listeria monocytogenes DSM 19094 after 48 h of exposure. Finally, the raw polish sausage coated with NPs had a significantly lower bacterial count of 2.11 ± 0.21 log cfu/g in comparison to other groups. When all these positive features are recognized, the polyester described herein could be considered as a good candidate for commercial active food coatings.

Sustainable curdlan biosynthesis by Rahnella variigena ICRI91 via alkaline hydrolysis of Musa sapientum peels and its edible, active and modified hydrogel for Quercetin controlled release.

Despite the high demand for curdlan (Curd), its industrial implementation has not reached a mature stage due to the high cost of simple sugar feed stocks. Herein, Musa sapientum peels hydrolysate (MPH) was proposed for the first time as a sustainable medium for Curd generation and as an ameliorated functional biomaterial for quercetin (Quer) sustained release. In this study, banana peels have been hydrolysed by 3 % NaOH catalyst/ 60 °C, yielding high concentration of glucose 20.5 ± 0.04 and 24.3 ± 0.11 g/L and reducing sugar amount, respectively. Meanwhile, a novel local Rahnella variigena ICRI91 strain was isolated from soil, that was useful for Curd production and identified by 16S rRNA analysis. Furthermore, three-batch fermentation models were carried out using MPH for obtaining a sufficient yield of Curd. R. variigena ICRI91 accumulated a satisfactory Curd concentration; 10.3 ± 0.25 g/L; using 60 g/L MPH. On the other hand, the strain produced an impressive Curd yield; 21.5 ± 0.13 g/L with an attained productivity of 0.179 ± 0.01 g/L/h and a sugar consumption of 68 ± 0.25 % as the MPH content increased to 100 g/L. For the first time, Curd hydrogel was modified by different amount of Xylitol (Xyl), reaching good mechanical performance; 3.1 MPa and 75 % for tensile strength (TS) and elongation at break (EB), respectively. Curd/Xyl (3/5) hydrogel was then integrated with nanometer-sized quercetin nanocrystals (Quer NCs, 83 ± 0.12 nm) with high colloidal stability of -23 ± 0.05 mV. The interconnected H- bonding between Xyl and Curd was confirmed by FTIR and SEM. The generated biomaterial was tailored to exhibit a sustained Quer release over 72 h. It also has improved antibacterial efficacy against four bacterial pathogens compared to that of a free drug. In recognition of these merits, an edible polymeric nanomaterial has been proposed for the functional food and biomedicine sectors.

The Hyperproduction of Polyhydroxybutyrate Using Bacillus mycoides ICRI89 through Enzymatic Hydrolysis of Affordable Cardboard.

Bioplastics are contemplated as remarkable substitutes for conventional plastics to accommodate green technological advancements. However, their industrial production has not been fully implemented owing to the cost of carbon resources. From another perspective, valorizing different paper mill wastes has become a prominent research topic. These materials may serve as an affording sustainable feedstock for bioplastic production. Adjustment of cardboard waste hydrolysate as suitable fermentation media for production of bacterial polyhydroxyalkanoates (PHAs) has been investigated. Cardboard samples were defibered and dried before enzymatic hydrolysis. The enzymatic degradation of commercial cellulase was monitored over 15 days. Interestingly, 18.2 ± 0.2 g/L glucose yield was obtained from 50 g cardboard samples using a 1.5% (v/v) enzyme concentration. The samples exhibited maximum weight loss values of 69-73%. Meanwhile, five soil samples were collected from local sites in Lodz, Poland. A total of 31 bacterial isolates were screened and cultured on Nile blue plates. Analysis of the 16S rRNA gene sequence of the most potent producer revealed 100% similarity to Bacillus mycoides. Cardboard hydrolysates whole medium, modified MSM with cardboard hydrolysate and nitrogen depleted MSM with cardboard hydrolysate were utilized for PHA production, followed by PHA productivity and cell dry weight (CDW) estimation compared to glucose as a standard carbon source. An impressive PHA accumulation of 56% CDW was attained when the waste hydrolysate was used as a carbon source. FTIR and NMR analysis of the isolated PHA indicated that functional groups of the polymer were related to PHB (polyhydroxybutyrate). Thermal analysis demonstrates that PHB and PHB-CB (PHB produced from cardboard hydrolysate) have degradation temperatures of 380 and 369 °C, respectively, which reflect the high thermal stability and heat resistance compared to the same properties for a standard polymer. This is the first demonstration of full saccharification of corrugated cardboard paper waste for high-level production of PHA. In addition, the attained PHB productivity is one of the highest levels achieved from a real lignocellulosic waste.

Naturally-Sourced Antibacterial Polymeric Nanomaterials with Special Reference to Modified Polymer Variants.

Despite the recent advancements in treating bacterial infections, antibiotic resistance (AR) is still an emerging issue. However, polymeric nanocarriers have offered unconventional solutions owing to their capability of exposing more functional groups, high encapsulation efficiency (EE) and having sustained delivery. Natural polymeric nanomaterials (NMs) are contemplated one of the most powerful strategies in drug delivery (DD) in terms of their safety, biodegradability with almost no side effects. Every nanostructure is tailored to enhance the system functionality. For example, cost-effective copper NPs could be generated in situ in cellulose sheets, demonstrating powerful antibacterial prospects for food safety sector. Dendrimers also have the capacity for peptide encapsulation, protecting them from proteolytic digestion for prolonged half life span. On the other hand, the demerits of naturally sourced polymers still stand against their capacities in DD. Hence, Post-synthetic modification of natural polymers could play a provital role in yielding new hybrids while retaining their biodegradability, which could be suitable for building novel super structures for DD platforms. This is the first review presenting the contribution of natural polymers in the fabrication of eight polymeric NMs including particulate nanodelivery and nanofabrics with antibacterial and antibiofilm prospects, referring to modified polymer derivatives to explore their full potential for obtaining sustainable DD products.

In vitroassessment of green polyhydroxybutyrate/chitosan blend loaded with kaempferol nanocrystals as a potential dressing for infected wounds.

Despite the major medical advancements in recent decades, treating infected wounds successfully remains a challenge. In this research, a functional blend of Polyhydroxybutyrate (PHB) and Chitosan (Cs) was developed for wound infection mitigation with tailored biological and physicochemical properties. Water insoluble kaempferol (KPF) was pre-formulated to water soluble KPF nanocrystals (KPF-NCs) with fine particle size of 145 ± 11 nm, and high colloidal stability (-31 ± 0.4 mV) to improve its drug transdermal delivery. PHB-Cs-KPF-NCs (1:2 ratio) film owned the best physical properties in terms of high breathability, thermal stability and mechanical strength (33 ± 1 MPa). Besides, XRD and FTIR findings indicated the interaction between Cs, PHB and KPF, reducing the film crystallinity. The scanning electron microscopy of the film displayed a highly interconnected porous morphology. KPF-NCs were integrated in PHB-Cs matrix with a marked encapsulation efficiency of 96.6%. The enhanced drug-loading film showed a sustain release pattern of KPF-NCs over 48 h. Interestingly, the developed blend possessed an impressive blood clotting capacity within 20 min. Furthermore, we presented a new naturally-sourced mixture of Cs+KPF-NCs with powerful antibacterial effects against MDRStaphylococcus aureusandAcentibacter baumanniiat very low concentrations. The membrane evidenced a remarkable antibacterial naturein vitrowith almost 100% cell viability reduction against the study strains after 48 h. By virtue of these advantages, this green blend is highly proposed for optimal wound care.

Polyhydroxyalkanoate nanoparticles produced by marine bacteria cultivated on cost effective Mediterranean algal hydrolysate media.

Algae are omnipresent in all seas and oceans, which make thema target for many applications such as bio-fertilizers, fish feeding and removal of heavy metals. In the present study, different algal species were examined as sustainable alternatives substrates for PHA production by Halomonas sp. Several media simulations were utilized to achieve high polymer productivity. The maximum poly(3-hydroxybutyrate) (PHB) concentrations were determined by using Corallina mediterranea hydrolysates as a carbon and nitrogen source. The isolates Halomonas pacifica ASL10 and Halomonas salifodiane ASL11 were found to be able to produce PHA by 67 % wt and 63 % wt CDW, respectively. PHB nanoparticles (NPs) had high zeta potential values and small particle sizes. These properties make it suitable for several drug delivery and pharmaceutical applications. Interestingly, NPs showed a potent antibacterial activity against several reference strains. The antibacterial efficacy of PHA-NPs has not been previously studied, thus this study opens a promising use of PHA-NPs.

Dual Therapeutic Targeting of Lung Infection and Carcinoma Using Lactoferrin-Based Green Nanomedicine.

In view of the promising applications of nanoparticles in drug delivery, this study highlights the fabrication of new bioactive green protein-polysaccharide nanocomplexes with significant antibacterial and antitumor efficacies. We preformulated the water-insoluble drugs Quercetin (Quer) and Resveratrol (Res) as water-soluble nanocrystals to facilitate their entrapment in the electrostatic lactoferrin-chondroitin (Lf-ChS) nanocomplex. Quer and Res were physically entrapped in the Lf-ChS nanomatrix with high encapsulation efficiencies (EE %) of 85.2 and 90.1% w/w for Quer and Res, respectively. The in vitro synergetic antibacterial effects of the studied compounds against all bacterial strains were confirmed. Res-Quer Lf-ChS NPs revealed an enhanced cytotoxic effect against A549 lung cancer cells. A new model of polymicrobial lung infection was designed, where treatment with Res-Quer Lf-ChS NPs (233.5 ± 6.59 nm) resulted in a marked decline of 3.2 log units in bacterial counts. In the lung tumor model, the potent antitumor efficacy of the developed Res-Quer Lf-ChS NPs was demonstrated by a noticeable decline in both lung weight and the biomarkers compared to the positive control group that did not receive any treatment. In conclusion, the green Res-Quer Lf-ChS NPs possess antibacterial and antitumor attributes for potential lung infection and tumor therapy.

Ribosomal proteins as a possible tool for blocking SARS-COV 2 virus replication for a potential prospective treatment.

Coronavirus disease (COVID-19) is caused by SARS-COV2 and has resulted in more than four million cases globally and the death cases exceeded 300,000. Normally, a range of surviving and propagating host factors must be employed for the completion of the infectious process including RPs. Viral protein biosynthesis involves the interaction of numerous RPs with viral mRNA, proteins which are necessary for viruses replication regulation and infection inside the host cells. Most of these interactions are crucial for virus activation and accumulation. However, only small percentage of these proteins is specifically responsible for host cells protection by triggering the immune pathway against virus. This research proposes RPs extracted from bacillus sp. and yeast as new forum for the advancement of antiviral therapy. Hitherto, antiviral therapy with RPs-involving viral infection has not been widely investigated as critical targets. Also, exploring antiviral strategy based on RPs could be a promising guide for more potential therapeutics.