Low-value By-products Research Articles

Effects of solid-state fermentation on the phytochemical composition and antioxidant activities of oriental mustard ( Brassica juncea) and yellow mustard ( Sinapis alba) bran

Mustard bran is enriched with bioactive phenolic compounds and glucosinolates, yet it is underutilized as a low-value processing by-product. Here, we investigate the effects of solid-state fermentation (SSF) using various food-grade microorganisms (Aspergillus spp., Rhizopus spp., Bacillus subtilis, Saccharomyces cerevisiae) on the phytochemical composition and antioxidant activities of oriental mustard and yellow mustard brans. The total phenolic contents (TPC) and antioxidant activities (FRAP, DPPH assays) of oriental and yellow mustard brans were significantly improved (p < 0.05) after fermentation, especially by R. oligosporus and R. oryzae. Moreover, SSF by R. oligosporus and R. oryzae significantly increased (p < 0.05) the levels of p-hydroxybenzoic acid, syringic acid, protocatechuic acid, sinapic acid and kaempferol-3-O-glucoside in both mustard brans. Conversely, a significant reduction (p < 0.05) of major glucosinolates in oriental and yellow mustard brans were observed after SSF by R. oligosporus. Findings from this study show that SSF by filamentous fungi is a promising strategy to enhance the phenolic contents, antioxidant properties and overall value of oriental and yellow mustard brans.

Pilot-scale extraction of multiple biopesticidal compounds from mustard biofuel by-products

Oils from Sinapis alba and Brassica juncea mustards can be used as a raw material for biofuel and biodiesel. Mustard seed meal left after oil extraction is considered a low value by-product. Valorization of mustard meal into biopesticide is one of the promising directions. The development of a suitable pilot scale extraction and concentration procedure is the first critical step to achieve this goal. Thus, the objective of the presented work was to develop a scaled-up process for producing mustard seed meal biopesticides. Modular pilot plant was built to allow for up to 100 gallons extraction capacity. The pilot plant setup included components that are widely accessible and can be adjusted to meet a range of production scales. The ratio of mustard seed meal to water, temperature, and extraction times were optimized for extraction of major mustard biopesticidal compounds (ionic thiocyanate, 4-hydroxybenzyl alcohol, and sinigrin). To evaluate the potential as an animal feed and further valorization of mustard seed meal, extracted mustard seed meals were analyzed for chemical composition. Based on total digestible nutrients and net energies, both B. juncea and S. alba extracted mustard seed meals were siutable animal feed for dairy cows.

Applications and Properties of Hemp Stalk-Based Insulating Biomaterials for Buildings: Review.

There has been increasing interest in green and recyclable materials to promote the circular economy. Moreover, the climate change of the last decades has led to an increase in the range of temperatures and energy consumption, which entails more energy expenditure for heating and cooling buildings. In this review, the properties of hemp stalk as an insulating material are analyzed to obtain recyclable materials with green solutions to reduce energy consumption and reduce noise to increase the comfort of buildings. Hemp stalks are a low-value by-product of hemp crops; however, they are a lightweight material with a high insulating property. This study aims to summarize the research progress in materials based on hemp stalks and to study the properties and characteristics of the different vegetable binders that could be used to produce a bio-insulating material. The material itself and its microstructural and physical aspects that affect the insulating properties are discussed, as is their influence on durability, moisture resistance, and fungi growth. Research suggests using lignin-based or recyclable cardboard fiber to develop a bio-composite material from hemp stalk, but long-term stability requires further investigation.

Use of a fully biobased and non-reprotoxic epoxy polymer and woven hemp fabric to prepare environmentally friendly composite materials with excellent physical properties

In the future, materials will need to be biobased and produced sustainably without compromising mechanical properties. To date, in many cases, the advantages of the bio-origin of the raw material are overridden by the environmental impact of the process. In the present study, we have developed a novel composite material based on woven hemp fabric which reinforce a thermoset polymer produced from birch bark, a low-value forestry byproduct. Results show that this fully biobased composite has specific stiffness and strength equivalent to those of flax fibre-reinforced petroleum-based epoxy composites and slightly lower than glass fibre-reinforced petroleum-based epoxy composites. The sustainability of the material was also evaluated by life-cycle assessment from cradle to gate and showed significantly superior performance with respect to the potential global warming impact than commercial benchmark materials. Furthermore, toxicology studies showed no endocrine disruptive activities. This is an important proof of concept study demonstrating that biobased structural materials can be produced sustainably.

Highly efficient synthesis of benzyl benzoate directly from self-coupling of benzyl alcohol in water

Benzyl benzoate (BB), an important ester, still demands for green synthesis routes. In this work, by size regulation and proper functionalization of carbon nanotubes (CNTs) as the support of gold catalyst, this ester can be synthesized very efficiently directly from benzyl alcohol via oxidative coupling. More attractively, the reaction is performed using water as green solvent and molecular oxygen as green oxidant. Simultaneously, very high selectivity to BB can be obtained near full conversion within very short reaction time (just 0.5 h), while the low-value benzoic acid byproduct is negligible. This is very different from many reported gold catalysts that yield much benzoic acid and/or benzaldehyde in water. The results show that, besides the size of CNTs (length and diameter), the functionalization of CNTs is also critical for improving both conversion and the selectivity to BB. In addition, the reaction mechanism for forming BB ester is put forward as well.

Fish By-Products: A Source of Enzymes to Generate Circular Bioactive Hydrolysates.

Fish viscera are usually discarded as waste, causing environmental problems, or as low-value by-products. This study describes a self-sufficient and zero waste approach to obtain enzymes and protein hydrolysates from fish by-products. Firstly, recovery steps of viscera enzymatic extract were applied, and the resulting raw extract was stable at a pH range of 8-9 and at temperatures between 40 and 50 °C. The application of the extracted enzymes and alcalase on fish by-products hydrolysis was also determined. The selected conditions for the enzymatic hydrolysis were 10% (E/S) for 6 h using viscera enzymatic extract and 3% (E/S) for 2 h using alcalase. Fish protein hydrolysates (FPH) proved to have a notable antioxidant capacity with similar activity, ~11 mg ascorbic acid/g dry extract (ABTS assay) and ~150 mg Trolox/g dry extract (ORAC assay). FPH were also able to inhibit the angiotensin-converting enzyme, however, alcalase hydrolysates revealed a higher antihypertensive potential, IC50 of 101 µg of protein/mL. In general, FPH obtained by both enzymes systems maintained these bioactivities after the passage throughout a simulated gastrointestinal tract. The hydrolysates also displayed important technological properties, namely oil absorption capacity (~1 g oil/g sample) and emulsifying property (~40%). Therefore, it will be conceivable to use fish by-products based on a circular economy approach to generate added value compounds for animal and human nutrition.

Separation of neodymium from FeNd alloy and the preparation of porous iron alloy by chemical dealloying in molten chlorides: Application to the recovery of NdFeB wastes

Neodymium-iron-boron (NdFeB) magnets are the rare earth products with the largest output, and their recycling is of significance for the sustainable development of rare earth resources. Currently, the recycling technology of NdFeB wastes is more concerned with the recovery of rare-earth elements, while iron is regarded as a low-value by-product. In this work, chemical dealloying method in molten chlorides was proposed to separate neodymium from FeNd alloy and simultaneously to prepare porous iron alloy. The effects of the molar ratio of reactants, dealloying temperature and time on the separation efficiency of neodymium were investigated. The maximum separation efficiency of neodymium from FeNd alloy can reach 96 %. The separation process of neodymium and the formation process of porous iron alloy were estimated based on the ICP, XRD, XPS, SEM-EDS analyses of recycled products. Neodymium was separated from FeNd alloy by the reaction with Nd(III) ions to form Nd(II) ions in molten chlorides, while the porous iron alloy was formed. The formed Nd(II) ions can be transformed into Nd(III) ions and metallic neodymium particles by the disproportionation reaction. In the process, Nd(III) ions can act as a complement to react with FeNd alloy. And neodymium was recovered in the form of metallic neodymium and NdOCl from the chloride melt and the rinsing solution of porous iron alloy, respectively. The formed porous iron alloy had the surface area of unit volume in the range of (2 ∼ 20) × 104 cm2 cm−3, the pore width around 10 nm and good hardness. The porous iron alloy is a high value-added product.

INVESTIGATION OF THE EFFECT OF WALNUT SHELL PROCESSING METHODS ON THE RELEASE OF ANTIOXIDANT SUBSTANCES

The article presents the results of studies of the effect of processing methods on the output of antioxidant substances from walnut shells. Technological processes and modes of extract production are substantiated. At the same time, the size of the crushed shell, the extraction time and the concentration of the solvent were investigated. Most of the nuts are shells and husks, low-value by-products rich in phenolic compounds. At the same time, the shell obtained at the stage of cleaning the cores, as a rule, is usually disposed of by incineration. Whereas such an organization of production is possible, in which the shell will be concentrated and processed for the release of valuable biologically active substances, on the basis of which new domestic drugs of various therapeutic and preventive actions can be developed. Phenolic compounds extracted from walnut shells are potentially good natural sources of antioxidants for the food industry and have numerous health benefits. Walnuts have a greater antioxidant capacity than any other nut, since the shell is mainly composed of lignin, a strong source of phenols. Studies show that lignin characterizes the strength level of the shell, and by its chemical composition is a source of antioxidants. Because of this special quality, it is very important to split and loosen the dense structure so that the solvent penetrates the cell to extract phenolic compounds. Thus, in order to obtain a higher yield of phenolic compounds, the correct method of isolating antioxidant substances is crucial.

Antioxidant, Anti-Diabetic, Anti-Obesity, and Antihypertensive Properties of Protein Hydrolysate and Peptide Fractions from Black Sesame Cake.

A low-value by-product of cold-pressed sesame oil is defatted black sesame cake (DBSC). The remaining protein and essential amino acids may be utilized as a renewable biological source to produce bioactive products. The bioactivities of the protein hydrolysate from black sesame cake and its peptide fractions were examined in this study for in vitro antioxidant activity and inhibition of DPP-IV, ACE, α-amylase, α-glucosidase, and pancreatic lipase. By using Flavourzyme to hydrolyze DBSC, followed by ultrafiltration, fractions with peptide sizes of <3, 3−10, and >10 kDa were obtained. According to the findings, the products of DBSC could neutralize free radicals and prevent ferric ion redox reactions. The highest inhibitory effects were shown with low Mw peptides (<3 kDa) against ACE, DPP-IV, α-amylase, and α-glucosidase. DBSC has demonstrated potential as a nutraceutical or functional ingredient for preventing and treating disorders associated with free radicals, such as diabetes, hypertension, and hyperglycemia.

Sustainable Synthesis of Silicon Precursors Coupled with Hydrogen Delivery Based on Circular Economy via Molecular Cobalt-Based Catalysts.

The development of a circular economy is a key target to reduce our dependence on fossil fuels and create more sustainable processes. Concerning hydrogen as an energy vector, the use of liquid organic hydrogen carriers is a promising strategy, but most of them present limitations for hydrogen release, such as harsh reaction conditions, poor recyclability, and low-value byproducts. Herein, we present a novel sustainable methodology to produce value-added silicon precursors and concomitant hydrogen via dehydrogenative coupling by using an air- and water-stable cobalt-based catalyst synthesized from cheap and commercially available starting materials. This methodology is applied to the one-pot synthesis of a wide range of alkoxy-substituted silanes using different hydrosilanes and terminal alkenes as reactants in alcohols as green solvents under mild reaction conditions (room temperature and 0.1 mol % cobalt loading). We also demonstrate that the selectivity toward hydrosilylation/hydroalkoxysilylation can be fully controlled by varying the alcohol/water ratio. This implies the development of a circular approach for hydrosilylation/hydroalkoxysilylation reactions, which is unprecedented in this research field up to date. Kinetic and in situ spectroscopic studies (electron paramagnetic resonance, nuclear magnetic resonance, and electrospray ionization mass spectrometry), together with density functional theory simulations, further provide a detailed mechanistic picture of the dehydrogenative coupling and subsequent hydrosilylation. Finally, we illustrate the application of our catalytic system in the synthesis of an industrially relevant polymer precursor coupled with the production of green hydrogen on demand.

Microwave-Assisted Extraction of Bioactive Compounds from Lentil Wastes: Antioxidant Activity Evaluation and Metabolomic Characterization.

The recovery of industrial by-products is part of the zero-waste circular economy. Lentil seed coats are generally considered to be a waste by-product. However, this low-value by-product is rich in bioactive compounds and may be considered an eco-friendly source of health-promoting phytochemicals. For the first time, a sustainable microwave-assisted extraction technique was applied, and a solvent screening was carried out to enhance the bioactive compound content and the antioxidant activity of green and red lentil hull extracts. With respect to green lentil hull extracts that were obtained with different solvents, the aqueous extract of the red lentil seed coats showed the highest total phenolic and total flavonoid content (TPC = 28.3 ± 0.1 mg GAE/g dry weight, TFC = 1.89 ± 0.01 mg CE/100 mg dry weight, respectively), as well as the highest antioxidant activity, both in terms of the free radical scavenging activity (ABTS, 39.06 ± 0.73 mg TE/g dry weight; DPPH, IC50 = 0.39 μg/mL) and the protection of the neuroblastoma cell line (SH-SY5Y, IC50 = 10.1 ± 0.6 μg/mL), the latter of which has never been investigated so far. Furthermore, a metabolite discovery analysis was for the first time performed on the aqueous extracts of both cultivars using an HPLC separation which was coupled with an Orbitrap-based high-Resolution Mass Spectrometry technique.

Determining the performance of lignin-based flocculants in improving biosludge dewaterability

In the wastewater treatment plant of pulp and paper mills, biosludge dewatering is needed to reduce the sludge handling and disposal costs. It is usually facilitated by means of the addition of synthetic polymers. There is increasing interest in replacing synthetic polymers with biopolymers derived from low value by-products or industrial residuals to improve the environmental footprint of dewatering. In this study, lignin-based flocculants (LBF) were tested for their ability to improve the biosludge dewaterability based on Capillary Suction Time (CST) and dry cake solids achieved with a Crown Press. The results demonstrate that LBFs alone can significantly enhance dewatering with a decrease in CSTs from 72.7 ± 5.1 s (unconditioned biosludge) to 23.3 ± 0.4 s and an increase in dry cake solids after pressing from 7.1 ± 0.5% to 13.9 ± 1.3% with a relatively high dosage of 7.5% w/w. However, with dual conditioning a LBF and 0.1% w/w anionic polyacrylamide (APAM), the required dosage of LBF was reduced to 3% w/w to achieve a dry cake solids content of 13.8 ± 0.4%, the same as that achieved with Zetag8165, a commercial synthetic polymer. LBF addition lowered the particle surface charge, allowing the particles to agglomerate and enhancing for the biosludge dewaterability. The application of LBFs for sludge dewatering offers novel considerable promise for providing more sustainable approaches by optimizing the use of lignin from different extraction processes, applying various types of lignin modifications in combination with anionic polymers, and exploring different methods of disposal or utilization of the dewatered sludge.

Lithium extraction from β-spodumene: A comparison of keatite and analcime processes

The conventional processing of β-spodumene involves decrepitation at about 1100 °C, digestion with concentrated sulfuric acid at 250 °C, and several purification stages that identify the process with high energy, feedstock, and by-product intensity. In addition to the low-value by-product of sodium sulfate (Na2SO4), the disposal cost of another by-product, hydrogen aluminosilicate (HAlSi2O6, aka keatite-HAlSi2O6), drives the research to avoid its formation in lithium refineries or converting this material into marketable products such as zeolites. Two processes are developed to leach lithium from β-spodumene in a single digestion step using solutions of NaCl, with and without the addition of NaOH, operating at up to 200 °C. The optimised processes extract at least 92.9% of Li by varying the leaching time, temperature, liquid to solid mass ratio, NaCl/β-spodumene mass ratio, solution pH and agitation. The two processes are simple, prevent using concentrated sulfuric acid and preclude forming HAlSi2O6 and Na2SO4 by-products, resulting in significantly lower amounts of impurities in the leach liquor, and high selectivity for lithium extraction. The keatite process functions at circumneutral pH, high NaCl/β-spodumene and L/S ratios and generates sodium aluminosilicate (keatite-NaAlSi2O6) as a by-product. The analcime process requires alkaline pH to produce analcime (NaAlSi2O6·H2O) as a by-product. The study demonstrates a shift in the mechanism between circumneutral and alkaline conditions from ion exchange to dissolution-precipitation (i.e., recrystallisation). In an analogy to keatite and analcime processes for NaCl, we also investigate the extraction of lithium from β-spodumene with KCl with and without KOH but find both reactions to be ineffective in recovering Li. The analcime process offers a cleaner and less hazardous alternative to the conventional sulfuric acid process while maintaining a high lithium extraction effectiveness, rapid reaction rates and high concentration of Li in the leach.

A novel approach for accelerating smear development on bacterial smear-ripened cheeses reduces ripening time and inhibits the growth of Listeria and other unwanted microorganisms on the rind

Bacterial smear-ripened cheeses are commonly contaminated with fungi and the potentially dangerous pathogen Listeria monocytogenes, which compromises food safety and quality. Here, we present new approach for accelerating smear development on these cheeses, while reducing growth of unwanted microorganisms. We grew the smear microorganism Brevibacterium linens in acid whey (AW) supplemented with a by-product of whey protein hydrolysate production (FCH). B. linens grew to a high cell density (10.27 log 10 CFU/mL), and alkalized the AW-FCH medium. We found that the fermented AW-FCH, with its high pH, rapidly killed L. monocytogenes and yeasts. When culture medium was smeared on the cheese surface, the surface pH was rapidly neutralized, and in just 7 days, the cheeses developed a dense orange color and growth of spoilage fungi was inhibited. Summing up, by growing B. linens to high cell density on low-value dairy byproducts, and applying dense suspensions onto cheeses, we can reduce the time needed for establishing the smear. Added benefits are increased food safety and less spoilage, as quick smear development inhibits growth of unwanted microorganisms on the rind. Preliminary tests at a dairy show that flavor development is comparable to traditional bacterial surface-ripened cheeses with far more complex surface microflora.

Physical, Chemical and Biochemical Modification Approaches of Potato (Peel) Constituents for Bio-Based Food Packaging Concepts: A Review.

Potatoes are grown in large quantities and are mainly used as food or animal feed. Potato processing generates a large amount of side streams, which are currently low value by-products of the potato processing industry. The utilization of the potato peel side stream and other potato residues is also becoming increasingly important from a sustainability point of view. Individual constituents of potato peel or complete potato tubers can for instance be used for application in other products such as bio-based food packaging. Prior using constituents for specific applications, their properties and characteristics need to be known and understood. This article extensively reviews the scientific literature about physical, chemical, and biochemical modification of potato constituents. Besides short explanations about the modification techniques, extensive summaries of the results from scientific articles are outlined focusing on the main constituents of potatoes, namely potato starch and potato protein. The effects of the different modification techniques are qualitatively interpreted in tables to obtain a condensed overview about the influence of different modification techniques on the potato constituents. Overall, this article provides an up-to-date and comprehensive overview of the possibilities and implications of modifying potato components for potential further valorization in, e.g., bio-based food packaging.

Obtaining and characterization of olive (Olea europaeaL.) pomace flour: An investigation on its applicability in gluten‐free cake formulations added with xanthan

Olive pomace (OP) is a recognized cheap and abundant source of nutrients and gelling material. This study explored for the first time a total substitution of wheat flour by a mix of pulp-enriched flour derived from OP (OPF) with corn flour (CF) and/or rice flour (RF) for obtaining gluten-free (GF) cakes. OPF markedly increased lipid (9.37%–9.85%) and fiber (1.82%–3.16%) contents of GF cakes, which showed to have bioactivity in terms of total phenolic content (12.5–19.5 mg GAE/g) and antiradical activity (62.3%–90.1%). Xanthan gum (XG) addition (0.25% w/w) to GF cakes improved crumb structure, color, and helped to reduce crumb hardiness. A simplex centroid mixture design indicated interactions between OPF, CF, and RF affecting the firmness of GF cakes (1.97–7.48 N). Overall, F2 and F3 led to the best formulations with OPF, as this highly valuable and functional ingredient when associated with XG technologically improved GF cake formulations. Novelty impact statement The pomace obtained from olive oil extraction processing, a low commercial value by-product was freeze-dried and incorporated into gluten-free cake formulations as flour (OPF) to partially replace corn and rice flours. The performance of OPF with and without hydrocolloid (xanthan gum) was assessed, resulting in a highly nutritive, with pleasant appearance and acceptable texture cakes. This investigation highlights the potential application of bioactive-rich OPF as an alternative ingredient for incorporation in foods destined for celiac patients.

How Cerium and Lanthanum as Coproducts Promote Stable Rare Earth Production and New Alloys.

The largest outputs of rare earth mining are the low-value byproducts cerium and lanthanum, which burden rare earth supply chains because they must be separated from more desirable rare earths used in magnet production. Promoting demand for cerium and lanthanum can potentially diversify the economics of rare earth mining and improve supply chain stability for all rare earth elements. A promising avenue for increasing byproduct rare earth element demand is their use in aluminum alloys; an application for cerium and lanthanum offering multiple benefits to manufacturing such as energy reduction and improved throughput. Experimental materials science and economic implications of Al-rare earth element alloys will be discussed. We show that Al–La/Ce alloys have elevated mechanical strength compared to more traditional aluminum alloys, in some formulations can be used without heat treatment, and possess a highly castable eutectic microstructure. This report presents the use of cerium and lanthanum in aluminum alloys as an example of how supply chain focused approaches to technological development can benefit stakeholders at every step in production.Graphical

Effects of Blending Tobacco Lignin with HDPE on Thermal and Mechanical Properties.

Depletion of fossil fuels and the detrimental environmental impacts of synthetic plastics have prompted a global interest in bio-based polymers. Lignin is an abundant, unused, and low-value byproduct of pulping and biochemical operations that has the potential to decrease the need for plastics derived from petroleum. Melt blending is one of the easiest strategies for expanding the commercial applications of lignin. Concerns remain, however, regarding the negative effects of lignin on the final composite material’s performance, and the increase in manufacturing costs. This study investigates the effects of blending lignin extracted from tobacco using a novel one-step processing technique on injection molding parameters, and the mechanical, physical, and thermal properties of high-density polyethylene (HDPE). By extruding HDPE pellets and lignin powder, varying blend concentrations (0, 5, 10, 15, and 30% wt.) were produced. Scanning electron microscopy (SEM) and optical microscopy were used to investigate the compatibility of the blend morphology. Results indicated that interfacial interactions were achieved as particles of tobacco lignin were well dispersed and uniformly distributed throughout HDPE. Intermolecular interactions between HDPE and lignin were also discovered through Fourier-transform infrared (FTIR) spectral analyses. The tensile test results showed that increase in lignin content up to 15% wt. had little effect on tensile strength, but at 30% wt., a 19% reduction was observed. With the addition of 5, 10, 15, and 30% wt. of lignin, the tensile modulus increased by 4%, 29%, 25%, and 8%, respectively. TGA results demonstrated that at 15% and 30% wt., tobacco lignin acted as a thermal stabilizer. The processability study revealed that tobacco lignin could be processed easily using injection molding without requiring significant changes to the process parameters. Overall, tobacco lignin showed great promise as a biodegradable HDPE filler.

Physiological changes in Rhodococcus ruber S103 immobilized on biobooms using low-cost media enhance stress tolerance and crude oil-degrading activity

For economic feasibility, sugarcane molasses (0.5%, w/v) containing K2HPO4 (0.26%, w/v) and mature coconut water, low value byproducts, were used in cultivation of Rhodococcus ruber S103 for inoculum production and immobilization, respectively. Physiological changes of S103 grown in low-cost media, including cell hydrophobicity, saturated/unsaturated ratio of cellular fatty acids and biofilm formation activity, enhanced stress tolerance and crude oil biodegradation in freshwater and even under high salinity (5%, w/v). Biobooms comprised of S103 immobilized on polyurethane foam (PUF) was achieved with high biomass content (1010 colony-forming units g−1 PUF) via a scale-up process in a 5-L modified fluidized-bed bioreactor within 3 days. In a 500-L mesocosm, natural freshwater was spiked with crude oil (72 g or 667 mg g−1 dry biobooms), and a simulated wave was applied. Biobooms could remove 100% of crude oil within only 3 days and simultaneously biodegraded 60% of the adsorbed oil after 7 days when compared to boom control with indigenous bacteria. In addition, biobooms had a long shelf-life (at least 100 days) with high biodegradation activity (85.2 ± 2.3%) after storage in 10% (w/v) skimmed milk at room temperature. This study demonstrates that the low-cost production of biobooms has potential for future commercial bioremediation.

Uniformly Dispersed Poly(lactic acid)-Grafted Lignin Nanoparticles Enhance Antioxidant Activity and UV-Barrier Properties of Poly(lactic acid) Packaging Films.

Poly(lactic acid) (PLA) represents one of the most widely used biodegradable polymers for food packaging applications. While this material provides many advantages, it is characterized by limited antioxidant and UV-barrier properties. Blending PLA with lignin is an attractive strategy to address these limitations. Lignin possesses antioxidant properties and absorbs UV-light and is a widely available low value byproduct of the paper and pulp industry. This study has explored the use of lignin nanoparticles to augment the properties of PLA-based films. A central challenge in the preparation of PLA–lignin nanoparticle blend films is to avoid nanoparticle aggregation, which could compromise optical properties as well as antioxidant activity, among others. To avoid nanoparticle aggregation in the PLA matrix, PLA-grafted lignin nanoparticles were prepared via organocatalyzed lactide ring-opening polymerization. In contrast to lignin and unmodified lignin nanoparticles, these PLA-grafted lignin nanoparticles could be uniformly dispersed in PLA for lignin contents up to 10 wt %. The addition of as little as the equivalent of 1 wt % of lignin of these nanoparticles effectively blocked transmission of 280 nm UV-light. At the same time, these blend films retained reasonable visible light transmittance. The optical properties of the PLA lignin blend films also benefited from the well-dispersed nature of the PLA-grafted nanoparticles, as evidenced by significantly higher visible light transmittance of blends of PLA and PLA-grafted nanoparticles, as compared to blends prepared from PLA with lignin or unmodified lignin nanoparticles. Finally, blending PLA with PLA-grafted lignin nanoparticles greatly augments the antioxidant activity of these films.