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Vine shoots are lignocellulosic agricultural residues. In addition to being an interesting source of polyphenols, they can be used as fillers in a poly(3-hydroxybutyrate-3-hydroxyvalerate) (PHBV) matrix to decrease the overall cost and to propose an alternative to non-biodegradable fossil-based materials. The objective of the present work was to investigate how the incorporation of vine shoots fillers and a preliminary polyphenol extraction step could impact the biodegradability of biocomposites. Biocomposites (20 wt %) were produced by microcompounding. The biodegradation of materials was assessed by respirometric tests in soil. The negative impact of polyphenols on the biodegradability of vine shoots was confirmed. This was supported by crystallinity measurements and scanning electron microscopy (SEM) observations, which showed no difference in structure nor morphology between virgin and exhausted vine shoots particles. The incorporation of vine shoots fillers in PHBV slightly accelerated the overall biodegradation kinetics. All the biocomposites produced were considered fully biodegradable according to the French and European standard NF EN 17033, allowing the conclusion that up-cycling vine shoots for the production of lignocellulosic fillers is a promising strategy to provide biodegradable materials in natural conditions. Moreover, in a biorefinery context, polyphenol extraction from vine shoots has the advantage of improving their biodegradability.Biodegradable plastics have raised great interest, especially for packaging and agriculture sectors, which usually have short-term and single use applications. Polyhydroxyalkanoates (PHA) are a class of polyesters that are synthesized by bacteria grown on carbon sources, stemming from renewable resources and even organic residues. Up to now, the global production of PHAs has represented 3.2% of all the biopolymers after starch blends, polylactic acid (PLA), and polybutylene adipate terephthalate (PBAT) [5]. They are attracting attention from both academia and industry due to their full biodegradability in natural conditions, even in marine conditions, and the possibility of synthetizing a large range of copolymers with different properties. Among PHAs, poly(3-hydroxybutyrate-3-hydroxyvalerate) (PHBV) is a short-chain length copolymer, which is deeply studied and already available on the market. Depending on its hydroxyvalerate (HV) content, mechanical properties are close to those of common polyolefins, with interesting oxygen and water vapor transfer properties, which makes it a good candidate for packaging applications [6]. The biodegradation behavior of PHBV at laboratory scale has been well investigated [7,8]. It can be degraded readily in natural conditions (soil [9], marine waters [10]), producing monomers that are further metabolized [11]. The biodegradation of PHAs happens by the breakage of the ester from the end of the chain. PHAs are fully biodegradable in natural conditions, whereas PLA is only biodegradable in industrial conditions. Poly(3-hydroxybuty...

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