# Harnessing Agri-Food Waste as a Source of Biopolymers for Agriculture
## 2 Sources of Biopolymers
### Cellulose: A Resourceful Biopolymer in All Its Forms
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Entry** & **Biomass** & \multicolumn{2}{c}{**Purification Method**} & **Cellulose (\%)** & **Characteristics** & **Ref.** \\ \hline \multirow{2}{*}{1} & Palm (_Arecaceae_ sp.) & Alkaline & H\({}_{2}\)O\({}_{2}\) & N/A & 87.12\% purity, crystallinity of 69.9\% & [75] \\  & leaves & hemicellulose removal & Delignification & & crystallinity of 69.9\% & [75] \\ \hline \multirow{2}{*}{2} & \multirow{2}{*}{Corn (_Zan mays_)} & Hemicululose removal by & Organosolv & \multirow{2}{*}{77} & 90\% enzymatic & \multirow{2}{*}{[25]} \\  & & authodyndlysis & Delignification & & hydolysis yield & \\  & & cobs & Hemicululose removal by & Alkaline & 89.2\% enzymatic & \multirow{2}{*}{[25]} \\  & & authodyndlysis & Delignification & & hydrolysis yield & \\ \hline \multirow{6}{*}{3} & Mature Coconut & \multirow{6}{*}{43} & \multirow{6}{*}{60.76–45.78} & 79.88–80.43\% & \multirow{6}{*}{[76]} \\  & (_Cos nuclei_rea L.) & & & & & CMC yield from \\ \cline{1-1}  & coir & Alkaline & hemicellulose and & & & cellulose \\ \cline{1-1}  & Young Coconut & pretreatment & lignin removal & 1 to 3 times & \multirow{2}{*}{[76]} \\ \cline{1-1}  & (_Cos nuclei_rea L.) & & & & 50.34–40.76 & \multirow{2}{*}{[76]} \\ \cline{1-1}  & coir & & & & & \\ \hline \multirow{2}{*}{4} & Bamboo (_Bambusa_ & \multirow{2}{*}{Ligninolytic enzymes producing fungi (_Paracennium_ & \multirow{2}{*}{N/A} & Selectivity of \multirow{2}{*}{[77]} \\  & _rulgaris_) culls & sp. LCB1 + _Clonostachys compatiuscuula_ LCN1)} & & & \multirow{2}{*}{[78]} \\ \hline \multirow{2}{*}{5} & _Melia dubia_ woody & \multirow{2}{*}{Enzolv method} & \multirow{2}{*}{52} & 20\% increase in crystallinity & [78] \\  & biomass & & & & & crystallinity \\ \hline \hline \end{tabular} N/A: not available.  
\end{table} 
Table 4: Cellulose purification from agri-food waste. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline
**Entry** & **Biomass** & **Pretreatment** & **Microorganism** & \multicolumn{2}{c}{**Yield \% (g**} & \multirow{2}{*}{**Final**} & \multirow{2}{*}{**Ref.**} \\  & & & & & **Cellulose/g** & \\  & & & & & **Biomass)** & \\ \hline \multirow{2}{*}{1} & Orange (_Cirrus \(\times\) sinensis_) & UAE diluted acid & \multirow{2}{*}{
\begin{tabular}{c} _Komagatehiacter_ \\ _sucrofermentans_ \\ DSM 15973 \\ \end{tabular} } & \multirow{2}{*}{5.82} & N/A & [79] \\  & processing waste & & & DSM 15973 & & \\ \hline \multirow{2}{*}{2} & Mango (_Mangifera indica_) & \multirow{2}{*}{Nitric acid hydrolysis} & _Achromobacter_ S3 & N/A & 1.22 & [80] \\  & peel waste & & & & \\ \hline \multirow{2}{*}{3} & Olive (_Olea europaea_) & Mild acid treatment + & _Novacetomonas_ & \multirow{2}{*}{9.60} & \multirow{2}{*}{0.68} & [73] \\  & pomace & enzymatic hydrolysis & _hansenii_ 53582 & & \\ \hline \hline \end{tabular} N/A: not available.  
\end{table} 
Table 5: BC from waste biomass. CMC-PVA (polyvinyl alcohol) blend were able to degrade within two months [86], while those formed with CMC and soybean protein, compared with high density polyethylene (HDPE), led to an increased germination of cabbage seeds [87]. The production of mulch films was also found to be feasible in combination with antimicrobial elements such as silver nanowires for an enhanced crop protection [88].