Spent Coffee Waste as a Potential Media Component for Xylanase Production and Potential Application in Juice Enrichment

Abstract

In this study, spent coffee waste (SCW) was used as the sole carbon source for xylanase production in solid state fermentation mode using Aspergillus niger. A Box–Behnken design was constructed using three parameters viz. temperature, initial moisture content, and log number of spores to determine the optimal fermentation condition. The best fermentation conditions for xylanase production were found to be incubation at 30 °C with an initial moisture content of 70% and using an inoculum of 6.5 × 106 spores/g of dry SCW. Furthermore, the design of experiments revealed that maintaining a medium composition of 0.2 g of yeast extract, 0.04 g of K2HPO4, and 0.03 g of MgSO4 increased xylanase production. Under optimised solid-state fermentation conditions an enzyme activity of 6495.6 IU/g of dry SCW was recorded, which was approximately 1.39-fold higher than that of control (4649 IU/g of dry SCW). The efficacy of the purified xylanase as a juice enrichment agent for strawberry, blueberry, and raspberry pulp was tested.

Bioprocess development for production of a process-apt xylanase with multifaceted application potential for a range of industrial processes

“…A xylanase produced from Aspergillus niger was purified, and investigated for its fruit juice clarification potential of various fruits like strawberry, blueberry, and raspberry pulp [23]. Similar to the current study, enzyme dosage, temperature and time of enzyme treatment, were earmarked as the most vital variables which influenced the clarification of fruit juices.…”

“…SSF was executed for xylanase production by cultivating Aspergillus niger on spent coffee waste as the sole carbon source. Various process parameters were optimized using a Box-Behnken design to achieve 1.39-fold increased xylanase yield [23]. Similarly, spent mushroom substrate of Pleurotus florida was employed as the substrate for SSF based production of lignocellulolytic enzymes such as cellulases and xylanases using species of Trichoderma and Aspergillus [21].…”

“…Optimization of variables like wheat bran, incubation time, pH, and CaCl 2 using response surface methodology resulted in 1.92-fold increased xylanase yield from A. terreus S9 under SmF [28]. Similarly, process variables like temperature, initial moisture content, and inoculum (log number of spores), were optimized using a Box-Behnken design for xylanase production from Aspergillus niger under SSF on spent coffee waste to achieve 1.39-fold increased yield [23].…”

“…Ahmed et al [3] reported xylanase mediated clarification of orange juice (64%) after 72 h, while Elegbede and Lateef [11] documented higher level of clarification (74.22%) after 24 h. Similarly, Adiguzel et al [2] reported that treatment of different fruit juices (orange, pomegranate, apricot, peach, apple, grape, and kiwi) with Pediococcus acidilactici GC25 xylanase improved the clarification, increased the reducing sugar amount, and decreased the turbidity. Xylanase produced from Aspergillus niger under optimized SSF conditions on spent coffee waste, was purified and examined for its efficacy for clarification/enrichment of various fruit juices like strawberry, blueberry, and raspberry [23].…”

Enhancing crystallization, miscibility, and processability of bio‐based polybutylene succinate/polypropylene blended composites via coffee husk reinforcement

“…Coffee husk (CH) is a coffee waste with interlinked complex molecular structure of lignocellulose materials like cellulose, hemicellulose, and lignin. [30][31][32] Recently, sustainable PBS biocomposites have been fabricated using spent coffee waste as a renewable source to lower the cost of production. Results also showed that such composites can degrade twice as fast and exhibit higher stiffness than neat PBS.…”