Effect of Coconut Water Storage Time and Inoculum Size of Lentilactobacillus parafarraginis on Dried Bacterial Cellulose Properties

Abstract

Meanwhile, alternative nitrogen sources are yeast extract, peptone, and corn steep liquor. 10,11 Recently, industrial and agricultural waste, e.g., coconut water, molasses, spoiled fruit cultures, fermentation liquid waste, and orange juice, have been used as nutrient sources in bacterial cellulose synthesis. [12][13][14][15][16] Substituting nutrients substantially decreases the production cost of bacterial cellulose and reduces environmental damage caused by improper handling of industrial waste. In this study, coconut water was used as the main component of the fermentation medium due to its rich mineral content and high levels of fructose (32.52±0.227 -39.04±0.824 mg/mL), glucose (29.96±0.243 -35.43±0.510 mg/mL), and sucrose (6.36±0.06 -0.85±0.010 mg/mL). 17 These sugars were considered the best carbon sources to produce bacterial cellulose. 18 The utilization of coconut water as a fermentation medium yielded a higher dry weight of bacterial cellulose than a combination of Hestrin-Schramm medium and coconut water. 19 In addition to its abundant and affordable availability, coconut water requires no pre-treatment before the fermentation process, making it efficient and cost-effective. 17 Unfortunately, coconut water quality was altered during storage due to the fermentation process by natural microorganisms, such as L. paracasei, L. plantarum, and Pediococcus sp. 20 This resulted in an increase of lactic acid bacteria and a reduction of the pH of coconut water. 21 Furthermore, the natural fermentation process altered the composition of coconut water, mainly sugar, the optimum carbon source for microbial growth. 22 The first documentation of cellulose synthesis by microbes was released in 1886 when Brown identified Acetobacter xylinum as having the ability to synthesize cellulose. 23,24 It is now recognized that several microorganisms, e.g., Gram-positive bacteria, Gram-negative bacteria, and fungi, including yeast-like fungi, are capable of producing the polymer. Another bacterium potentially producing bacterial cellulose is Lentilactobacillus parafarraginis, previously known as Lactobacillus parafarraginis. The phenotypic characterization of L. parafarraginis strain A1 (KU495926) showed that it is a Gram-positive bacterium, a non-motile rod-shaped bacterium, with a length ranging from