Studies on the Influence of Mixed Culture from Buried Soil Sample for Biodegradation of Sago Starch Filled Natural Rubber Latex Gloves

Abstract

The addition of sago starch into natural rubber (NR) latex compounds was aimed to accelerate the degradation process of the end products including gloves as an alternative to reduce solid waste disposal problem. In this research work, the degradation of sago starch filled natural rubber (SS/NR) latex gloves by a mixed culture from buried soil sample was investigated. The Gram staining test of mixed culture showed the Gram-negative bacteria are the dominant species as an effective bacterium to degrade the SS/NR latex gloves. The starch hydrolysis test was performed to confirm the existence of starch-degrading bacteria in mixed culture that consume sago starch from the gloves. Based on the biodegradation rate results obtained, the existence of starch-degrading bacteria together with rubber-degrading bacteria were observed, which accelerate the biodegradation of SS/NR latex gloves by 53.68%. Meanwhile, the biodegradation rate for sago starch unfilled natural rubber (control) latex gloves were only 50.31%. Thus, the addition of sago starch has shown an increased in the biodegradation rate, which can be used as alternative method to overcome the solid waste disposal problem.

Microbial Degradation of Rubber: Actinobacteria

“…Recently, the use of monoculture, co-culture and consortium in rubber degradation studies, mimicking the natural environmental condition, has been compared [ 55 , 64 , 72 , 73 , 142 , 143 ]. The degradation of complex molecules is achieved through co-operative degradation where one organism transforms the original material into products that can be utilized by the other organisms [ 55 , 144 ]. The synergetic interaction of several strains of microorganisms in rubber degradation activity was better when compared to individual strains.…”

Performance-Enhancing Materials in Medical Gloves

“…The global demand for rubber gloves keeps increasing despite the environmental problems related to their disposal [34]. Rubber gloves account for 24% of total medical solid waste [35]. Discarded NR gloves typically take at least two years to degrade in a natural environment.…”

“…In recent years, the widespread usage of rubber and the resulting large amount of waste of this material has increased interest in this field, with the objective of applying bioremediation. NR can be degraded by bacteria and fungi, but the process is slow and even slower in gloves with higher crosslinking densities [35,43]. Linos et al (2000) found that Pseudomonas aeruginosa AL98, a type of Gram-negative bacterium, was capable of disintegrating NR, in its natural form as NR latex concentrates or in its crosslinked forms as NR or IR gloves [44].…”

“…Figure 10 shows a clear zone in the iodine test on an agar plate that proved the starch hydrolyzation. Based on the biodegradation rate data, the presence of starch-degrading microorganisms as well as rubber-degrading bacteria was detected, which accelerated the biodegradation of sago-filled NR gloves by 53.68%, while the biodegradation rate for NR gloves (without filler) was lower, at around 50.31% [35].…”

Smart Materials in Medical Gloves

“…In recent years, the widespread usage of rubber and the resulting large amount of waste of this material has increased interest in this field with the objective of applying bioremediation. NR can be degraded by bacteria and fungi, but the process is slow and even slower in gloves with higher crosslink densities [35,43]. Linos et al, (2000) found that Pseudomonas aeruginosa AL98, gram-negative bacteria, was capable of disintegrating NR, either in its raw form as NR latex concentrates or in its vulcanized forms as NR or IR gloves [44].…”