Biosynthesis and characterization of polyhydroxyalkanoates in the polysaccharide-degrading marine bacterium Saccharophagus degradans ATCC 43961

Abstract

The marine bacterium Saccharophagus degradans was investigated for the synthesis of polyhydroxyalkanoates (PHAs), using glucose as the sole source of carbon in a two-step batch culture. In the first step the microorganism grew under nutrient balanced conditions; in the second step the cells were cultivated under limitation of nitrogen source. The biopolymer accumulated in S. degradans cells was detected by Nile red staining and FT-IR analysis. From GC-MS analysis, it was found that this strain produced a homopolymer of 3-hydroxybutyric acid. The cellular polymer concentration, its molecular mass, glass transition temperature, melting point and heat of fusion were 17.2+/-2.7% of dry cell weight, 54.2+/-0.6 kDa, 37.4+/-6.0 degrees C, 165.6+/-5.5 degrees C and 59.6+/-2.2 J g(-1), respectively. This work is the first report determining the capacity of S. degradans to synthesize PHAs.

Formation of Polyhydroxyalkanoate in Aerobic Anoxygenic Phototrophic Bacteria and Its Relationship to Carbon Source and Light Availability

“…Since they have the advantage of being cultivated easily for massive production, bacteria are the main targeted organisms for this purpose (10). In recent years, many marine bacteria have been reported to be able to produce PHAs (2,13,29,30,35). Some bacteria have been employed as sewerage scavengers (4).…”

Enhanced Agarose and Xylan Degradation for Production of Polyhydroxyalkanoates by Co-Culture of Marine Bacterium, Saccharophagus degradans and Its Contaminant, Bacillus cereus

“…The production of PHA by Sde 2-40 was reported to start at exponential growth phase and PHA accumulation of 0.58 g/L at 20 h and 0.53 g/L at 24 h were obtained using 20 g/L glucose and starch in marine broth, respectively [14]. The PHA production exponentially increased after carbon source feeding until fed-batch end and reached 21.3% of dry cell weight (2.71 g/L) using glucose and 17.4% of dry cell weight (2.04 g/L) using starch in marine broth during the fermentation period of 49 h [13]. Alva Munoz and Riley [12] reported PHA production by Sde 2-40 up to 1.5 g/L from 4% glucose in marine sea salt minimal media.…”

“…The PHA contents from agarose and xylan were 18.1% and 34.5% of dry cell weight in one step culture and 13.6% and 30.2% of dry cell weight in two step culture, respectively. Marine bacterium Sde 2-40 is well known for the production of PHA using glucose [13] and starch [14]. The production of PHA by Sde 2-40 was reported to start at exponential growth phase and PHA accumulation of 0.58 g/L at 20 h and 0.53 g/L at 24 h were obtained using 20 g/L glucose and starch in marine broth, respectively [14].…”

“…Sde 2-40 can produce PHB homopolymer using glucose Appl. Sci. 2017, 7, 225 2 of 16 and starch as carbon sources in marine sea salt minimal media [12][13][14]. Recently, research interest has been growing in the bacterial cumulative process for the production of PHA using complex polysaccharides [15,16].…”

Polyhydroxybutyrate as Bio-Degradable Plastic – A Review

“…Synthetic plastics remain in the environment for long time as they are resistant to degradation (4). Bioplastics are made from variety of sources like polysaccharides, lipids and also proteins (5). A few examples of protein used as substrates for bioplastic production are soy protein, wheat gluten, zein, rice and egg albumin.…”