scholarly journals Nutritional and Volatile Characterisation of Milk Inoculated with Thermo-Tolerant Lactobacillus bulgaricus through Adaptive Laboratory Evolution

Foods ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 2944
Author(s):  
Jiahui Liang ◽  
Michelle Ji Yeon Yoo ◽  
Brent Seale ◽  
Gianpaolo Grazioli
Keyword(s):  
Free Amino ◽  
Gradual Increase ◽  
Lactic Acid Production ◽  
Frozen Storage ◽  
Lactobacillus Bulgaricus ◽  
Adaptive Laboratory Evolution ◽  
Laboratory Evolution ◽  
Volatile Analysis ◽  
Water Holding ◽  
Made In

In this study, thermo-tolerant strain of Lactobacillus bulgaricus (L. bulgaricus) was developed using gradual increase in temperature to induce Adaptive Laboratory Evolution (ALE). Viable colony count of 1.87 ± 0.98 log cfu/mL was achieved at 52 °C, using MRS agar supplemented with 2% lactose. Changes in bacteria morphology were discovered, from rod (control) to filament (52 °C) to cocci after frozen storage (−80 °C). When milk was inoculated with thermo-tolerant L. bulgaricus, lactic acid production was absent, leaving pH at 6.84 ± 0.13. This has caused weakening of the protein network, resulting in high whey separation and lower water-holding capacity (37.1 ± 0.35%) compared to the control (98.10 ± 0.60%). Significantly higher proteolytic activity was observed through free amino acids analysis by LC-MS. Arginine and methionine (237.24 ± 5.94 and 98.83 ± 1.78 µg/100 g, respectively) were found to be 115- and 275-fold higher than the control, contributing to changing the aroma similar to cheese. Further volatile analysis through SPME-GC-MS has confirmed significant increase in cheese-aroma volatiles compared to the control, with increase in diacetyl formation. Further work on DNA profiling, metabolomics and peptidomics will help to answer mechanisms behind the observed changes made in the study.

scholarly journals Engineering improved ethylene production: Leveraging systems Biology and adaptive laboratory evolution

2021 ◽  
Author(s):  
Sophie Vaud ◽  
Nicole Pearcy ◽  
Marko Hanževački ◽  
Alexander M.W. Van Hagen ◽  
Salah Abdelrazig ◽  
...  
Keyword(s):  
Systems Biology ◽  
Ethylene Production ◽  
Adaptive Laboratory Evolution ◽  
Laboratory Evolution

scholarly journals Adaptive Laboratory Evolution of Cupriavidus necator H16 for Carbon Co-Utilization with Glycerol

2019 ◽  
Vol 20 (22) ◽  
pp. 5737 ◽  
Author(s):  
Miriam González-Villanueva ◽  
Hemanshi Galaiya ◽  
Paul Staniland ◽  
Jessica Staniland ◽  
Ian Savill ◽  
...  
Keyword(s):  
Type Strain ◽  
Wild Type Strain ◽  
Carbon Sources ◽  
Strain Engineering ◽  
Cupriavidus Necator ◽  
Superior Performance ◽  
Wild Type ◽  
Adaptive Laboratory Evolution ◽  
Laboratory Evolution ◽  
Cupriavidus Necator H16

Cupriavidus necator H16 is a non-pathogenic Gram-negative betaproteobacterium that can utilize a broad range of renewable heterotrophic resources to produce chemicals ranging from polyhydroxybutyrate (biopolymer) to alcohols, alkanes, and alkenes. However, C. necator H16 utilizes carbon sources to different efficiency, for example its growth in glycerol is 11.4 times slower than a favorable substrate like gluconate. This work used adaptive laboratory evolution to enhance the glycerol assimilation in C. necator H16 and identified a variant (v6C6) that can co-utilize gluconate and glycerol. The v6C6 variant has a specific growth rate in glycerol 9.5 times faster than the wild-type strain and grows faster in mixed gluconate–glycerol carbon sources compared to gluconate alone. It also accumulated more PHB when cultivated in glycerol medium compared to gluconate medium while the inverse is true for the wild-type strain. Through genome sequencing and expression studies, glycerol kinase was identified as the key enzyme for its improved glycerol utilization. The superior performance of v6C6 in assimilating pure glycerol was extended to crude glycerol (sweetwater) from an industrial fat splitting process. These results highlight the robustness of adaptive laboratory evolution for strain engineering and the versatility and potential of C. necator H16 for industrial waste glycerol valorization.

scholarly journals ALEdb 1.0: a database of mutations from adaptive laboratory evolution experimentation

2018 ◽  
Vol 47 (D1) ◽  
pp. D1164-D1171 ◽  
Author(s):  
Patrick V Phaneuf ◽  
Dennis Gosting ◽  
Bernhard O Palsson ◽  
Adam M Feist
Keyword(s):  
Adaptive Laboratory Evolution ◽  
Laboratory Evolution

scholarly journals Banana Pseudo-Stem Increases the Water-Holding Capacity of Minced Pork Batter and the Oxidative Stability of Pork Patties

Foods ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2173
Author(s):  
Diego E. Carballo ◽  
Irma Caro ◽  
Cristina Gallego ◽  
Ana Rebeca González ◽  
Francisco Javier Giráldez ◽  
...  
Keyword(s):  
Oxidative Stability ◽  
Frozen Storage ◽  
Meat Products ◽  
Thiobarbituric Acid ◽  
Sodium Ascorbate ◽  
Thiobarbituric Acid Reactive Substances ◽  
Pork Patties ◽  
Minced Meat ◽  
Water Holding ◽  
Tbars Formation

Banana pseudo-stem (BPS), which is rich in fibre and polyphenols, is a potential functional ingredient for the food industry. In this study, BPS was added at concentrations of 1.5, 3.0, and 4.5 g/kg to a minced pork batter to evaluate its performance as a filler and to pork burger patties to evaluate its performance as a natural antioxidant. The effects of BPS were compared with those of carrageenan and ascorbate, which are a conventional binder and antioxidant, respectively. The performance of BPS was similar to that of carrageenan in terms of the cooking yield and texture of the cooked batter. BPS reduced the brightness of fresh patties and appeared to reduce oxidative discolouration during the frozen storage of raw patties. Moreover, BPS reduced the levels of thiobarbituric acid reactive substances (TBARS) during the refrigerated and frozen storage of cooked patties. A greater decrease in TBARS formation was observed with 4.5 g BPS/kg compared with 0.5 g sodium ascorbate/kg during refrigerated storage. In contrast to ascorbate, BPS promoted the presence of lipid-derived volatile compounds induced by thermal breakdown in the headspace of cooked patties. Nonetheless, this effect was reduced as the amount of BPS in the patties increased. In cooked minced meat products, BPS could increase cooking yields and lipid oxidative stability during storage and might result in a more intense flavour.

Sign in / Sign up

Export Citation Format

Share Document