Monitoring and evaluation of childhood stunting reduction program based on fish supplement product in North Sumatera, Indonesia.

The government of Serdang Bedagai Regency initiated a supplementation program to reduce the high prevalence of stunting in the area by delivering extra supplementation, which were nutritious biscuits from national government and fish-based supplement produced from local resources. A 6-month study from April 2022 to September 2022 was conducted to monitor and evaluate the government program that involved 219 under-5-year-old children with height-for-age Z-score (HAZ-score) below - 2. We observed the stunting prevalence reduction by 37.00%, where 81 children recovered from stunting (HAZ-score ≥ - 2). Furthermore, the mean HAZ-score and WHZ-score (Weight-for-Height Z-score) were monitored to significantly improve by 0.97 ± 1.45 (P-value = 1.74e-14) and 1.00 ± 2.18 (P-value = and 2.40e-8), subsequently. The most significant improvement in HAZ-score was monitored among children receiving fish-based supplements with 1.04 ± 1.44 improvement (P-value = 6.59e-17). Then, a significant WHZ-score improvement was reported from children consuming fish-based supplements and a combination of fish-based supplements with nutritious biscuits (P-value = 2.32e-8 and 5.48e-5) by 1.04 ± 2.29 and 0.83 ± 1.84, respectively. The results of the observation become evidence that the program could effectively reduce the prevalence of stunting in children below five years old, especially among children who received locally produced fish-based supplements.

Exploring an l-arabinose isomerase from cryophile bacteria Arthrobacter psychrolactophilus B7 for d-tagatose production.

A novel l-arabinose isomerase (L-AI) from Arthrobacter psychrolactophilus (Ap L-AI) was successfully cloned and characterized. The enzyme catalyzes the isomerization of d-galactose into a rare sugar d-tagatose. The recombinant Ap L-AI had an approximate molecular weight of about 258 kDa, suggesting it was an aggregate of five 58 kDa monomers and became the first record as a homo-pentamer L-AI. The catalytic efficiency (kcat/Km) and Km for d-galactose were 0.32 mM-1 min-1 and 51.43 mM, respectively, while for l-arabinose, were 0.64 mM-1 min-1 and 23.41 mM, respectively. It had the highest activity at pH 7.0-7.5 and 60 °C in the presence of 0.250 mM Mn2+. Ap L-AI was discovered to be an outstanding thermostable enzyme that only lost its half-life value at 60 °C for >1000 min. These findings suggest that l-arabinose isomerase from Arthrobacter psychrolactophilus is a promising candidate for d-tagatose mass-production due to its industrially competitive temperature.

Expression and characterization of thermostable D-allulose 3-epimerase from Arthrobacter psychrolactophilus (Ap DAEase) with potential catalytic activity for bioconversion of D-allulose from d-fructose.

A novel D-allulose 3-epimerase (DAEase) from Arthrobacter psychrolactophilus (Ap DAEase) was first characterized in this study. The enzyme catalyzes the epimerization of d-fructose into a functional rare sugar, D-allulose. Ap DAEase was the first record of DAEase identified as a homotrimer with the molecular weight of its subunit at approximately 34 kDa. It had an optimum activity at pH 8.5 and 70 °C in the presence of 1 mM Mg2+. Ap DAEase was found to be an excellent thermostable enzyme. The half-life value at 70 °C was 128.4 min. The kcat and catalytic efficiency of the enzyme toward d-fructose were 2920.00 s-1 and 3.953 mM-1 s-1, respectively. To the best of our knowledge, Ap DAEase possesses the highest kcat among the previously reported DAEases. The conversion ratio of 500 and 100 mg L-1d-fructose to D-allulose was approximately 27 % in 15 and 90 min, respectively. These research findings suggest that Ap DAEase is a promising candidate for the industrial production of D-allulose.