Genomic Characterization of Mobile Genetic Elements Associated with Multidrug-Resistant Acinetobacter Non-baumannii Species from Southern Thailand.

This study investigated the genetic diversity, antimicrobial resistance profiles, and virulence characteristics of Acinetobacter non-baumannii isolates obtained from four hospitals in southern Thailand. Clinical data, genome information, and average nucleotide identity (ANI) were analyzed for eight isolates, revealing diverse genetic profiles and novel sequence types (STs). Minimum spanning tree analysis indicated potential clonal spread of certain STs across different geographic regions. Antimicrobial resistance genes (ARGs) were detected in all isolates, with a high prevalence of genes conferring resistance to carbapenems, highlighting the challenge of antimicrobial resistance in Acinetobacter spp. infections. Mobile genetic elements (MGEs) carrying ARGs were also identified, emphasizing the role of horizontal gene transfer in spreading resistance. Evaluation of virulence-associated genes revealed a diverse range of virulence factors, including those related to biofilm formation and antibiotic resistance. However, no direct correlation was found between virulence-associated genes in Acinetobacter spp. and specific clinical outcomes, such as infection severity or patient mortality. This complexity suggests that factors beyond gene presence may influence disease progression and outcomes. This study emphasizes the importance of continued surveillance and molecular epidemiological studies to combat the spread of multidrug-resistant (MDR) Acinetobacter non-baumannii strains. The findings provide valuable insights into the epidemiology and genetic characteristics of this bacteria in southern Thailand, with implications for infection control and antimicrobial management efforts.

Evaluation of curcuminoids, physiological adaptation, and growth of Curcuma longa under water deficit and controlled temperature.

Turmeric (Curcuma longa L.; Zingiberaceae), an economically important crop and a major spice in Indian cuisine, produces natural yellow color (curcumin) as well as curcuminoids which are widely utilized in traditional and modern medicinal practices. During the turmeric culture, the fluctuations of precipitation and seasonal changes in the whole life cycle play a major role, especially water shortage and decreasing temperature (in winter season), leading to rhizome dormancy under extreme weather conditions. The objective of this investigation was to understand how the water deficit and reduced temperature affect turmeric growth, physiological adaptation, quantity, and quality of turmeric rhizomes. Four-month-old turmeric plants were subjected to four treatments, namely normal temperature and well-watered (RT-WW), or water-deficit (RT-WD) conditions in the greenhouse, 25 °C controlled temperature and well-watered (CT-WW), or water-deficit (CT-WD) conditions in glasshouse. Leaf osmotic potential considerably declined in 30 days CT-WD treatment, leading to chlorophyll degradation by 26.04%, diminution of maximum quantum yield of PSII (Fv/Fm) by 23.50%, photon yield of PSII (ΦPSII) by 29.01%, and reduction of net photosynthetic rate (Pn) by 89.39% over CT-WW (control). After 30 days water withholding, fresh- and dry-weights of rhizomes of turmeric plants grown under CT-WD declined by 30-50% when compared with RT-WW conditions. Subsequently, curcuminoid content was reduced by 40% over RT-WW plants (control), whereas transcriptional expression levels of curcuminoids-related genes (CURS1, CURS2, CURS3, and DCS) were upregulated in CT-WD conditions. In summary, the water withholding and controlled temperature (constant at 25 °C day/night) negatively affected turmeric plants as abiotic stresses tend to limit overall plant growth performances and curcuminoid yield.

In vitro acclimatization of Curcuma longa under controlled iso-osmotic conditions.

In vitro acclimatization has been validated as the successful key to harden the plantlets before transplanting to ex vitro conditions. In the present study, we investigated the potential of different sugar types (glucose, fructose, galactose, sucrose) in regulating morphological, physiological and biochemical strategies, survival percentage and growth performance, and rhizome traits of turmeric under iso-osmotic potential. Leaf greenness (SPAD value) in acclimatized plantlets (4% glucose; -1.355 MPa osmotic potential) of 'ST018' was retained and greater than in 'PB009' by 1.69-fold, leading to maintain high Fv/Fm (maximum quantum yield of PSII), ΦPSII (photon yield of PSII) and Pn (net photosynthetic rate) levels, and retained shoot height, leaf length, leaf width, shoot fresh weight and shoot dry weight after one month upon transplanting to ex vitro conditions. In addition, Pn, Ci (intracellular CO2), gs (stomatal conductance) and E (transpiration rate) in acclimatized plantlets (6% sucrose; -1.355 MPa osmotic potential) of 'PB009' were stabilized as physiological adapted strategies, regulating the shoot and root growth and fresh and dry weights of mini-rhizome. Interestingly, the accumulation of total curcuminoids in mini-rhizome derived from 6% sucrose acclimatized plantlets of 'ST018' was greater than in 'PB009' by 3.76-fold. The study concludes that in vitro acclimation of turmeric 'PB009' and 'ST018' using 6% sucrose and 4% glucose, respectively, promoted percent survival, physiological adaptations, and overall growth performances under greenhouse conditions.