Analysis of the bacterial diversity in Moroccan Jben cheese using TTGE, DGGE, and 16S rRNA sequencing.

This research investigated the physicochemical, microbiological, and bacterial diversity of Jben cheese, a popular artisanal variety in Morocco. The bacterial diversity was explored using culture-independent methods, including temporal temperature gel electrophoresis (TTGE), denaturing gradient gel electrophoresis (DGGE), and high-throughput sequencing (HTS). Significant intra-sample differences were observed for most physicochemical parameters within each milk type, while inter-sample differences occurred between cow and goat cheeses for dry matter and ash. Jben cheese exhibited distinct characteristics, with low pH values of 3.96, 4.16, and 4.18 for cow, goat, and mixed cheeses, respectively. Goat cheeses had higher fat (49.23 g/100 g), ash (1.91 g/100 g), and dry matter (36.39 g/100 g) than cow cheeses. All cheeses displayed high microbial counts, with a notable prevalence of the lactic acid bacteria (LAB) group, averaging 8.80 ± 0.92 log CFU/g. Jben cheese also displayed high contamination levels with total coliforms, faecal coliforms, yeast, and molds. Fatty acid profiling revealed fraudulent practices in Jben cheese marketing, with cow or mixed cheeses sold as goat cheese, as proven by low capric acid concentration. HTS analysis of Jben cheese identified ten genera and twenty-four species, highlighting Lactococcus lactis as predominant. TTGE and DGGE confirmed the presence of L. lactis but failed to provide the detailed profile achieved through HTS analysis. HTS has been demonstrated to be more reliable, whereas TTGE/DGGE methods, though informative, were more time-consuming and less reliable. Despite limitations, the combined use of TTGE, DGGE, and HTS provided a comprehensive view of indigenous bacterial communities in Jben cheese, identifying L. lactis as the main species.

Promoting the growth of Sulla flexuosa L. by endophytic root nodule bacteria authors and affiliations.

Legume plants rely upon multipartite interactions between rhizobia and bacterial endophytes within root nodules to facilitate plant growth. This study aimed to isolate and identify indigenous endophytic bacteria from root nodules of Sulla aculeolata L. in Northeast Morocco. Based on their tri-calcium phosphate (TCP) solubilization capacity, five endophytes were chosen for further evaluation of their plant growth traits. All isolates were hydrogen cyanide (HCN) and siderophore producers, while only BCH24 tested positive for ACC deaminase activity. Indole-3-acetic acid (IAA) synthesis ranged from 1.27 mgL- 1 to 2.89 mgL- 1, while soluble phosphate concentrations was between 7.99 mg L- 1 and 110.58 mg L- 1. Additionally, all the endophytes were able to produce more than two lytic enzymes. Based on the analysis of 16 S rRNA gene sequences five isolates were identified as Enterobacter sp (BCH13, BCH2), Pseudomonas sp (BCH16, BCH24), and Serratia sp (BCH10). The strains inhibited the growth of three phytopathogenic fungi, with BCH13 exhibiting the highest rate against Aspergillus ochraceus (45%), followed by BCH24 against Fusarium oxysporum (40%) and Botrytis cinerea (35%), respectively. In vivo inoculation of halotolerant strains Enterobacter hormaechei (BCH13) and Pseudomonas moraviensis (BCH16) under gnotobiotic conditions revealed that co-inoculation with Rhizobium sullae KS6 improved plant development compared to single inoculation, making it a promising eco-friendly bio-inoculant for legume Sulla flexuosa L. production.

Effect of lead stress on mineral content and growth of wheat (Triticum aestivum) and spinach (Spinacia oleracea) seedlings.

Lead (Pb) is the most common heavy metal contaminant in the environment. Pb is not an essential element for plants, but they absorb it when it is present in their environment, especially in rural areas when the soil is polluted by automotive exhaust and in fields contaminated with fertilizers containing heavy metal impurities. To investigate lead effects on nutrient uptake and metabolism, two plant species, spinach (Spinacia oleracea) and wheat (Triticum aestivum), were grown under hydroponic conditions and stressed with lead nitrate, Pb(NO3)2, at three concentrations (1.5, 3, and 15 mM). Lead is accumulated in a dose-dependent manner in both plant species, which results in reduced growth and lower uptake of all mineral ions tested. Total amounts and concentrations of most mineral ions (Na, K, Ca, P, Mg, Fe, Cu and Zn) are reduced, although Mn concentrations are increased, as its uptake is reduced less relative to the whole plant's growth. The deficiency of mineral nutrients correlates in a strong decrease in the contents of chlorophylls a and b and proline in both species, but these effects are less pronounced in spinach than in wheat. By contrast, the effects of lead on soluble proteins differ between species; they are reduced in wheat at all lead concentrations, whereas they are increased in spinach, where their value peaks at 3 mM Pb. The relative lead uptake by spinach and wheat, and the different susceptibility of these two species to lead treatment are discussed.