Journal of Experimental and Molecular Biology

Biochemical and molecular characterization of fermented cabbage and soybeans using starter culture

2025-07-22T05:49:59+00:00

The aim of this study was to characterize starter cultures of LAB (lactic acid bacterium) and Bacillus spp. for controlled fermentation of cabbage and soybeans to achieve desired products. Cultured isolates were studied morphologically and revalidated using biochemical and molecular methods. Extracted DNA was amplified using two specific primers. Banding pattern at 1500bp showed the presence of LAB and Bacillus subtilis DNA amplified. La57 primer amplified amino acid antiporter gene that identified LAB while ENIF primer amplified endoglucanase gene that identified B. subtilis. The16S ribosomal RNA was sequenced using the Sanger’s method for strain specific identification. As a result, the test organisms were morphologically identified as Pediococcus spp and B. subtilis. They differed in the type enzyme production (4:7 respectively). Sequence alignment identified them as Pediococcus pentosaceus strain DSM20336 (LAB) and B. subtilis subsp. subtilis strain 168. This is the novelty in this work. Results showed that P. pentosaceus induced ferments contained the least number of isolates in cabbage (Lactobacillus spp., Streptococcus spp. and Pediococcus spp) and soybean (Bacillus spp., Streptococcus spp. and Pediococcus spp) unlike in spontaneous fermentation where 8-9 bacterial isolates were recorded. The study identified potential fermenting strains of bacteria that could be employed as potential starter culture in the industrial fermentation of vegetable and legume foods to boost food security in Nigeria. These findings have industrial and economic benefits.

BIOACTIVITY AND PHYTOCHEMISTRY OF GUIERA SENEGALENSISJ.F.GMEL (COMBRETACAE)

2025-09-10T08:20:16+00:00

The phytochemical constituents of Guiera senegalensis, a widely used traditional medicinal plant in Africa, were investigated for their potential biological activities. Ethanolic extracts of G. senegalensis leaves were fractionated, and the resulting fractions were analyzed using GC-MS and NMR techniques. Forty compounds were identified by comparing their spectral data with published references. The hexane extract exhibited promising anti-leishmanial activity against Leishmania major, with an IC₅₀ of 16.69 ± 0.3 µg/mL. The ethyl acetate fraction showed moderate activity (IC₅₀ = 89.63 ± 0.6 µg/mL), while dichloromethane fractions were inactive at concentrations exceeding 100 µg/mL. The extract demonstrated limited antibacterial activity, inhibiting only Bacillus subtilis with a 60.31% inhibition rate, and showed no antifungal effects. Cytotoxicity testing on 3T3 cells revealed less than 50% inhibition, indicating minimal toxicity at tested concentrations. These findings support the ethnopharmacological relevance of G. senegalensis and highlight its potential as a source of anti-leishmanial drug candidates.

TOXICOLOGICAL ASSESSMENT OF CARBON NANOMATERIALS ON LEMNA MINOR L.: INSIGHTS INTO PHYSIOLOGICAL AND BIOCHEMICAL ALTERATIONS

2025-09-10T08:20:04+00:00

Synthetic carbon-based nanomaterials, such as multi-walled carbon nanotubes (MWCNTs), carboxyl-functionalized nanotubes (MWCNTs-COOH), and fullerene soot, are increasingly being utilised in practical industrial and agricultural applications. This reality raises concerns about their potential unfavourable ecotoxicological impact on aquatic ecosystems where they may accidentally end up. In this context, the present research aimed to evaluate several physiological and biochemical responses of plants belonging to the species Lemna minor L. when interacting with these types of nanomaterials, experimentally added at two concentrations (50 and 200 mg/L) to their culture medium over a 14-day cultivation period.

The results obtained demonstrated the appearance in the test plants of functional effects dependent on the dose and nature of the tested nanomaterial, reflected by significant changes in photosynthetic performance (decreases in the content of photo-assimilatory pigments and the efficiency of photosystem II), as well as by the activation of biochemical markers of oxidative stress (increases in the content of flavonoids and polyphenols, changes in POD and SOD activities). The functionalized nanotubes (MWCNTs-COOH) induced the most pronounced biochemical responses, while fullerene soot had more moderate effects, possibly due to its reduced bioavailability in the cultivation media.

The results highlight the sensitivity of Lemna minor to chemical stress generated by synthetic carbon-based nanomaterials present in the cultivation medium, thus confirming its usefulness as a model organism in ecotoxicological studies and emphasising the need for rigorous assessments regarding the potential impact of these nanomaterials on aquatic plants in natural ecosystems, to lay the groundwork for responsible ecological management strategies.