Meta-analysis of the effects of gamma irradiation on chicken meat and meat product quality.

Background and Aim: Irradiation is one of the most effective microbial decontamination treatments for eliminating foodborne pathogens and enhancing chicken meat safety. The effect of gamma irradiation on the overall quality of chicken meat and its products must be observed to provide a comprehensive explanation to the public. This meta-analysis examined the effects of gamma irradiation on the oxidation parameters, microbial activity, physicochemical characteristics, sensory parameters, and nutrient quality of chicken meat and meat products. Materials and Methods: We conducted a literature search using various search engines (Scopus®, PubMed®, and Google Scholar®) with "irradiation," "gamma," "chicken," and "meat" as keywords. Gamma irradiation treatment was set as a fixed effect, and the difference between experiments was set as a random effect. This study used a mixed-model methodology. After evaluation, we selected 43 articles (86 studies) for inclusion in the database. Results: Gamma irradiation significantly increased (p < 0.01) thiobarbituric acid-reactive substance levels on days 0, 7, and 14 of storage. Gamma irradiation reduced total aerobic bacteria, coliforms, Salmonella, yeast, and mold activity (p < 0.01). According to our meta-analysis, 21.75 kGy was the best dose for reducing total aerobic bacteria. On day 0, gamma irradiation did not affect the color parameters (L*, a*, b*). However, a significant difference (p < 0.01) was noted for a* and b* parameters between the control and irradiation treatments at 7 and 14 days. Although irradiation treatment was less consistent in sensory parameters, overall acceptability decreased on days 0, 7, and 14 after storage (p < 0.05). Regarding nutrient composition, gamma irradiation reduced moisture content and free fatty acid (FFA) content (p < 0.05). Although irradiation significantly reduces the microbial population, it increases the oxidation of chicken meat and its products. Irradiation decreases FFA content and overall acceptability, but it does not affect flavor, tenderness, juiciness, or cooking loss. Conclusion: Gamma irradiation positively reduces the microbial activity in chicken meat and its products but increases the oxidation parameters. Although gamma irradiation does not alter the flavor, tenderness, juiciness, or cooking loss, gamma irradiation can reduce the FFA content and overall acceptability.

Phytochemical analysis, antioxidant, α-glucosidase inhibitory activity, and toxicity evaluation of Orthosiphon stamineus leaf extract.

Ocimum aristatum, commonly known as O. stamineus, has been widely studied for its potential as an herbal medicine candidate. This research aims to compare the efficacy of water and 100% ethanolic extracts of O. stamineus as α-glucosidase inhibitors and antioxidants, as well as toxicity against zebrafish embryos. Based on the study findings, water extract of O. stamineus leaves exhibited superior inhibition activity against α-glucosidase, ABTS, and DPPH, with IC50 values of approximately 43.623 ± 0.039 µg/mL, 27.556 ± 0.125 µg/mL, and 95.047 ± 1.587 µg/mL, respectively. The major active compounds identified in the extract include fatty acid groups and their derivates such as linoleic acid, α-eleostearic acid, stearic acid, oleanolic acid, and corchorifatty acid F. Phenolic groups such as caffeic acid, rosmarinic acid, 3,4-Dihydroxybenzaldehyde, norfenefrine, caftaric acid, and 2-hydroxyphenylalanine and flavonoids and their derivates including 5,7-Dihydroxychromone, 5,7-Dihydroxy-2,6-dimethyl-4H-chromen-4-one, eupatorin, and others were also identified in the extract. Carboxylic acid groups and triterpenoids such as azelaic acid and asiatic acid were also present. This study found that the water extract of O. stamineus is non-toxic to zebrafish embryos and does not affect the development of zebrafish larvae at concentrations lower than 500 µg/mL. These findings highlight the potential of the water extract of O. stamineus as a valuable herbal medicine candidate, particularly for its potent α-glucosidase inhibition and antioxidant properties, and affirm its safety in zebrafish embryos at tested concentrations.

Facile fabrication of chitosan Schiff bases from giant tiger prawn shells (Penaeus monodon) via solvent-free mechanochemical grafting.

Fabrication of chitosan Schiff bases (ChSB) from giant tiger prawn shells (Penaeus monodon) using an environmentally friendly method has been conducted successfully. Transformation of Prawn Shells (PS) as raw material into chitin then chitosan was executed under ambient temperature. Later, three Ch Schiff bases (ChSB-A, ChSB-S, and ChSB-V) were successfully synthesized for the first time via solvent-free mechanochemical grafting with 2-hydroxy benzaldehyde, 4-methoxy benzaldehyde, and 3-methoxy-4-hydroxy benzaldehyde, respectively. Synthesis was carried out with Shaker Mill-Ultimate Gravity equipped with a Teflon jar with zirconia balls; then the product was characterized. FTIR analysis proved the conversion of free amine to imine groups. The degree of substitution (DS) and crystallinity index (CrI) were determined by elemental analysis and X-ray diffraction. The DS values obtained were about 0.343, 0.795, and 0.055 for ChSB-A, ChSB-S, and ChSB-V, respectively. The CrI of ChSB-A, ChSB-S, and ChSB-V was 53.3, 51.7, and 46.9 %, respectively. The thermal gravimetric analysis showed that the mechanochemical grafting of Ch improves the thermal stability of ChSB. This developed method provides a novel potential technique to convert PS into ChSB products by solvent-free mechanochemical grafting.