The aflatoxin inhibitors capsaicin and piperine from Capsicum chinense and Piper nigrum fruits modulate the antioxidant system in Aspergillus parasiticus

Influence of Capsicum chinense concentration and salt varieties on the quality attributes of Kilishi, a sundried beef jerky

The impact of Capsicum chinense concentration and salt varieties on cholesterol oxides, physicochemical properties, microbial profiles and organoleptic attributes of Kilishi, a sundried beef jerky, was assessed. Kilishi (KL) was prepared from sundried strips of Biceps femoris and marinated with either 2 % Sodium chloride (NaCl) + 7 % fresh Capsicum chinense (CC) (KL-1), 1 % NaCl + 1 % Potassium chloride (KCl) + 7 % CC (KL-2), 1 % NaCl + 1 % Potassium citrate (C6H5K3O7) + 7 % CC (KL-3), 1 % NaCl + 14 % CC (KL-4), 1 % KCl + 14 % CC (KL-5) or 1 % C6H5K3O7 + 14 % CC (KL-6), and stored at 29 ± 1 °C for 90 d. The partial or total replacement of NaCl lowered (P < 0.05) the Na content in KL. The KL samples treated with 14 % CC had lower (P < 0.05) 25-hydroxy cholesterol, cholesta-3,5-dien-7-one, carbonyl, pH, malondialdehyde, and lightness and greater (P < 0.05) redness and Lactobacillus counts than those treated with 7 % CC. The chemical composition, sensory scores and water activity were unaffected by the additives. The taste, flavor, and overall acceptance scores of KL decreased (P < 0.05) after 30 days of storage. The substitution of KCl and C6H5K3O7 for NaCl and the increase in CC concentration from 7 to 14 % lowered the Na content and selected cholesterol oxides, respectively, without impairing the organoleptic traits of Kilishi.

Comprehensive review of the phytochemistry, pharmacology, pharmacokinetics, and toxicology of alkamides (2016-2022)

Alkamides refer to a class of natural active small-molecule products composed of fatty acids and amine groups. These compounds are widely distributed in plants, and their unique structures and various pharmacological activities have caught the attention of scholars. This review provides a collection of literatures related to the phytochemistry, pharmacological effects, pharmacokinetics, and toxicity of alkamides published in 2016-2022 and their summary to provide references for further development of this class of ingredients. A total of 234 components (including chiral isomers) were summarized, pharmacological activities, such as anti-inflammatory, antitumor, antidiabetic, analgesic, neuroprotective, insecticidal, antioxidant, and antibacterial, and miscellaneous properties of alkamides were discussed. In addition, the pharmacokinetic characteristics and toxicity of alkamides were reviewed. However, information on the pharmacological mechanisms of the action, drug safety, and pharmacokinetics of alkamides is limited and thus requires further investigation and evaluation.

SfgA Renders Aspergillus flavus More Stable to the External Environment

sfgA is known as a key negative transcriptional regulator gene of asexual sporulation and sterigmatocystin production in Aspergillus nidulans. However, here, we found that the homolog sfgA gene shows a broad and complex regulatory role in governing growth, conidiation, sclerotia formation, secondary metabolism, and environmental stress responses in Aspergillus flavus. When sfgA was deleted in A. flavus, the fungal growth was slowed, but the conidiation was significantly increased, and the sclerotia formation displayed different behavior at different temperatures, which increased at 30 °C but decreased at 36 °C. In addition, sfgA regulated aflatoxin biosynthesis in a complex way that was associated with the changes in cultured conditions, and the increased production of aflatoxin in the ∆sfgA mutant was associated with a decrease in sclerotia size. Furthermore, the ∆sfgA mutant exhibited sensitivity to osmotic, oxidative, and cell wall stresses but still produced dense conidia. Transcriptome data indicated that numerous development- and secondary-metabolism-related genes were expressed differently when sfgA was deleted. Additionally, we also found that sfgA functions downstream of fluG in A. flavus, which is consistent with the genetic position in FluG-mediated conidiation in A. nidulans. Collectively, sfgA plays a critical role in the development, secondary metabolism, and stress responses of A. flavus, and sfgA renders A. flavus more stable to the external environment.