Effect of Microwave and Ultrasound during the Killing Stage of the Curing Process of Vanilla (Vanilla planifolia, Andrews) Pods

Production, extraction, and authentication of natural and non-natural vanillin. A comprehensive review and economic future biotechnology perspectives

Vanillin is a chief flavoring agent owing to its immense popularity in food, beverage, and pharmaceutical industries. This study holistically dissects vanillin quality control approaches that include conventional, hyphenated, and sensory analyses. Markers to differentiate between authentic, synthetic, and adulterated vanilla are highlighted using hyphenated techniques. Carbon isotope ratio range appears of potential to identify vanillin originating from biosynthetic (C3 plant), synthetic (petroleum) sources, or vanilla pods. Novel extraction methods typically provide greater selectivity, higher purity, shorter extraction times, and ecofriendly attributes compared to conventional methods. Best methods include supercritical fluids (SCF) or natural deep eutectic solvents (NADES) that promoted higher yield of vanillin. The review also highlights the promising avenue of biotransformation, the safest technique for the production of vanilla flavor components, tackling current challenges and emphasizing its potential to meet the market needs for authenticated and high-quality yields of vanillin.

Effect of different killing methods during curing on the phytochemical and bacterial composition of Vanilla planifolia using multi-omic approaches

Vanilla planifolia Jacks. ex Andrews, is cultivated for its aromatic pods, obtaining the primary source of vanillin, a molecule valued for its flavor and bioactivity. Mexico ranks among the top five global producers, and Papantla, Veracruz, contributes 70 % of national production. Developing vanilla's characteristic aroma involves a curing process composed of killing, sweating, drying, and conditioning, which enzymatic reactions and microbial activity play essential roles. This study assessed the impact of four killing treatments: microwave, hot water immersion, sonication, and freezing on the phenolic composition and bacterial communities in vanilla curing through metabolomic and 16S sequencing approaches. Freezing treatment resulted in the most substantial changes in phenolic profiles, including higher vanillin concentrations. Bacillus was the dominant bacterial genus, with hot water immersion and sonication showing the greatest α-diversity. These findings underscore the value of omic sciences in refining curing processes, enabling producers to achieve higher-quality vanilla through more efficient and technical methods.

Enhancement of phenolic compounds in vanilla curing with the application of UVC light, microwaves and ultrasound

Short-wave ultraviolet light at 254 nm (UVC light) was evaluated at different doses (0.9, 2.16, 4.50 and 7.16 J/m2) to increase phenolic compounds and analyze its effect on the native microbial flora present on vanilla (Vanilla planifolia) beans (VB). Subsequently, microwave and ultrasound treatments were applied, individually or in combination, at different powers levels (1100 and 600 W) and amplitudes (50 and 90%) during the curing process. In the UVC light treatment, a dose 2.16 J/m2 was the optimal, resulting in a 74% increases in total phenolic compounds (TPC) in VB compared to the control. During the curing process of the irradiated VB, the combination of microwave (600 W) and ultrasound (50% amplitude) resulted in 37.909 ± 0.52 mg GAE/g d.m. of TPC, while non-irradiated pods showed 29.869 ± 0.54 mg GAE/g d.m. at 50 days. This methodology offers several advantages, such as eliminating the need for tedious handling and skilled labor.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-024-06061-6.

The isolation and identification of Bacillus velezensis ZN-S10 from vanilla (V. planifolia), and the microbial distribution after the curing process

The market value of vanilla beans (Vanilla planifolia) is constantly increasing due to their natural aroma and flavor properties that improve after a curing process, where bacteria colonization plays a critical role. However, a few publications suggest that bacteria play a role in the curing process. Hence, this study aimed to isolate Bacillus sp. that could be used for fermenting V. planifolia while analyzing their role in the curing process. Bacillus velezensis ZN-S10 identified with 16S rRNA sequencing was isolated from conventionally cured V. planifolia beans. A bacteria culture solution of B. velezensis ZN-S10 (1 mL of 1 × 107 CFU mL-1) was then coated on 1 kg of non-cured vanilla pods that was found to ferment and colonize vanilla. PCA results revealed distinguished bacterial communities of fermented vanilla and the control group, suggesting colonization of vanilla. Phylogenetic analysis showed that ZN-S10 was the dominant Bacillus genus member and narrowly correlated to B. velezensis EM-1 and B. velezensis PMC206-1, with 78% and 73% similarity, respectively. The bacterial taxonomic profiling of cured V. planifolia had a significant relative abundance of Firmicutes, Proteobacteria, Cyanobacteria, Planctomycetes, and Bacteroidetes phyla according to the predominance. Firmicutes accounted for 55% of the total bacterial sequences, suggesting their colonization and effective fermentation roles in curing vanilla.

Ameliorative effects of vanillin against pentylenetetrazole-induced epilepsy and associated memory loss in mice: The role of Nrf2/HO-1/NQO1 and HMGB1/RAGE/TLR4/NFκB pathways

BACKGROUND

Epilepsy is a severe neurological disorder associated with substantial morbidity and mortality. Vanillin (Van) is a natural phenolic aldehyde with beneficial pharmacological properties. This study investigated the neuroprotective effects of Van in epilepsy and elucidated its mechanism of action.

METHODS

Swiss albino mice were divided into the following five groups: "normal group", 0.9 % saline; "pentylenetetrazole (PTZ) group", intraperitoneal administration of 35 mg/kg PTZ on alternate days up to 42 days; and "PTZ + Van 20", "PTZ + Van 40", and "PTZ + sodium valproate (Val)" groups received PTZ injections in conjunction withVan 20 mg, Van 40 mg/kg, and Val 300 mg/kg, respectively. Behavioural tests and hippocampal histopathological analysis were performed in all groups. The Nrf2/HO-1/NQO1 and HMGB1/RAGE/TLR4/NFκB pathways, oxidative stress, neuro-inflammation, and apoptotic markers were analysed. Furthermore, brain acetylcholinesterase (AChE) activity and levels of dopamine (DA), gamma-aminobutyric acid GABA, and serotonin 5-HT were assessed.

RESULTS

Van prolonged seizure manifestations and improved electroencephalogram (EEG)criteriain conjunction with 100 mg/kg PTZ once daily. Van administration increased Nrf2/HO-1/NQO1 levels, with subsequent attenuation of malondialdehyde (MDA) and nitric oxide (NO) levels with elevated glutathione (GSH) levels and intensified superoxide dismutase (SOD) and catalase activities. Van reduced the gene and protein expression of HMGB1/RAGE/TLR4/NFκB and decreased the levels of inflammatory and apoptotic markers. In addition, Van reduced AChE activity, and elevated glial fibrillary acidic proteins (GFAP) increased neurotransmitter and brain-derived neurotrophic factors (BDNF).

CONCLUSION

By increasing Nrf2/HO-1/NQO1 levels and downregulating the HMGB1/RAGE/TLR4/ NFκB pathway, Van offered protection in PTZ-kindled mice with subsequent attenuation in lipid peroxidation, upregulation in antioxidant enzyme activities, and reduction in inflammation and apoptosis.