Enzymatic hydrolysis of a colloidal system based on cape gooseberry

Deciphering the Cape Gooseberry Fruits Mycobiome for Further Safety Improvement Postharvest

Cape gooseberries are exquisitely flavored fruits; their rapid deterioration reduces their shelf life. Understanding the unique mycobiome of fruit peels is an essential step in identifying the taxa causing postharvest loss. The current study proposes to analyze the fungal communities of cape gooseberry peels collected from an organic orchard at unripe and ripe stages and purchased from open-air market sites, using the ITS2 region metabarcoding. According to the Kruskal-Wallis test, there were no statistically significant differences found in either the phylogenetic or non-phylogenetic alpha diversity indices. Significant differences in fungal communities were observed between the market and orchard groups based on beta diversity results. Ascomycota (85.72-96.76%), Basidiomycota (3.21-13.91%), and Chytridiomycota (0.07-9.35%) were the most common fungal phyla, their abundance varying with the ripening stage and origin. Dothideomycetes in the orchard group and Saccharomycetes in the market group were the two most prevalent classes. Furthermore, we investigate which taxa showed a significant difference in abundance between the two conditions (market vs. orchard) using the analysis of compositions of microbiomes with bias correction (ANCOM-BC) test. Regardless of the phase, the orchard samples exhibited a notable increase in the mean absolute abundance of various beneficial fungal taxa, including Tilletiopsis washingtonensis and Articulospora proliferata, whereas the market samples demonstrated a high abundance of harmful yeasts and molds such as Meyerozyma guilliermondii, Candida railenensis, and Botrytis caroliniana. Although it is unclear how these microorganisms augment at the market sites and might impact the fruit quality after harvest, from a fruit safety perspective, it is essential to comprehend the diversity and variation of the mycobiome composition at different ripening stages to further develop strategies to improve food safety postharvest.

Bacterial community structure of Physalis peruviana L. fruit exocarp and the presence of pathogens with possible implications on food safety

Introduction

Cape gooseberry (Physalis peruviana L.) is a wellconsumed crop in Ecuador, whose fruits are abundant in bioactive molecules. Its rapid post-harvest deterioration and safety limit its market potential.

Methodology

To gather baseline data on the prevalence of bacterial taxa among groups, we employed 16S ribosomal RNA (16S rRNA) amplicon gene sequencing to detect changes in the bacterial community structure in cape gooseberry fruits harvested from an organic farm production system (# 270 samples x two ripeness stages), and fruits obtained from an open-air market (#270).

Results

This is the first report of bacterial taxa inhabiting cape gooseberry fruits. Shannon's diversity index revealed that the fruits purchased from the market and the unripe stage had the highest level of bacterial diversity (average Shannon indices of 3.3 and 3.1) followed by those collected from the field at the mature ripe stage (2.07). Alpha diversity analysis indicated that there were no significant differences in the number of taxa or evenness within the sample, whereas there was a significant difference in beta diversity between the groups. Rhizobiaceae was the most abundant family in fruits originating from the field regardless of the ripe stage, while Acetobacteraceae, Pseudomonadaceae, Fusobacteriaceae, Bacteroidaceae, and Erwiniaceae were the most abundant families in the market group. At the genus level, Liberibacter was the most abundant phytopathogen in fruits originating from the field, while Gluconobacter was the most abundant in samples collected from the market. The phytopathogen Candidatus_Liberibacter was the most abundant in samples collected from the field, while the fruits purchased from the market stands contained opportunistic enteric pathogens such as Escherichia vulneris, Klebsiella pneumoniae, and K. variicola, their relative abundance varied with the sample. In addition, potential pathogens of animal origin such as Fusobacterium necrophorum, Porphyromonas levii, Helcococcus ovis, and Trueperella pyogenes were found in almost all samples at varying relative abundance.

Conclusion

Our study provides basic information on the microbiome of cape gooseberries from agriculture fields to the table along with the detection of several pathogenic microorganisms with possible impact on food safety and public health therefore, strategies for reducing bacterial contamination in both farm and retail markets are compulsory.