Direct and Rapid Detection and Quantification of Oenococcus oeni Cells in Wine by Cells-LAMP and Cells-qLAMP

Abstract

Fast detection and enumeration of Oenococcus oeni in winemaking are necessary to determine whether malolactic fermentation (MLF) is likely to be performed or not and to decide if the use of a commercial starter is needed. In other wines, however, performing MLF can be detrimental for wine and should be avoided. The traditional identification and quantification of this bacteria using culture-dependent techniques in wine-related matrices require up to 14 days to yield results, which can be a very long time to perform possible enological operations. Loop-mediated isothermal amplification (LAMP) is a novel culture-independent technique that amplifies nucleic acid sequences under isothermal conditions with high specificity and efficiency in less than 1 h with inexpensive equipment. We designed LAMP primers for the specific detection and quantification of O. oeni cells. The developed LAMP method allows O. oeni to be detected directly from both grape musts and wines within 1 h from the time that the LAMP reaction begins, and without DNA extraction and purification requirements. The high sensitivity of LAMP methodology is achieved by previous mechanical cells lysis with no further purification by detecting one single cell per reaction in culture media, and in white/red grape musts and wines by avoiding reaction inhibition by ethanol, polyphenols, and other wine inhibitors. Cells can be concentrated prior to the LAMP reaction to further increase this sensitivity. Moreover, the LAMP method does not require expensive equipment and can be easily operated. The developed method is both economic and fast and offers high sensitivity and specificity.

The Identification of Yak Meat Using Loop-Mediated Isothermal Amplification Method Coupled with Hydroxy Naphthol Blue for the Prevention of Food Fraud

“…The determination of LAMP results typically involves turbidity detection or agarose gel electrophoresis [19,20], which require specialized facilities and equipment that are always unavailable in most grassroots settings due to their limited resources [21,22]. The detection of LAMP results relies on color changes resulting from the introduction of dyes into the reaction system [23].…”

A quantitative RT‐qLAMP for the detection of SARS‐CoV‐2 and human gene in clinical application

“…Similar to qPCR, presumably a quantitative LAMP, termed as ‘qLAMP’, could also be used to evaluate the viral load of SARS‐CoV‐2. qLAMP has been used to assess different viruses and pathogens in previous works using fluorescent reading (Cao et al, 2017 ; Ongerth & Danielson, 2021 ; Soares‐Santos et al, 2018 ; Yang et al, 2017 ) and colorimetric reading (Nguyen et al, 2020 ). In this work, the RT‐qLAMP assay was developed to quantify RNA of SAR‐CoV‐2 based on the threshold time (TT) value.…”

Detection of Streptococcus pneumoniae in Urine by Loop-Mediated Isothermal Amplification

“…13 Finally, the direct visualization of the results (amplicons) is possible based on the presence of turbidity, or by fluorescence or colorimetric detection. [13][14][15][16][17] DNA-based detection methods used for S. pneumonia commonly utilize blood pleural fluid and nasopharyngeal aspirates, induced sputum, and nonbronchoscopic bron-choalveolar lavage fluid samples. 4,18 Compared with these other types of biofluids, urine offers several advantages for children, including its convenience of sampling and its ease of use for handling and storing.…”