A novel technique for the preparation of curd (Dahi) by PVDF membrane-based strip.

Preparation of curd at home is quite challenging as it requires skills like addition of proper amount of starter culture, maintenance and storage of inoculum for the preparation of good and consistent quality curd. The present work utilized bacterial attachment property of PVDF (Polyvinylidene fluoride) membrane to prepare a strip which can be dipped into milk for the preparation of consistent quality curd. Shelf-life of the strip is around 100 days. The strip prepared curd was well comparable with the curd prepared by the commercial inoculum based on their pH, % lactic acid, % syneresis and bacterial load. Strip of size 5 × 5 cm2 was enough for preparation of 500 mL curd. It was proved by different analytical techniques like AFM, SEM and FTIR that PVDF was not having any leaching property during curd preparation. It can also be used in repeated contact with food products, as it is FDA (Food and Drug Administration) compliant and non-toxic. The curd strip has significant industrial relevance as it is a cost-effective alternative of any commercial inoculum (very expensive) and also meets the demand of consumers with the rising health awareness and busy lifestyles. Further, it is spillage proof, portable, ready-to-use. Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-021-05339-3.

Market-ready U-AST kit: simple, fast, cost-effective solution for concurrently detecting urinary tract infection and antibiotic resistance.

There is an increasing demand for an inexpensive, quick, accessible, and simple method for the detection of urinary tract infection (UTI) together with the antibiotic-resistance profile of the infection-causing bacteria. Our primary goal is to assist doctors in prescribing antibiotics that will quickly treat infections and reduce the likelihood of antibiotic resistance spreading throughout the community. To this end, a urinary tract infection antibiotic-sensitivity test (U-AST) kit was developed for the validation of bacterial infection in the urinary tract and determination of the antibiotic-resistance profile of the bacteria in a short time. The U-AST kit was standardized using standard strains of bacteria, specifically Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, Vibrio cholerae, and Pseudomonas species. Further, the kit was validated using 50 clinical urine samples with variation in their physical and chemical parameters, and the resistance pattern against five therapeutically important antibiotics were tested. The results acquired using the U-AST kit showed a 100% similarity to those acquired using the laboratory-based gold standard method. Interestingly, the U-AST kit required a maximum of 9 h to understand the bacterial contamination and resistance profile of the bacterial community, which was observed by a simple color change. The same result can be obtained using the gold standard method but requires 36-72 h, a sophisticated microbiology method, and skilled microbiologists. Other methods can also predict infection quickly with the aid of sophisticated instrumentation; however, understanding the antibiotic-resistance pattern is not possible. To the best of our understanding, this is a unique technique for the quick, easy, and inexpensive detection of UTI with antibiotic sensitivity testing and does not require a special laboratory set-up or expert personnel. The commercialization of the developed clinically validated U-AST kit is currently underway.

Determination of antibiotic resistance profile of bacterial community from environmental water using antibiotic-resistant bacterial contamination detection (ABCD) kit.

Quick and easy monitoring approaches are needed to assess sources, clinical relevance, and incidences of antibiotic resistance in environmental bacterial communities. In the present work, antibiotic-resistant bacterial contamination detection (ABCD) kits were developed for the same. The method was standardized with strains of Escherichia coli TS7, Staphylococcus arlettae HWI8, Enterococcus faecalis HWI19, and Aerococcus viridans HWII16 with known antibiogram using six clinically important antibiotics. The method was verified with different water sources having different physicochemical parameters successfully. Only 1 ml of sample water is required to be mixed with an optimized concentration of the antibiotic solution and incubated for 6h; subsequently, a color change to pink may be observed within a specified amount of time upon the addition of the bacterial detection PVDF membrane to monitor the presence of resistant bacteria. There is no color change in the case of antibiotic-susceptible bacterial communities or the absence of a resistant community. Moreover, the time taken for color change is inversely related to the magnitude of the antibiotic-resistant communities in terms of enumeration. Up to our understanding, this is the 1st report which can determine an antibiotic-resistance profile of any water source by observing only color change within a maximum of 7 h (6 h for co-culture of bacteria and antibiotics + 1 h for color change detection) time without the aid of any microbiology laboratory or skilled manpower.