Edible nanoparticles (ENPs) are nano-sized vesicles derived from edible plants. These ENPs are loaded with plant derived microRNAs, protein, lipids and phytochemicals. Recently, ginger derived ENPs was shown to prevent inflammatory bowel diseases and colon cancer, in vivo, highlighting their therapeutic potential. Conventionally, differential centrifugation with an ultra-centrifugation step is employed to purify these ENPs which imposes limitation on the cost-effectiveness of their purification. Herein, we developed polyethylene glycol-6000 (PEG6000) based ginger ENP purification (PEG-ENPs) method, which eliminates the need for expensive ultracentrifugation. Using different PEG6000 concentrations, we could recover between 60% to 90% of ENPs compared to ultracentrifugation method. PEG-ENPs exhibit near identical size and zeta potential similar to ultra-ENPs. The biochemical composition of PEG-ENPs, such as proteins, lipids, small RNAs and bioactive content is comparable to that of ultra-ENPs. In addition, similar to ultra-ENPs, PEG-ENPs are efficiently taken up by the murine macrophages and protects cells from hydrogen peroxide induced oxidative stress. Since PEG has been approved as food additive, the PEG method described here will provide a cost-effective alternative to purify ENPs, which can be directly used as a dietary supplement in therapeutic formulations.

Plant-derived nanoparticles (PDNPs) are naturally occurring exosome-like nanovesicles derived from dietary plants containing key plant bioactives. Ginger-derived PDNPs have a therapeutic effect on alcohol-induced liver injury, inflammatory bowel disease, and colon cancer. PDNPs are conventionally purified by differential ultracentrifugation, a technique not amenable for scale up. We have recently developed a polyethylene glycol (PEG) 6000-based method for cost-effective purification of ginger PDNPs, with comparable efficiency to differential ultracentrifugation (Sci. Rep.2020, 10 (1), 4456.). Herein, we report a 4–5-fold higher ginger PDNP recovery when PEG precipitation was carried out in low pH conditions (pH 4 and 5). Low pH-derived ginger PDNPs were smaller in size without an overt change in zeta potential. The spontaneous intracellular entry and protection against oxidative stress in A431 cells were similar between ginger PDNPs purified under low, neutral, and alkaline pH. Low-pH purified ginger PDNPs had higher levels of total polyphenolic content compared to PDNPs purified under neutral and alkaline pH. Recently, ginger PDNP-derived microRNAs have been shown to exhibit cross-kingdom regulation by targeting human, gut microbiome, and viral transcripts. Using qRT-PCR, we also verified the presence of miRNAs that were predicted to target SARS-CoV-2 in ginger PDNPs purified under low pH. Thus, we have developed a method to purify ginger PDNPs in high yields by using low-pH conditions without affecting the major bioactive contents of PDNPs.

Long noncoding RNAs (lncRNAs) constitute a major, but poorly characterized part of human transcriptome. Recent evidence indicates that many lncRNAs are involved in cancer and can be used as predictive and prognostic biomarkers. Significant fraction of lncRNAs is represented on widely used microarray platforms, however they have usually been ignored in cancer studies.

Leishmania donovanipromastigote membrane antigens (LAg) encapsulated in positively charged liposomes have been found to induce very significant levels of protection against experimental visceral leishmaniasis. The protectively immunized animals exhibited profound delayed-type hypersensitivity and antibody responses. The extent of protection induced by the same antigens, however, varied depending on the charge of the vesicles, with maximum induction by positively charged liposomes, followed by neutral liposomes and last negatively charged liposomes. Characterization of LAg and LAg entrapped in liposomes of different charges by Western blot analysis revealed the immunodominance of gp63 in all three vaccine preparations. The strong reactivity of antigens in a restricted antigen profile that included, in addition to gp63, 72-, 52-, 48-, 45-, 39-, and 20-kDa components in neutral and positively charged liposomes contrasted with the reactivity of a greater number of LAg components in negatively charged liposomes. Resistance to visceral leishmaniasis appears to depend on the immunity induced by gp63 and a few select antigens in association with the right liposomes. A striking similarity between the immunogenic profile of partially purified soluble antigens and that of LAg in neutral and positively charged liposomes suggests the potentiality of these antigens in future vaccine studies ofL. donovani.