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Potato trypsin inhibitor (PTI) was obtained from imitated potato wastewater through a sustainable method of sequential acid precipitation, salting out, and ultrafiltration. PTI had a favorable inhibition with the low IC 50 of 6.861 ± 0.107 mg/L. To explore stability of PTI against pH and heating treatment, PTI secondary structure was investigated by circular dichroism and inhibition was determined using the BAPNA method. The results indicated that PTI exerted a certain heat resistance and excellent stability over a wide pH range. Also, correlation analysis displayed β-sheet and β-turn contents of PTI had a positive correlation with inhibition, whereas α-helix and random coil contents were negatively correlated with inhibition. During in vitro digestion, the limited loss rate of activity (29.28%) and degree of hydrolysis (24.39%) suggested that PTI presented sufficient resistance to gastrointestinal digestion. These findings would extend beneficial hints to convert potato wastewater by-product into the potential anti-obesity ingredient in future., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

The modified rice starches by octenyl succinic anhydride (OS-RSs) with the same degree of substitution of 0.033 were prepared in aqueous solution using 3% or 20% (w/w) NaOH as a catalyst (OS-RS 3 or OS-RS 20). The results indicated that 20% of NaOH could destroy the structure of starch more seriously and led to more OS groups travelling to interior of starch granules. Furthermore, the storage stability and rheological properties of Pickering emulsions formulated by RS, OS-RS 3 and OS-RS 20 were investigated. Emulsion index of OS-RS 20 were always lower than OS-RS 3 during the storage time, while G', G" and viscosity of O/W Pickering emulsion formulated by OS-RS 20 particles were greater than those of OS-RS 3. OS-RS 3 with more hydrophobic groups in the granule surface could form more compact oil/water layers which contributed greater to the storage stability of Pickering emulsion due to the formation of more compact oil/water layers. However, OS-RS 20 with homogeneous distribution of OS groups in the whole particles resulted in the formation of a tighter droplet network structure that was more resistant to external impacts, which showed OS-RS 20 could improve the shear stability of Pickering emulsion., (Copyright © 2019 Elsevier Ltd. All rights reserved.)