Cyclodextrin glycosyltransferase (CGTase) is an enzyme that produces cyclodextrins (CDs) from starch and related carbohydrates, producing a mixture of α-, β-, and γ-CDs in different amounts. CGTase production, mainly by Bacillus sp., depends on fermentation conditions such as pH, temperature, concentration of nutrients, carbon and nitrogen sources, among others. Bacillus megaterium CGTase produces those three types of CDs, however, β-CD should prevail. Although, waxy corn starch (CS) is used industrially to obtain CGTase and CDs because of its high amylopectin content, alternative sources such as amaranth starch (AS) could be used to accomplish those purposes. AS has high susceptibility to the amylolytic activity of CGTase because of its 80% amylopectin content. Therefore, the aim of this work was evaluate the AS as carbon source for CGTase production by B. megaterium in a submerged fermentation. Afterwards, the CGTase was purified partially and its activity to synthesize α-, β-, and γ-CDs was evaluated using 1% AS as substrate. B. megaterium produced a 66 kDa CGTase (Topt = 50°C; pHopt = 8.0), from the early exponential growth phase which lasted 36 h. The maximum CGTase specific activity (106.62 ± 8.33 U/mg protein) was obtained after 36 h of culture. CGTase obtained with a Km = 0.152 mM and a Vmax = 13.4 μM/min yielded 40.47% total CDs using AS which was roughly twice as much as that of corn starch (CS; 24.48%). High costs to produce CDs in the pharmaceutical and food industries might be reduced by using AS because of its higher α-, β- and γ-CDs production (12.81, 17.94, and 9.92%, respectively) in a shorter time than that needed for CS.

Objective: The encapsulation of bioactive compounds of food interest provide protection against ambiental factors and degradation reactions. Therefore, the encapsulation of these compounds, was studied and analyzed considering the applications, current advances, challenges, and opportunities on the topic. Design/methodology/approach: Wall materials, bioactive compounds of food interest, encapsulation methods, applications, current advances, challenges, and opportunities in encapsulation of bioactive compounds were explored, described, and discussed considering the principal literature on the topic, and scientific databases were used for the bibliographic research. Results: Encapsulation process is a novel technology that allows the increasing the stability of aromas, flavors, pigments, and microorganisms, beside of improve the sensory, physical chemical and functional properties, quality, and the extend the shelf-life. Limitations on study/implications: Foods contain bioactive compounds that are susceptible to oxidation and degradation, which can reduce their quality and shelf life. To preserve these compounds, is important to develop other encapsulation systems considering alternative wall materials from different sources that can be applied under different process conditions from laboratory, pilot to industrial scale.  Findings/conclusions: Encapsulation process provide protection to bioactive compounds enhancing the sensory, physical chemical and functional properties, quality, and extend the shelf-life considering the integral and sustainable use of agricultural products.

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Objective: Determine which agricultural practices are currently used by corn (Zea mays L.) growers in the municipality of Jilotepec, Estado de México. Design/methodology/approach: An individual survey composed of both open and close-ended questions was applied to 93 corn producers from the municipality of Jilotepec, Estado de México, in order to obtain information about the planting practices they carry out. From there, 10 producers were selected for on-site monitoring their plots.  Results: Maize growers in Jilotepec, Estado de México, are conscious of the genetic and cultural richness of native maize. However, the agricultural practices they use for their production are centered on the conventional agricultural model using chemical compounds obtained by chemical synthesis and a part is focused on monoculture production. Study limitations/implications: The applied survey consisted of 13 questions, and the main limitation was the fact that it was not an extensive questionnaire because it is hard for people to devote a lot of time to this kind of polls; it is known that few questions generate more accurate information, while detailed polls have high levels of inaccuracy. Findings/Conclusions: The results of this study showed that most of the producers are dedicated to growing native corn with a single crop per year and do not use any agroecological practices for their production or only very limited ones; they are also convinced that it is important to preserve native corn as it is a wealth for the Mexican people.