Enhanced Antioxidant, Hyaluronidase, and Collagenase Inhibitory Activities of Glutinous Rice Husk Extract by Aqueous Enzymatic Extraction

Abstract

In this research, we aimed to compare the biological activities related to cosmeceutical applications of glutinous rice husk extracted by aqueous enzymatic extraction (AEE) and conventional solvent extraction. Cellulase enzymes were used to assist the extraction process. The vanillic and ferulic acid contents of each extract were investigated by high-performance liquid chromatography, and their antioxidant and anti-aging activities were investigated by spectrophotometric methods. The irritation effects of each extract were investigated by the hen’s egg test on chorioallantoic membrane. The rice husk extract from AEE using 0.5% w/w of cellulase (CE0.5) contained the significantly highest content of vanillic and ferulic acid (p < 0.05), which were responsible for its biological activities. CE0.5 was the most potent antioxidant via radical scavenging activities, and possessed the most potent anti-skin wrinkle effect via collagenase inhibition. Aside from the superior biological activities, the rice husk extracts from AEE were safer than those from solvent extraction, even when 95% v/v ethanol was used. Therefore, AEE is suggested as a green extraction method that can be used instead of the traditional solvent extraction technique given its higher yield and high quality of bioactive compounds. Additionally, CE0.5 is proposed as a potential source of natural antioxidants and anti-aging properties for further development of anti-wrinkle products.

Naturally Occurring Functional Ingredient from Filamentous Thermophilic Cyanobacterium Leptolyngbya sp. KC45: Phytochemical Characterizations and Their Multiple Bioactivities

“…KC45 on collagenase enzyme activity were investigated, and are shown in Figure 3 . The ethanolic extract can inhibit the collagenase enzyme at IC 50 rates of 3.36 mg/mL (49.12 mg-EGCGE/g-extract), which are in line with the extracts (IC 50 = 0.01–6 mg/mL) from white tea [ 28 ], glutinous rice husk [ 111 ], Turbinaria decurrens Bory [ 114 ], and Citrus unshiu orange [ 115 ]. The phytochemical extract’s pigments [ 114 ] and phenolic components [ 115 ] have collagenase inhibitory action.…”

“…Since collagenase is the enzyme that is capable of degrading collagen, which is a major component of the extracellular matrix that plays key functions in skin tightening and skin resilience, inhibiting this enzyme would lead to a delay in the aging process associated with the skin [ 111 , 112 ]. Collagen fibers have usually been thought of as the main fibrillar component of the skin’s dermis layer, a layer of connective tissue between the outermost skin layer (the epidermis) and the deepest skin layer (the subcutaneous fat layer).…”

Rice Byproduct Compounds: From Green Extraction to Antioxidant Properties

“…The difference between these two techniques consists only in the presence or absence of water during the extraction process. In AEE, water is used to solubilize the enzyme, and then the enzyme aqueous solution is added to the rice-husk extract [54]. In contrast, in EAE, water is used as an extraction solvent to solubilize the rice husk, and the enzyme is added afterwards [73].…”

“…In rice husk, phenolic acids are mainly present in the bound form, and p-coumaric acid, ferulic acid, and vanillic acid (in descending order of abundance), are the main bound phenolic compounds identified in it, as well as in glutinous and roasted rice husk [53][54][55]. Other compounds, such as gallic acid, p-hydroxybenzaldehyde, p-hydroxybenzoic acid, syringic acid, and cinnamic acid, have been detected in rice husk from several rice varieties [56].…”

“…Nonetheless, in the last ten years, some green applications using husk have been reported in the literature. For example, Jiamphun et al exploited the EAE advantage of reduced time and cost to increase the extraction yield of antioxidant compounds from glutinous rice husk [54]. It is known that glutinous rice husk contains a higher content of antioxidants than does non-glutinous rice husk [88].…”