Xylanase enzyme is a thermostable enzyme produced by thermophilic bacteria which in this study used Aneurinibacillus thermoaerophilus SSA2 isolates. Xylanase enzyme is able to hydrolyze xylan into xylose and xylooligosaccharides. The use of xylan in large quantities was very ineffective because of the high price and low production at this time, therefore it was necessary to find a cheaper substrate, derived from agricultural waste and potentially as an alternative to replace xylan. The purpose of this research was to find a replacable substrate of xylan from agricultural waste containing hemicellulose. Xylan of extraction results from some agricultural waste are mixed into the fermentation medium. Extraction results that produce the most optimum enzyme activity will be treated to find the optimum concentration of the substrate. This research is an experimental study using RAL, where each treatment has 5 replications. Data on the results of enzyme activity were further analyzed by ANOVA test and and continued with DMRT test at a significant level of 0,05. The results showed that the the results showed that the administration of agricultural waste substrate as a substitute for xylan affected the xylanase enzyme activity, were straw substrate had the highest average of enzyme activity at 6,033 Unit/mL and the husk substrate had the lowest average of enzyme activity at 5,667 Unit/mL. Substrate concentration had no significant effect on xylanase enzyme activity.

Microalgae Chlorella vulgaris contains micronutrients such as mineral zinc and selenium having role to produce antibody and improve body immunity. However, the impact of Chlorella vulgaris supplementation to goat milks’s chemical compositions has not being well documented. This research’s objective is to identify Chlorella vulgaris suppmentation as zinc and selenium source to improve goat milk’s quality as health drink in COVID-19 pandemy. Fifteen Etawah cross breed or Peranakan Etawa (PE) goats groupped into 5 treatments dan 3 repetitions. The goats were fed with grass, tofu waste and tempe waste. Chlorella supplement is fed to treated goat feed every day with level 0g (P0 = control), 2, 5g (P1), 5g (P2), 7, 5g (P3), and 10g (P4). The research’s result shows that zinc content in goat milk increase 2, 12 ppm or 24, 67%, while selenium increase 0, 08 mcg or 5, 5% after getting supplementation of Chlorella 10g/goat/day (P4). The provision of Chlorella also increase as solids total, protein and milk fat. Milk production increased by 28, 36% with Chlorella vulgaris supplements (P4). Based on the results of this study it can be stated that Chlorella vulgaris supplementation in goat PE feed can be used as a source of natural zinc and selenium minerals to improve the quality of goat milk as a health drink to increase body immunity, especially during the Covid-19 pandemic.

The variety of contents of the growing medium has become a factor to determine the quality of microalgae. Medium derived from the extract of bean sprouts waste, wastewater of tofu industry, wastewater of tempe industry, and wastewater of poultry feces have been tested to observe the growth of local microalgae. The culture placed in 250 ml Erlenmeyer flask aerated and lighted with a 40 watt TL lamp. Every type of waste with 6 concentrations was tested to see its growth. The observation has been conducted to observe population density within 20 days. The observed parameters are dry weight, protein, fat, Vitamin A, C, and E. All of them were tested at the end of the experiment. The result shows that the wastewater of tempe industry with a 4% concentration is the optimum medium for growing local microalgae. The population density was 1.02 x 104 cell/ml and attained on the 10th day of the experiment. The highest dry weight is bean sprouts extract, which is 13.03 mg/l. The content of crude protein ranging from 58.23 %-63.07%, crude fat ranging from 20.88%-21.56%, Beta carotene ranging from 6.3 mg/gram-8.0 mg/gram, Vitamin C ranging from 2.24 mg/gram-2.62 mg/gram, and the content of Vitamin E is 0.8 mg/gram-1.14 mg/gram. It can be declared that the wastewater of tempe industry can be used as a medium for growing local microalgae. Local microalgae biomass can be the candidate of feed supplement for broiler since it contains nutritions.

Microalgae have been studied for long as a functional foods and as food supplements for health. Microalgae contain nutrients and act as antimicrobials, natural antioxidants, anti-cholesterol and contain growth hormones. The research objective was to determine the application of fresh liquid chlorella (FLC) as a natural supplement on performance and broiler blood cholesterol for food safety. One hundred broilers were grouped into 5 treatments and 4 replications, each group consisting of 5 heads. FLC was given in drinking water with a concentration of K0 = 0 FLC cells FLC ml -1 , K1 = 10 4 FLC cells ml -1 , K2 = 10 5 FLC cells ml -1 , K 3 = 10 6 FLC cells ml -1 , K4 = 10 7 FLC cells ml -1 . The parameters measured; 1) broiler performance: feed consumption (g), body weight (g), feed conversion, carcass percentage (%); 2) broiler blood cholesterol (mg dl -1 ). The results showed that supplementation with a concentration of 10 7 cells FLC ml -1 (K4) gave the best performance, body weight gain increased by 8.5% compared to control (K0). The ration conversion ranged from 1.23 to 1.25 and the percentage of carcass was 4.0% higher than the control. Blood cholesterol decreased in line with the increase in the provision of FLC in drinking water, which was between 135 dl -1 (K0) down to 125 mg dl -1 (K4). Application of FLC in drinking water with a concentration of 10 7 cells FLC/ml, can improve performance and reduce broiler blood cholesterol for food safety.